Abstract: The invention is directed to processes and apparatuses for gas treatment, in particular for the purification of methane rich gas streams, such as gas obtained from the conversion from organic matter (“biogas”). In accordance with the present invention there is provided an apparatus and a process for producing a purified methane comprising gas stream (P) from a methane containing gas stream (A), comprising the steps of: (a) pressurising said methane containing gas stream (A) and subsequently cooling it, whereby a stream comprising condensed contaminants (C) and a methane comprising stream (B) are obtained; (b) optionally feeding said methane comprising stream (B) to an adsorption unit and/or a catalytic conversion unit, whereby the concentration of contaminants in stream (B) is further decreased; and (c) cooling the methane comprising stream (B) to a temperature which is sufficient to condensate CO2 from said stream (B), whereby said purified methane comprising gas stream (P) is obtained.