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HomeMy WebLinkAboutCity Tribe Biomass Energy Conservation R3 Trip Report Tanana Biomass Improvements 2023 MEMORANDUM DATE: Jan. 24, 2023 FROM: Utility Operations Specialist IV SUBJECT: Trip Report, Tanana – Biomass Energy Improvements, AKAZA2-0999MTS/ TALZ87-1130EEO – Jan. 26-Feb. 11, 2023 TO: FOR THE RECORD OBJECTIVES:  P rovide biomass energy improvements outlined in the May 2022 Rural Alaska Village Grant (RAVG) biomass energy audit recommendations.  Provide on-the-job training to the operator on Garn biomass boiler system operation and maintenance.  Follow up on operational status of the recent Infrastructure Protection Fund (IPF) improvements installed in December 2022 CONTACTS: Mr. James Roberts, Water Plant Operator, Tanana Too’gha Inc. Ms. Gladys Erhart, Finance/Administration, Tanana Tribal Council (TTC) Mr. Cliff Wiehl, Too’gha Maintenance Manager, TTC Mr. John Erhart, Maintenance, TTC Mr. Victor Joseph, Executive Director, Tanana Chiefs Conference (T CC) Mr. Kyler Charlie, Local Laborer, T T C Mr. John Walsh, Local Senior Laborer, T T C Mr. Hal Hail, Local Laborer, T T C ACCOMPANIED BY: Mr. Tory Adams, Utility Operation Specialist Assistant, ANTHC Mr. Kameron Hartvigson, Utility Operations Specialist III, ANTHC FINDINGS AND ACCOMPLISHMENTS: Mr. Tory Adams and I departed Anchorage at 11:05 a.m. through Fairbanks via Alaska Airlines and arrived in Tanana via Wright Air charter at about 3:15 p.m. Jan. 26. Charter flight was required as we were traveling with excess of 1,200 lbs. of boiler parts, replacement bricks, plumbing materials, personal tools and additional gear. Upon arrival, we were met by Mr. James Roberts and Mr. Cliff Wiehl at the airport. We unloaded the plane and transported all items to Trip Report, Tanana – Biomass Improvements Page 2 Jan. 26-Feb. 11, 2023 the water treatment plant (WTP ) and Garn boiler facility. The weather was overcast and the temperature was about 10°F. We set up lodging at the tribe’s Detour Inn. Mr. Adams and I met with Mr. Roberts at the WTP/washeteria to discuss the tasks and scope of the trip. Mr. Adams and I then went through and unboxed all the freighted items and worked to stage, organize and inventory the materials to specific locations in the WTP , washeteria and biomass facility. I called around to locate a local pressure washer, pressure hoses and vacuum cleaner. We started setting up for Garn boiler cleaning. Using surplus 1-inch PEX tubing left over from the 2020 clinic service line work, we installed a temporary water feed service line from the WTP utility sink area to the bio mass boiler building. The line was routed from the WTP mechanical room and through the supply and return heat utilidor arctic carrier pipe. The line was not directly tied into the potable water system, but set up to be manually connected to the utility sink faucet by means of a washer hose. The utility sink has an integrated vacuum break to prevent cross- contamination concerns. RAVG Biomass Improvement Priorities Improvements Note: Due to limited funding and potential unknowns while performing work, recommendations were prioritized. Completion of tasks was based on labor assistance, seasonal weather limitations, available funding, and time schedule constraints. Recommendation 1- Boiler Water Improvement  Remove all water and sedimentation from biomass system, and pressure wash and clean interior. Completed. A layer of calcium deposit scaling approximately 3/16-inches thick was discovered inside of tanks on the burner chamber wall and hot vent piping near the fire box. The buildup was not as thick on the vent piping farther away from the fire chamber and was easier to clean. We resorted to manually chipping off the deposit with a hammer and chisel in order to improve the heat transfer. This was a very slow, labor- intensive task. The pressure washer could not break up the buildup, and a grinding wheel generated airborne dust and particulates. Water spray mist was used to control dust.  Clean and rotate inline strainer and add pressure gauges up- and downstream. Completed. The strainer was opened and discovered to be almost completely clogged with black/tan tar-like substance. The strainer screen was cleaned and re-installed. Access for cleaning was greatly improved with ¼-turn resetting of strainer. The gauge ports were drilled and tapped into housing up- and downstream of the screen for monitoring.  Install bypass filters and fill point and provide spare filters. Completed. Three cartridge filters were installed to remove particulates from the biomass water. The filters were installed immediately upstream of the biomass plate and frame heat exchanger in the WTP . A Grundfos Alpha pump circulates the water through a secondary loop off the main line. The three filters are installed in parallel with each other in the secondary loop. Spare filters were provided and stored on the top shelf above the workbench. An operational wall chart for monitoring the filter differential pressure and replacing the cartridges will be sent to the operator. Trip Report, Tanana – Biomass Improvements Page 3 Jan. 26-Feb. 11, 2023  Install new manway covers, gaskets and low-water cutoff sensors. Completed. Three newer two-piece hatch covers were installed with new level sensors.  Repair leaky fitting in WTP boiler room. Completed by others/contractors.  Remove three-way valve, install three isolation valves, flush ports, pressure gauges and temperature indicator on hot side of biomass heat exchanger. Completed. Upon installing gauges, we immediately identified a 5 PSI pressure drop across the water side of the heat exchanger. The heat exchanger was disassembled and the plates were removed . The fouled plates were replaced. After reassembly, only about 0.5 PSI pressure drop was observed across the heat exchanger. Recommendation 2 - Airflow and Heat Loss Improvements  Insulate around dampers and reconnect combustion air ducts. Completed. The intake air return line manifold was lowered about 1¼ inches to allow more clearance. T he sheetrock covering near the intake area was removed to expose small area of the bare steel wall of boiler. We discovered 7x6x7-inch reducers had been installed on the damper vent ducts and were causing airflow restriction so we removed them. The 7-inch motorized dampers were refitted next to the boiler per the manufacturer’s specifications. The motorized damper on Boiler 3 was replaced. A small sealed foam insulation box was installed over the dampers on Boilers 2 and 3. The damper insulation box for Boiler 1 will be fitted and installed by a local worker. Two new motorized dampers were provided as spares.  Replace entry door with industrial door. Completed. The existing door was reused. The door and jamb were removed, adjusted and reset with a new jamb, hinges, strike plate and lock/latch with door reinforcement. The door was changed to a right-hand swing for inside light switch access. The door still requires a metal base threshold, a bottom brush seal and outside trim. These remaining items are to be installed by the operator.  Isolate unused boilers. Partially completed. All boilers can be isolated, however the heated mass of Boiler 3 is beneficial for longer heat cycles between firings. Any of the boilers may be isolated by closing the supply-and-return ball valves behind each boiler.  Provide brushes and clean fire tubes/flue pipes. Completed. Two rod sets and three sets of brushes were provided. We demonstrated how to clean the tubes using brushes and a vacuum cleaner. The replacement gasket sets did not arrive until the last two days we were onsite. Gasket saver kits were also provided but not installed yet. The operators were trained on the replacement of the gaskets and will complete the gasket replacement task. The three Garn boiler blowers and adjoining sensor ports were cleaned and the gaskets and gasket savers were replaced. The gaskets and gasket savers will need to be changed on all the remaining ports when the units get brushed and cleaned. Trip Report, Tanana – Biomass Improvements Page 4 Jan. 26-Feb. 11, 2023 Recommendation 3 - Freeze Protection/Re-Establish Backup Generator Operation  Level generator module. Not completed. This task was not completed due to snow and frozen ground conditions.  Reconnect fuel lines. Not completed. This task was not completed due to snow and frozen ground conditions. Flex lines were provided to the operator for fuel line reconnection work.  Replace battery for the generator. Partially completed. A replacement battery was provided but not installed. Oil and spare filters were also provided.  Establish schedule for exercising gen-set. Not completed. This task was not completed because the gen-set was not re-commissioned and is not operational. Recommendation 4 - Electrically Isolate Boilers  Confirm foam base under the biomass boiler. Completed. Foam exists under the boiler, however the boiler weight rests upon 2X dimensional lumber directly under the fork lift pick points. All three boilers are supported by a steel I-beam frame with three jacks under each end for leveling. Some leveling effort was performed to pitch boilers forward slightly to provide better draining. More leveling efforts should be conducted by the operators during the summer. Leveling the boilers is expected to be a seasonal task.  Install dielectric flange kits. Completed. Dielectric isolation already exists at steel-to- copper transition flanges behind boilers.  Install electric isolation kits on motor/control panel. Completed. Isolators were added on all three boiler motors. Two of the existing older blower motors were cleaned and set up for backup spares. Two more gasket savers are required for those motors. Recommendation 5 - Other Required Biomass Improvements  Establish testing and maintenance plan. Completed. All maintenance requirements for Garn units is outlined in detail within the boiler manual. Both electronic and hard copies were provided during December 2022 biomass training  Establish maintenance/cleaning schedule and provide wall charts. Completed. Provided both electronic and hard copies of the boiler manual during December 2022 biomass training. Additionally, Garn maintenance videos were provided.  Develop spare parts list. Completed. Provided both electronic and hard copies of the boiler manual during December 2022 biomass training. Reviewed a short list of items for the operator to maintain on the shelf. Ordering spare parts can be easily done via the Garn website. Trip Report, Tanana – Biomass Improvements Page 5 Jan. 26-Feb. 11, 2023  Replace broken fire bricks. Completed. The fire chambers in all three boilers were cleaned and new fire bricks were installed.  Replace lighting with LEDs. Completed. All three lighting fixtures were replaced with medium-base, screw-in LED shop lamp bulbs with directional light adjustment and switchable on-board occupancy sensing.  Replace attic vents. Not completed. A new vent needs to be purchased and shipped to the site for the operator to install. A hood should be added to cover the vents at both gable ends of building. Recommendation 6 - Other Recommended Biomass Improvements  Install pressure gauges downstream and upstream of bio mass heat circulation pumps manifold. Partially completed. Only one gauge was installed downstream of the pumps. The upstream gauge was not installed because the required fittings were damaged during shipment to the site. Spare gauges were left on the WTP workbench. The required fittings to complete the installation of the upstream gauge will be mailed to the site for the operator to install. The upstream gauges were installed as part of re-installed strainer recommendations above.  Replace Garn boiler door handles and hinge pins. Completed. All Garn doors were rebuilt with new gaskets (for positive seal), hinge pins, handles, and grade 8 latch bolts with safety pins. Three new gaskets should be ordered by the operator as critical spare parts and put on the shelf.  Provide moisture meter. Not provided. A meter will be purchased and shipped to the site.  Provide replacement gaskets for the biomass plate and frame heat exchanger. Completed. Both gaskets and a complete set of new plates were provided and installed. The old fouled plates were stored in a shipping crate. The fouled plates can be cleaned and reset with new gaskets when plugging next occurs and a change-out is required.  Add insulation to and weather seal garage door. Not attempted due to freezing winter conditions. Still need to order door brush seal. Additionally, the door rails and springs needs to be reset and adjusted. We observed the bio-building foundation has moved and settled over the years. The door brush seal will be sent out to the site for the operator to replace.  Add lighting at back side of boilers. Completed. The ceiling fixtures were replaced with LED fixtures and lamps. The new fixtures and lamps provide adequate light to illuminate the back of the boilers.  Provide shelving and workbench. Not attempted. The large Knack box or one of the existing shelving units on east wall will need to be removed to provide space for a workbench. Unistrut steel for a workbench build was provided. Trip Report, Tanana – Biomass Improvements Page 6 Jan. 26-Feb. 11, 2023  Re-integrate remote monitoring (RM) with Wi -Fi rather than cell data. Not attempted. The existing RM system is functional with current cell data. The existing plant Wi-Fi is slow and limited. T his could be upgraded if Tanana receives an upgrade to its RM system.  Replace pro -press copper pipe joints with solder fittings. Not attempted. A retrofit is beyond the existing RAVG budget. If the pro-press copper pipe fittings are removed in the future, the pipe and fittings should be changed out for PEX pipe to allow for the Garn boiler to move and flex due to observed boiler foundation concerns.  Replace wood walkway with metal alternative. Not attempted. A retrofit is beyond the existing RAVG budget. Used 3/4-inch plywood to build a working deck to support boiler cleaning.  Add insulation in attic. Not attempted. A retrofit is beyond the existing RAVG budget. After a building fire around 2019, the repairs to the ceiling sheetrock were poorly implemented. The ceiling sheetrock requires re-fastening to the rafters. Recommendation 7 - Other Recommended Biomass Improvements  Re-integrate existing solar-voltaic array system to biomass supplemental electrical heating elements system. Not attempted. Improvement is beyond the existing RAVG budget. Although this has great potential to reduce wood consumption during late spring, summer and fall, this will require engineering and additional funds for equipment adaptation. During the biomass improvement work and training efforts, participation by the operator and local workers was very limited. As much training information as possible was passed on from hands-on work demonstrations, however additional training could have been provided had the operator and workers been present for longer. Mr. Kyler Charlie worked with Mr. Adams for 2- 1/2 days during the first week. Mr. John Walsh (Feb. 4-10) and Mr. Hal Hail (Feb. 6-10) became available and assisted with efforts to finish the boiler tank cleaning to bring the last boiler back on line just before I departed. Community Support Assistance On Jan. 31, Mr. Roberts approached me and requested electrical assistance at the river intake building. He reported that the control panel was not operating the river pump and the water level in the water storage tank (WST) was at about 4 feet. Power was checked through control panel and nominal 230-volt single phase power was available through the starter contactors. I discovered the overload on the 1-1/2 HP motor control box fed from the panel was tripped and continued to trip upon reset. The three-wire control box power fed into a double-throw switch that directs the power to either a well pump inside a casing located in the intake building or to the 230-volt twist outlet outside the building for feeding power to the river pump cord. Resetting and testing amperage draw, I discovered the river pump drawing 43 amps and the well pump Trip Report, Tanana – Biomass Improvements Page 7 Jan. 26-Feb. 11, 2023 drawing 34 amps, far above the max rating of the 11.5-amp max safety rating. Either a short circuit or locked rotor condition was assumed. The river submersible pump (WILO #TWI 4.25-7.10 - P/N# 2711984, Model # FM4301031A, 3 wire, 1 HP , 230 Volt, 8.4 Amp, 3450 RPM, 1 PH) was taken to the WTP to warm up, dry out and be inspected. The motor windings resistance was checked and the motor shaft was not locked and showed no physical resistance when turned by hand. The pump impellers were not clogged. Multiple attempts were made to bump test the pump, but the overload continued to trip. No critical spare pump or splice kits were available for either the river submersible or well submersible pump. It was later discovered that both pumps had quit operating during the la test pumping events. In an attempt to find a solution, we located spare pump wire and replaced the submerged wire section area where nicks and cuts were observed on the insulation hoping it might remedy high amp draw if a short existed. The wire change-out allowed the pump to operate when tested out of water however it still tripped when submerged under load. The Fairbanks remote maintenance worker (RMW) group located and sent a 1-HP two-wire submersible pump, but it didn’t arrive until Feb. 2. The WST water level continued to drop to very low critical level. The operator located a gas-powered fire pump, adapted it, and was able to pump water during the evening of Feb. 1 till the early morning hours, adding to the WST level and keeping the system pressurized. T he two-wire pump from the RMW group was adapted to the existing wiring and was put into operation by the evening of Feb. 2. The urgent event re-enforced the importance of having critical spare pumps on hand at all times. I requested the ANTHC engineering group to locate a vendor to provide a quote for a backup pump, control box and splice kits. I provided that quote to the operator and TTC representatives via text message. I was fortunate to be able to walk through the WTP with Mr. Victor Joseph to review the system, from raw water to treatment to storage and distribution, and pointed out the different improvements ANTHC was involved with since 2020. Two points of concern I shared with Mr. Joseph: 1. The importance of having backup utility operators for the Tanana water and sewer system since Mr. Roberts is expected to start rotational employment with UIC North Slope utilities in the near future. 2. Maintaining critical spare parts on hand for the Tanana water and sewer utility to reduce emergencies like the river pump failure and low WST levels. When asked what items are needed for critical spares, I informed Mr. Joseph most operation and maintenance (O&M) manuals list critical equipment needed. Each system is slightly different and an inventory of parts on hand versus parts needed would require assessment. ANTHC only has a draft copy of the Tanana WTP O&M manual, which doesn’t include a critical spare parts list. Because Tanana is a Village Safe Water (VSW) community, O&M manuals and other records are only available upon request from VSW. A copy of the record WTP constructed design plan set exists in ANTHC’s archives. Trip Report, Tanana – Biomass Improvements Page 8 Jan. 26-Feb. 11, 2023 Of the 17 days spent on travel and work, 2-1/2 days were spent providing community support to repair the river submersible intake pump. T his delayed progress on the biomass system upgrades and training. Thirteen days on-site were dedicated to biomass improvement work and 1-1/2 days were spent on travel from Anchorage. Mr. Adams arrived on-site on Jan. 26 and departed Feb. 2. Mr. Hartvigson arrived on Feb. 6 and departed on Feb. 10. I departed Tanana on Feb. 11 and arrived back in Anchorage later that evening. RECOMMENDATIONS AND/OR CONCLUSIONS: 1. ANTHC to follow up with Tanana utility on biomass operation and needed maintenance items for the utility to procure and stock. 2. Tanana utility should work with the TCC RMW group to assess and develop a utility critical spare parts list to order and stock. Martin Wortman Attachments: Photos cc: James Roberts, Water Plant Operator, Tanana Too’gha Inc. Cliff Wiehl, Too’gha Maintenance Manager, TTC Gladys Erhart, Finance/Administration, TTC Victor Joseph, Executive Director, TCC ec: Lee Meckel, RMW, TCC Noah Tsigonis, RMW Supervisor, TCC Oscar Menendez, Village Safe Water Engineer, Alaska Department of Environmental Conservation DEHE – Brian Menghini/ Valerie Zeedar/ Bailey Gamble/ James Fowler/ Tory Adams/ Kameron Hartvigson Trip Report, Tanana – Biomass Improvements Page 9 Jan. 26-Feb. 11, 2023 PEX Water Supply Line 3/16” Calcium Buildup on Biomass Boiler Hot Vent Piping Trip Report, Tanana – Biomass Improvements Page 10 Jan. 26-Feb. 11, 2023 Cleaning and Vacuuming Biomass Boiler Boiler Hot Vent Piping Scraped and Cleaned Trip Report, Tanana – Biomass Improvements Page 11 Jan. 26-Feb. 11, 2023 Biomass Boiler Y-Strainer Before Maintenance Y-Strainer Removed for Maintenance Trip Report, Tanana – Biomass Improvements Page 12 Jan. 26-Feb. 11, 2023 Cleaning Y-Strainer Screen Y-Strainer Screen After Cleaning Trip Report, Tanana – Biomass Improvements Page 13 Jan. 26-Feb. 11, 2023 Y-Strainer Reinstalled with Gauges Biomass Water Conditioning Filters Trip Report, Tanana – Biomass Improvements Page 14 Jan. 26-Feb. 11, 2023 Old Biomass Boiler Manway Cover New Biomass Manway Cover and Level Sensor Trip Report, Tanana – Biomass Improvements Page 15 Jan. 26-Feb. 11, 2023 Biomass Boiler Heat Exchanger Before Bypass Valve Replacement Biomass Boiler Heat Exchanger After Bypass Valve Replacement Trip Report, Tanana – Biomass Improvements Page 16 Jan. 26-Feb. 11, 2023 Clogged Plates in Biomass Heat Exchanger Replacing Heat Exchanger Plates Trip Report, Tanana – Biomass Improvements Page 17 Jan. 26-Feb. 11, 2023 Original Biomass Intake Air Vent Intake Air Damper Next to Boiler Trip Report, Tanana – Biomass Improvements Page 18 Jan. 26-Feb. 11, 2023 Insulated Box and Direct Vent Biomass Fire Chamber Before Cleaning Trip Report, Tanana – Biomass Improvements Page 19 Jan. 26-Feb. 11, 2023 Biomass Fire Chamber After Cleaning New Biomass Fire Chamber Bricks Installed Trip Report, Tanana – Biomass Improvements Page 20 Jan. 26-Feb. 11, 2023 Biomass Firebox Door with Worn Gasket Worn Biomass Door Latch Handle Trip Report, Tanana – Biomass Improvements Page 21 Jan. 26-Feb. 11, 2023 Worn Biomass Door Hinge Pin Biomass Firebox Door with New Gasket