Patent ID: 6929680

Claim:
A process for landfill gas treatment and separation of methane gas and carbon dioxide gas contained therein, and for producing natural gas, carbon dioxide, and regenerating a carbon dioxide absorption material, comprising the steps of: flowing landfill methane gas from wells to a collector, conducting the gas from the collector to a first separator and separating any heavier liquids and solids in the gas flowing into the first separator; compressing the gas from the first separator and conducting it to an absorber having an absorbent therein; mixing the gas and an absorbent to produce carbon dioxide saturated absorbent and purified methane gas containing little carbon dioxide; separating much of the carbon dioxide and methane gas from the carbon dioxide saturated absorbent in a second separator; removing any excess water vapor from the purified methane gas in one of two alternate dehumidifying absorbers with an adsorbent; regenerating the adsorbent in either of the two dehumidifying absorbers by supplying gas from the second separator; conducting the gas used to regenerate the adsorbent from the dehumidifying absorber to the first separator; switching between regenerating the adsorbent and dehumidifying the purified methane gas; and regenerating the carbon dioxide saturated absorbent.