[Simon2440]

I'm interested in the chemistry of biogas production from compostable materials,
Specifically I want to build a small scale anerobic digester to produce primarily methane gas for running in LPG powered cars.
My main question is how to best deal with the impurities within the gas produced. (Carbon dioxide, water vapour and sulphur gas)
Does anyone have experience with scrubbing methods used for cleaning the gas produced?
Thanks in advance