SWANA Chapter Conference 2008 West Edmonton Landfill Leachate Treatment Plant By Steve Johnson M.Eng, P.Eng

Introduction Leachate Management Options West Edmonton Leachate treatment process Treatment Plant Commissioning/Status Lessons learned

Leachate Management Options Dispose to municipal wastewater treatment plant Dispose to deepwell recirculate Onsite treatment Mechanical plant Evaporator wetlands Do nothing

Leachate treatment process Phases of leachate management since 1974 Do nothing dust control Recirculation/offsite deep well disposal Develop leachate treatment plant

Leachate treatment process In 2006 evaluate leachate treatment options Consultants Leachate quantity estimate Technology evaluation Disposal options Haul to deepwell – unreliable Recirculation no longer approved by AENV City of Edmonton sewer bylaw To reduce liability best to treat on-site

Treatment Plant Commissioning/Status New Logic Research Inc. Vibratory Sheer Enhanced Processing technology Leachate pilot plant test conducted in US Pilot test basis 5 day trial Several membranes investigated for pressures, short term line out, concentration, cleaning

Treatment Plant Commissioning/Status

Treatment Plant Commissioning/Status

Plant set up during fall of Feed tanks 3 mix tanks 2 concentrate tanks 2 permeate tanks Hot water tank VSEP skid Pumps, valves, hoses Treatment R&D trials for approximately 6 months Leachate mixes as quality varies throughout landfill Single pass and percent recovery modes pH, anti-scaling, and process temperature

Treatment Plant Commissioning/Status Quality targets Permeate - City of Edmonton sanitary sewer bylaw Permeate - Agriculture irrigation guideline Concentrate - Non-haz waste – AB User’s Guide Operational finding with current leachate mix Single pass mode 4 to 4.5 m3/hr depending on cleaning frequency Permeate to concentrate ratio of 80:20

Treatment Plant Commissioning/Status Operational finding with current leachate mix (cont.) Percent recovery mode Membrane efficiency decreases at a faster rate then single pass Concentrate quality worse then single pass Current Operation Six hours per day five days per week Two hours per day for cleaning

Treatment Plant Commissioning/Status Future developments R&D to trial temperature adjustment (heat exchanger), pH adjustment, and anti-scaling to determine affect on membrane performance Plan to add another shift in route to automate plant for 24 hr/d operation To include additional feed, blend, and concentrate tanks Treatment target of 6 to 7 m3/hr

Lessons learned New computer hard drives can crash (have a back-up) There is always one or more parameters where mass balance doesn’t apply to the laboratory results between feed, concentrate and permeate New Logic Research has good customer service and documentation (process binders, operations binders) Plant design to include upgraded breaker and checkvalve in cleaning loop Laboratory response time is inadequate for R&D Limited odour experienced R&D takes much longer than anticipated

Questions