1 / 42

On-Site Leachate Management RM of Tache Pilot Study

On-Site Leachate Management RM of Tache Pilot Study. Leachate. Any liquid that is in contact with refuse Waste will absorb moisture up to its field capacity. Beyond this point, any additional moisture will contribute to leachate ( not account ing for channelling ). Quantity of Leachate.

Télécharger la présentation

On-Site Leachate Management RM of Tache Pilot Study

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. On-Site Leachate Management RM of Tache Pilot Study

  2. Leachate • Any liquid that is in contact with refuse • Waste will absorb moisture up to its field capacity. Beyond this point, any additional moisture will contribute to leachate (not accounting for channelling).

  3. Quantity of Leachate Function of: • Landfill size (footprint) • Water Balance (precip, evap) • Runoff/surface water shedding • Water content of incoming waste • Incoming waste typ 20% moisture • Field Capacity typ 55% moisture

  4. Leachate Minimization • Why?… • Implications of handling • Treatment costs • Disposal issues

  5. Leachate • We can influence the amount we generate,but • We can’t ‘stop the flow’

  6. Operations to Minimize Leachate Generation • Minimize active face area • Cover daily • Grade intermediate slopes to shed water

  7. Leachate Management • Through design and operations, the objective is to minimize leachate • What can we do with the leachate we do generate?

  8. Leachate • Currently allowed in MB: • Spectre of no treatment permitted in MWWTP • No recirculation • Not acceptable to exfiltrate from base of landfill • No purpose made leachate treatment facility in MB

  9. Leachate • So what do we need to have happen?

  10. Leachate • The Province can’t write a law that prohibits landfills from generating leachate so • We need to create options for leachate treatment/management

  11. Leachate Management • On site storage (tank, pond, sump) • Off site treatment (WTP) • On site management • bioreactor • evaporation pond • on site treatment plant

  12. Leachate Management • off site • transportation costs and risk • treatment cost • sludge and effluent disposal • on site --- desireable

  13. On site Treatment • For practical/ cost reasons this is rarely selected • Complexity of operation • Availability of Municipal wastewater treatment plant capacity

  14. Problems with using Municipal plants • Allocation of available municipal treatment plant capacity to high strength leachate • Limitations of loading rates to plants • Loss of municipal plant capacity for conventional community growth

  15. Leachate • In the interim, what do landfill operators do? • Ones that own MWWTPs still use that option ( sunsetting) • Ones that don’t have MWWTPs?? [ie. municipalities and private]

  16. Typical Leachate Treatment in Manitoba • Trucked to MWWTP ( sunsetting) • No removal from landfill • On site holding • Other?? Unreported action

  17. Here’s an option • Overview of Pilot Study of Evaporation Pond and Treatment in the RM of Tache • Description of Operations • Operating Parameters • Summary of Pilot Study 7 Years of operation • Quantity • Quality • Observations

  18. On Site Leachate Volume Reduction • Use the net water deficit opportunities • Mid west region application

  19. RM of Tache • Pilot study began in 2002, under the authority granted by MBC. • Primary function of the evaporation pond; - reduce the quantity of leachate to be treated, and, - to improve the quality for ultimate discharge. • Leachate from waste cells is pumped to evaporation pond. • Evaporation pond equipped with spray nozzles to evaporate the liquid.

  20. RM of Taché Leachate Evaporation Pond Pilot Project • Design considerations • Spray nozzle design • Wind drift • Pond depth • Odour migration

  21. Water Balance • June thru Sept net water deficit: Winnipeg / Steinbach records • June 68.8 mm • July 89.8 mm • August 71.8 mm • Sept 43.9 mm

  22. Waste Cell Evaporation Pond Retention Pond Waste Cell Site Plan

  23. Operation Goals • On-site responsibility for leachate management; • Optimize leachate volume reduction; • Elimination of chemicals addition for treatment of leachate or hauling to WWTP; • Acceleration of leachate stabilization. • Pretreatment of leachate on-site to reduce biological load; • Minimize long-term liability.

  24. Evaporation Pond

  25. Nozzles and Water Droplet Design Spray Nozzle Spray Pattern

  26. Spray Nozzles Level Gauge Stick Evaporation Pond

  27. Spray nozzle

  28. Evaporation Pond

  29. Description of Operations • Operational monitoring requirements includes recording: • Precipitation, wind speed, ambient temperature, • Daily time (duration) of aeration pump operation and pond gauge reading, • Data collecting: physical – chemical analysis, • Volume of transferred liquid from EP to Retention Pond at the end of operation seasons.

  30. Operating Parameters • On average 100 kPa (15 psi) in the sprayer/by-pass circuit with leachate spraying (< 1m high), permit continuous operation of the EP • If, with the “by-pass” opened, the spray from the evaporation pond drifts beyond the top of the berm, the sprayer pump shall be turned off. • Hours of operation of the sprayer system will be recorded on the “Leachate Pond Operating Record”, which is maintained by landfill operators

  31. Monthly Volume of Liquid Processing in Evaporation Pond

  32. Summary of 2008 Pilot Study Quantity

  33. Quantity of liquid processing in Evaporation Pond (2002 - 2008 Year)

  34. BOD and TOC over time in Evaporation Pond for 2008

  35. Observations • For 2008 Pilot Study, 2,130 m3 of liquid was managed in the evaporation pond and 1,470 m3 of liquid was evaporated (9.5 m3/day) • Organic content expressed as BOD and TOC were reduced in the operation of the spray evaporation pond.

  36. Summary of Pilot Study - Quality • The spraying/evaporation process is enabling significant biological stabilization of organic content. • This is considered to be due to anaerobic stabilization of organics, as the leachate resides in the landfill waste mass, prior to extraction. • Dissolved metals are precipitating as metal sulphides as pH is adjusted ‘up’ in the spray pond.

  37. Pilot Study- Design Parameter Development • Typical leachate generation rates; 200 to 500 cu m/ha/yr • Tache 600 cu m/ha/yr • Total evaporation achieved 6 cu m/1000m2 evap pond/day • Using 100 operating days, evaporation pond sizing 1 ha evap pond per 10 ha landfill

  38. Go Forward Challenges • End of operating season • Off site haul for treatment? • Where to? • Quality for surface discharge? • Return to Landfill • Is return flow recirculation? • Current attitude of regulator • Options for Operators/Owners

More Related