Landfill Energy Resource

Methane Collection System

Extracting methane from a landfill is accomplished by drilling wells and extracting the gas through a piping system with 'pull' provided by a motor-driven blower. Wells are drilled into the landfill at a rate of about 1 per acre. Each wellhole goes about 3/4 towards the bottom of the landfill, and contains a slotted HDPE pipe. Gravel, tire pieces, or a similar material is used to backfill the hole creating a barrier between the well-pipe and the edge of the waste. Both waste and water must be prevented from entering the well-pipe.

Each well-pipe is attached to a ground-top pipe that transports the gas to a central location. Wells typically have an above-ground extension that contains manual adjustment to affect the gas flow rate and 'pull' pressure, and are also compatible with gas testing equipment that measures not only flow rates, but also methane content.

The pipes transporting the gas from each well join together at the central station. Gas is pulled from the wells using pressure provided by the blower. Once reaching the central station the gas is either burned of in a flare or prepared for its end-use by cleaning impurities, scrubbin carbon dioxide, or pressurization.