It is essential to scrubb out CO2 because of limited fuel storage in bi-fuel car. In burners it is not needed I agree. But how to make it cost effective??
Flow of biogas is only about 120 liters per minute (small farm size digester)and CO2 content is less than 40% (60 to 65% methane). We are using the purified methane gas as vehicle fuel and it means it should be 97% pure methane!
Liquid used for scrubbing is pure water or water with lime stone...
