To tell if your methane is good quality, you need to identify and measure any impurities. Good methane should have a high concentration of methane gas, usually above 50%, and low amounts of unwanted gases like carbon dioxide, hydrogen sulfide, and water vapor.
High levels of impurities can reduce the energy value of the methane and could make it unsuitable to use as fuel. Gas analyzers can measure the composition of the methane produced in your waste lagoon or capture system. If the gas has too many impurities, it may need cleaning or upgrading before use. Once purified, the methane should burn cleanly without producing excessive smoke or smells.
