Very often, gas processing is necessary in order to reduce maintenance costs in the case of highly contaminated fuel gas or to enable exhaust gas treatment with an oxidation catalyst.
A typical biogas processing constellation comprises a gas refrigeration dryer, a compressor, and an active carbon silo. The warm, humid, uncompressed, and roughly desulfurized biogas from the fermenter is converted to cooled, compressed, and thoroughly desulfurized biogas. In most cases, MWM uses oxidation catalysts to comply with the applicable exhaust gas limits. Active carbon desulfurization is applied during the gas processing in order to remove sulfur, which is harmful to the catalyst and to the exhaust gas heat exchanger. As the surface of active carbon is blocked by the humidity of the raw gas, the gas must first be cool-dried. Biogas processing thus closes the gap between the fermenter and the genset/container.
To simplify and accelerate the setup, MWM delivers the gas refrigeration dryer as a complete module to the building site. The active carbon silo used by MWM consists of two chambers and can be operated with break-through protection. Once the working filter is spent, the second filter ensures that the gas is always free of hydrogen sulfide. In this way, the active carbon only needs to be replaced during the next genset maintenance and does not require any additional downtime. The MWM biogas processing is designed for long-term operation and is tuned perfectly to MWM components.