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Chevak Waste Heat Recapture Project Preliminary 4-19-91
PROJECT:CHEVAK WASTE HEATRECAPTUREPROJECT <0State of Alaska Alaska Energy Authority P.O.Box 190869 701 East Tudor Road Anchorage,Alaska 99519-0869 PRELIMINARY =:/19/91 ----47 Chevak Waste Heat RecoveryReportandConceptDesign Executive Summary Chevak is a rural community located in Western Alaska on the banks of theNinglikfakRiver,approximately 115 miles northwest of Bethel.The population ofChevakisapproximately594.This study was performed by Alaska Energy Authority(AEA)staff to determine the feasibility of constructing a waste heat recovery systeminthecommunity.The heat recovery system would recover thermal energy from theAlaskaVillageElectricalCooperative(AVEC)power plant that is rejected to theatmospherethroughradiatorsandusetheenergytoheattheSchoolDistrictfacilities.With the present cost of heating oil at $1.06 per gallon and an averageannualfuelconsumptionof57,317 gallons,the annual cost of heating fuel for the -school facilities is approximately $60,000. A heat recovery system is a relatively simple system.Typical baseboard-heatedbuildingshaveaboilerwhichtransfersheattowaterandapumptocirculatethewaterthroughthebaseboardradiators.The baseboard radiators heat the building.A heat recovery system works in the same manner,with the exception that thegeneratorengineratherthantheboilerprovidestheheat.Because the engineprovideswaste-heat that would otherwise be rejected to the atmosphere,less fuel isrequiredforheating.This report discusses how waste-heat may be used in Chevak,and the expected results. The Kashunamiut School District school facility was determined to be the most like!candidate to receive waste heat in Chevak.is facility is adjacent to the AVEC_power plant and could utilize 100%of the heat available from the power plant duringthewintermonths. Project cost,annual amount of fuel saved and fuel cost savings are as follows: Project Cost $186,253 Amount of Fuel Saved per Year 24,203 Annual Savings $25,655 Straight Pay Back in Years 73 Total project cost includes design,supervision,inspection,administration andconstruction.The project includes the construction of a platform at the power planttosupportastructurethatwillhousethewasteheatrecoveryequipment,modifications to the AVEC power plant cooling systems,installation of the arcticpipingfromthepowerplanttotheschoolbuilding,and tieing into the existingschool-complex heating system at the school building. The practical useful-life of a waste heat recovery system is related to the availabilityofwasteheatfromthepowerplant,the need for heat at user buildings,and systemmaintenance.The long-term outlook for the availability of waste heat from the Chevak Waste Heat RecoveryReportandConceptDesign AVEC power plant and the need for heat by the school is good.With propermaintenancethelifeofthewasteheatrecoverysystemwillexceed25years. The average annual maintenance cost to repair failures in the waste heat recoverysystemisestimatedat$1,150/year.Routine maintenance will be performed twice ayearbyaskilledcrewatanestimatedcostof$5,000/year.The total estimatedaverageannualcostformaintenanceis$6,150/year.Daily operation of the systemwillbeperformedbyschooldistrictmaintenancepersonnel. Because annual operational and maintenance costs and economic decisions will bemadeatalaterdate,final economic conclusions are not presented in this report.The straight pay-back time for the project based on an estimated cost of $186,253andannualsavingsof$25,655 is 7.3 years. Chevak Waste Heat RecoveryReportandConceptDesign CONTENTS Executive Summary .......sccscssssseccscsssscesssesssssssssssescssesssssssesessssssossssssoesssnessessessesessecasssssssesss i List Of Figures ........ccssssscssssssecssecsessssscessssssssesssesosssesesesesseserssesesecorscesessessseessesssnsesescesscoessesees Vv List Of Tables ...........sssssssscsscsssssssssrssscesssseesssensessssesesesscsesesscversscesssssensecersssasseessasesssssesesesescess vi I.Introduction A.Objective sensesecssssececossscesesssscosososaseessssseeasenssasasesscesssesorsssssecesessecsssoeseeeseees 1 B.Methodology .........sssssssssssserssecssccsssssssssnenssssccesesesesssscserssenscssesesssessncesecsseseseesscessees 1 C.Community Description .........sesseceeasasecesseseeeteces 2 D.Projected Load Changes ..........sssscscssscsssssssscssceesssesesssesssncsesssnserersssseasseseesenscstecss 2 IL.Site Visit sesssecessceseeenee .sssesscsseccscesssssecssscsseseescacessesssessseessesssecesesereasers 3 Ill.Power Plant 7Nn 1 1)6.)ne a 4 B.Available Load Information &Available Heat ............cssssssssssssesessesssssseserees 6 C.Building Heat oc sssssessssssssessscesseseesssesssessssesscsssessscsssseessssnsesssssaseenesssecseecesees 7 D.Proposed Waste Heat Connection .......s.cessscssssssssssssssssessesscecersssessesssssesennsssetecs Y IV.Potential Waste Heat Users A.School Complex 1.General sesseseeataces sesscesessscssesssecesscssessesssesesssssessseescessserereseeee®1] 2.LOCALION .....cssssssoeceseccscesessscssssscsessessensersssssarensssscassesssasssenserssessrsesensseeseusesses 11 3.Fuel Consumption ........cccsseeeees sessasesessseceeeeeeess 11 4.Pipe Routing and Waste Heat Connection ........csssssssssessssssssesesseseseeessees 12 B.Day SCHOO ....csssssscsssssssssccsssesssssessssssssesesesesesssssssseasasonsesnsesesecnsesssseessessesseaeatanstees lo OFS)0 (0)»Eeeee 16 D.Duplex ...ssvsessscacssecssssenossacssscescosssscscserssnsacecssonseesenececsesecssveseeseseeseseeses 16 E.Five-Plex .sesteensususceecenscssesssasseosascosscasensoscssensesessscaseasesasesseesesasansesese®16 F.Art Building...scsscssscsssscssssccssssssscesscssesssssssssssssnrsssssssssessesessesesessasssceaeseeseneersees 17 Chevak Waste Heat RecoveryReportandConceptDesign G.Boiler Plant .........sssscsssssssssescsssccsesssesssnesessssssessossssssossesesnsssssesessessassecesnssecnesesseees 17 V.Concept Design Drawings ......s.ssssssssssscsssscssssssssesecnsessesesescssesecessesesesecesseseseserstsecessces 19 VI.Failure Analysis A,IntrOductiOn .......csscccssscsssscssesssscsscesecssssecssessssosesesessensnsusccescacesensesssssesesesesssesoseasers 24 B.Failure Modes and Impact..........csssscssssssssssssscesssssseseresessssesscesesessssesssessesssseseses 24 1.Gereration System ..........sssssssscssscscssccsssssseseseesscessesesssnssenacoressssssasesssseesoees 24 2.Distribution System and User Connection...scsscsseessesssssseesssesssseesess 26 C.Failure Frequency and Cost ..........ssssssssssssssssssesssssssssccessssssesssssecessenensacssssessereces 28 D.Design Decisions to Minimize Failures ..........ssssssssssssssssssssesessesssssssnseenssesseees 28 VII.Project Specifications A.Codes and Regulations ..........ssssssssssssscerssessssseressssesesesessssssenscasesessesssesssesssereeees 30 B.DIVISION 01 -General Requirements | seseaseeeenseseeeees 30 C.DIVISION 02 -Sitework .0.......sesssesssesssscsssosesscnsessesosecosscssssssssessnceseseessneesesesessees 30 D.DIVISION 13 -Special Construction ........cssssssssssesssssssesssssessssssesesesssnsssesssseeees 30 E.DIVISION 15 -Mechanical Outline Specification 0.0.0...sssesssssseesseseeeeeees 31 F.DIVISION 16 -Electrical Outline Specification 0.0....essssssssseseesseesereestereeees 33 VIII.Project Cost Estimate A.Power Plant Heat Recovery System ........ssssssssccssseesssssssssssscseesssseseseressseeneteesees 35 B.Waste Heat Distribution System 0.0...cssssssesscssesssesssececssesessesesscesesesessssesseces 35 C.Operation and Maintenance Costs ........sssssssssccscssssssssesscssnseeseessesseessesesearerees 35 D.Project Cost SUMMALY .........cccsessssssssccscsesesessesssssecccecoesssseressecssscnsssneseseseeseseteeets 36 IX.Conclusions A.Heat Availability &Fuel Consumption «0.0.00...ssscssssssesssssssesssereresesesesesrssseeses 37 B.Project Cost SUMMALY ........cscsssessssessssssseessessssesssessssessssesessesessesssessosnsessesesseseess 38 C.Project Summary sesesesssvsossssssosssnsssssssoessscsssssosesesscesesssssosssesacesesasessseesossssesess 38 X.REcOMMENAALtiOnS .........scccccccsssnscsscssevsssese sesccccccescsescsacscescessonscscscorscssesonscensecscnsescces 39 Chevak Waste Heat RecoveryReportandConceptDesign Calculations ...........cssscssssssssssscesssssscsesssecssscsscsssseseeeeeeees Appendix A Field Trip Notes wees .Appendix B Cost Estimate ........cssssssssccsssssssssssssssesssssssesesssssossssscssesesosecsssssececesesesesescesssares Appendix C List of Figures IIJ-1 Butler Building Unit Heater and Position #1 Heat Exchanger .............csssecsrsceees 8 TI-2 Hussman Module Heat Exchanger and Coolant Piping ............sssscssssssssseserseeseees 8 III-3 Butler Building Proposed Waste Heat Module Location ou...esssecessecsssseeeees 10 III-4 Proposed CCoolant Piping Alignment form Hussman Module to Butler Building..7 IV-1 Proposed Waste Heat Piping Alignment to Day School 0.0...cessssssssssssesereesees 14 IV-2 Proposed Waste Heat Piping Alignment in Day School Crawl Space ............14 IV-3 Proposed Connection to Existing Piping in Fan ROOM #3...esssssseeseeeeeees 15 TV-4 Chevak Day School 0...ssssssscscssssscssssesscssssnssssssesessseessessssscssacasessssssacasesesesesseseses 18 IV-5 Boiler Plant Heating System .......-.sssssssssessssssscecsesssnnssseecenensnnnsseeceeeceesennneseesee 18 V-1 Site Plan &Proposed Waste Heat System Distribution ............escsssceeseeeseeeees 19 V-2 Proposed System Schematic .......sccsssscssssovssssssecsssssssserscsessssesscssseessetscesecsssesesecees 20 V-3 Proposed Hussman Module Piping Schematic and Floor Plan ou...eee 21 V-4 Proposed Butler Building and Waste Heat Module Piping Schematic and &FIOOr Plan .....sesssssssssscssesesssesesereceeeneeees ssoscsssestscssesessssssssecessssssessess 2 V-5 Proposed Fan Room #3 Waste Heat Connection Piping Schematic and FloorPAM....sscccccscsesscscnesecossessseseeesereseseseeeess seatecesaseeasesesesesscscenseenes 23 IX-1 Heat Demand vs.Heat Displaced .............sssssecsssccscessssesssensecessscesscsesscsssessarereeses 37 Chevak Waste Heat RecoveryReportandConceptDesign List of Tables III-A Engine Data sssssssessecscosecasessecacccacensesssceseeesoresessseacasesessseasasscssesceseeesenses 5 III-B Monthly Power Generation &Available Heat ..........ccsssssssessessscssssessesesssesees 6 IV-A Estimated Fuel Use per Building for Heat and Hot Water ........csesssssseeseees 12 VITI-A Summary of Project Costs ......ssscsssssssssssosesssssesssesessssssessnscsssssesesssassossesessseosseesess 36 IX-A Annual Heating Fuel Displacement &Pipeline Heat Losses ..........tesco 37 IX-B_Project SUMMALY .......sssccecsseeseseseseeseees stasasesaseessssssssasacsons 38 v1 Chevak Waste Heat RecoveryReportandConceptDesign I.Introduction A.Objective The objective of this study is to determine the viability of recovering wasteheatfromtheAlaskaVillageElectricCoop.(AVEC)diesel electricgeneratorsinChevakforheatingthenearbyschoolcomplex.The powerplantcurrentlyrejectsvirtuallyalloftheheatproducedbytheenginestotheatmospherethroughradiators.With the school complex consumingapproximately57,000 gallons of heating oil per year at a current cost of $1.06pergallon,there is the potential for significant savings.Members of theschooldistrictareveryenthusiasticaboutthepotentialofthisproject. B.Methodolo The following approach was used in the development of this study: 1.Information Gathering:Prior to the site visit information was gatheredregardingtheAVECpowerplant,the school facilities,and thecommunityingeneral.A preliminary run of the Waste Heat Utilizationcomputermodelwasperformedusinghistoricalpowerproduction,weather information,estimated fuel usage records,and utility generationsystemparameterstodeterminethequantityofwasteheatavailable.Theresultofthisrunindicatedthattheschoolcouldconsume100%of the waste heat available. Due to this fact,and the close proximity of the school to the power plant(37 feet),it was concluded that the school would be the only facilityinvestigated.The field trip was coordinated with the Kashunamiut SchoolDistrictSuperintendent,Al Weinberg. 2.Field Investigation:The site visit was made to discuss the project withmembersoftheschooldistrictandcollectdataontheschoolheatingsystemandthepowerplant.As-built information was obtained for thepowerplantandtheschoolbuildingsinsufficientdetailtoallowpreparationoftheconcept-level design,including required modificationstotheAVECpowerplantandaproposedpipingroute. 3.Analysis and Report Preparation:Field notes,photographs,generalinformationandadditionalsite-specific features of the school wereanalyzed.Drawings depicting the proposed design were prepared.AfinalrunoftheWasteHeatUtilizationcomputermodelwasperformedusingdatacollectedduringthesiteinvestigationtodeterminethetotalquantityofwasteheatavailableforuseattheschool. Chevak Waste Heat RecoveryReportandConceptDesign C.Community Description Chevak is located in Western Alaska on the banks of the Ninglikfak river,115milesnorthwestofBethel.Information from the FY 1990 State Revenue Sharing Program lists the population of Chevak at 594.The community isonlyaccessiblebyairandriver,with daily commuter service from Bethel. The local economy is based primarily on fishing and subsistence.OthereconomicactivitiesincludeoperationsoftheCityGovernment,theKashunamiutSchoolDistrict,the local Native village corporation,the ChevakCompany,and sales of native handicrafts both within and outside thecommunity. There is minimal construction equipment available locally and some skilledlabor.The summer construction season generally runs from June throughSeptember.The School District is interested in the possibility of participatinginthefinancingandconstructionofawasteheatproject. D.Projected Load Changes The school district has requested funding from the state to add an additional3,000 square foot addition to the main school building.Since the presentschoolthermalloadexceedstheutilitythermaloutput,it is not necessary tosizethewasteheatsystemforfutureincreaseddemand. Mark Teitzel,Engineering Manager of AVEC stated that the peak load atChevakwas320kW.This is the rated capacity of the existing 3412 CaterpillarintheHussmanmodule.Although AVEC has not included plans forincreasedgenerationcapacityinChevakinitscurrenttwoyearplan,Mr.Teitzel believes that increased capacity could be required as early as 1993 or1994.(AVEC's current approach is to replace a 3412 Caterpillar with aCumminsKTA38,1200 RPM unit.)Therefore,the waste heat primarycoolingsystemshouldbesizedadequatelyforbotha3412andaKTA38. Chevak Waste Heat RecoveryReportandConceptDesign II.Site Visit "Se ::"e 27 A.Description resoanphate!Tee Steven Stassel of the Alaska Energy Authori visited the site from January 17through19,1991.Meetings were conducted with the schoolsuperintendent,the school 'principal,the school maintenance staff,and AVEC.power plantpersonnel.Information was obtained regarding land ownership and right-of-way,soils and climate,operation and maintenance of heating and generationsystems,power production and fuel use,availability of local labor andconstructionequipment,and community desires. B.Field Contacts . ee Al Weinberg School Superintendent --858-7714 Henry Versnick Principal .4 858-7713 Albert Ulroan High School Maintenance'a 858-7713 Frank Smart AVEC Plant Operator -==_858-7212 Henry Smart Assist.AVEC Plant Operator -858-7615 ioe1wel Chevak Waste Heat RecoveryReportandConceptDesign Ill.Power Plant A.General The AVEC power plant consists of both a Butler building and a Hussmanmodule.The Butler building contains two Caterpillar generators which areequippedwithskidmountedradiators.The building also contains the switchear,day tank,hydronic heating system,and a storage and work area.TheussmanmoduleisadjacenttotheButlerbuildingandcontainsoneCaterpillargeneratorwitharemoteradiatorandahydronicheatingsystem(see Table III-A for Generator Data). Position #4 (Hussman module)is the lead generator and is run mostfrequently.Position #1 is run during maintenance on position #4.Position#2 is run during the summer and in emergencies.Position #3 is currentlyvacantbuttheunitinposition#4 may be relocated here if a larger unit isinstalledinplaceoftheHussmanmoduleinthefuture. The units in positions #1 and #2 are each equipped with skid mountedradiatorsthatdrawairfromwithintheButlerbuildinganddischargedirectlyoutsidethroughback-draft dampers.The unit in position #4 is equipped witharemoteradiatorlocatedintheroom(plenum)adjacent to the generator intheHussmanmoduleanddrawsairfromoutsidethroughasnow-hood anddischargestotheoutsidethroughasnow-hood. Arctic Diesel Number 1 fuel is purchased annually from Pacific Alaska Fuelandstoredineighteenfueltanks(approximately 137,500 gallons totalcapacity)adjacent to the power plant.The fuel is then transferred by pumptoa285gallondaytanklocatedinsidetheButlerbuilding. Chevak Waste Heat RecoveryReportandConceptDesign Table III-A Engine Data (@ Prime Rating w/o Fan) Position #an ae .@ ¥4 Model D353 «342.=Vacant =3412 Speed (RPM)1,200 1,200 N/A-1,200 Rating (KW)300 160 NIA =,330 Water Flow (GPM)140 5 NIA 118 @ Head (FT)30(max) 15(max)N/A _10 (max) Intake Air(CFM)1000 625 N/A =1020, Heat Rejection ge ee(BTU/MIN),a eer ToCoolant -15,600 *..9,400 NIA 13,281 ToStack N/A N/A N/A 18,420 To Ambient 3,900 2,894 N/A 4,459 7totheow Chevak Waste Heat RecoveryReportandConceptDesign B.Available Load Information &Available Heat Monthly power production and fuel consumption data for FY 90 wereobtainedfromPCEdatasubmittedfromAVECtotheAlaskaEnergyAuthority.The amount of waste heat available off the engines was calculatedusingthereportedgenerationvaluesandtheenginemanufacturer's heatrejectionfigureslistedinTableIII-A.System losses were subtracted from theamountofheatavailableofftheenginestoarriveatthenetheatavailable. System losses include distribution pipeline heat losses,radiator losses,andplantheatingandpipinglosses.The waste heat equivalent in gallons of fueloilwasthencalculatedusingthenetheatavailableandassumingaboilerefficiencyof73%as shown in Table II-B. Table II-B Monthly Power Generation,Fuel Consumption,&Available Heat Month Power Fuel Ratio Heat Produced Used Avail (KWH)(GAL)(KWH/GAL)(GAL FUEL) Jan 119,080 9,627 12.36 2,582 Feb 105,720 9,036 11.69 2,305 Mar 106,440 9,327 11.41 2,381 Apr 86,680 8,245 10.51 2,065 May 86,400 7,407 11.66 2,132 Jun 67,440 6,348 10.62 1,832 Jul 75,280 7,741 9.72 2,025 Aug 90,320 8,209 11.00 2,252 Sep 89,400 7,747 11.54 2,178 ,Oct 107,600 8,945 12.03 2,522 Nov 111,120 -1,545*N/A 2,483 Dec 116,720 9,577 12.19 2,534 Total 1,162,200 90,664 12.82 27,291 *A negative fuel quantity reflects a fuel adjustment Chevak Waste Heat RecoveryReportandConceptDesign C.Building Heat The Butler building is a metal frame building approximately 36 feet long and14feetwidewith2inchinsulationinthewallsandroof.The building has anuninsulatedwoodfloorcoveredwithsteelplate.Intake air is providedthroughventilationdampersbythedoor.Both units in position #1 and #2haveskidmountedradiatorseachequippedwithaback-draft exhaust airdamper.A shell and tube heat exchanger is used to capture heat fromiy.1 and provide heat to two ceiling mounted unit heaters (See FigureIII-1). The Hussman module is 24 feet long and 10 feet wide.The generator islocatedinasectionofthemoduleapproximately17.5 feet long and the widthofthemodule.At the end of the module is the radiator plenum.This room is6feetlongandtenfeetwideandcontainsaverticalradiatorandassociatedpiping,an amot valve,a shell and tube heat exchanger for the hydronicsystem,and fresh-air and exhaust-air dampers (See Figure III-2).Thehydronicsystemprovidesheattooneceilingmountedunitheaterinthemodule.Two 3/4 inch copper supply and return lines run between the ButlerbuildingandtheHussmanmoduleandconnectthehydronicsystemsineach building. Chevak Waste Heat RecoveryReportandConceptDesign Figure HI-1 Butler Building Unit HeaterandPosition#1 Heat Exchanger Figure III-2 Hussman Module Heat Exchanger and Coolant Piping 91Q2\IT0581(2)x Chevak Waste Heat RecoveryReportandConceptDesign D.Proposed Waste Heat Connection and the connection to the power plant is shown in Figures V-3 and V-4 (pages21&22).The primary heat exchanger,radiator for positions-1-and 2,andassociatedequipmentwillbecontainedinahousingmadeofstandard2x4woodframeconstruction.The housing will be mounted on a steel channelPlatformconstructedonthesideoftheButlerbuilding(See Figure III-3 forocation).The platform will be attached to the floor joists of the building andwillprovideadequatespacefortheheatexchanger,radiator,and associatedpiping.The unit will be insulated with fiberglass batt insulation arid will haveametalsidedexteriorwithsheetrockinterior.Intake and exhaust hoods fortheradiatorventilationwillbeprovided.Sofa T Ft OS®+ct The proposed waste heat system schematic is shown in Figure V-2 a 20) Modifications to the existing primary cooling piping in the Hussman modulewillincludereplacingallexisting2-1/2"primary cooling piping with 4"schedule 40 welded black pipe and installing a line-size Amot valve.4"supplyandreturnlineswillbeattachedtothesideoftheHussmanmoduleandtie into the primary heat exchanger (See Figure III-4 for location).All piping willincludeflangesforvalvesandotherremovablefittings.ai The radiators on Positions #1 and #2 in the Butler building will be removedalongwiththefanandpulleyassemblies.Both Positions will be piped inparalleltoanewradiatorviaa4"supply and return manifold..The supplymanifoldwillbepipedthroughtheheatexchangertoaline-size amot valveinstalledinamixingarrangement.4"welded schedule 40 black piping withflangesforvalvesandotherremovablefittingswillbeused.Valves with blind flanges will be provided at position #3 for future use. The Amot valves will have a factory-set thermostat that will regulate thereturncoolanttemperaturetotheenginestopreventoverheating.-When thecoolanttemperatureleavingtheheatexchangerexceeds180degrees,thevalvewillmodulateopenandallowcoolanttopassthroughtheradiators. A three-chambered plate and frame heat exchanger-wilf®e used with onerimarychamberconnectedtoPositions#1 and #2.in the Butler building.The second primary chamber:will be connected-to -Position "#4 in theHussmanmodule.The third (secondary)chamber will provide the waste heatfromthepowerplanttotheschool.e waste heat expansion tank andcirculatingpumpswillbelocatedinFanRoom#3..-ee The Butler building and Hussman module hydronic systems will remainindependentoftheproposedwasteheatsystem._- The cost estimate for the construction of the project,including the connectionoftheheatexchangerandassociatedequipmentandmodificationstotheexistingcoolingsystem,is covered in Section VIII,Project Cost Estimate. EScscoaaee Chevak Waste Heat RecoveryReportandConceptDesign =eenapresi>®: ; Ak.c.* Figure III-4 Proposed Coolant Piping Alignment fromHussmanModuletoButlerBuilding 91 Q2\IT0581(3) Chevak Waste Heat RecoveryReportandConceptDesign IV.Potential Waste Heat Users A.School Complex 1.General Description The Kashunamiut School District has an enrollment of 185 students from kindergarten through grade twelve.The school complex consistsofsixbuildingstotalingapproximately42,000 square feet.These aretheDaySchool,Shop,Duplex,Fiveplex,Art building,the Boiler plant.There are also several trailers used for classes.Each of the buildingsreceivesbothheatanddomestichotwaterfromtheboilerplantandareheatedbyacombinationofforced-air and baseboard hydronicsystems.The trailers each have their own independent oil firedheatingsystems. 2.Location As is shown in Figure IV-1,the school complex is located 37 feet westoftheAVECpowerplant.The piping run Is approximately 300 feetonewayfromtheButlerbuildingtothewasteheattie-in in Fan Room #3. 3.Fuel Consumption Fuel delivery records for the school complex were obtained from theschooldistrictfor1988,1989 and 1990.Consumption data is not available for individual buildings but was estimated from quantities offueldeliveredeachyear.The average annual fuel delivered the pastthreeyearswas57,317 gallons.It is assumed that this is the averagequantityoffuelconsumedperyear.5,317 gallons of fuel wassubtractedtoaccountforthefuelconsumedforheatingandprovidinghotwatertothetrailersthatarenotconnectedtotheboilerplant.Distribution of the remaining 52,000 gallons between the buildings thatreceiveheatandhotwaterfromtheboilerplantwasestimatedbasedongrossbuildingarea.As shown in Table 1V-A,monthly fuel use perbuildingwasdeterminedbydistributingtheestimatedannualgallonsconsumedperbuilding,based on the number of heating degree dayspermonth.10%of the total fuel consumed was assumed to be usedfordomestichotwater. Chevak Waste Heat RecoveryReportandConceptDesign Table IV-A Estimated Fuel Use per Building for Heat and Hot Water Month Deg School 5-plex Duplex ArtBldg Shop Plant Days__(Gal)__(Gal)__(Gal)(Gal)_(Gal)(Gal) Jan 1804 =5,018 864 380 388 357 =326 Feb 1565 4,391 756 333 340 313.285 March 1659 4,638 799 351 359 330 =301 April 1146 3,293 568 250 255 235 «214 May TIS .2,321 402 177 180 166 =151 June 372 0 221 97 99 91 83 July 326 0 200 88 90 83 75 August 381 1,288 225 99 101 93 85 Sept 591 =1,839 319 140 143 132120 Oct 1029s 2,987 516 227 232 213-194 Nov 1440 384,042 700 308 315 290 264 Dec 1792 4,986 858 377 386 3553.23 Annual 12880 34,824 6,428 2,826 2,888 2,658 2,422 4.Pipe Routing and Waste Heat Connection Two 2-1/2""Arctic"distribution pipes,one for supply and one forreturn,will be used for distributing the waste heat from the powerplanttothecentralheatingloop.The pipes will be routed beneath theButlerbuildingalongthefloorjoistsandextend37feetbelowgradetotheeastsideoftheschool.The pipe will enter the crawl space of thebuildingandbesuspendedbeneaththeschoolfloor,attached to thefloorjoists(See Figure IV-2).The connection to the existing schoolcomplexheatingloopwillbemadeatFanRoom#3. Chevak Waste Heat RecoveryReportandConceptDesign Approximately 300 feet of piping will be required one-way from thepowerplanttoFanRoom#3 in the main school building.The mainschoolheatingsystemwasrenovatedin1987/88 and the system wasdesignedtoaccommodatewasteheat.This included sizing the heatingcoilsandbaseboardradiationfor160degreesupplywater.In addition,the main school was connected to the boiler plant via 4"copperheatingsupplyandreturnlinesthatrunthroughtheexistingutiliduct.As shown in Figure IV-3,4"piping stubs are providedinFan Room #3forconnectionofthewasteheatpipingtatheboilerreturnline. The waste heat circulating pumps and expansion tank will be idcated inFanRoom#3.The supply and return piping will be tied directly intotheschoolreturnpiping.A two-position three way valve will be usedtocontrolthewasteheatsupplytemperature.Under normal .*conditions,the valve will allow flow from the school return piping totheheatexchanger.Should the waste heat supply temperature dropbelowthetemperatureofthereturncomingfromtheschool,the valvewillswitchandbypasstheschoolsystem.The waste heat fluid will becirculatedbacktotheheatexchangerandallowedtoreheatuntilthe supply temperature exceeds the school return temperature. A low pressure shut-off switch will be incorporated in the waste heatsupplylineatFanRoom#3.In case of a severe leak in the waste heatpipingandlossofpressure,the circulating pumps will shut off and thethree-way valve will switch so that the school heating system will bypassthewasteheatloop.A check valve in the waste heat supply line willpreventbackflowfromtheschoolheatingsystemintothewasteheatpiping.In this way,the school heating system will be protected in caseofafailureinthewasteheatpiping. After the cause of the low pressuge has been corrected,the loop can bere-charged by adding glycol at thé expansion tank in Fan Room #3.The circulating pump will start amt the waste heat loop will circulatethroughtheheatexchanger.Once the waste heat supply temperatureexceedstheschoolreturntemperaturethethree-way valve will openandallowflowfromthewasteheatlooptotheschoolheatingsystem. Easements should not be required since the piping will be entirely onschooldistrictandAVECutilityproperty.as Chevak Waste Heat RecoveryReportandConceptDesign :"att vsSemeleSWe Ok ee Figure IV-2 Proposed Waste Heat Piping Alignment in Day School Crawl Space 91Q2\IT0581(4)14 Chevak Waste Heat RecoveryReportandConceptDesign Figure IV-3 Proposed Connection to Existing Piping in Fan Room #3 91Q2\IT0581(5)is Chevak Waste Heat RecoveryReportandConceptDesign B.Day School 1.General The Chevak Day School is a wood frame structure on pilings consistingofasingle-story classroom area,a gymnasium,multi-purpose room,and two second story mechanical rooms (See Figure IV-4).Theoriginalbuildingwasconstructedin1976andanadditionaddedin1983.Total building area is approximately 28,000 square feet.Thebuildingisingoodconditionandappearstobewellmaintained. 2.Heating System The building is heated with hot water baseboard radiation and forcedairventilation.All heat is provided by the central boiler plant.Domestic hot water is provided by a large hot water generator locatedintheboilerplant.The waste heat tie-in will be in Fan Room #3 (seepage12,Pipe Routing). C.Shop 1.General The shop is a single story wood frame building on pilings and is in faircondition.Total building area is approximately 2,140 square feet. 2.Heating System The heating system consists of ceiling mounted unit heaters that receive heat from the central boiler plant. D.Duplex 1.General The Duplex is a wood frame structure on pilings.Total building area isapproximately2,275 square feet. 2.Heating System The building is heated with hot water baseboard radiation.Domestichotwaterandbuildingheatareprovidedbytheboilerplant. E.Five Plex 1.General The Five-plex is a wood frame structure on pilings.Total building areaisapproximately5,175 square feet. lo Chevak Waste Heat RecoveryReportandConceptDesign 2.Heating System The building is heated with hot water baseboard radiation.Domestichotwaterandbuildingheatareprovidedbytheboilerplant. F.Art Building 1.General The Art building is a wood frame structure on pilings.Total buildingareaisapproximately2,325 square feet. 2.Heating System The building is heated with hot water baseboard radiation.Domestichotwaterandbuildingheatareprovidedbytheboilerplant. G.Boiler Plant 1.General The Boiler Plant is a wood frame structure on pilings.Total buildingareaisapproximately1,950 square feet. 2.Heating System As shown in Figure IV-5,the boiler plant heating system consists oftwoWeil-McLain boilers with a rated output of 2,017 MBH (water)each.The boilers are manifolded together and tie-in to the heatingsupplylinetothefivemainbuildingsthroughamotorizedmixingvalve(currently not working).Two 130 gallon expansion tanks suspendedromtheceiling,(each 6 feet long by 2 feet in diameter),provideexpansioncapacityforthisloop. The Day school heating supply line is directly off the boiler supplyheader(not through the mixing valve).Two Grundfos 2.50 LM8circulatingpumpspipedinparallelprovidefor100%back-up capacity.A 90 gallon expansion tank (2 feet diameter by 4 feet long),connectedviaanairscoop,provides expansion capacity for the Day schoolheatingloop. A 500 gallon hot water generator (3 feet diameter by 10 feet long)islocatedintheboilerplantadjacenttotheboilers.The hot watergeneratorprovidesforallthedomestichotwatercapacityofthe sixmainschoolbuildings. Chevak Waste Heat RecoveryReportandConceptDesign Figure IV-4 Chevak Day School _wai Figure IV-5 Boiler Plant Heating System 11Q2\IT0581(6)1s Bama a Nane nna nantenn T_THH UTILIDBUCTAL 5 CHEVAK SCHOOL FAN ROOM #3(WASTE HEAT TIE-IN) 300°RUN 42 1/2"ARCTIC PIPE \escre PIPE SUSPENDED BENEATH SCHOOL FLOOR JOISTS iN CRAWL SPACE (SEE NOTE 1) 4 | Le | SPAN GUY ROAD be--= || ||WASTE HEAT|EQUIPMENT PLATFORM (NEW)| |HUSSMAN MODULE---_ 4”PRIMARY SUPPLY &RETURN (TO HEAT EXCHANGER)(NEW) BUTLERaLaate a : rj...[PaaS |57 9PAGEtemy}44-----55-5777 TTF ae *PAILERZz- 4i4-4-----|2 |a |z |! 8 io SCHOOL TANK ;FARM |AVEC PLANT SITE SITE PLAN SCALE:1”=60'(APPROX.) NOTES: 1.PIPING RUN IS 300°ONE WAY 2.600°OF 2 1/2"ARCTIC wee PIPE REQUIRED Paty State of Maeno .BS Alaska Energy *cont,FOU East *o.4LEGEND:pncrerages mowe wis easy Project -------EXISTING POWERLINE CHEVAK WASTE HEAT WASTE HEAT LINE Title - e POWER POLE SITE PLAN Aa Bui [Drown aeak Sate [oote j BILE NAME.CHEVSITE no [oats Reveion Dy VordFleNome tee oo FAN ROOM #3(SEE FIG.V-5)-s-Tr rT 7 | | 1 | | ;-9 | 1 s-o |!| ---_-Lo |_J HUSSMAN MODULE (SEE FIG.V 3)_--4 BUTLER BUILDING (SEE FIG.V-4) aw 7_ 68°RUN OF 4” PRIMARY COOLANT PIPE aNN WASTE HEAT EQUIPMENTPLATFORM <<lanTN spo RUN OF 2 1/2”ARCTIC PIPING Stote of Alaska Alasxa Energy AuthoritaN|P.O.box Ve0869 y 701 East Tudor Road Anchorage,Alaska 99519-0869 Project CHEVAK WASTE HEAT Title SYSTEM PIPING SCHEMATIC wee ne Orawn TUW Approved A.E.A.No. y ")Designed ScaleV-?2 FILE NAME:CHEVSYPI Checked Date 3/91 Sheet 1 _of 1 DRUM STORAGE HUSSMAN MODULE EXISTING RADMOR --,_ l [ {}|rij-,:;|bad '-----_-_-_--_ >rq>--4 POSITION #4 Cat 03412 Saino Tue HEAT EXCHANGER (AMOT NOT SHOWN) U- -_-----_---_ f 1|[in FLOOR PLAN SCALE:1/f'=1° EXPANSION TANK (NEW) EXPANSION TANK TO BE MOUNTED al CitS/o ABOVE PPG a cALoM a1OBURENBULK'age eeeUH.§t --e Ss oyviHYDRONICSFROM|a x wx 21/2 |$<EXISTING SHELL AND TUBE HEAT EXCHANGER WAS 21/7 4.|| our PN ae ETE =it|jp 2 SES - ry Nuc.RETURN FROM--_weaT TO RADIATOR |-”MOTOR \ -gH\'ve .wee| AAA fr STING RADIATOR -_- Posmon #4 HUSSMAN MODULE PIPING SCHEMATIC03412NOTTOSCALE EQUIPMENT SCHEDULE:LEGEND:Alaska Enerte2 imo, PLANT PIPING |4"_STEEL,WELDED TAY CHECK valve BS 700 Coeant 2, AMOT VALVE 480C 18001 ><]ore ae Anchorage,woe 444 +Are Project ,:Lae LOW COOLANT LEVEL GAUGES:[4]SuTTERFLY vave CHEVAK WaArit MURPHY LOW WATER LEVEL Bed AMOT VALVE Te HUSSMAN Molto EXPANSION TANK:10 GALLON PS ee .FLOOR PLAN/P Ist =WiDesignedtseuie" NV FLEXIBLE CONNECTOR No.[ote 12-10-90 Checked Toate "eet FANS AND PULLEYS REMOVE EXISTING RADIATORS, BUTLER BUILDING FUTURE LOCATION OF SECOND RADIATOR -_J PLATE ANO FRAME HEAT EXCHANGER WASTE HEAT RECOVERY EQUIPTMENT PLATFORM (NEW) ---}L.a7 ;co 1 ive \ro) !z!POS #1 ra)Pos #2 !D353 g 5 0342 |Be |!af| j ( | | ..-]C »a Oia\1 1 Me FLOOR PLAN SCALE 1/8 =1° MANIFOLD WILL BE PROVIDEDWITHVALVESANOBLNO FLANGES FOR FUTURERADIATOR MwC 86005 WITH--2 SPEED MOTOR FROM HUSSMAN TO HUSSMANNfSNHHEATEXCHANGERfag ipaeeiee teeter 800,000 MBH HEAT 5URPLif(PRBIE SERSOTETUN So Nhe SEW OP|it tyeeeej -|N.C.| ---P--------------bee eS - EXPANSION TANK Tcm-weet aaa \,V5 CAL (NEw)BUTE BLOG.ADVE”L .LOW COOLANT__ig ne.LEVEL SHUTDO!r ns.-_x i3/#BYPASS UN || |||?EXISTING HEAT =++2||TO BUILDING -FROM BUILDINGHYDRONICSHYDRONICS |rine qLboot1|Lb obIt 1 t I t !t l !l l |i ! ]|'I LJ I { D353 peuocart 0342 | EXISTING HEAT |__(VACANT)t POSITION #1 EXCHANGER TO POSITION #2 |POSITION #3 |WAL L- -----4 BUTLER BUILDING PIPING SCHEMATIC NOT TO SCALE Stare EQUIPMENT SCHEDULE LEGEND:eN |Alaska ©.=,>HEAT EXCHANGER 800,000 BTU/HR]PJ CHECK VALVE Anchors se ane -APV_3 CHAMBER tx]GATE VALVE Project .aREspeeyMatoSeas1BUTTERFLYVALVECHEVAK#4 1AT _ PLANT PIPING 4°STEEL,WELDEO Title BUTLER *-no AMOT VALVE 4B0C_18001 bd MMOT VAM FLOOR PLAN,fi fF MATIC EXPANSION TANK _15_GALLON |CIRCULATING PUMP DraenSAA [Approves ++sa none LOW COOLANT LEVEL GAUGES Designed Scale .MURPHY Dw.cauce era 1so-Kt|AAA mpcate convecror FE NAME:CHEV-BUT [No Datel T2=10-90 Checked Date _Ff a Chevak Waste Heat RecoveryReportandConceptDesign VI.Failure Analysis A.Introduction The purpose of the failure analysis is to predict the operational reliability of asystem.It provides an overview of the probable type and frequency of failuresandindicateshowthesystemshouldbedesignedandmaintainedforoptimal reliability. A waste heat system depends on a number of components to provide heat totheuser.To the greatest extent possible,the system should be designed sothatfailureofoneportionwillnotdisabletheentiresystem.Equipment withmovingparts,such as pumps,are generally less reliable than static equipment,such as pipes and valves.For this reason,it is common practice to installredundantequipmentforitemswithhigherfailurerates. Ultimately the dependability of the system relies on the operation andmaintenance,which cannot be effectively predicted.Implementation of agoodmaintenanceprogramandthoroughtrainingofoperatorscangreatlyincreasethesystemreliability. B.Failure Modes and Impact 1.Generation System a.Components: 1.Engines:The engines are the source of heat and must be.running at normal operating temperature to provide heat.TheAVECpowerplanthasoneenginerunningcontinuously,andtwoonstandby.Sufficient standby capacity exists to allowcontinuousoperationduringperiodsofscheduledmaintenance,therefore,a dependable heat source should be available exceptduringanenginefailure. 2.Cooling system:The engine cooling system consists of radiators,the primary heat exchanger,piping,and associated valves.TheradiatorsinChevakhaveprovidedgoodreliability,however,radiators are prone to failure.Use of independent radiators tortheButlerbuildingandHussmanmoduleandisolationvalvesminimizestheimpactofradiatorfailure. Chevak Waste Heat RecoveryReportandConceptDesign b.Failure Modes: 1.Failure or shutdown of the engines will stop heat production anddisablethewasteheatsystem.Controls are installed to shutdowntheenginesintheeventoflowcoolantlevelsorhightemperatures.Alarms are installed to alert the operator prior toautomaticshut-down.This allows the operator to attempt toisolateorbypasstheproblemorbringastandbyunitonlineasappropriate. Radiators usually fail by coolant leakage from cracks which arecausedbyrapidandextremetemperaturechangesorvibration.Generally,radiator leaks are small and result in a low coolantlevelalarm.The system can continue to operate after isolatingthefailedradiator. The primary heat exchanger provides separation of the fluid intheenginecoolingsystemfromthefluidinthewasteheatdistributionsystemsothatafailureofthewasteheatpipingwillnotcauseenginefailure.The heat exchanger is composed of aseriesofformedstainlesssteelplateswhichareseparatedandsealedbyrubbergaskets.The plates are bolted together within asteelframetocompressthegasketsandholdtheplatestogether.The most common failure mode is leakage due to failed gaskets.The leaks are generally slow and can often be corrected bytighteningtheframe.Occasionally gaskets may requirereplacementwhichwouldtemporarilydisablethewasteheat system. Piping failures can occur due to failure of joints or the pipe itselfduetovibrationorexcessivestress.A broken pipe or joint couldcauseasuddenlossofcoolantandsubsequentshutdownoftheengines.The use of welded steel pipe,installation of vibrationisolatorsatconnectionstoequipment,proper layout to allow forthermalexpansion,and proper support will greatly reduce thechanceofpipingfailure. Minor leaks from valves or connections to equipment can causeslowlossofglycol.These problems can usually be corrected bytighteninganddonotnormallyrequireshutdownofthesystem. c.Impact on the Generation Plant Operation: 1.A large,sudden loss of coolant from the radiators,piping,orprimarysideoftheheatexchangerwillcausetheenginestoshutdown.Since the cooling system for the standby generators ispipedindependentlyoftheprimegenerator,power could berestoredassoonasthestandbyunitcouldbebroughtonline. A slow leak in the cooling system could result in a shut down oftheenginesduetolowcoolantlevel.If found in time,the leakingitemcouldbeisolatedwithvalvesorrepairedandcoolantaddedtothesystemwithoutanyoperationalimpact. Chevak Waste Heat RecoveryReportandConceptDesign d.Impact on the Waste Heat System: 1.Asmall leak on the primary or engine side of the system will notaffectoperationofthewasteheatsystemunlessitisallowedtocontinueuntiltheenginesshutdown. 2.Alarge and sudden leak that resulted in engine shut down woulddisablethewasteheatsystem. e.Environmental Impact: Failure of the cooling system could result in a large glycol spill whichcouldcontaminatethegroundnearthepowerplant,nearby surfacewater,and the ground water.Use of propylene glycol would greatlyreducetheenvironmentalimpact. f.Required Immediate Actions: Determine the location of the leak,isolate the affected components,add coolant as required,and clean up any spilled coolant. Distribution System and User Connection a.Components: Connection of the user building heating system to the waste heatdistributionpipingwillbeaccomplishedbydirecttie-in to the boilerplantheatingreturnline.Valves will be provided for isolation of thewasteheatpipefromtheschoolheatingsystem.Two circulatingpumpsandalowpressureshut-off switch will also be included. 1.The transmission piping will consist of a welded steel carrierpipe,urethane foam insulation,and a high density polyethylenejacket.The pipe will be buried about 2 feet deep in the groundbetweenthepowerplantandtheschool.The pipe will besuspendedfromthefloorjoistsintheschoolcrawlspace. 2.The circulating pumps will be canned-rotor type centrifugalpumps.This particular type of pump is quite dependable,however,to ensure continuous system operation two pumps willbeinstalledtoprovidebackupcapability. 3.The low pressure shut-off switch will be of industrial quality withhighreliability. 4.The three-way,two-position valve will have a spring return to thenormallyclosedpositionsothatonlowpressureshutdownthevalvewillswitchtoisolatethewasteheatsystem. 26 Chevak Waste Heat RecoveryReportandConceptDesign Failure Modes: 1,Failure of the piping could occur due to corrosion,mechanicaldamagefromexcavationequipment,failure of welds,or damagefromfrostheaveorsoilsettlement. The pumps can fail due to corrosion,broken seals,motor orimpellerfailure,corrosion,or loss of electrical power. The low pressure shut-off switch may fail due to corrosion or lossofelectricalpower. The three-way,two-position valve may fail due to loss ofelectricalpower,or actuator or linkage failure. Impact on the Generation Plant Operation: Failure of the transmission piping or pumps would have no impact onthegenerationplantoperation. Impact on the Waste Heat System: 1.Minor leaks in the piping would have no significant impact on thesystemoperation.Glycol would need to be added as the systempressuredroppedduetoleakage. Larger leaks which cause a measurable loss of glycol and loss ofpressurewillcausethelowpressureshutoffswitchtoshutdownthepumpandthethreewayvalvetoswitch.This willautomaticallyisolatethearcticpipeloopfromtheschoolheating_system.The isolation valves can be closed to ensure completeisolationofthewasteheatloopfromtheboilerloop.Once theleakwaslocatedandrepairedthesystemwouldbebroughtbackonline. Failure of the lead pump would render the system inoperative.Upon detection of the pump failure,the standby pump could beactivatedandthesystemwouldreturntonormaloperation.Thefailedpumpwouldthenneedtobereplacedbutthiscouldbeaccomplishedwithoutsystemshutdown. Loss of power or failure of the low pressure shut off switch willcausethethree-way valve to switch and the pumps to shut downautomatically.Upon detection of the failure,the system pressurewouldbeverifiedandthepipinginspectedforleaks.If the valvewasdeterminedtobefaulty,the valve could be isolated andreplacedorrepaired.If a leak was found,the pipe would berepairedandthesystembroughtbackuptopressurepriortorestartingthesystem. Chevak Waste Heat RecoveryReportandConceptDesign e.Environmental Impact: Glycol leaking into the ground could contaminate the surroundingsoil,nearby surface water,and the ground water.Use of propyleneglycolwouldgreatlyreducetheenvironmentalimpactofapipelinefailure. f.Required Immediate Actions: For minor leaks add glycol as required.For major leaks isolate thepiping,determine the location of the leak,excavate (if required)andrepairthepipe.Recover any spilled glycol. C.Failure Frequency and Cost The most common modes of failure are listed below,along with estimates ofthefrequencyofoccurrence,repair cost per occurrence,amount of downtime,and a description of the effects on system life.The average annual costtoperformtheserepairsisestimatedat$1,150 per year.It should be notedthatmaintenanceofcertainitemswillrequirethatthesystemberemovedfromservice.This maintenance can often be scheduled during a period whenthepowerplantisoutofserviceorwhentheuserbuildingdoesnotrequireheat.Therefore,the potential loss of energy sales during routinemaintenanceisnotincludedinthecalculations. 1.Generation Plant:The most common form of failure is engine failure.Frequency is variable but outage time is estimated at less than 24 hoursperyearasthreegeneratorsareavailable.Repair cost is $0 as it is notrelatedtothewasteheatsystem. Power Pant Heat Exchanger:The most common form of failure is failureofgaskets.Frequency of occurrence is 5 years.Down time is 4 days andrepaircostis$3,500.There will be no measurable effects on system lifefromrepairs. Circulation Pump:The most common form of failure is motor orimpellerfailurewhichrequiresreplacementoftheentireunit.Frequencyoffailurewouldbe10years.Down time is less than 24 hours since abackuppumpisprovidedandrepaircostis$1,500.There are nomeasurableeffectsonsystemlifefromrepairs. Distribution Piping and User Building Connection:The most commonformoffailureisfrompoorinstallation.If properly installed thefrequencyoffailurewouldbe10years.Down time is 5 days and repaircostis$3,000.There are no measurable effects on system life from repairs. D.Design Decisions Made to Minimize Failure Rate and Impacts 1.Heat Exchanger:The use of a heat exchanger at the power plant allowsforindependentoperationofboththegenerationsystemandtheuserbuildingheatingsystems.While this does not decrease the failure rate itdoessignificantlyreducetheimpactofafailure. Chevak Waste Heat RecoveryReportandConceptDesign Duplex Pumps:The use of duplex pumps allows normal systemoperationtocontinuewhileareplacementpartisordered.This enhancessystemreliabilityandreducestheimpactofafailure. Isolation Valves:The installation of isolation valves and,where required,bypass valves at all major system components allows for immediatecorrectiveaction,minimizes the effects of partial system failure,andenhancesmaintenance. Welded Steel "Arctic"Pipe:The use of welded steel "Arctic"pipe for thedistributionsystemgreatlyreducesthelikelihoodoffailure,particularly intheexterior/buried distribution piping.In the case of a break in theipingandlossofpressure,the three-way valve would isolate the wasteheatsystemfromtheschoolheatingsystem.An alarm would be triggeredbythelow-pressure shut-off switch and notify school maintenancepersonnelofapotentialleak. Welded Steel Primary Cooling Pipe:The use of welded steel pipe for theprimarycoolingsystemgreatlyreducesthelikelihoodoffailure,particularly in the exterior Chevak Waste Heat RecoveryReportandConceptDesign VII.Project Specifications A.Codes and Regulations The listed versions of the following codes and regulations were used in thepreparationofthisreport: o Uniform Building Code (1988) o Uniform Mechanical Code (1988) o Uniform Plumbing Code (1988) o Uniform Fire Code (1988) o National Electric Safety Code (1987) B.DIVISION 01 -General Requirements This is a general information section covering the coordination of work,description of the work required for this project,regulatory requirements,definitions,payment procedure,submittals,quality control,materials andequipment,starting,testing,contract closeout and maintenance. C.DIVISION 02 -Sitework A.This section describes general requirements,products,and methods ofexecutionrelatingtoexcavation,backfill,and compaction of utilitytrenchesoutsideofbuildings. D.DIVISION 13 -Special Construction SECTION 13120 -Pre-Engineered Structures A.This section includes specific requirements,products and methods ofconstructionrelatingtothedistrictheatingmodulefortheproject. B.Waste Heat Module will be of wood frame construction insulated with fiberglass batt insulation,metal siding on exterior and sheetrock on theinterior. C.Support for the waste heat module will consist of a 5'by 20'steelchannelextensionoftheButlerbuildingfloorjoists. D.Snow hoods with back-draft dampers for both the exhaust and intakewillbeprovidedfortheradiators. 30 Chevak Waste Heat RecoveryReportandConceptDesign E.DIVISION 15 -Mechanical Outline Specification SECTION 15010 -GENERAL CONDITIONS This is a general information section correlating mechanical work to otherdivisionsofthespecifications,defining terms,referencing codes andstandards,itemizing submittal requirements,and defining submittals andinformationrequiredforoperationandmaintenancemanuals. SECTION 15050 -BASIC MATERIALS AND METHODS Piping inside and between the power plant buildings shall be schedule 40blacksteelwithweldedorflangedjoints.Piping inside the school FanRoom#3 shall be copper. Valves shall be 150 psig butterfly or gate. SECTION 15120 -ARCTIC PIPE Carrier pipe shall be black steel with welded joints.Insulation shall befoamedpolyurethane.Jacket shall be high density polyethylene.Arcticpipesystemshallincludekitsforbranchconnections,couplings,andchangeofdirection.I.C.Moeller Plus Pipe or equal. SECTION 15140 -CIRCULATING PUMPS Circulating pumps shall be system lubricated,canned rotor,centrifugaltype.Grundfos UPC 80 -160 or equal. SECTION 15160 -NOISE AND VIBRATION CONTROL All connections to engines and radiators shall be made with braidedstainlesssteelorrubberflexibleconnections. SECTION 15180 -INSULATION All piping within the power plant shall be uninsulated.All piping betweentheButlerbuildingandHussmanmoduleshallbeinsulated2”thick rigidfiberglasswithaweathertightPVCjacket. SECTION 15750 -HEAT TRANSFER Heat exchangers shall be plate and frame type with minimum 20 gagestainlesssteelplates,painted steel frame with head and end support,tapcarryingbar,and bottom guiding bar.Ports shall be 150#flange,orinternationalpipethread.Capacity shall be 800 MBH with two primarychambersandonesecondarychamber.Alfa Laval,APV,Bell and Gossett, Tranter,or equal. U Chevak Waste Heat RecoveryReportandConceptDesign SECTION 15850 -BALANCING AND TESTING The entire system shall be hydrostatically tested for leaks prior toinstallationofpipejointinsulationandcovers.The system shall bebalancedtotheflowratesindicated. SECTION 15900 -CONTROLS AND INSTRUMENTATION This section describes specific requirements,products,and methods ofexecutionrelatingtothetemperaturecontrolsandinstrumentationforthe project. Chevak Waste Heat RecoveryReportandConceptDesign F.DIVISION 16 -Electrical Outline Specification SECTION 16010 -GENERAL PROVISIONS This is a general information section correlating electrical work to otherdivisionsofthespecifications,defining terms,referencing codes andstandards,itemizing submittal requirements,and defining submittals andinformationrequiredforoperationandmaintenancemanuals. SECTION 16050 -BASIC MATERIALS AND METHODS A.A major part of the electrical specification,this section covers theworkmanship,coordination,and standards necessary for the electricalwork.The products covered include raceways,conductors,andconnectors.Installation techniques to cover various constructionmethodsarenotedsothatfireproofingismaintained,waterpenetrationandmoisturemigrationthroughracewaysystemsareprevented,and the proper connectors are used for various conductorterminationsandsplices. Only copper wires and cables shall be used.Raceways shall be rigidgalvanized,sherardized steel conduit or electrical metallic tubing withcompressionorsetscrewtypefittings,for all conduits concealed in thewalls,above the ceilings or exposed in work areas. SECTION 16130 -BOXES,CABINETS,AND PANEL BOARDS A.This is a general section that outlines various standards to follow in the B. construction of these items,with specific notation on certain types ofcabinetstosuitvarioussystems.Mounting heights for outlets andcabinetsarecoveredinthissection. Panel boards shall have copper busing with bolt-on type circuitbreakers. SECTION 16140 -WIRING DEVICES A.Receptacles,switches,device plates,and special purpose outlets arecoveredinthissection. B.All outlet devices shall be specification grade or better. SECTION 16150 -MOTORS AND CONNECTIONS Motor specifications regarding voltage,phase,and temperature rise arecoveredinthissection.Distinctions between which motors and control items are included in Divisions 15 vs.contract or responsibilities are alsoshown.Appliance and miscellaneous equipment connections,whetherowner-furnished or contractor-furnished,are covered to provide suitableconnectiontechniques. Chevak Waste Heat RecoveryReportandConceptDesign SECTION 16160 -MOTOR STARTERS AND DISCONNECTS Specific requirements for overload and phase failure protection to beincludedinmotorstartersarecovered.Also included is a listing of variousdevicessuitableforuseasequipmentdisconnects. SECTION 16180 -OVERCURRENT PROTECTIVE DEVICES This section contains a general listing of various devices suitable forovercurrentprotection,such as circuit breakers,fuses,and current limiters. SECTION 16190 -SUPPORTING DEVICES This section covers,in a general way,the various supporting,fastening,hanging,and securing techniques approved for use by the contractor in theinstallationoftheelectricalwork. SECTION 16450 -GROUNDING This section itemizes complete grounding requirements and techniques forconnections. SECTION 16480 -BRANCH AND FEEDER CIRCUITS This section clarifies drawing preparation technique as being diagrammaticratherthan"as-built"and gives the contractor flexibility in conduit routingandcircuiting,as may be determined by job site conditions. SECTION 16500 -LIGHTING A.Light fixture construction for both interior and exterior fixtures,lamps,and ballasts are covered in this section B.Interior light fixtures shall be fluorescent,of industrial design.Exteriorfixturesshallbehighpressuresodiumwallpackscontrolledbyphotocell M4 Chevak Waste Heat RecoveryReportandConceptDesign VIII.Project Cost Estimate A.Power Plant Heat Recovery System The first cost component is construction of the platform and module to holdtheheatexchanger,radiator and piping.This includes the mechanical andelectricalequipmentassociatedwiththemoduleandtheconnectiontothemodifiedAVECpowerplantcoolingsystemasshowninFigureV-4 on page 22. The second cost component is the modification of the existing power plantcoolingsystem.This includes the connection of Positions #1 and #2 via a 4"common manifold to one of the two primary chambers of the heat exchangerandtheradiatorasshowninFigureV-4.This also includes repiping theprimarycoolingloopforPosition#4 with 4"pipe and connecting it to thesecondprimarychamberoftheheatexchanger. B.Waste Heat Distribution System The connection of the school complex to the waste heat recovery systemincludesinstallationofthe"Arctic"piping from the face of the waste heatrecoverymoduletoFanRoom#3,as shown in Figures V-4 &V-5.TheconnectionatFanRoom#3 will incorporate valving to isolate the waste heatsystemfromtheschoolheatingsystem,as well as duplex circulating pumps for100%back-up capability.A three-way two-position valve will be used tocontrolthewasteheatsupplytemperature.A low pressure shut off switch willshutdownthepumpsandswitchthethree-way valve upon a loss of systempressureinthewasteheatpiping. C.Operation and Maintenance Costs Annual operation and maintenance costs are determined by the regularsystemmaintenancerequiredaswellasthenumberoffailures.Regularmaintenancewillbeperformedtwiceperyearbyaskilledmaintenancecrew.Daily operation will be performed by school district personnel.The averageannualcosttorepairfailureswasestimatedat$1,150 per year (see SectionIV.C.Failure Frequency and Cost).The cost of two annual maintenance tripsisestimatedat$5,000 per year and must be added to this failure repair cost.The total average annual operation and maintenance cost therefore is $6,150 per year. 35 D.Project Cost Summary Chevak Waste Heat RecoveryReportandConceptDesign Project costs for the proposed design are shown below: Table VIII-A Summary of Project Costs Outside Arctic Piping Installation $31,468 Platform &Module Construction $20,623 Hussman Module Piping Revisions $9,427 Butler Building Piping Revisions $33,905 Fan Room #3 Connection $9,871 General Requirements and Contingency $80,959 Total Project Cost (Spring 1992 Construction)$186,253 Total project cost includes design,supervision,inspection,administration and construction.The complete cost estimate isincludedinAppendixCofthisreport. Chevak Waste Heat RecoveryReportandConceptDesign LX.Conclusions A.Heat Availability &Fuel Consumption Thereis approximately 31,973 equivalent gallons of fuel oil per year availableaswasteheatattheChevakpowerplant.The waste heat recovery system candisplacethefollowingamountsoftheproposeduserheatrequirements: Table IX-A _Annual Heating Fuel Displacement &Pipeline Losses Item Equivalent Gallons Heat off Engines 31,973 Annual Heat Loss in Dist.Pipes 4,679 Heat Available to User 27,291 Bldg.Heating Fuel Required 52,000 Amount of Fuel Displaced by Waste Heat System 24,203 Percent of Available Heat Used 88.7% During the winter months the school complex would use virtually all of theheatavailable,as shown on Figure IX-1.aonn.NOooOoOOooOoOoOoOoOoBNHeal(GallonsofFuewi>aro)o666Jan Feb Mar Apr May June July Aug Sept Oct Nov Dec Month -*-HeatDemand ZZ Heat Displaced Figure IX-1 Heat Demand vs.Heat Displaced 37 Chevak Waste Heat RecoveryReportandConceptDesign B.Project Cost Summary The school paid $1.06 per gallon for heating fuel during 1990.The annualsavingsiscomputedusingthesecostsforheatingfuel.The following tablesummarizesprojectcostsandsavings: Table IX-B Project Summary Amount of Fuel Saved 24,203 Annual Savings $25,655 Total Project Cost $186,253 Straight Pay Back (yrs)7.3 C.Project Summary The practical useful-life of a waste heat recovery system is related to theavailabilityofwasteheatfromthepowerplant,the need for heat at userbuildings,and system maintenance.The long-term outlook for the availabilityofwasteheatfromtheAVECpowerplantandtheneedforheatbytheschoolisgood.With proper maintenance the life of the waste heat recoverysystemwillexceed25years. Because annual operational and maintenance costs and economic decisionswillbemadebyABA,final economic conclusions are not presented in thisreport.The straight payback time for the project,is 7.3 years. Chevak Waste Heat RecoveryReportandConceptDesign X.Recommendations One way to make the project more economically attractive is to reduce its scale byminimizingnewconstructionandrenovationsatthepowerplant.Anotherapproachwouldbetocombinethisprojectwithwaste-heat projects in otheresternAlaskacommunitiestoreduceChevak's share of the high mobilization,shipping,travel,and supervision costs required. MG APPENDIX A Calculations Chevak Waste Heat Power Plant Heat The amount of heat required to keep each power plant building at 65°F wascalculated.The number of air changes in the building was assumed to be equal totheamountofcombustionairrequiredbytheenginesplustwoairchangesperhourforboththeButlerbuildingandHussmanmodule.e conduction heat loss wasthenaddedtotheinfiltrationheatlossandtheamountofheatrejectedtotheambientairofftheenginesubtractedtocomeupwiththehourlyheatrequirements for the power plant. User's Monthly Fuel Oil Usage The annual fuel oil usage,as obtained from the school district,was distributed bybuildingover12monthsusingthenumberofheatingdegreedays(HDD)as follows: (Monthly HDD)x (Annual Fuel Consumption) Total Monthly fuel oil usage = (Annual HDD ) (Building Area)x (Total Monthly Fuel Cons.) Monthly Building usage by Bldg =---- (Total Area of School Bldgs ) Available Waste Heat &User Heat Displaced The amount of waste heat available at the power plant and the amount of heatrequiredbytheuserwerecalculatedusingacomputermodelwiththefollowinginputandassumptions: 1.Historical monthly power generation data for the power plant,annual users'heating oil consumption,and monthly heating degree days were input. 2.The amount of heat available off the engines versus power production,from theenginemanufacturer's data,was input. 3.The heat losses for the proposed piping system,plant heat,etc.were input. Appendix A Page Chevak Waste Heat 4,The hourly diurnal power generation variation per month and the hourly diurnalheatingrequirementswereinputtodistributethepowerandheatdataoveraone-year period in the model. 5.The amount of heat usable by the proposed users is summed up for each monthtodeterminetheequivalentnumberofgallonsofoilwhichwillbedisplacedbythewasteheatrecoverysystemeachyear. Program Notes: a.The amount of heat available off the engines listed in Table III-B is from theenginemanufacturer's engine specs. b.The assumed heating value of a gallon of oil is derived by utilizing a 73%burner efficiency with 134,000 BTU/gallon oil to arrive at equivalent of98,000 BTU output per gallon of oil. Appendix A Page Chevak Waste Heat APPENDIX B Field Trip Notes WASTE HEAT UTILIZATION SIMULATION WORK SHEET. Location:Chevak April 18,1991Date: Annual O&M cost: Cost Estimate Fuel heat value: Fuel cost Fuel cost escal. Power increase Discount rate GENERATOR DATA: Heat Heat Heat Heat Heat Heat Heat Heat Heat Heat Heat rate rate rate rate rate rate rate rate rate rate rate at at at at at at at at at at at kw-load kw-load kw-load kw-load kw-Load kw-load kw-Load kw-load kw-load kw-load kw-load GENERATION DATA: Kwh/month: Janua ry February March April May June July Augus t September October November December 1 6150 $/year. 125000 $ 134000 8tu/gall. 1.06 $/gallon 0.02 /year 0.02 /year 0.04 /year above: above: above: above: above: above: above: above: above: above: above: 119080 105720 106440 86680 86400 67440 75280 90320 89400 107600 111120 116720 162200 PROGRAM RESULTS: C (Savings,year 0,gallons:24204 [ ly[10 year B/C ratio:-0.3 [20 year B/C ratio:-0.71 (Pay back time,years 0.00 C SYSTEM LOSS DATA: 3200 8tu/kwh Constant losses: 3200 8tu/kwh Plant piping: 3200 Btu/kwh Subsurface piping: 2700 Btu/kwh Engine preheating: 2600 Btu/kwh Total constant: 2400 Btu/kwh 2400 Btu/kwh Variable losses: 2400 Btu/kwh Surface piping: 2400 Btu/kwh Plant heating: 2400 Btu/kwh Radiator losses: 2400 Btu/kwh Total variable: WEATHER DATA: HDD/Month: 1804 1565 1659 1146 775 372 326 381 591 1029 1440 1792 9625 Btu/hr. 0 Btu/hr. 0 Btu/hr. 9625 Btu/hr. 137 Btu/hr.xF 465 Btu/hr.xF 50 Btu/hr.xF 652 Btu/hr.xF plant and secondary Butler Bldg Inside Hussman plennum Ceca Motes CHEVAE 19/9) Khe monmami or Senep/Me%AC bes.1225 SS -97714,3 FAY 85%-I+)het Spee MH Emiey Vienic «Tee.Pawiyak -Pasar déaT PreinesaaJGnaciusCHAYALKUN-Vice CHIH Imo re'n Pius Imenteex -Sead, Geeser;HLORALREA -Tpaxsveéee VD a CA -MEnbE® Schoo!Bly Inf * .Al li -Acta Spee side Re bn fol?bton a za _holens ee penple -Plurhow 'yw schiook¥peAlbertULRORN-teipa2 A ety BR teal wedlokreon-machanrz,_(Bue Rae bere 1 CT tk -welpe,° Jalan CHE YA Die Se toed Ske pue st Com t'<gp US Rept of Bong SEOSire ype Aran OFF PUA MET Deum Iolerl ryCVSSizl2/@2V 4oi/zi/@2 -Sa rearesl Bidg-Ase we ChHécak Areustee @.RL +>shod Poms -OTHE AL Men ARH TeeTHRAL Gd Ent Berne CO Pace >al 6603 DBy :€.0 ' ”Pepva >ASFL -\Zoe WES reo fo Ab wea see) pve S bbe Climate {'* Dehw- SU LYEE0 7165 tye.CCDBIYAWDEBayeVERSRotlockPeaslook|Rec aexvece AECY Cleles 442 >--- Isloi]Zoo psi} Zn)can'!orey Teo dere celeek noe legTCOIOD:bybanbroncgp TC -O Dampee Te-7 eve fut oP Lo?7O° 0)O 2lato3°75” 4 ee Se!oP Cal sperlel _\b oF one -_Lots of 6 tov we hOMe (200Z)pp pak GyMm -Cla Ut Va2Z2>S 2S'oe Det Pp o'e CnwAry --Unde Lleoe HAS Ply wooo Shah,2 2_Joie -Tdisto2 27%!Hao ws /(Aiki Pipa 4 Cendor-Cun weet Rerveak sub Gy A/Stroot FE 245%Lenn Util DeeTym sod >Anv*3GeHOST Lots ff alee Ortleatsplelite 1%CMEC LE Atos| ottlOOAOwTrecae-Tc pad aTS-(=O° TC Seredweé:%$-2<-65° orp OFFmM74Z2'985T71WwWS3S TH Ss ' FE b 3 Ss iy (2 an --Un {7”pntyy IAB pvt Sk Tew =EE°r |oda:-17F}ook®(2 <¢71°F 6",y of IF 3"2° IO S*AHue C7 Tne'lock _To nk Te-3°2 Or Of E +s-Yx 62° yn G Pr }1 7% T on 10&L/Gr Hoo Tr Om 15-a 12%y ?-- Sa Mia DP 47 rODAj Dpee cha fA 77 fish,yy-32 Plinth pra -S?”/5D Gi,a 'Shins sPevAi €&&-7-F por pre to [ns Ap SearsGyoApen? _Bo amey vahe -stl MXC N06btvabengt roattiny 4 "retatfzopenPAekyfor=!pr 7 Pel Tena px pl UL.@ 2m éile 1" Supply temp vate,[bo ieore Vela 256p =AVEC Rete Pldq @ CHEWHLWinnsSK Jo Dim's (Intense [Pay ee > Re ABmer 2Rothew?|_aos - wl of :\ .O Goeth/(Ray tankHe|i | 1 'x37"Feces Waal)EXTbodsPat*t C3)357 o 2%P >|tee.(2.Flam cige tf wooty CL-S5 (a Fifea SOPQle Gaat>nale S39e%se ay wore sency |@<«s'wav ats |4+UN +/1 Z8 -1,=z Pe 297357 3 e < mé CI-ss iy 7 2 Sa S3909/9 L \A Ak Da jtane We Z yt2,, UY Y 52 "Te Siw wa)HTR on S +3 x§255 OB aw za Allg 327%>(.9 ¥pe ott Pos har &Z =aad 3FleeWtttortNetw)OZ As1Sama)ST4 Xo £o@ ez m &st €=\EF <.Ohn aL CRi PANO?)se win 2]3 seida_I en Flat Block i 0e,2- 30%" Flave iS ow,POdINon | 1 OFF Lin€3a0kw D353| ”Y, }: ;SWITCH GEAR L (t \ WhalerZa-72-id =Fe ee -KE HF w/e ee a?\a ] Pxaieliord 4-7 Adda erqew IWS %&"Bod 940 SS cen 2:35p -309 CHEVAC _tvec Sex a ila7/au Beg Dimas 23'6"ex Gew X9'eT 6CnGaun2 Pind 1 L HU ow)nie \Low Be EZ2ko) Yours Pavia be \Se7 dye jf VOL*sS <=Sit0 ¥ Wow .hen ot as £$ Sup 434 'c 8 fe | 5 .A pred Ge "or33rp'oo . ; --Dao .+-Say |oSxri% x ; JB|nm e §oy "As wW "i -!- nN c 4 3fe+=+< x, ChELASY Hessen pnajele Avec. )fi9/4 7 - PUP Scdnde HA DRursic Pid scdecanter ' ay#Y-PSLa-_Tr,':|a |:aoece| Kor (TT |}ant | ---Je ('-_s5 Td fle antoHOC+yP -8 |,|vi,C -207Y ;rom Tr L cotWM"'7 {(2402 yo.soe 22.ang for San fies s E lovashien bs (tne =3 3%Sade IM Yat! bee a Seen Tae etZn >Grom Pat Breas -Inemrcde2106%-o-157 Be Mig¢Zane lo GPR _*FO Sina yl HVE GeF 7 Hr P hz 2'>Mee -a ,r?,Bo .'cod |!! \WAit-Me lAnN $:2¢@ enedsaey ope: _T-.=I fay:y 4N_= sy +1 [ x +4 1S psi Y <bes:isp” ae vla-ns ew Mt $c 2 aM 15d Sc) 2 /Kb S .PD enego2d. 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