Combustible gas prodn. - from fermentation gas by compression and selective dissolution leaving high methane gas

摘要

Prodn. of combustible gas by fermentation of organic substances is based on compressing the fermentation gas which consists of methane and carbon dioxide, and removing at least a part of the carbon dioxide. During the compression the fermentation gas is contacted with a liquid which dissolves carbon dioxide to a greater extent than methane. This pressurised mixt. is sepd to yield combustible gas with a higher methane content and a liquid with the dissolved fermentation gas percentage, from which most of the gas is then extracted. The degassed liquid is recycled to be contacted with the fermentation gas. This reduces to a min. the engineering effort for the redn. of the carbon dioxide percentage in the combustible gas, and produces a fuel gas of higher calorific value.