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Markets & Economics of Mixed Waste Paper as a Boiler Fuel January-1990
In Proceedings of Energy from Biomass and Wastes XIV Conference January 1990, Lake Buena Vista, Florida (In Press) MARKETS AND ECONOMICS OF MIXED WASTE PAPER AS A BOILER FUEL By John Kim Lyons and James D. Kerstetter Washington State Energy Office Olympia, Washington 98504 ABSTRACT Mixed waste paper (MWP) is the second largest component of the municipal solid waste steam disposed of in Washington State. Recent state legislation has mandated source separation of recycled material including MWP. The quantity collected will soon saturate both domestic and foreign markets. An alternative market could be as a fuel in existing combustors. The use of MWP as a fuel requires environmental and economic acceptance by potential users. MWP was analyzed for heavy metal concentrations and elemental composition and found to be similar to existing solid and fossil fuels bummed in existing boilers. Existing regulations, however, may classify MWP as a municipal solid waste, thus increasing the capital and administrative costs of using this fuel. The cost of processing MWP into a fluff and a pellet was determined. Three existing facilities were studied to determine the capital and operating costs for them to use MWP fuel. In all cases, the cost of processing and transporting the fuel was greater than the break-even price that could be paid by the potential users. ~ « JK/geb N-R1-27 MARKETS AND ECONOMICS OF MIXED PAPER AS A BOILER FUEL Introduction The state of Washington is currently undergoing major changes to the way it ad- dresses solid waste management issues. One of the most significant elements of these activities has been the passage of Engrossed Substitute House Bill 1671 (ESHB 1671), the Waste Not Washington Act. Passed into law in the spring of 1989, ESHB 1671 mandates source separated recy- cling as the state’s fundamental waste management strategy, and provides technical as- sistance and funding mechanisms to accomplish this goal. As a result, local govern- ment recycling efforts are expected to increase dramatically, thereby reducing the volume of materials to be landfilled in the state as well as increasing the supply of recyclable materials to the marketplace. As the major component of solid waste, the recovery of waste paper products is an essential part of ESHB 1671, and efforts towards the identification and enhancement of traditional waste paper markets were directed by the bill. The bill also addressed the need for identifying new markets for waste paper and placed a particular emphasis on identifying market opportunities for mixed waste paper (MWP) due to the large volume of MWP generated in the state. To this end, ESHB 1671 instructed the State Energy Office, in co-operation with the Department of Trade and Economic Development, to evaluate the potential use of MWP as a fuel for existing boilers. Technical, economic, and environmental issues re- lated to the use of MWP as a fuel were called for and examined within this study. In addition, a feasibility analysis evaluating retrofit requirements and costs for specific users of MWP was completed and an assessment of the market value of MWP to these users was made. Resource Availability & Characteristics Type The American Paper Stock Institute (APSI) classifies MWP as low grade paper such as magazines, books, scrap paper, non-corrugated cardboard (boxboard/chip- board), and construction paper. Occasionally, shipments of higher grade papers, such as old newspaper and office paper, may be classified as MWP if significant amounts of lower grade paper are incorporated. APSI also includes special subcategories of waste paper, such as used telephone books or blueprints, in its MWP designation. Papers, such as carbon paper, tissue, contaminated food cartons, wax paper, and waxed cardboard, are considered contaminants by the APSI. Given the wide range of materials which fall under the MWP designation, sig- nificant variations are likely between loads and even within a given load. The source of the material and the technique for recovery largely influences the character and com- position of MWP. For example, MWP collected from a residential curb-side recovery program will differ considerably from MWP recovered from a commercial recycling program. In the former case, the type of materials recovered will include consumer packaging materials, such as cereal boxes, as well as “junk” mail and magazines. In contrast, commercial MWP will contain a high degree of mailers, various grades of ledger, magazines, and even some computer paper. In both cases, a certain amount of contaminants, including plastic, should be expected. The majority of MWP collected by local governments will be from individual residences, and the composition of MWP should be predominantly of this type. The City of Seattle’s curbside program provides an example of the types of materials recovered which include magazines, catalogs, binder paper, stationary, “junk” mail (in- cluding small amounts of plastics, such as found in “window” envelopes), brochures, and cereal boxes (without the inside liner). The program does not accept waxed materials (milk cartons or frozen food containers), tissues, used paper plates, or carbon- less (NCR) paper. MWP from the Seattle program also does not include newspapers or corrugated containers, which are collected but marketed separately. Generated In 1987-88, the Department of Ecology (Ecology) conducted a comprehensive analysis of the solid waste stream in Washington State.(7) According to the Ecology survey, Washington State citizens generated approximately 1.7 million tons of waste paper during 1987. This amount is equivalent to 32 percent of the total solid waste generated in the state, and establishes waste paper as the largest single component of the state’s solid waste stream, as shown in Figure 1. Washington State Waste Stream - 1987 35% Nonrecycladle 12% 2% Nowe Total Waste Paper: 1,692,000 tons Total Waste: 5,260,000 tons - Source: Ecology-1987 Recycling Burvey Figure 1 Of the various sub-categories of waste paper, MWP is the second largest com- ponent found in the waste stream comprising 27 percent of the total, or 459,294 tons. As expected, the majority of the MWP generated in the state occurs in the Puget - Sound basin which accounts for more than 60 percent of the state’s total. When com- bined with the other west-side generation areas, western Washington is responsible for approximately 80 percent of the total MWP generated in the state, while eastern Washington is responsible for the remaining 20 percent: A breakdown of waste paper generation areas is presented in Figure 2. Generation of Mixed Waste Paper In Washington State West N.W. Puget SW. N.C. SC. NE SE. Waste Generation Areas Source: Denartment of Ecology Figure 2 Nationally, trends in municipal solid waste (MSW) generation show that paper is increasing as a percentage of MSW.(3) In part, this is due to a shift towards a service and information based economy. It is also well established that paper consumption (and discards) closely “track” real GNP, and thus economic activity. For Washington, or more particularly the Puget Sound area, economic forecasts indicate a fairly robust economy through at least the year 2000 coupled with a significant increase in popula- tion growth. The Ecology Advisory Committee, reviewing secondary fiber uses, indi- cates MWP will represent 34.7 percent of the total waste paper stream by the year 2010, and will account for 961,291 tons of generated waste.(10) Recovered Whereas MWP represents 27 percent of the total waste paper generated in the state, very little of it is currently recycled as shown in Figure 3. The Ecology survey in- dicated that only 7.4 percent of the MWP stream, or 34,000 tons, was collected for recycle markets in 1987. In comparison, newsprint, corrugated, and high grade papers were recovered at a rate close to 50 percent.(7) Although currently low, recovery rates for MWP are expected to increase dramati- cally as municipalities across the state establish local recycling programs. This an- ticipated increase was already in evidence in a follow-up survey conducted in 1988 which identified a 95 percent increase in the recovery of MWP.(10) Although small in comparison to the total MWP generated in the state, this increase foretells future trends as local governments respond to ESHB 1671. While ESHB 1671 ensures an increased recovery of MWP, the degree of recovery will be responsive to price signals, with the recycle marketplace setting prices on one side and the cost of landfilling setting the other. In communities where a strong market Washington State Waste Paper Stream Coneater Nonrecyclable Newsorint cress gm Disposed e3% 355 — Total Mixed Waste Paper: 459,000 tons Recycled 7 Total Waste Paper: 1,692,000 tons Source: Ecology-1987 Recycling Survey Figure 3 for MWP exists and tipping fees are high, the recovery of MWP should also be high. In contrast, for those communities which are isolated from markets or have low tip- ping fees, the recovery of MWP-will probably be low. Because of the uncertainty of market conditions, the rate at which MWP will be recovered is difficult to forecast. However, an estimate of MWP recovery rates for the year 2010 was projected by the Ecology Advisory Committee which indicated a rate of 22.4 percent or 215,600 tons per year.(10) Markets Traditionally, the demand for MWP both in Washington and throughout the U.S., has been low, with the primary markets being the paperboard and construction paper industries and overseas export, as indicated in Figure 4. On a national level, ap- proximately 2,165,000 tons of MWP were consumed in the production of paperboard and construction paper in 1980. By 1988, only 2,085,000 tons of MWP were con- sumed by these two industries.(2) - While the domestic use of MWP has remained flat over the last decade, the markets for construction paper and paperboard have grown.(2) The increased demand for raw materials by these two industries has been met by an increased availability of recycled corrugate and other pulp substitutes. Industry analysts expect this trend to continue as more and more cormugate and higher grade pulp substitutes are recovered.(4) In contrast to the domestic demand for MWP, overseas sales of MWP has been steadily increasing. In 1980, approximately 649, 000 tons of mixed paper were ex- ported from the U.S., with South Korea, Taiwan, Mexico, Italy, and Canada being the primary importers. By 1988, U.S. MWP exports increased to 884,000 tons and now ac- count for nearly 30 percent of the total MWP market.(2) National Use of Mixed Waste Paper By End-Use Categories paperboard construction pape paperdoard 352 1732 exports construction paper 649 772 export 884 MWP Use - 1980 MWP Use - 1988 (1000 tons/yr) (1000 tons/yr) Source: American Paper Institute - 1989 Figure 4 In Washington State, markets for MWP are even more dependent on overseas sales than occurs nationally. In 1987, approximately 34,000 tons of MWP were recovered in Washington. By 1988, the recovery of MWP increased to 65,600 tons, of which ap- proximately 55,000 tons were sold to export markets. This amount is equivalent to ap- proximately 7 percent of the total overseas sales of MWP (7,10) in the U.S. during 1988. . As expected, saturation of the export market for MWP is of real concem to waste paper brokers. For example, Washington State’s share of the MWP export market would approach 60 percent of the total national market if all of the MWP generated in Washington during 1987 were recovered and sold overseas. Discussions with various brokers operating in the state revealed that the price paid for MWP by foreign im- porters is steadily decreasing as more and more MWP hits the market. At the same time, escalating shipping rates are cutting into the already marginal retums resulting from the sale of MWP, causing some MWP brokers to remark that they might have to limit the amount of MWP they handle or get out of the market all together. As of the late fall of 1989, the average rate recovered by Washington brokers of MWP was from $10 to $15 per ton discounting shipping costs. Suppliers of MWP, which would in- clude local government recycling programs and private recyclers, received from $0 to $5 per ton for MWP. The remaining 10,600 tons of MWP recovered in 1988 were consumed by in-state manufacturers specializing in paperboard products.(10) Currently, there are only three such MWP consumers in Washington: Container Corporation of America, Sonoco Products Company, and Keyes Fibers. Container Corporation and Sonoco produce chipboard, boxboard, linerboard, and core stock, among other products, while Keyes Fibers specializes in the production of molded fruit packing trays and pads. All three of these companies use varying amounts of MWP in their production line which they blend with other secondary fibers. The combined daily output of these three com- panies is approximately 200 tons per day of which only a small fraction is comprised of MWP fibers. Outside of these three paper producers, preliminary findings from an Ecology Ad- visory Committee investigating recycled paper as a feedstock suggest that there is little interest in MWP by Washington’s pulp and paper industry. Concem over the quality of MWP fiber, coupled with the high cost of retooling, were cited by industry repre- sentatives as being a major roadblock to using MWP anytime in the near future. ~ Given that neither the export market or the existing domestic market can realistical- ly absorb a large increase in the supply of MWP, the need for altemative markets for MWP becomes increasingly important. The following sections examine the technical, environmental, economic, and market issues surrounding the use of MWP as a fuel. Environmental Considerations For MWP to be accepted as a fuel, it must be priced competitively with other fuel types, it must have good fuel value, and it must meet all existing environmental com- pliance standards. While the first condition will be determined by the marketplace, the latter two conditions are measurable. The scientific literature contains little informa- tion on the chemical composition of source separated MWP. A recent study by the California Solid Waste Management Board did report data on MWP that was separated from municipal solid waste.(5) They collected ten loads of solid waste from the receiving pit at the Commerce waste-to-energy plant. Each load was separated into 13 components and analyzed for heavy metals and elemental composition. One of the components was classified as MWP. Table 1 shows the results of those tests. No data was found on the analysis of source separated MWP. A sampling and analysis pro- gram was developed to characterize this material. Table 1 Analysis of Mixed Paper from Commerce Waste-to-Energy Plant Component Average © Minimum Maximum as received basis. Arsenic, ppm 20.7 9.6 33.9 Barium, ppm 4.7 2.1 18.7 Cadmium, ppm 0.75 0.25 2.1 Chromium, ppm 63.4 11.0 414 Lead, ppm 44.4 6.6 131 Mercury, ppm 0.012 0.004 0.034 Zinc, ppm 249 52 805 Chlorine, % 0.235 _ 0.05 0.52 Moisture, % 12.6 5.4 30.0 . Ash, % 9.3 4.7 11.9 Sampling Techni To date, there is no established protocol for sampling of MWP. While an extensive sampling program could be developed and ultimately might be required, the time and resources needed are beyond the scope of this evaluation. We confined our sampling to recycling brokers. In Washington, a small group of brokers handle the majority of the MWP recovered in the state. These brokers either purchase, or in some cases, collect MWP directly, which they then grade and process into bales for handling and shipment to both local and overseas markets. As each bale contains approximately 1,440 pounds of compressed MWP, it was felt that samples extracted from a number of bales should contain a fairly good cross- section of MWP products. Given this assumption, sampling at three of the main brokerage facilities was secured and a survey of sampling protocol was conducted. A review of the literature indicated that a coring technique had been experimented with for sampling of RDF products. This technique, while generally dismissed for RDF sampling due to excessive wear and tear to the corer, appeared to represent a method wherein wastepaper bales could be readily sampled. Following further discussions with representatives of the pulp and paper industry, a modified coring technique was selected for sampling. Bales containing MWP were randomly selected at each of the three collection facilities and set aside for sampling. Each bale was then drilled perpendicular to the baling layers to approximately the cen- ter of the bale. This was done three times per bale using a 3/4 inch auger bit in place of a corer. The materials from the drilling were collected and sealed in a plastic bag and sent to an analytical lab for analysis. Each sample collected weighed approximately one and one-half ounce. A total of 12 separate bales were sampled using this method and are broken out in the following categories: five bales post-consumer mixed commercial, four bales source separated mixed residential, and three bales non-source separated mixed residential. Two additional samples, one grab and one drill, were taken of pre-con- sumer, unprinted, hard white paper to test for contamination by the auger. Analysis The sealed samples of MWP were mailed to a local laboratory for analysis. Prior to analysis, each sample was reduced to a particle size of 0.5 mm using a Wiley Mill and then riffled to ensure that the analysis sample was representative of the field col- lected sample. Sample analysis included proximate analysis, wtimate analysis with chlorine, and elemental analysis for the following trace metals: Antimony (Sb), Arsenic (As), Barium (Ba), Beryllium (Be), Cadmium (Cd), Cobalt (Co), Chromium (Cr), Copper (Cu), Manganese (Mn), Molybdenum (Mo), Nickel (Ni), Lead (Pb), Selenium (Se), Tin (Sn), Zinc (Zn), and Mercury (Hg). Metals analysis was conducted using standard (EPA, ASTM) acid extraction tech- niques followed by graphite furnace atomic absorption (GFAAS) or plasma spectrophotography (ICP). The procedure for mercury includes pre-digestion via hydrolysis using 72 percent sulfuric acid followed by atomic absorption. Concentra- tions were reported in mg/kg on an as received basis. Ultimate analysis was conducted using the methods detailed in ASTM D3176-84. Sulfur and chlorine analysis followed ASTM D4239-85 and ASTM D2361-85 protocol, respectively. Similar ASTM analytical protocol was followed for proximate and heating value analysis. Results igher Heating Value an. timate and Proximate Anal Higher heating value (HHV) determinations and ultimate and proximate analysis are presented in Table 2. Measured concentrations are given in percent of total on an oven dry (OD) basis, and include average as well as maximum and minimum values. Table 2 Elemental Analysis Avg Min Max #1 #2 #3 #4 #5 #6 #7 #8 #9 «#10 #11 #12 weight percent, dry basi Moisture 733° 52 109 $2 SS $3 68 62 7.7 109 86 86 82 67 83 Ash 984 67 148 79 110 101 92 90 79 94 10.3 127 67 148 91 Volatile 8281 763 926 NA NA NA NA NA 85.0 825 80.7 763 92.6 77.9 84.7 FxdCbon 7.09 0.7 111 NA NA NA NA NA 7.1 82 9 bt 07 73 62 Carbon 41.16 38.7 44.6 40.1 40.0 39.7 40.7 41.9 421 43.0 40.7 41.3 44.6 38.7 41.1 Hydrogen 621 S58 67 59 S8 62 60 61 62 65 62 65 67 61 6.30 Nitrogen O11 Of O02 OF OF Of OL OF Of OF Of OF Of OF 02 Sulfur 0.07 0.02 0.09 0.02 0.06 0.05 0.08 0.09 0.09 0.09 0.06 0.07 0.09 0.07 0.09 Chloride 0.14 0.02 0.64 0.09 0.08 0.06 004 002 0.1 0.64 0.06 0.42 0.05 0.04 0.08 HHV/ 7,187 6,680 7,880 6,680 6,890 6,850 7,260 7,330 7,450 7,590 7,130 7,300 7,880 6,700 7,180 Bub Metals Analysis The results of the metals analysis are presented in Table 3. Concentrations are presented in mg/kg on a dry basis and represent the total metals content contained in the sample. Average concentrations and maximum/minimum values are also given. Table 3 Heavy Metal Concentrations Avg Min Max #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 —_ — megkeg, dry basi. Arsenic 048 0.0 0.93 0.29 <06 <06 0.07 <06 0.93 084 09 057 082 075 0.6 Barium 46.21 25 92.7 25 220 249 24.1 27.2 48.7 57.2 708 574 61.8 65.2 927 Beryllium 07 <3) 19 03 03 03 03 03 10 Lt 19 #10 Ld 1.2 1.10 Cadmium 055 <3 19 03 03 03 03 03 09 LI 19 09 09 <3 09 Cobalt 678 <3 148 03 03 03 06 OS 112 104 121 103 100 148 111 Chromium 648 0.7 114 0.7 41 42 39 114 50 68 96 69 81 84 86 Copper 18.12 18 383 18 83 76 216 188 60 15.2 206 19.7 383 35.2 243 Manganese 27.34 79 869 79 9.6 124 20.1 186 11.6 246 30.7 23.6 869 528 29.3 Molybden 742 10 139 29 13 17 15 10 ILS 114 123 10.7 106 139 10.2 Nickel 692 <1 140 <1 10 <I <l <1) 110 11.0 130 11.0 11.0 140 11.0 Lead 751 07 495 O07 114 121 182 495 24 80 79 62 15 21 76 Antimony 388 <3 100 <3 <3 <3 <3 <3 75 70 80 60 40 100 4.0 Selenium 0.06 <06 0.13 <06 <06 <06 <06 <06 0.09 0.13 0.09 0.08 0.12 0.08 0.07 Tin 792 30 140 30 40 50 50 40 130 10.0 100 9.0 100 140 80 Zinc 149.21 85 837.0 85 8370 383 36.9 47.4 9.7 175.0 116.0 34.7 298.0 81.0 108.0 Mercury 0.05 <05 0.33 <05 <05 <05 <05 <05 0.07 0.33 0.09 <05 007 <05 <.05 Discussion: Based on ultimate and proximate analysis, it appears that MWP would make a suitable fuel. Figure 5 illustrates the relative fuel value of MWP as compared against other solid fuels. As shown, MWP compares favorably to both hog fuel (wood) and Black Diamond coal with respect to moisture, ash, and higher heating value, and is su- perior to mass-burn municipal solid waste and refuse-derived fuels. While MWP appears to have acceptable fuel characteristics, users and regulators alike need to be certain that MWP would not create any significant environmental com- pliance problems when bumed. Ideally, these concems would be addressed through a Series of test bums coupled with continuous emissions monitoring and ash toxicity analysis. The high cost of conducting test bums at this stage of investigation, however, precluded direct field measurements. Instead, the results of ultimate and elemental analysis were used to calculate potential air emission and ash toxicity levels which could result from the buming of MWP. Furthermore, when hammennills are used for size reduction, they can drive small pieces of metal into the combustible material that are difficult to remove. Comparison of Solid Fuel Types Fuel Characteristics Moisture (%) HHV, MBtu/Ib El MP EE Wood BR Coal (7 MSW E&] ROF Figure 5 Ash The presence of heavy metals in the ash from both mass-bumn MSW and refuse- derived fuel is well documented.(6) Similar concems over the potential for contamina- tion of MWP ash have been raised. Table 4 presents trace metal results in parts per mil- lion (ppm) on a dry basis for averaged concentrations. Included in the table are the results from two other studies examining the heavy metal composition of various waste streams. The Bureau of Mines (BOM) and Ames studies investigated metal con- centrations in the combustible fraction of MSW for various locations.(6,8) 10 Table 4 Heavy Metal Content in MSW (ppm on a dry basis) BOM Ames This study (average) (average) (average) Lead, ppm 330 610 7.5 Zinc, ppm 780 760 149 Cadmium, ppm 9 NA 0.55 Mercury, ppm 1.2 - 0.05 Tin, ppm 20 - 719 Barium, ppm 170. - 46.2 Copper, ppm 350 570 18.1 Chlorine (%) 0.45 0.22 0.14 While differences in methodology limit detailed comparison between the studies, it appears that the average concentrations of heavy metals found in the MWP samples are significantly lower than those found in the BOM and Ames investigations. This is to be expected as both the Ames and BOM studies examined refuse derived fuel (RDF). RDF processing usually involves only minimal screening and separation of the waste stream which often results in the mixing of combustible and non-combustible materials. MWP sample results were also compared to the Environmental Protection Agency’s Extraction Procedure (EP) Toxicity test for ash. The EP Toxicity test is one of the primary tests used by environmental regulators to determine whether a material should be designated as a hazardous waste. Calculated values for the metal concentra- tion were determined and not actual extraction tests. Ash Toxicity Mixed Paper Samples le) Calculated leachate, mg/liter (! Figure 6 11 To allow for comparison with the EP Toxicity limits, the following conservative assumptions were applied. First, it was assumed that the paper sample undergoes com- plete combustion and that all the metals are contained in the ash. Second, it was as- sumed that for each element, all of the metal, not just the soluble portion, would be ex- tracted from the ash during the extraction process. Table 5 shows the theoretical maximum concentration of metals which would be found in the extract. Measured concentrations using the EP test methodology would be substantially less than shown as only the soluble portion of the metals would leach out and be present in the extract. Even so, the average, or sample mean, is less than the EPA standard for the eight metals of concem, and would not be classified as a hazard- ous material using the EPA Toxicity Test definition as indicated in Figure 6. It should be noted, however, that these results represent the average of the sample set, while in- dividual samples might exceed threshold limits. Table 5 Calculated EP Toxicity Values Avg Min Max #1 #2 #3 #4 #5 #6 #7 48 #9 #10 #11 #12 TT phliter, dry basis Arsenic ND ND ND 0.18 ND ND 0.04 ND 059 045 0.44 0.22 0.61 0.25 0.33 Barium 24.12 1.58 50.93 1.58 10.0 12.33 13.1 15.11 30.82 30.43 34.37 22.6 46.12 22.03 50.93 Beryllium = ND Cadmium ND Cobalt ND ND ND ND ND ND ND 0.63 059 0.92 039 0.82 O41 0.6 ND ND ND ND ND ND 057 059 092 035 0.67 ND 049 ND ND ND 0.15 0.33 0.28 7.09 5.53 587 4.06 7.46 50) 6.1 Chromivm 3.38 O44 633 O44 186 2.08 2.12 633 3.16 3.62 4.66 2.72 6.04 2.84 4.73 Copper 953 1.14 2858 1.14 3.77 3.76 11.74 10.44 38 8.09 10.0 7.76 28.58 11.89 13.35 Manganese 15.01 4.36 64.85 5.0 436 6.14 10.92 10.33 7.34 13.09 14.9 9.29 64.85 17.84 16.1 Molybdenu 3.86 056 7.91 184 059 0.84 082 056 7.28 6.06 5.97 421 7.91 47 56 Nickel ND.ND ND ND 045 ND ND ND 696 5.85 6.31 433 821 4.73 6.04 Lead 4.01 0.44 275 044 052 06 0.99 27.0 152 426 383 2.44 1.12 0.71 4.18 Antimony ND ND ND ND ND ND ND ND 475 3.72 3.88 2.36 2.99 338 622 Selenium ND ND ND ND ND ND ND ND 0006 007 0.04 0.03 0.09 0.03 0.04 Tin 4.14 182 823 1.90 182 248 272 222 823 532 485 354 746 4.73 440 Zine TI46 5.38 3804S 5.38 38045 18.96 20.05 26.33 6.14 93.09 56.31 13.66 222.39 27.36 59.34 Mercury ND ND ND ND ND ND ND ND 0.04 0.18 0.04 ND 005 ND ND 88 Note: Sample Calculation: Sample #1 contained 2.5 ppm Ba (2.5 mg Ba/kg paper) and 7.0% ash (7.9 g ash/kg paper). The EP Toxicity Test extracts 100g of ash into 2 liters of sol- vent. Assuming all the Ba is in the ash and it is all extracted into 2 liters of solution, then the maximum Ba concentration is calculated as follows: 25mgBa x lJkgpaper x 100gash = 1.5 mg Ba kg paper 7.9 g ash 2 liters liter While elemental analysis shows that MWP can be a potential source for some heavy metals, the ash resulting from the combustion of MWP should not be expected to be classified as a hazardous waste under the EP Toxicity test. For added perspec- tive, Figure 7 presents calculated heavy metal concentrations in MWP ash as com- pared to measured concentrations in wood and coal ash, the latter two being regulated as a solid fuel ash. The wood ash data was taken from an analysis of a cogeneration plant which fires wood waste, while the coal ash data was extracted from a report which summarized the results of 27 coal buming plants across the nation.(1) 12 Heavy Metal Concentration in Wood, MWP and Coal = Metals in Total Ash, ppm - im Heavy Metals Wood [=] MWP BBB} Coal As shown, for the six heavy metals examined, the concentrations found in coal ash exceed those calculated for the MWP ash for all but zinc. Similarly, concentrations of lead, arsenic, barium, and chromium are reported to be higher in the wood ash than would be found in the MWP ash. While these results are by no means definitive, they do suggest that MWP ash is probably not anymore harmful than certain coal and wood ash. : Complete combustion of fuels converts carbon to carbon dioxide, hydrogen to water, sulfur to sulfur dioxide, chlorine to hydrochloric acid, and nitrogen to nitrogen gas. Knowledge of the fuel’s elemental composition and combustion conditions per- mits calculation of the volume of each gas emitted. The concentration of the acid gases, HCI and SO2, can be calculated for the standard conditions used to set regulatory limits (68°F, 760 mm Hg, 7% O2). Figure 8 presents both SO2 and HCI cal- culated emissions for MWP, coal, wood, MSW, and RDF in an uncontrolled state. As shown, SO2 emissions for MWP should be lower than expected for either wood, coal, RDF, or MSW emissions, while a slight increase in HCI should be anticipated when burning MWP over either wood or coal. Figure 7 Emissions of products of incomplete combustion (PICs) can not be calculated. These products result from the partial combustion of fuels and the major constituent is carbon monoxide. Toxic substances may also be found in trace quantities and those of most concem are dioxins, furans, and polychlorinated biphenyls. Toxic metals can also be emitted. Emission results from a test bum conducted in the state of Wisconsin provide addi- tional insight into possible emissions resulting from the firing of MWP. In this case, pre-consumer MWP was co-fired with a 50 percent mixture of coal. The results of con- tinuous emissions monitoring are presented in Table 6 and indicate that in this instance 13 a reduction in SOz, NOx and criteria metals emissions occurred. The test burn also showed an increase in particulate loading as well as an increase in HCI emissions.(13) Air Emissions Acid Gases E & 2 Ss 3 £ ui 3 & Da 2 & 5 Figure 8 Table 6 Emissions Test Results University of Wisconsin Increases 100% Coal Coal/Pellets w/Pellets Average Particulates Concentration grains/dscf 0.1276 0.1564 24.68 HCl (ppm) 64.61 115.4 78.61 Total Gaseous Non-Methane Organics (ppm) 224 139 -37.95 Average CO (ppm) 52 55 5.74 Average SO2 (ppm) 647 514 -20.53 Average NOx (ppm) 255 83 -67.7 PCB Emissions (lbs/hr) 7.6E-09 4.3E-09 -43.42 Metals Emissions: Arsenic mg/m3 0.2 0.21 -8.4 Beryllium mg/m3 0.02 nd Cadmium mg/m3 nd nd Chromium mg/m3 0.39 0.29 -33.19 Lead mg/m3 0.63 0.67 -4.55 Mercury mg/m3 0.022 1.1 -23.08 Nickel mg/m3 0.77 2.6 -48.36 Zinc mg/m3 14 1.9 25.15 14 Regulatory Considerations Air Regulati The Federal Clean Air Act (CAA) identified certain criteria pollutants for regula- tion and authorized the identification of non-criteria pollutants to be regulated for specific sources. Table 7 lists these pollutants. The CAA also adopted National Am- bient Air Quality Standards for criteria pollutants. These standards are used as a basis for setting emissions limitations. Table 7 Regulated Air Pollutants Criteria Pollutant Non-Criteria Poll Carbon Monoxide Asbestos Nitrogen Oxides Beryllium Sulfur Dioxide Mercury Particulate Matter Vinyl Chloride Volatile Organics Fluorides Lead Sulfuric Acid Mist Classification of MWP as a fiber fuel or as a municipal solid waste fuel also affects the regulatory standards. There are several cases in the Washington Administrative Code (WAC) where wood has been exempt from the normal solid waste regulations. Chapter 173-434 exempts wood from the solid waste incinerator facilities regulations. Chapter 173-304-440 exempts wood from the energy recovery and incinerator stand- ards under the minimum functional standards for solid waste handling. ESHB 1671, Section 65 excludes hog fuel buming from the need to have certified operators. Chap- ter 173-306 proposes to exempt ash from facilities buming only woodwaste from the special incinerator ash management standards. * Table 8 shows a comparison of regulatory requirements for fuels classified as municipal solid waste and wood. These regulations, used by the Puget Sound Air Pol- lution Control Agency (PSAPCA), are considered to be the most Stringent in the state. It is readily seen that the regulatory requirements are dramatically different for the two fuels. These regulatory differences translate into added capital, operating, and ad- ministrative costs if MWP were considered as MSW. Table 8 Comparison of Regulations for MSW and Wood Fuels Category MSW = Wood Particulate, gr/dscf 0.01 0.02 Opacity, % 10 20 HCl, ppm 30 100 S$O2, ppm 30 1,000 . EIS required yes no Certified operator yes no Computer-based combustion control yes no Particulate control exit temp. <350° yes no Continuous monitoring CO,02,SO2,0pacity yes no Special ash regulations yes no A facility switching fuels may have to undergo a Best Available Control Technol- ogy (BACT) review. That review may require measures beyond the minimum stand- ards such as continuous emission monitoring. However, even the minimum standards for MSW could effectively preclude the use of MWP in existing combustion systems. S 15 For example, if an existing system did not have computer-based combustion controls, then it is unlikely the facility would add this capability only to allow it to bum 10 to 20 percent of MWP fuel. If the existing facility had a stack gas temperature greater than 350°F, it is unlikely they would install an economizer before the final particulate control device merely to permit use of MWP fuel. Often there is no physical space to accommodate retrofit equipment. Economic costs will usually be the deciding factor on the use of MWP fuel, but additional administrative burdens, such as bookkeeping for fuel received and stored, ash disposal records, reporting of emissions, and the need for certified operators, would often dissuade a company from using MWP fuels. The determination of a major source under PSD depends on the emission levels, the type of facility, and whether or not it is a new facility or changes to an existing facility. The significance of being classified as a major source is that the proposed modifications must undergo a BACT review. BACT cannot be any less stringent than the applicable new source performance standards (NSPS). Under court mandate on November 30, 1989, the EPA Administrator signed a proposal on source performance standards for municipal waste combustors under Section III of the Clean Air Act. These standards would not permit Ecology to classify MWP as a fiber fuel. They would also place more stringent standards on existing and new municipal solid waste incinerators than are currently required by Ecology. If these proposed standards are adopted, the use of MWP as a fuel in existing boilers would be unlikely due to in- creased capital, operating and administrative costs. New facilities are classified as major PSD sources if they are one of 28 PSD named source categories and emit more than 100 tons per year of a regulated pollutant. New sources not specifically named, but which emit more than 250 tons per year of any regulated pollutant, are also classified as a major PSD source. Fossil fuel boilers, totaling more than 250 million Btu per hour heat input and municipal incinerators capable of charging more than 250 tons per day of refuse, are named sources. For ex- isting major PSD sources, the EPA has identified certain emission increases as repre- senting major modifications. These increases are: Sulfur Dioxide 40 tons/year Nitrogen Oxides 40 tons/year Particulates 25 tons/year Carbon Monoxide 100 tons/year Ash Regulations: Due to the higher ash content of MWP as compared to the fuel it will offset, greater quantities of ash will require disposal when MWP fuel is com- busted. How the ash is classified and regulated is of foremost interest in determining the methods and costs of ash disposal. Similar to the case of air emissions regulations, whether MWP is classified a fiber fuel or as a solid waste will have a significant im- pact on the disposal requirements. Federal Regulations The U.S. EPA has not yet promulgated regulations classifying solid waste incinera- tion ash either as a solid waste or as a hazardous waste. However, EPA has issued in- terim guidelines which allow disposal of municipal incinerator ash at lined, municipal solid waste landfills which are regulated under Subtitle D of the Resource Conserva- tion and Recovery Act (RCRA). Revisions to Subtitle D regulations are due soon from the EPA. Federal hazardous waste regulations (RCRA Subtitle C) would apply to ash which tests as hazardous. These regulations identify handling, tracking, and disposal require- ments. However, ultimate analyses conducted by the Energy Office on samples of MWP indicate that ash from the combustion of MWP would not likely be considered hazardous. f Washi Regulati In August 1989, Ecology issued proposed regulations for incinerator ash disposal. These regulations are known as the Special Incinerator Ash Management Standards (WAC 173-306 draft #5) and are scheduled to be promulgated in January 1990. These regulations dictate special ash disposal requirements for ash which would otherwise be classified as hazardous waste under Washington State regulations (RCW 70.105). The Special Incinerator Ash Management Standards do not apply to hazardous wastes if such wastes are classified under RCRA Subtitle C. The proposed regulations contain requirements for ash management and disposal, including generator management plans, landfill siting standards, daily cover require- ments, liners, caps, testing, transport vehicle specifications, and record-keeping. Ecology has exempted ash from wood-fired power plants in its proposed Special Incinerator Ash Management Standards. Ash from combusting wood waste is not listed as a dangerous waste in WAC 173-303, the dangerous waste regulations. Test- ing of ash will determine whether it is subject to the dangerous waste regulations. If testing determines that MWP ash (or ash from the co-firing of MWP and the con- ventional fuel) is not subject to the dangerous waste regulations, the ash can be dis- posed at a standard municipal solid waste in a landfill or potentially in a special pur- pose inert waste landfill, usually at a lower cost. Many wood-buming facilities have a nearby site used for ash disposal. If MWP is classified as a fiber fuel, it is likely that the same site could continue to be used. Design Considerations Processing MWP MWP must be processed to prepare it for use as a fuel. One goal of processing is to provide consistent fuel properties, such as size, shape, heat content, flow charac- teristics, and moisture content. A fuel with consistent properties allows better control over handling and combustion processes. A discussion of processing methods, the ad- vantages of each method as it relates to the combustor types, processing costs, and a comparison of MWP fuel with other fuels is presented below. Processing Methods Four different types of processing methods will be described with discussions of the advantages and disadvantages of each. All methods will benefit from the MWP being an entirely combustible feedstock requiring no separation stage or operation to remove undesirable constituents. Recognizing the importance of fire prevention when handling large quantities of paper, a fire suppression system would be designed into the entire materials processing and handling system, from receipt of the feed material to injection into the boiler, bumers, or existing fuel feed equipment. Covered conveyors would contain fire sup- pression piping as would storage silos, bins, and mechanical equipment. Shredding Shredding is considered an appropriate processing step for all combustor types. Shredding is also appropriate for MWP that will be further processed into pellets. Rep- resentative samples of MWP indicate a wide variation in chemical and physical charac- teristics. This variation has the potential to alter the buming characteristics of the fuel in the boiler. Consequently, it is all the more important to control the variability of fuel characteristics to achieve as much uniformity in firing as possible. For this reason, V7 1? shredding of the MWP is highly desirable. The consistency of MWP will vary from that of single, loose items, such as envelopes and single sheets of paper to dense items, such as magazines, catalogs, and telephone books. Shredding of the raw MWP will provide a more uniform sized fuel resulting in improved control of firing rate/heat release and combustion efficiency. Similar benefits will be realized with a gasifier coupled to an oil/gas boiler where a more uniform size of feedstock will result in a more consistent flame. Because the product of the cement kiln is not steam, as with the other combustor types, but the ash clinker itself, the finely shredded fuel obtained from two stages of shredding will provide better combustion and a more consistent ash than that of unshredded MWP fuel. Significant advantages to fuel feed systems result from shredding the MWP. Whether the MWP fuel is injected into the combustor separately from the existing fuel feed system or mixed with the primary fuel ahead of the combustor, the process- ing/preparation obtained from shredding will be advantageous to the operation of the fuel feed system itself. When injected separately, the more uniform fuel particle size obtained from shredding will result in a smoother operating fuel feed system. Not only will this yield a higher degree of control over fuel feed rate, and hence a more consis- tent heat release, it will also result in fewer operational difficulties caused by jamming that could occur when large, bulky items are mixed with smaller items. Similarly, a uniform size MWP fuel feed mixed with the conventional solid fuel feed prior to injec- tion into the burn chamber will give a more uniform bum rate and minimize operation- al difficulties resulting from a widely varying fuel size. The disadvantages of shredding stem from equipment space requirements, opera- tional, and cost considerations. There may not be adequate space in the existing plant to accommodate a shredder installation. Operationally, maintenance of a shredder en- tails frequent inspection/replacement of the impact surfaces and component parts. The capital and installation costs of a shredder are a major consideration as are its power costs. Pelletizing operations will benefit from having a consistently-sized feed stock. Pel- letizer design typically requires the feed stock to be shredded to a size at least as small as the pellet diameter. Pelletizing The objective of pelletizing is to produce a designated MWP having physical and combustion characteristics more comparable to conventional fuels than shredded MWP. Pelletizing allows for more uniform fuel feed into the combustor and easier han- dling and shipping. Experience indicates that successful pelletizer operation typically requires a feedstock moisture content of approximately 20 percent in order to provide sufficient structural integrity to the pellets. Moisture content of MWP is on the order of 5 percent and, consequently, water would be applied to the shredded MWP immediately ahead of the densification process to increase the MWP moisture content. The availability and cost of steam should be evaluated if steam conditioning is considered. The disadvantages of utilizing a pelletizer are its capital cost and its operating and maintenance requirements. Using MWP “As Collected” . Utilization of the MWP in its “as collected” condition is a very attractive option from a cost standpoint. However, it may have serious drawbacks from an operational viewpoint, particularly with regards to combustion control. 18 The appropriateness of this processing method, perhaps more so than any other, is highly site-specific, both with regards to existing plant layout as well as plant operat- ing characteristics. One option would be for the “as collected” MWP to be unloaded into the existing fuel receiving system at the front end. The MWP would then be processed with the current fuel through the same system as is presently being used. This may be appropriate for wood-fired combustors, but it is not feasible for other combustor types. Baling, Then P ingl MWP is commonly marketed in bales to improve its handling characteristics and to increase its density for more economical shipping. Receiving MWP in bales offers the advantage of reduced storage space requirements prior to processing. Bales could be stacked on the floor of the receiving building. When MWP is needed by the process- ing line, the bales could be manually cut open as the paper is fed into the receiving hopper. The remainder of the process would be identical to that discussed for the pre- vious three methods. Processing Location The possible locations for processing MWP for use as fuel are the recycling collector's facility, the industrial end-user’s facility, and a special processing facility separate from the collector’s or end-user’s facilities. Processing at a combination of locations may also be feasible. The number and location of the processing facilities will depend on various techni- cal and economic factors, one of the most significant being the demand for and the quantity of MWP fuel produced. If demand is high and large amounts of the MWP are needed, a central processing facility supplying numerous uses may be practical. On the other hand, if few facilities use the processed MWP, a central processing facility may be economically unfeasible. Processing at a separate facility located apart from the MWP supplier and end-user has several disadvantages. Since the MWP would have to be transported to the process- ing facility and subsequently transported to the end-user, handling and transportation Costs will likely be higher. The increased costs of owning and operating a separate facility must also be considered. However, a special processing facility will likely benefit from economies of scale and may be the preferred choice when insufficient space is available at other potential processing sites. Processing at a separate facility also carries the advantage of decreasing the impact on the seller’s or buyer’s existing operations. It may be possible to mix MWP with the end-user’s conventional fuel before the fuel is delivered, thereby eliminating the need for changes in on-site fuel processing methods. For example, the fuel supplier could deliver a specified blend of pelletized MWP and coal. Processing will most likely occur at a combination of locations, with the fuel sup- plier and fuel user working together to minimize the overall costs of handling and processing. For purposes of generic assessment, it is assumed that a centralized processing facility is constructed. The facility would be located near existing MWP sellers and contain equipment to receive, store, shred, pelletize, store the shredded and pelletized products, and load the processed MWP into vehicles for hauling to the end-user. The MWP processing facility would likely receive its material in bales, the same form in which it is sold on existing MWP markets. Costs for constructing and operating the processing facility will be covered by the price spread between the “as collected” MWP and the processed MWP. The costs for constructing, operating, and maintaining the processing facility and the resultant price for processed MWP are discussed below. Processing Costs Cost estimates have been prepared for a central processing facility as described above. Both capital costs and annual operating and maintenance costs have been es- timated in 1991 dollars. Costs for the processing facility were developed with the assumption that the facility would be capable of producing 5 tons per hour of shredded MWP and 10 tons per hour of pelletized MWP 24 hours per day, 5 days per week. Since the MWP is shredded prior to pelletizing, the shredders are sized for 15 tons per hour throughout. Storage must be provided for MWP at each processing stage to allow for equip- ment downtime and variations in receiving and shipping. Additional equipment re- quirements include conveyors and fire protection equipment. Tables 9 through 11 contain a summary of the facility capital and operating costs, including an estimate of the costs for the shredded and pelletized products. Projected processing costs are $12 per ton for shredded paper and $30 per ton for pelletized paper. The actual design and operation of the processing facility will depend on which facilities contract for processed MWP. It is assumed that these processing costs would apply regardless of the actual size or throughput of the processing facility. Table 9 Central MWP Processing Facility Capital Costs (1991$) (1) Item Capital Cost Conveyors $ 206,500.00 Shredders 386,500.00 Pelletizers 550,000.00 Storage Equipment 130,000.00 Rolling Stock 110,000.00 Building & Misc. (2) 1,458,500.00 SUBTOTAL $2,841,500. State Sales Tax @ 8.1% 230,000.00 Engineering @ 10% 284,000.00 Contingency @ 10% -284,000.00 TOTAL FACILITY COST $3,639,500.00 (1) Facility designed for throughput of 5 tons per hour shredded MWP and 10 tons per hour pelletized. (2) Does not include cost of land. Table 10 Central MWP Processing Facility Operations & Maintenance Costs (1991$) (1) Item Annual Cost Labor (2) $860,000.00 Maintenance 250,000.00 Electricity 220,000.00 Other Utilities 75,000.00 Insurance ~75,000.00 TOTAL $1,480,000.00 (1) Assumes facility operates 24 hours per day, 5 days per week, 50 weeks per year (2) Labor costs include benefits 20 Table 11 Central MWP Processing Facility Processing Cost Summary (1991$) Facility Capital Cost Amortization 10 years @ 10% interest $ 592,000.00 Facility Operations & Maintenance 1480.000.00 Total Annual Costs $2,072,000. MWP Throughput, tons per year (1) Shredded (5 tons/hour) 30,000 Pelletized (10 tons/hour) 60,000 Projected Processing Costs, $/ton (2) Shredded 10 Pelletized 30 (1) Throughput assumes plant operates 24 hours per day, 5 days per week, 50 weeks per year. (2) Processing costs are derived by dividing total annual costs by MWP throughput and by allocating costs between the shredded and pelletized product. Transportation Materials collected in residential recycling programs are usually delivered to a processing facility where they are separated from other recyclables (if necessary) and prepared for market. At the processing facilities, MWP is typically baled in prepara- tion for market. The following section discusses the regulations, transport vehicles, loading and unloading requirements, and costs associated with transporting MWP from the seller to the facility where it will be combusted. Regulations Affecting Transportation Washington State regulations for vehicle sizes, weights, and loads are set forth in RCW 46.44. Maximum sizes are 8-1/2 feet wide, 14 feet high, and 75 feet long. Allow- able vehicle weights under normal conditions depend upon the configuration of the vehicle. Cities and counties may also place weight and size limitations on roads which fall under their jurisdiction. Washington Utilities and Transportation Commission (WUTC) tariffs would apply for transport of waste paper by common carriers. MWP fuel could be classified as a waste paper, a solid waste, or possibly as a wood residual. WUTC tariffs do not apply to the transport of materials in company-operated vehicles when the vehicles are used only to haul materials for the company. The impact of WUTC tariffs on hauling costs are discussed below. Special transportation regulations which would apply over certain haul routes will be evaluated as part of the site-specific analysis. These regulations could include weight and size restrictions imposed by local jurisdictions, special WUTC tariffs, and other regulations which could be imposed to mitigate traffic impacts. Transport Vehicles MWP is typically transported to market by truck. Railroad transport could best serve the needs of some users, but will not be covered in the generic analyses. Several types of trucks are suitable for hauling MWP: dump trucks, live-bottom trailers, conventional enclosed semi-trailers, flatbed trailers, and hopper bottom trucks. Selecting the appropriate truck type depends primarily upon how the waste paper is prepared prior to shipment, the type of loading and unloading facilities, and haul dis- tance. Hopper bottom trucks can only be utilized for hauling waste paper which has been pelletized, and are the preferred mode of transport for this type of material. Hopper trucks are loaded from the top by mechanical or pneumatic conveyors and unloaded through the bottom. Flatbed trailers can be used to haul bales, but the bales must be covered to prevent littering along the haul route and to keep the bales dry. Conventional enclosed semi- trailers are more commonly used to haul baled waste paper, offering better protection along the haul route but less access to the payload for loading and unloading. Stand- ardized intermodal freight containers are also commonly used for hauling bales. Enclosed trailers and containers can also haul bulk MWP. Bales are typically loaded and unloaded with forklifts, while bulk loads can be handled with front-end loaders (for loading and unloading) and truck dumps (which employ a hydraulically powered platform to tilt the entire truck, or just the trailer, for unloading). Dump truck/trailer combinations and live-bottom trailers typically haul bulk loads and have the advantage of being able to dump onto storage piles without additional equipment. Live-bottom trailers have moving floors which unload the payload through the rear of the trailer, usually in about ten minutes. Dump truck/trailer combinations have smaller capacities and are favored for shorter haul distances. oading/Off-Loading Requirement Loading and off-loading requirements depend upon how the waste paper is prepared and the type of transport vehicle. Baled MWP is generally loaded and un- loaded with forklifts, with the bales stacked for storage. Bulk loads of pelletized waste paper are loaded and unloaded with mechanical or pneumatic conveyors and stored in silos or sheds. Bulk loads of shredded or unprocessed MWP are typically loaded by front-end loaders, but could also utilize conveyors, or push-blade compactors. One possible load- ing arrangement is to have an open-top trailer below the floor, with the waste paper pushed in from the floor above. Live-bottom trailers and dump trucks/trailers unload into piles. Truck dumps can be used to unload bulk loads from conventional enclosed trailers into piles. Live-bottom trailers can be used to meter controlled quantities of waste paper toa processing or fuel feed system. In this case, live-bottom trailers can serve as the storage and metering needs of the end user or processing facility. In a similar way, live- bottom receiving hoppers can store and meter waste paper as required by the next processing step. MWP collected in residential recycling programs is typically baled and shipped overseas in intermodal shipping containers. MWP which would be processed and util- ized as fuel by industrial end-users would likely be received at the processing facility in baled form, although alternate arrangements could be made with suppliers. Shredded MWP The receiving and off-loading requirements for shredded MWP are highly site- specific. Shredded MWP could be unloaded directly into the existing fuel receiving system for the wood fired combustor types. If the two fuel feeds are not compatible, for instance, if the existing fuel undergoes processing between the point of receipt and combustor injection, and it was determined that inclusion of shredded paper would hinder this processing, the shredded MWP would be conveyed to a point in the plant fuel feed system where it could be combined with the existing fuel. Discussions with plant personnel would lead to a determination of storage and feeding requirements. An important criterion would be operator control over the combustion process, as was dis- cussed previously. 22 Pelletized MWP A similar situation as for shredded MWP would apply for the receipt of pelletized MWP and its off-loading requirements. The advantages and disadvantages would be the same with the additional disadvantage stemming from the increased handling of the pelletized fuel. The more the pellets are handled, the more they will tend to disin- tegrate, resulting in more dust generation in the material handling system as well as more fines injection into the combustion chamber. Also, the pellets will become dryer over time, further aggravating the situation. “ 79 In this case, MWP received at the plant site would be in the same condition as it was collected. The paper would be deposited on the floor or dumped directly into the hopper in the receiving building. Consequently, the material handling system concept is based on the initial feed input being loose, unprocessed paper. : If the plant is located some distance from the paper collection area, the paper may be compacted either by baling or with compactor trucks for transportation and delivery. The compactor truck would deposit its load on the floor, where it would ex- pand or loosen as it is fed into the receiving hopper. If paper is delivered in bales, the bales would be manually cut open as the paper is fed into the receiving hopper. The paper would be moved from the floor of the receiving building to the receiving hopper by means of a small front-end loader. The advantage of this method of receiving would be its adaptability to the widest range of sources of supply. As discussed previously under “Processing Methods,” it is possible that the MWP could be fed directly into the existing fuel receiving system. Otherwise, some variation of the system described here may be required. Baled MWP The requirements, advantages, and disadvantages of receiving the MWP in this condition have previously been discussed. To summarize, the baled MWP requires less room for storage. Another advantage is that it is compatible with receiving material in the “as collected” condition. A disadvantage is the somewhat increased han- dling costs associated with the need to break open the bales for introduction of the MWP into the materials handling system. Care must also be taken that the strapping material does not become mixed with the MWP. ‘Transportation Costs Tariffs imposed by the WUTC depend on many variables, including the origin of the material, the destination, the size of the load, type of equipment, the physical state of the load, the classification of the load (whether a waste product or a fuel, for ex- ample), and the nature of the loading and unloading facilities. Typical tariffs for MWP hauling range from 7 to 40 cents per ton per mile. Table 12 provides planning-level estimates of hauling costs for transporting MWP to-the steam plant in company-owned vehicles. These costs include operation, main- tenance, depreciation, and allocation for backup vehicles. The actual cost can vary sig- nificantly based on haul length, load size, vehicle configuration, and road conditions. Table 12 Planning Level Transportation Costs One-Way Typical Annual = Typical Annual Haul Distance Transportation Cost Haul Cost Haul Cost (miles) (SAon/mileXS$Aon) @ 50 tpd @_250 td up to 13 $0.67 $4 $ 77,000 $ 385,000 13 to 26 0.31 6 97,000 485,000 26 to 38 0.18 6 95,000 475,000 38 to 60 0.16 8 129,000 647,000 60 to 100 0.13 17 279,000 1,394,000 Handling and Storage Considerations P Handling at th mbusti cil MWP handling at the combustion facility will consist of unloading, storing, and reclaiming the MWP fuel. A separate MWP fuel feed system would then feed the MWYP into the combustor at a controlled rate. A simple method of on-site MWP handling consists of storing the MWP in live- bottom trucks and unloading at a controlled rate into the fuel feed system. Larger and more complex facilities would likely require unloading systems, storage facilities, and several conveyors. Facilities presently fueled by gas or oil will likely require additional operations staff to handle MWP fuel. Facilities which already handle solid fuel will likely be able to handle MWP fuel with fewer operational changes and can probably get by with ex- isting staff. Storage facilities are necessary at the processing facility and end-user to ensure an adequate supply of waste paper to accommodate delivery variations. Typically, storage for at least one days’ fuel consumption should be provided at the combustor. Waste paper can be stored in silos, bunkers, bale stacks, in bulk piles, and in a truck trailer queue. Outdoor storage (except for enclosed truck trailers) is not practical due to blow- ing debris, dust migration, and moisture problems. ations Affecting St in, The most significant regulations affecting storage and processing are those that re- quire fire suppression systems. These systems and the buildings they are housed in would have to conform to the requirements of the Fire Marshal of the local jurisdiction and applicable fire codes. The 1988 Uniform Fire Code (UFC) specifies that a permit is required to store or handle combustible fibers in quantities in excess of 100 cubic feet (section 4.108c.4). Baled waste and baled wastepaper are defined as combustible fibers (section 9.105). Storage of loose combustible fibers (not baled or packaged) in excess of 1,000 cubic feet is required to have automatic sprinkler system protection, and baled storage must be in piles of less than 25,000 cubic feet separated by aisles or by fire barriers (section 28). At least three feet of clearance shall be maintained between the tops of storage * piles and sprinkler heads. Additional UFC requirements are identified in section 81 for storage of combustible materials in high piles (generally higher than 15 feet). The UFC also specifies that processing equipment and structures should be designed to minimize dust generation and accumulation. Methods of accomplishing this include dust collection systems near the point of generation, covering flat surfaces 2r 24 with sloped covers to discourage dust accumulation, and regular dust removal by housekeeping personnel. Other applicable regulations include litter control requirements (which would not be a problem in enclosed buildings), air pollution control requirements for dust preven- tion measures and dust collection (WAC 173-400-050 (3) and (8)), and worker-safety regulations. Description of S Facilit Storage facilities must keep the waste paper dry. Wet waste paper may cause severe handling and processing difficulties and will not bum as well. Wet pellets tend to swell and disintegrate. Probably the simplest method of storage is to keep several trailer loads of waste paper on hand, unloading them into the processing or fuel feed system as necessary. In this case, loaded trailer bodies are left at the combustor while the driver takes an empty trailer for additional collection. With live-bottom trailers, this method is even more attractive, since the waste paper can be metered out of the trailer as needed. This method likely minimizes the impact of adding storage capabilities to an existing facility, and is particularly suitable for pilot programs. The disadvantage of this method is that extra trailers are required to account for those that are used temporarily as storage, resulting in additional expenses. The cost of a live-bottom trailer is es- timated at $40,000. Concrete bunkers and concrete/steel buildings can be constructed to store bulk waste paper. Storage buildings typically have concrete walls up to a height of at least six feet to help contain the storage pile and protect the building from damage from moving equipment. Silos are typically the most expensive storage method, but are the preferred method for storing pelletized fuels. For non-pelletized MWP, material storage will be facilitated if paper is received either compacted in bales or in compactor trucks. Costs of Handling Storage Facilities Material storage at the central MWP processing facility has been included as a cost of the facility and previously described in the processing section above. Costs for storage facilities and fuel handling are shown in Figure 9. At combustors which consume less than three to four tons per hour of MWP, on-site fuel storage in live-bottom truck trailers appears to be the best storage method. At feed rates above four to five tons per hour, buildings designed for receiving and handling the MWP fuel are preferred over trailer storage. Whether a specific facility is better suited for trailer or building storage will depend on many Site-specific cost factors. tion Equipmen “ Selection of MWP/Conventional Fuel Ratio The co-firing of MWP with more conventional fuels such as wood, coal, oil, and gas requires that the ratio of the MWP to the primary fuel be limited in order to main- tain steady operating characteristics at the facility. The primary area of concem is the bum rate/heat release in the combustion zone itself. The heating value of the MWP will differ from that of the primary fuel. Consequently, an upper limit must be estab- lished on the ratio of the MWP fuel to the primary fuel so that the total heat release in the combustion chamber does not vary to the extent that production of steam for an in: dustrial use such as cement production is adversely affected. 26 MWP Storage and Fuel Handling Costs $25 0 2 4 6 8 10 MWP Throughput, tons/hour Note: Switchover from truck trailer to building storage occurs between 3 and 4 tons/hour MWWP thoughput | —*— No additional staff + .5 additional staff —*—- 1 additional staff | Figure 9 Another area of concem is the physical characteristics of the MWP itself. Loose paper will have a tendency to float in the fumace area. Depending upon the type of processing done during the material handling stage, such as degree of shredding and densification, loose paper char can rise in the boiler and be carried into the boiler tubes and beyond into the emissions control equipment. An excess amount of this can lead to difficulties caused by. plugging and accumulation of material on the boiler tubes themselves. The wide variation in the ash content of the MWP with an average value three times that of some coals or hog fuel may exceed the capacity of the existing ash handling system. Finally, the chemical properties of MWP differ from that of conventional fuels. The chloride content of the MWP may lead to the formation of hydrochloric acid within the combustion chamber which is corrosive to the boiler tubes. Other chemicals in the MWP resulting from the paper manufacturing process and from the ink used in the printing process will affect the chemical composition of the ash coming from the combustion chamber. In summary, sound operating practice dictates that the ratio of MWP to conventional fuel be limited to prevent problems from occurring in these areas discussed. , Retrofit Requirements Retrofit requirements are highly site specific. The previous discussion of process- ' ing methods described the equipment requirements for preparing the MWP to be used as a fuel in various combustor types. The discussion in this section will consider only the retrofit requirements for the combustor and ash handling system. The more properties that MWP fuel and the fuel it displaces have in common, the simpler the retrofit requirements will be. Combustor types which currently bum a solid fuel are therefore generally better suited for conversion to waste paper fuel firing. As a result, conversion requirements for solid fuel combustors are less complex than for oil- rt 26 and gas-fired boilers. However, facilities which consume liquid or gas fuels generally have higher fuel costs than those utilizing wood waste, so additional modifications may be justified in order to use a low cost fuel such as MWP. Regardless of the combustor type, many site-specific factors must be evaluated before conversion requirements can be determined. These factors include: + The capability of the furnace with regard to ash removal. Mixed paper fuel like- ly contains more ash than the fuel it would replace. + The impact that buming waste paper fuel will have on heat release rates and gas velocities. ¢ The adequacy of the intemal fuel feed and stoking system. + The boiler’s tube spacing with regard to increased ash and soot loading. Spacing should be evaluated to ensure minimal ash fouling and plugging and permit ef- fective soot blowing. + A review of soot blower capabilities. + The air pollution control system’s ability to handle increased flue gas ash load- ing and still meet emissions requirements. + The potential need for major modifications for an air pollution control system in order to meet existing permit standards or a new, stricter standard required by pemmitting agencies triggered by the change to MWP fuel. + The ability of the existing ash handling and storage systems to remove addition- al quantities of bottom ash and fly ash. + The amount of space available for additional systems and storage requirements. Pollution Control There are three primary ways in which air emissions regulations could affect the feasibility of combusting MWP fuel at an existing facility. Assuming that air emissions permit requirements and regulations remain un- changed after switching to MWP fuel, the operator must ensure that existing permit conditions are not exceeded due to firing MWP. This assumes that retrofit work, if any, for the addition of MWP firing capacity does not trigger a definition of the facility as a “new source,” “modified source,” or “new construction,” and that the change in fuel does not trigger changes in permit requirements. If the retrofit work required for using MWP fuel requires changes sufficient to re- quire a new or revised air permit, then a new permit must be secured. The new permit may Contain more stringent emission standards than the previous one the facility operated under. If the facility is subject to a BACT review under PSD regulations or must comply with NSPS for a specific source Category, the new permit is likely to con- tain stricter standards. If MWP is classified as a solid waste, the facility would be subject to solid waste incineration regulations, which have more stringent emission standards than industrial boilers and process equipment. n uipment ui nt Pollution control equipment requirements and costs will vary according to what ex- isting equipment is installed and depending on the air emissions permit requirements. We have assumed that a particulate collection device will be required and have specified an electrostatic precipitator for this purpose. Bag houses may be the 27 7? preferred particulate collection device based on facility design, emissions, and cost considerations. Costs for electrostatic precipitators and baghouses are roughly the same at the level of detail use in the planning cost estimates. Other equipment, such as acid gas scrubbers and NOx controls may be required pursuant to a BACT review. Economic Considerations The economics of using MWP as a fuel at a given facility will depend on facility retrofit costs, changes in operation and maintenance costs, and competing fuel costs. These conditions will form the basis for what a facility would be willing to pay for MWP, with the bottom line being that the switch to MWP result in a net savings to the facility. For a manufacturer, the economics of producing MWP fuel will depend on the cost of production and the price at which the fuel can be sold. The economics of producing a MWP fuel will also depend on whether the existing overseas market will continue, or whether MWP assumes a negative value as a result of disposal costs. Figure 10 presents an array of competing fuel costs. The value of the various fuels are presented in dollars per million Btu (MBtu) equivalent to allow for comparisons, and assumes a $30 and $12 per ton processing cost, respectively, for MWP pellets and MWP fluff. As shown, if MWP has a processing cost of $30 per ton ($2.10/MBtu), it would not be competitive with either hog fuel or Black Diamond coal which are cur- rently valued at $1.15/MBtu and $1.40/MBtu, respectively. MWP would, however, be competitive with Utah coal or natural gas at this price. Of course, none of these com- parisons consider the added cost to a facility to allow it to bum MWP fuel, which in the case of a natural gas power plant retrofit, would be considerable. While the value of MWP fuel to an end-user will be determined by site-specific costs, a MWP fuel processor needs to consider the value of MWP within the context of other markets. Figure 11 shows the sensitivity of MWP fuel price, for both pellets and fluff, as a function of avoided disposal costs or export benefits. As shown, if there is no export market for the MWP and the alternative is disposal, break-even costs for the manufacture of MWP fuel become less as the avoided disposal cost or tip fee in- creases. Conversely, if a strong export market for MWP exists, the cost a manufacturer would have to charge for MWP fuel would increase. For example, if it cost $20 per ton to dispose of MWP, a MWP fuel processor would have to sell MWP pellets at $10 per ton in order to recover his processing costs. On the other hand, if MWP had a secondary fiber market value of $10 per ton, a MWP fuel processor would have to receive $40 per ton for MWP pellets to break even. Mixed Waste Paper: Competing Fuel Costs ao $/MMBtu Equivalent MWP Pellet MWP Fluff Hogfuel B.D. Utah Coal Natural Gas Competing Costs Figure 10 Breakeven Cost for the Sale of MWP Fuel as a Function of Export Market and Disposal Costs MWP Breakeven Sale Price, $/ton 30 20 410 Tipping Fees Avoided Costs, $/ton Expott Price —* Fluff@ $12fAon -+- Pellets @ $30fon | Figure 11 29 Site Specific Feasibility Studies To realistically evaluate the feasibility of using MWP as a fuel, three facilities were selected for individual study: Ideal Basic Industries, Weyerhaeuser-Longview, and Westem State Hospital. These facilities were chosen for specific analysis based on the following criteria. 1. Minimize Conversion Costs *existing pollution control equipment. *existing solid fuels handling ability. *sufficient storage and receiving space. *minimal fuel switching impacts on boiler operations. *minimal ash disposal requirements. 2. Maximize Value of Fuel *proximity to MWP supply. *value of fuel displacement savings. 3. Institutional Constraints *replicability of study to other similar facilities. *willingness of study candidate to participate in the study. *familiarity of study candidate with altemative fuels. *ability of study candidate to implement retrofit. The following section describes the aforementioned facilities, discusses the techni- cal issues affecting the feasibility of using MWP fuel, and provides an economic com- parison of MWP fuel and conventional fuels for each facility. S f Site-Specific Feasibility Studi A summary of the three site-specific studies is presented in Table 13. As indicated, if MWP is classified as a fiber fuel, Weyerhaeuser Paper Mill and Wester State Hospital could pay up to $19 per ton for MWP fuel and break-even; while Ideal Basic Industries could purchase MWP for as much as $5 per ton, delivered. Of course, for MWYP fuel to be attractive, it would have to be available at a cost below the break-even values given for each facility. If, however, MWP is classified as a solid waste as described under the proposed amendments to the Clean Air Act, both Weyerhaeuser and Wester State would need to add acid gas control technology to their operations. At an added capital cost of $8.8 and $2.4 million dollars, respectively, the correcponding break-even price for MWP drops to a negative $42 per ton for Weyerhaeuseer and a negative $23 per ton for Wester State. The economics at the Ideal Basic cement kiln would not be affected by a change in classification due to the inherent gas scrubbing effect of the cement making process. Table 13 Site-Specific Summary Ideal Basic Wester State Industries, Hospital, Seattle Steilacoom Combustor Description Cement Kiln Spreader Stoker & -Fired Boilers Existing Fuel Pulverized Coal Natural Gas; Wood Pellet backup Air Pollution ESP; cement-making No system; some fly Control System process tends to scrub ash collected by acid gases baffles Annual Average Heat 340 20 Input (MBtu/hour) MWP Fuel Ratio 10% (shredded) 100% (pellet) Average Daily MWP = 58 34 Consumption (tons/day) Total Retrofit Capital $475,000 $1,334,000 Cost (1991$) Break-Even Cost of MWP ($/ton) as a fiber fuel $5 $19 as a solid waste $5 $(23) al Basic Industries, Inc. Facility D os Weyerhaeuser Paper Longview Spreader Stoker Boiler Hog Fuel (with up to 20% coal) Multiclone, Electroscrubber rock scrubber & baghouse 800 20% (pellet) 171 $72,000 $19 42) The Ideal Basic Industries’ cement kiln is located in Seattle on the Duwamish Waterway and produces approximately 450,000 tons of Portland cement annually. The kiln was installed in 1967, has refractory lining, and measures approximately 14 feet in diameter by 500 feet long. The kiln operates continuously except for 25 days per year down time for main- tenance. With the high temperatures, long production process, and many other vari- ables which could negatively impact the quality of the clinker, the best strategy is to operate continuously and change as few variables as possible. Since ash from the com- bustion process becomes part of the clinker product, the formulation of the raw material slurry must consider the type of fuel being used. For these reasons, fuel must be fed at a uniform rate and constituency. The Ideal Basic cement kiln consumes approximately 325 tons per day of coal, or about one ton of coal for each 4.5 tons of clinker produced. Based on tests of RDF at other cement kilns, a MWP fuel ration of 30 percent should be feasible at Ideal Basic. However, staff members at Ideal Basic stated that they would prefer using a 10 percent MWP fuel ratio. MWP Retrofit Requirements The Ideal Basic cement kiln offers several significant advantages which serve to minimize the amount of retrofit work which would be required to use MWP fuel. These advantages are: + Existing air pollution control equipment and air pollution operating permits should allow MWP fuel use without significant changes. The permit levels are maximum 5 percent opacity over a one hour average, maximum 20 percent opacity over a three minute average, and 0.05 grains per dry standard cubic foot. Emissions have never come close to exceeding these limits, according to Ideal 31 Basic. The facility currently operates well below permit levels. Furthermore, the buffering effects of the lime will offset the need for acid gas scrubbing equip- ment if the MWP is characterized as a solid waste. Although a new pemmit would be required by the fuel change, Ideal Basic is familiar with the process and has not experienced problems in the past. + The facility is located close to waste paper collectors and brokers. ¢ Ash disposal would not be an issue since the ash is largely incorporated into the clinker. + The facility could use shredded or fluff MWP fuel as opposed to a densified fuel pellet. Critical I The following issues have been identified as critical when considering MWP as a supplemental fuel at Ideal Basic: + The quality of the end product must not suffer. No savings in fuel costs can jus- tify a reduction in product quality and the resulting loss of business. The success- ful implementation of RDF as a supplemental fuel at similar cement kilns indi- cates that quality would not suffer when firing MWP, which is a cleaner fuel than RDF. + MWP must combust quickly and consistently to maintain the 2,800°F tempera- ture in the combustion zone and to prevent starvation and cool spots in the kiln. The MWP infeed must be steady and controllable. « The successful implementation of RDF at other facilities indicates that this is a manageable issue. Proper design of the feed mechanism and its controls is neces- sary. « Asteady supply of MWP must be guaranteed so that Ideal Basic is not forced to make operational changes. + A steady supply of MWP is being generated in the state. Long-term contracts with paper brokers and processors should provide sufficient security for Ideal Basic. : + Chlorine present in the MWP must not adversely affect the air pollution control equipment by reducing the effectiveness of the ESP or corroding the ESP or other components. At the 10 to 30 percent MWP feed rate, the already low chlorine content of the MWP will be diluted to an even lower level, on the order of 0.009 to 0.03 per- cent. This low level of chloride plus the high exit gas temperature which is above the condensation point of hydrogen chloride, precludes any problems to the ESP from chloride. Test reports on RDF (a material whose chloride content is much higher than that of MWP) co-firing in cement kilns has confirmed that corrosion or clogging are not the problem. ¢ The buming of MWP fuel must be acceptable to the community. Ideal Basic does not want to be the subject of any community protest, especially one which labels them a “garbage bumer.” Ideal Basic has stated they would not bum MWP fuel if it becomes a public issue. MWP which is collected separately from garbage and processed for use as a fuel will not likely be considered “garbage” by the public. On the other hand, people who have source separated their MWP for recycling programs may feel that burning the MWP is not the same as recycling it. Since it will be used at an exist- ing operating facility, public opposition to MWP fuel use is not expected at Ideal Basic. Classification of MWP fuel as a “fiber fuel” rather than a “solid waste” will help in this respect. 32 E ic Analysi Ideal Basic buys its coal for approximately $1.2/MBtu (delivered to their facility) and forecasts that the price will decrease over the long term. Ideal Basic expects to pay approximately $1.1/MBtu on their next contract, which they expect to negotiate in the next two years. Ideal Basic has stated that MWP fuel would have to cost less than 50 cents/MBtu (all costs considered) to provide sufficient incentive for them to consider using it. Table 14 summarizes the incremental annual costs (including amortization of the capital costs, and operations and maintenance costs) for using MWP fuel. As shown, the price Ideal Basic could pay for MWP fuel would have to be $5 per ton to break even. If MWP is classified as a solid waste, these costs would likely remain the same since the cement making process scrubs acid gases and the existing particulate collec- tion device should meet emissions requirements for the combustion of solid waste. w State Hospital Boiler. Stei cili cript Westem State Hospital is a psychiatric hospital operated by the State Department of Health and Social Services. The facility has approximately 1,200 patients. Steam is used for space heating, water heating, and in the laundry facility, which represents the largest steam user at the hospital. The laundry is operated eight hours per day, five days per week. The overall steam load varies from approximately 250 million Btu per day in the summer to approximately 900 million Bru per day in the winter. The steam plant consists of three boilers housed in a concrete structure which was built in the 1920s. The boilers are: Boiler #1: small, natural gas-fired; used in summer only. Boiler #2: large, natural gas or solid fuel-fired (spreader stroker); used rest of year. Boiler #3: large, solid fuel only (spreader stoker); used as backup boiler. The facility originally burned coal. In 1979, after it became apparent that buming coal was violating air emissions requirements (by exceeding the opacity regulations), wood pellets were substituted. At this time, additional solid fuel storage capacity was added so that 1,100 tons of wood pellets could be stored in overhead bins, in addition to the 200 tons which can be stored in the fuel delivery system. As the price of natural gas fell in the 1980s, it became more economical to burn gas than the wood pellets. Supply problems (a lack of sufficient on-site fuel inventory) with the wood pellets also contributed to the switch to natural gas. Currently, the hospi- tal purchases “transportation gas” for approximately 35 cents per therm ($3.5/MBtu) . P Retrofit Requirement: The retrofit requirements focus on the air pollution control equipment and struc- ture changes to the powerhouse. Since the facility already handles fuel pellets similar to the MWP fuel pellets, no substantial changes are Tequired with fuel receiving, storage, and feeding system, or with the boiler itself. The existing stack components could physically be used when firing MWP pellets. However, a switch in primary fuel may be considered a major modification of an exist- ing air emissions source. Since the facility would undergo a major modification, it would therefore be subject to permitting requirements as if it were a new source. 33 Table 14 Derivation of MWP Fuel Value Ideal Basic Industries Cement Kiln (Base Case) Combustor Characteristics: Existing Fuel Coal (pulverized) Fuel Heat Input, MBtu/hour 340 Operating Schedule, _ hrs/day 24 days/year 340 MWP Fuel Ratio 10% Assumed Fuel Characteristics: Coal MWP (shredded) Higher Heating Value, Btu/lb 12,500 7,000 Ash Content 4% 10% Cost (delivered to user), $/ton 30 Cost per Million Btu $1.20 Assumed Ash Disposal Parameters: Cost/Ton Tons/Year Current, Buming Coal n/a n/a Future, Co-Firing MWP (1) n/a n/a MWP Retrofit Capital Costs (1991$) Receiving and Fuel Feed 7 live-bottom truck trailers $280,000 Shed & pit with sump pump 10,000 Unloading equipment 100,000 Feed equipment 70,000 Piping 5,000 Controls 10,000 Combustor Equipment 0 Air Pollution Control Equip (2) 0 Ash Handling Equipment 0 Total Capital Costs $475,000 Annual Cost Calculations (1991$) Retrofit Equipment Amortization (3) ($78,000)— net sh CD Incremental Operations & Maint. ‘ (149,000) Fuel Handling (4) (149,000) — Air Pol. Control Equip. (2) 0 Other 0 Incremental Ash Disposal Cost n/a Conventional Fuel Consumption Avoided 332,928 Annual Savings (Cost) $105,928 Break-Even MWP Price Calculation “MWP Fuel Consumption, tons/year 19,800 Break-Even Cost of MWP, $/ton $5 (1) Assumes additional ash is incorporated into the clinker. (2) Assumes no additional air pollution control equipment is required to co-fire MWP fuel. (3) 10 year level amortization at 10% interest rate. (4) Assumes one additional operations staff each shift required for MWP fuel handling. 34 Installation of an air pollution control system at the facility is made difficult by the lack of available space within the building and the age of the structure. Due to the age and uncertain structural stability of the existing stack, modifications will require the ad- dition of a new electrostatic precipitator (ESP) located on the roof due to the age of the facility. Structural support to the roof must also be provided to accommodate the air llution control equipment. The estimated cost for performing these modifications is 1,274,000. If an acid gas scrubber is required to comply with proposed solid waste combustion regulations, the estimated retrofit cost rises to $3,714,000. Critical | The following concems were raised by hospital personnel: « Hospital personnel expressed concem that the MWP pellets be compatible with the existing fuel handling system. The existing system works well with coal and wood pellets; if changes are required, the system should still be able to use coal and wood pellets. + A 3/8 inch pellet will flow easily within the existing system and has the highest degree of acceptance at the facility. A slightly larger pellet (1/2 inch) may also be suitable; this larger pellet size could be tested after initial acceptance. + Combustion with MWP must be as reliable as with conventional fuels. Ade- quate MWP supply must be guaranteed so that fuel does not have to be switched due to lack of supply. Hospital personnel have stated that the existing solid fuel combustion system is as reliable as the natural gas system. The MWP system should experience similar reliability. The addition of the air pollution control system will add some complexity to the operation, however. The hospital has had difficulties keeping solid fuel inventory levels at acceptable levels when a wood pellet supplier failed to maintain an acceptable fuel inventory on-site. The hospital does not want to encounter similar situations with MWP fuel. « MWP combustion must not have long-term adverse impacts on the boiler. Abrasion, soot buildup, slagging, efficiency loss, and decreased boiler life are concems. E ic Analysi ; Wester State Hospital buys its natural gas for approximately $3.5/Btu (delivered). All other things being equal, MWP fuel would have to cost less than natural gas ona - heat input basis to account for the increased operations and maintenance costs required by the solid fuel. MWP must also provide enough economic incentive to pay back any required retrofit costs. Table 15 summarizes the incremental annual costs (including amortization of the capital costs, and operations and maintenance costs) amortization of the capital costs, and operations and maintenance costs for using MWP fuel. In order to become economically attractive to the hospital, the price for MWP pellets would have to be less than the break-even price of $14 dollars per ton. The above cost discussion assumes that MWP is considered a fiber fuel. If MWP is considered a solid waste, additional air pollution control equipment to meet the stricter emissions requirements for solid waste incinerators would be required increasing the retrofit cost to approximately $3,736,000. The corresponding break-even price for MWP would drop dramatically as a result of these costs to a negative $23 per ton. Also, ash disposal costs could rise if the ash must be disposed according to regulations for ash from the combustion of municipal solid waste. 35 Table 15 Derivation of MWP Fuel Value Wester State Hospital (Base Case) Combustor Characteristics: Existing Fuel Natural Gas Fuel Heat Input, MBtu/hour 20 Operating Schedule, _ hrs/day 24 days/year 365 Assumed Fuel Characteristics: Natural Gas Higher Heating Value, Btu/lb — Ash Content — Coal (delivered to users), $/ton — Cost per Million Btu $3.50 Assumed Ash Disposal Parameters: Cost/Ton Current, Buming Natural Gas n/a Future, Co-Firing MWP (1) 30 MWP Retrofit Capital Costs (1991$) Receiving and Fuel Feed 0 Combustor Equipment 0 Air Pollution Control Equipment Structural modifications $61,000 Remove existing stack 7,000 New stack, breeching, ducts 180,000 Fan 33,000 Switchgear 30,000 Wire and cable 12,000 Electrostatic precipitator 913,000 Boiler rental and hook-up 38,000 Ash Handling Equipment 60,000 Total Capital Costs $1,334,000 Annual Cost Calculations (1991$) Retrofit Equipment Amortization (2) Incremental Operations & Maintenance ; Fuel Handling (3) (62,700) Air Pol. Control Equip. (54,000) Other 0 Incremental Ash Disposal Cost Conventional Fuel Consumption Avoided Annual Savings (Cost) $ Break-Even MWP Price Calculation MWP Fuel Consumption, tons/year Break-Even Cost of MWP, $/ton MWP (pellets) 7,000 10% Tons/Year n/a 1,251 ($218,000) (116,700) (38,000) 613,200 240,500 [X] 12,500 [Y] $19 [X/Y] (1) Assumes the ash is considered a solid waste, not special incinerator ash (from the in- cineration of solid wastes). (2) Ten year level amortization at 10% interest rate. (3) Assumes 0.5 additional operations staff each shift required for MWP fuel handling. 36 Weyerhaeuser Boiler #11, Longview Facility Descripti Weyerhaeuser owns and operates a large kraft pulping mill on the Columbia River in Longview. Several boilers operate at the facility; MWP is being evaluated for use at Boiler #11, which is the largest boiler at the mill and also the only one which uses solid fuel. Boiler #11 was constructed in 1928 as a hog fuel boiler. In 1973, it was converted to bum a mixture of hog fuel and coal, with fuel oil backup. Boiler #11 typically produces 450,000 to 475,000 pounds per hour of steam, but has a maximum capacity of approximately one million pounds per hour. Total steam load at the facility is 1.7 million pounds per hour. The steam is used for electricity generation and for process functions at the mill. Weyerhaeuser has tested shredded waste paper at another boiler at their Longview facility. Some of the paper became entrained in the flue gases before combusting, resulting in singed paper being sent up the stack. Based on this and other experience, Weyerhaeuser personnel feel that shredded paper which has not been densified will present the following problems at Boiler #11: (1) the lightweight material will carry over into the air pollution control equipment, reducing its effectiveness or clogging the system (2) the low bulk density of the shredded paper will limit the amount of fuel energy which can be fed into the boiler, thereby reducing the boiler capacity. If a separate shredded paper pneumatic injection system, located below the existing spreaders, were used, the concems raised in item (2) could be mitigated. Weyerhaeuser is also aware of experience at Longview Fibre, where experience buming RDF from Tacoma showed that plugging and slagging problems should be ex- pected when firing RDF. Weyerhaeuser personnel believe that small MWP pellets (1/2 inch or 3/4 inch max- imum) would be suitable for Boiler #11. Pellets offer a practical bulk density for han- dling and feeding with the existing feed systems (without significantly decreasing the fuel feed capacity due to high volume feed requirements) and present a suitable par- ticle size for combustion close to the grate. MWP could be used in winter to offset the coal currently used to lower the moisture content of the hog fuel feed. In the summer, MWP could offset hog fuel consumption. P fi wi nt The retrofit requirements focus on a new storage and reclaim system for MWP. Changes to the existing fuel conveying system, the boiler, and the air pollution control system are not anticipated. As part of another project, Weyerhaeuser purchased two used silos and had them delivered in pieces to their facility. One of the silos has been erected and is currently used for coal storage (350 tons capacity). Pilings have been installed for the second silo adjacent to the existing coal silo. The second silo is suitable for MWP fuel storage and could be erected at a cost of $41,000, according to Weyerhaeuser. The existing coal unloading and storage system is suitable for use with MWP pellets, with the addi- tion of a diverter to direct the material to the coal or MWP silo, increasing retrofit costs to $72,000. MWP would be reclaimed from the MWP storage silo and fed on a new conveyor to the existing fuel feed conveyer. No changes are required for the existing fuel han- dling and feed system beyond the point where MWP is added to the fuel conveyor. The existing handling and feed system has the capacity to absorb the small increase in weight which would be required by adding MWP fuel pellets to the fuel mix. 37 If MWP is classified as a fiber fuel, the existing multiclones and electroscrubbers should preclude the need for additional air pollution control cau ment. Howevr, an acid gas scrubber would need to be installed if MWP is classi bed as a solid waste. The estimated capital cost of this retrofit is $8,800,000; annual operations and maintenance costs would also increase by an estimated $1,300,000. Critical [ The following concems were raised by Weyerhauser personnel: + Will the high ash content contribute to an increase in equipment erosion. + What will be the impact of dyes and paints in MWP on the boiler and will the inks cause corrosion problems. + What will be the effect of MWP on the existing scrubber. + Is there an adequate fuel supply of MWP, both daily and long-term. conomic Analysi Weyerhaeuser has indicated that their present cost of fuel is approximately 93 cents/MBtu. Overall costs for steam production at Boiler #11 are approximately $2/MBtu of steam energy. The company has indicated that the overall cost of generat- ing steam with MWP would have to be substantially below $2/MBtu in order for them to consider a fuel change. Table 16 summarizes the incremental annual costs (including amortization of the capital costs, and operations and maintenance costs) for using MWP fuel. In order to be considered an attractive option, the price for MWP pellets would have to be less than the break-even price of $19 per ton. If MWP is classified as a solid waste, high air pollution control costs will drop the corresponding break-even price for MWP to a negative $42 per ton, rendering the use of MWP totally unacceptable. Case Studies The use of MWP as a fuel has been considered elsewhere in the country, and in at least three cases, is receiving limited use. A brief profile of the three projects, located in Iowa, Wisconsin, and British Columbia, is presented below. Wastech Case Study Wastech Services LTD recently completed a pelletizer facility in Coquitlam, British Columbia, which uses post-consumer commercial mixed paper as its feedstock. The facility became fully operational as of August 1989, and is supplying paper pellets to CBR Cement-Tilbury Plant which co-fires the pellets with coal. Pellet production levels are not available from Wastech as they consider it Proprietary information at this time. Similarly, the price of the pellets is not available as Wastech and CBR are sharing the savings. The Wastech fuel processing plant receives MWP from contracted haulers who pick up a mixed commercial waste which contains a fair amount of plastics, corrugate, and mixed office paper. Wastech provides a rebate to haulers if they deliver a “cleaner” load and also encourage their commercial accounts to provide a “cleaner” supply. The mixed commercial waste is both hand and mechanically sorted at the plant with plastics (the plastics tend to degrade cube integrity) and corrugate pulled. No high grading of paper grades is done outside of the corrugate. 38 Table 16 Derivation of MWP Fuel Value Weyerhaeuser Hog Fuel/Coal Boiler (Boiler #11) (Base Case) Combustor Characteristics: Existing Fuel (1) Hog Fuel & Coal Fuel Heat Input, MBtu/hour 800 Operating Schedule, hrs/day 24 days/year 330 MWP Fuel Ratio (2) 20% Assumed Fuel Characteristics: Hog Fuel Coal (3) MWP (cubed) Higher Heating Value, Btu/lb 4,500 11,000 7,000 Ash Content 5% 5% 10% Cost (delivered to user), $/ton 10 38 Cost per million Btu $1. $1.73 Assumed Ash Disposal Parameters: Cost/Ton Tons/Year Current, Buming Hog Fuel & Coal $30 33,120 Future, Co-Firing MWP (4) 30 36,206 MWP Retrofit Capital Costs (1991$) Receiving and Fuel Feed (5) Erection of silo $41,000 Divertor, conveyor, misc. 31,000 Combustor Equipment 0 Air Pol. Control Equip (6) 0 Ash Handling Equipment 0 Total Capital Costs $72,000 Annual Cost Calculations (1991$) Retrofit Equipment Amortization (7) ($12,000) Incremental Operations & Maintenance (149,000) Fuel Handling (8) (149,000) Air Pol. Control Equip (6) 0 Other 0 Incremental Ash Disposal Cost (93,000) Conventional Fuel Consumption Avoided 1,094,000 Annual Savings (Cost) $840,000 Break-Even MWP Price Calculation MWP Fuel Consumption, tons/year 45,257 Break Even Cost of MWP, $/ton $19 (1) Fire 100% hog fuel in summer. In winter, mix 20% coal on a Btu input basis. The coal helps offset the higher moisture content of the hog fuel during the winter. . Coal is assumed to be mixed in at 20% for half of the operating time per year. (2) MWP is mixed in at 20% only in the winter (to offset coal only). (3) Sub-bituminous A coal. (4) Assumes the ash is considered a solid waste, not special incinerator ash (from the in- cineration of solid waste). (5) Does not include the cost of the fuel silo (which Weyerhaeuser previously pur- chased) or the foundation for the silo (which is already installed) (6) Assumes that no additional air pollution control equipment is required to co-fire MWP fuel. : (7) Ten year level amortization at 10% interest rate. (8) Assumes one additional operations staff is required for MWP fuel handling on each of four shifts. 39 The remaining waste stream is comprised of mixed Paper wastes which is mixed and then goes through a two-stage shredding process before it is cubed. The plant has three parallel cubers which are modified Wamer-Berg pelletizers. Wastech has the ability to vary the density of the cubes, depending on the specifications of the pur- chaser, and is currently producing a cube of approximately one inch cross-section. Test burns of approximately 1,000 tons of pellets were completed in 1985-1986 at the Smurfitt and Scott Paper companies. In addition, a number of pellet samples were analyzed by Weyerhaeuser Labs. Analysis included percent measurements of mois- ture, ash, HHV, chlorine, and sulfur, as well as a spectrographic scan of the ash for a variety of trace metals. Analysis results indicated an HHV range of 6,620 to 8,339 Btu/lb (avg. 7,479 Btu/lb), 2.9 to 14.6 percent for ash content (avg. 8.8%), 8.6 to 23.3 percent moisture (avg. 15.9%), 0.081 to 0.15 percent total chlorine (avg. 0.12%), and 0.02 to 1.2 per- cent (avg. 0.31%) for sulfur. Wastech’s analysis for trace metals revealed acceptable levels of metal concentrations in the pellets. A couple of interesting points mentioned by Wastech regarding potential sources of pellet contamination include paint chips for lead and copper, “Whiteout” as a possible source of zinc, and a fungicide commonly used in the past by paper mills as a possible source for mercury. Wastech, which is headquartered in Oregon, is currently under contract to the City of Portland, Oregon, to collect commercial waste. Wastech is highgrading the commer- cial waste paper it collects and plans to use the lower value MWP as feedstock for its pelletizing process. Wastech has applied for funding from the state of Oregon’s State Energy Loan Program (SELP) to help capitalize a materials recovery facility which would include a pelletizing operation. If constructed, the Portland facility would produce approximately 26,700 tons of MWP pellets per year. Wastech is currently looking for interested buyers of the pellets and has ap- proached the Jefferson Smurfitt Corporation’s pulp and paper plant located in New- berg, Oregon, as a potential user. A test bum of the MWP pellets was completed at the Smurfitt facility during the middle of November 1989. A temporary feed system was installed at the power plant and approximately five tons per hour of MWP pellets were fired over a three day period at the plant’s #10 boiler, a 320,000 lb/hr spreader/stoker unit manufactured by Foster Wheeler. Boiler performance results were favorable as the MWP pellets were getting good bumout on the grates and presented only minor handling problems. ‘Stack emissions monitoring was also conducted during the test period as prescribed by the Oregon Department of Environmental Quality. Emissions monitor- ing included HC1, SO2, NOx, CO, VOC, opacity, and mercury. In addition, heavy metal analysis of the stack gases was completed for the eight criteria metals designated by the EPA. Monitoring results were not available at the time of publication. Provided that regulatory conditions do not constrain the co-firing of MWP, it ap- pears that Smurfitt is interested in using up to 15 percent MWP as a fuel at its New- berg plant. Early discussions between Smurfitt and Wastech indicate that Wastech could provide MWP pellets to Smurfitt at a cost of approximately $15 to $18 per ton, delivered. Wisconsin Case Study In December 1987, a test bum of 54 tons of densified Paper fuel was conducted at the University of Wisconsin-Oshkosh Central Heating Plant. The State of Wisconsin Division of Facilities Management conducted the test to determine if the existing coal- fired boilers could successfully co-fire a densified paper fuel without requiring exten- sive boiler and fuel handing modifications. 40 The Central Plant’s fuel handling system begins with a 250 ton underground fuel storage bunker. Fuel is delivered to the bunker through existing manholes at the bunker top. Hoppers and conveyors located below the bunker transport the fuel to a bucket elevator which conveys the fuel to another hopper located above a coal scale. Once through the scale, the fuel is transported to distribution hoppers where it is then fed directly into the boilers. The boilers are 45,000 lb/hr coal-fired stoker units which utilize a water-cooled vibrating grate system to move the fuel during combustion. During the test, the densified fuel was delivered and emptied into the coal bunkers and fed with the coal to the overhead feeders of Boiler No. 1. The percentage of pellets to coal was varied from 30 to 75 percent, and did not cause any bridging or other han- dling problems outside of a slight increase in fugitive dust due to pellet breakage. Similarly, once initial boiler and stoker adjustments were made, only minor problems were experienced when the boiler co-fired pellets and coal. One of these problems was a slight decrease in boiler efficiency due to increased soot and slag buil- dup on the boiler tubes. This efficiency decrease was largely remedied through in- creased operation of the soot blowers. Another problem experienced with the mixed fuel was an increased potential for fires in both the coal feeder and ash hoppers. Again, it was felt that this problem could be addressed through adjustment of the fuel bed depth and would not require any significant alterations to the existing boiler sys- tem. An additional set of test bums were conducted during March 1988, to evaluate stack emissions and ash toxicity. Emissions tests compared 100 percent coal use to 50 percent coal/50 percent densified paper firing for high and normal boiler loads. The emissions test results indicated that the co-firing of paper pellets would not create any significant emission compliance problems and, in fact, would substantially reduce NOx and SO2 emissions. The results of the test are summarized in Section 3, Environ- mental Considerations. Similarly, the analysis of the mixed fuel ash indicated that it would not be clas- sified as a hazardous waste, and that it could be disposed of in accordance with the regulations governing the disposal of coal. E.P. Toxicity tests for the eight regulated elements are also presented in Section 3, and are shown to be well below the limits for classification as hazardous. The results of the various test burns using the densified paper fuel convinced the state that it could co-fire a 50 percent coal/50 percent pellet fuel mixture at the UW- Oshkosh Central Heating Plant without the need for either new construction or addi- tional operation permits. At a delivered cost of $1.5/MBtu, the densified paper fuel is approximately 25 percent less than their cost for coal and has resulted in an annual fuel savings to the University of $28,000. Citing additional benefits such as reduced acid gas emissions and the diversion of waste material from state landfills, the state has expanded the use of the densified paper fuel to over a dozen state facilities where it is bumed as an altemative fuel to coal. The state of Wisconsin purchases its MWP from General Fuels Corporation (GFC). GFC operates a waste paper densification plant in Neenah, Wisconsin. GFC ob- tains pre-consumer waste paper directly from paper converters located in the state of Wisconsin. The paper they collect includes cardboard, container board, wax coated paper, and other boxboard trimmings which are wasted as part of the production process. The converters pay General Fuels a tipping fee of approximately 50 percent of current landfill costs (tipping fees in Wisconsin are currently tunning from $20 to $40 per ton) to dispose of the waste paper. The collected waste paper is brought back to the GFC fuel processing facility where it is reduced to a 1/2 inch size using a two stage shredding process. The 41 shredded paper is then fed into a modified Califomia Pellet Mill where it is densified. The densification process does not use any binders outside of water and produces a pel- let of approximately 1/2 to 3/4 inches in size. As a result of the waxed paper cuttings, the heating value of the pellets vary with measured values ranging from 8,900 Btu/lb to approximately 10,000 Btu/lb. The densification plant is currently producing between 20 to 40 tons of pellets per day, depending on demand. Their major client is the state of Wisconsin, which is co- firing upwards of a dozen boilers with the densified paper fuel. The state is purchasing the pellets at a delivered cost of $1.50 to $1.75 per MBtu. Additional clients, including a number of small greenhouse operations, are purchasing the pellets at a delivered cost of approximately $2.75 per MBtu, with price dependent on size and location of pur- chase. Although production costs were considered proprietary, GFC admitted that the pelleting operation would probably not be economical without the added value provided by the tipping fee. One producer and two users of densified paper fuel are located in Sioux Center, Iowa. The producer is E-Z Fuels, a division of Van Beek Inc., Biomass Energy and Recycling, which processes corrugate and egg carton flats into a densified fuel pellet. The two consumers of the densified fuel pellet are Dordt College and the Sioux Center Community High School, which together consume approximately 1,852 tons of fuel pellets per year. Van Beek Inc., Biomass Energy and Recycling Van Beek Inc. Biomass Energy and Recycling is a company located in Sioux Cen- ter, lowa, which specializes in the research, development, and utilization of biomass resources. One of the projects which VBI is responsible for is the production of den- sified paper fuel pellets by its division, E-Z Fuel Ltd. The densified fuel is produced using a Lundell pelleting system which makes a 3/4 inch round pellet from 1 to 2 in- ches in length. The pellets produced have an average Btu value of 8,500 Btu/lb, an average moisture content of 8.3 percent, and an average ash content of 2 percent. The current throughput of the system is approximately two tons of pellets per hour. E-Z Fuels is co-owned by local garbage haulers, which recover corrugate and egg carton flats for both resale and as feedstock for the pelleting operation. Currently, the market price received for corrugate is $30 per ton F.O.B, while the pellets sell from $39 to $50 per ton, depending on purchase amount and location. E-Z Fuels also receives a $10/ton subsidy from the City of Sioux Center for handling corrugate was- tes. it College Dordt College is a small, liberal arts college located in Sioux City, Iowa. In 1987, the Iowa Department of Natural Resources awarded the College a 65 percent grant in the amount of $63,150 to install a biomass bumer on an existing natural gas-fired boiler. Designed as a demonstration project, the retrofit enabled the College to bum densified waste paper and corrugate in its number | boiler. The retrofit required the replacement of the boiler’s existing natural gas bumer with a “Sidewinder” bumer manufactured by Northwest Iron Fireman. The new bumer is a Dutch oven type refractory combustion chamber which has a stepped stationary grate with under and overfire air. A variable speed metering system supplies the com- bustor with the densified fuel at a maximum fuel input of approximately 900 pounds of dRDF per hour or 7,650,000 Btu. The densified paper is combusted in the bumer at 2,200°-2,600°F and the hot gases are recovered in the existing Kewanee 200 Hp Scotch Marine boiler which has a rated steaming capacity of 6,900 lb/hr of saturated steam. As the boiler is not equipped with pollution control equipment, the hot flue gas is exhausted to the atmosphere via a 16 foot high stack. 42 Emissions testing of the boiler was conducted as part of the demonstration. Early evaluations measured particulate loading at 0.6 lbs/MBtu which just met the Iowa State emission standard of 0.6 Ibs/MBtus of heat input. Although the College was in compliance and has continued to operate the boiler, they are currently in the process of installing a two-stage cyclone for particulate control. Additional testing of the flue gas stream is underway and should be released by early 1990. Among other parameters, priority pollutants, including chlorine, are being measured. The College has operated the boiler for over two years and has been very satisfied with its perfonnance. Currently, the converted boiler is carrying 90 percent of the College’s steam load and has displaced the use of 23,877 kCF/yr of natural gas. Ata purchase price of $3.30 per kCF ($.33/therm), this amount of gas would have cost the College $78,795. Instead, the College is purchasing approximately 1,490 tons per year of the densified paper fuel from E-Z Fuels Ltd. At a delivered cost of $40 per ton, or $59,620 per year, the College is saving more than $19,000 per year in fuel costs. ‘ent igh Sc! In July 1987, the Sioux Center Community High School also retrofitted their exist- ing natural gas boiler with a “Sidewinder” bumer to enable them to bum densified paper fuel. The school’s existing boiler was a Kewanee 125 HP, 3-pass firebox boiler which had a rated output of 4.25 MBtu/hr. As with the Dordt College retrofit, the high school has been satisfied with the operation of the converted boiler. The boiler carries 100 percent of the school’s steam load and consumes 362 tons/yr of the fuel pellets. At a $40 per ton purchase price for the pellets, Sioux Center Community High School is saving close to $9,300 in fuel costs, annually. Summary In 1987, Washington State citizens generated approximately 460,000 tons of MWP, of which only 34,000 tons were recycled. By the year 2010, projections indi- cate that more than 961,000 tons of MWP will be generated in the state, of which 215,600 tons are forecast to be recovered. : While forecasters feel confident in their projections of MWP generation levels, they are less so in their projections of future recovery rates of MWP and admit that it will depend on how current regulatory and market conditions evolve. Currently, there is a secondary fiber market for MWP. This market is largely dependent on overseas sales, however, and has begun to show signs of weakness. As of early 1989, brokers of MWP in Washington State were getting about $15 per ton for baled MWP in inter- modal containers FAS (free along ship) at the Port of Seattle. This price was down from earlier rates and is expected to drop even further as reflected in recent bids of ap- proximately $3 to $5 per ton. . The use of MWP as a fuel appears promising and could represent an alternative market provided that it’s use satisfies federal and state regulatory conditions and could be purchased at a competitive price. Using the existing collection system, MWP could be transported to a central processing facility where shredded and pelletized MWP fuel could be produced. Processing costs are estimated at $10 per ton for shredded MWP and $30 per ton for pelletized MWP. Transportation/handling costs would add another $5 per ton or more to the cost of production, increasing the base price for MWP fuel to $15 and $35, respectively. The economics of using MWP fuel are shown to be specific to the end-user facility and will depend on a given facility’s operating and maintenance costs, retrofit costs, and competing fuel costs. Site-specific analysis of three representative facilities sup- 43 port this, as break-even costs to these potential users ranged from $5 to $19 per ton. These prices are significantly lower than the cost to produce MWP fuel and would not provide sufficient incentive to a MWP processor given current market conditions. This situation could change, however, if a collector of MWP is faced with a disposal cost or tipping fee which would offset the cost of production. A changing regulatory environment will also influence the value of MWP as a fuel. Analysis of MWP completed for this study suggests that MWP fuel is com- parable to both coal and hog fuel with respect to environmental characteristics and should not create any significant environmental compliance problems. The fact that MWP is diverted from the solid waste stream might present problems, however, as solid waste materials are strictly regulated under both state and federal laws. Under proposed amendments to the Clean Air Act, the U.S. Environmental Protection Agen- cy appears to have defined MWP as a solid waste. If this occurs, facilities using MWP fuel could be subject to proposed emissions standards for new incinerators which would adversely impact the economics of MWP use due to increased capital, operat- ing, and administrative costs. . Acknowledgements This work was funded by the Washington State Legislature. The assistance of the Washington State Energy Office support staff in producing this paper is sincerely ap- preciated. R.W. Beck and Associates provided information for the retrofit portion of this paper. 44 References, Cited . Ainsworth, C.C., and Rai, D., Chemical Characterizations of Fossil Fuel Combus- tion Wastes, Palo Alto, CA; Electric Power Research Institute, EA-5321, Septem- ber, 1987. . American Paper Institute, 1988 Annual Statistical Summary Waste Paper Utiliza- tion, Third Edition, New York; American Paper Institute, June, 1989. . Environmental Protection Agency, The Solid Waste Dilemma; An Agenda for Ac- tion; Appendices A-B-C, Washington; Environmental Protection Agency, EPA/530-SW-88-054B, September, 1988. . Franklin, W.E., Franklin, M.A., and Hunt, R.G., Waste Paper the Future of a Resource 1980-2000, Prairie Village; Franklin Associates, Ltd., December, 1982. . Gildart, M. and Pasek, R., Coordinated Waste, Ash, and Emissions Sampling, at the Commerce Waste-to-Energy Facility, Proceedings Intemational Conference on Municipal Waste Combustion, Volume 1, pp. 5C-31 - SC - 49, Hollywood, Florida, April 11-14, 1989. . Law, S.L., and Gordon, G.E., Sources of Metals in Municipal Incinerator Emissions, Environmental Science and Technology 13, 432-438, 1979. . Matrix Management Group, R.W. Beck and Associates, and Gilmore Research Group, Best Management Practices Analysis for Solid Waste Volume 1, 1987, Recycling and Waste Stream Study, Olympia; Department of Ecology, December, 1988. . Norton, G.A., Malaby, K.L., and DeKalb, E.L., Chemical Characteristics of Ash Produced During Combustion of Refuse-Derived Fuel with Coal, Environmental Science and Technology, 22, 279-283, 1988 . Perkins, K. and Dohms, P., Using Wood Ash for Landfill Cover, Solid Waste and Power, 3: 32-39, August, 1989. 10. Washington Department of Ecology. Draft: Use of Recycled Paper in Existing Washington State Paper Mills, Olympia: Department of Ecology, 1989. 11. Washington Department of Ecology, Olympia, Private Communications, December 13, 1989. 12. Watson, E.B., Incineration of Municipal Solid Waste Toxicity of Ash Residue, State Government Technical Brief, 1987. Washington American Society of Mechanical Engineers. 13. Wisconsin Department of Administration, Utilization of and Evaluation of Refuse- Derived Fuel at UW-Oshkosh, Project Report No. 8803-19, August, 1988. 45