摘要 |
<p>A method for separating methane and carbon dioxide from biogas and a device are intended for purifying biogas, wherein carbon dioxide is separated off from the biogas. The method is distinguished by an energetically favorable mode of operation. The biogas is passed under atmospheric pressure and standard temperature into an absorption column. While the biogas ascends through a packed bed, which 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 a 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 into methane and CO2.</p> |