landfill gas management system - michigan state university 485 spring '05/26... · 2005. 4....
TRANSCRIPT
3/31/2004
CE485 1
Landfill Gas Management System
Milind V. Khire, Ph.D., P.E.Department of Civil & Environmental EngineeringMichigan State UniversityA135 Research Complex EngineeringE Lansing, MI 48824(517) 432-3130 [email protected]
Engineered Landfills – Key Components
Final Cap
Surface Water Management System
Gas Collection System
Liner and Leachate Collection System (LCS)
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Landfill Gas Constituents
• CH4
• CO2
• SO2
• H2S• Mercury (Hg)• VOCs• ?
Landfill Gas Regulations
• Explosive Gas Concentration at property boundary shall be < 5%
• Non Methanogenic Organic Compounds (NMOCs) shall be destroyed by 99.9% or more before releasing into the atmosphere
• These regulations only apply to medium or large size landfills
• Small landfills (< 2.5 Million Metric tons total capacity) are exempt from gas collection regulations. However, if neighbors complain about odors, small landfill owners need to collect and manage gas to mitigate odor problems.
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Landfill Gas Management System -Functions
• Collect and Remove Gas from the landfill for treatment and flaring or gas to energy conversion
• Reduces the risk of explosion of landfill• Reduces the risk of ground water and air
pollution from leakage or diffusion of landfill gas
• Odor Control
Essential Components of Landfill Gas Management System
• Vertical Wells or Horizontal Gas Collection Trenches
• Gas Header Pipe• Gas Blower• Condensate Trap• Flare (to burn methane and other non-
methanogenic organic compounds- NMOCs)• Gas to Energy Generator – not essential
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Basic Types of Gas Management Systems
• Passive Venting• Active collection and treatment/flaring
Passive Venting
~MSW ~
Gravel Pack
4 to 6” dia. PVC Conduit
(10 to 14’ high)
Concrete Pad or Seal
• In passive venting, gas is released to the atmosphere without treatment
• Gas comes out its own pressure without the need to apply suction to pull the gas out
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Active Gas Collection – Vertical Wells
~MSW ~Gravel Pack
4 to 6” dia. PVC Conduit
Suction (to blower)
Active Gas Collection – Vertical Wells
~MSW ~
Gravel Pack
4 to 6” dia. PVC Conduit Suction (to
blower)
• In passive venting, gas is collected and treated or flared• Gas comes out under the action of a small amount of
suction applied in the common leachate header pipe.
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Active Gas Collection – Trenches
~MSW ~
4 to 6” dia. PVC Conduit
Suction (to blower)
Landfill Gas Well and Header Pipe
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Landfill Gas Wells and Header Pipe
To Blower
Landfill Gas Well and Header Pipe
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Landfill Gas Manifold
Landfill Gas Condensate Trap
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Landfill Gas Flare
Landfill Gas to Electrical Energy Generator
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Leachate Evaporator Using Gas Energy
Puente Hills Panorama- 4 (middle right)
Note: Greenwaste area, industrial waste tipface, cover stockpile, high standard of cover in general
and odour dispersal fan (middle foreground)
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Puente Hills Panorama– 3 (middle)
Note: LFG pipework and main active face (centre)