Landfill-gas extraction systems apply negative pressure (vacuum) to extraction wells, facilitating the active removal of contaminated vapors from solid-waste landfill sites. This vapor stream is typically separated into liquid and vapor, which are then treated separately.
Negative pressure is created in the extraction wells by a vacuum blower installed in the treatment system. Contaminated vapors from extraction wells are combined into one stream, usually at the treatment system, using a manifold. A vapor/liquid separator then separates the majority of the entrained liquid. The liquid stream is held in the vapor/liquid separator and discharged or treated as required, while the landfill gas stream is extracted by the vacuum blower. The landfill gas can then be discharged to atmosphere, combusted in an enclosed flare, or used for energy generation.
Considerations in the design of a landfill gas extraction system include: the number of extraction wells, required air flow rate, required vacuum, expected liquid flow rate, levels of contaminants, and discharge requirements. Various types and sizes of vacuum pumps are available, as are a number of flaring options.
Please follow the links to view the various types of equipment used in landfill gas extraction systems.
