How does the purity of the landfill gas affect how it is used?
Usually in a landfill decomposition process, methane and CO2 are the primary byproducts; about 50% each, or 60% methane and 40% CO2. They form together, they come out of the landfill together, and they can be burned together in an engine or flare. They dont have to be separated to produce power, but some facilities try to make compressed natural gas from landfill gas, so the CO2 has to be separated out to leave a higher concentration of methane. This CO2 can be used as a sellable product, but in most cases its not. Using landfill CO2 in the food industry is probably still a little taboo, but there are other things it can be used for. At facilities that refine the landfill gas for methane it is critical to have low amounts of air in the gas in order to meet the natural gas specification.
