| 摘要 |
The invention relates to a method of separating methane and carbon dioxide from biogas and to a device for carrying out the method. These are intended for purifying biogas, wherein carbon dioxide is separated off from the biogas. Starting from the disadvantages of the known prior art, a method is intended to be provided which is distinguished by an energetically favourable mode of operation. For this the solution proposed is that the biogas is passed under atmospheric pressure and standard temperature into the absorption column, wherein while the biogas ascends through the packed bed, which preferably has a surface area of 600 to 1200 m2/m3 and at a space velocity of 5 to 40 Nm3/m3h, carbon dioxide present in the biogas is bound in the wash liquid by chemosorption. The purified methane gas is taken off at the top of the absorption column at a defined flow velocity. Carbon dioxide bound in the wash liquid is removed by desorption at a relatively high pressure of 2 to 30 bar and a temperature of at least 120°C. Biogas may be separated particularly economically into methane and CO2 by the suggested procedure. |
