| 摘要 |
The invention relates to a device for separating a gas mixture into a product gas and an offgas by gas permeation, having a membrane unit (1) and a compressor (3) that is connected upstream of the membrane unit (1) and is preferably adjustable in terms of rotational speed, which membrane unit (1) has a gas inlet (1a), an outlet (1b) for retentate or product gas, and an outlet (1c) for permeate or offgas, wherein the membrane unit (1) has at least one other permeate outlet (1c') that is downstream of the gas inlet (1a), and the permeate outlet (1c') of the membrane unit (1) is connected by lines on the suction side to the compressor (3) or to the gas supply leading into the compressor, and wherein a pressure-regulating device (2) is provided at or downstream of the retentate outlet (1b), and use is made of a gas mixture, consisting primarily of CH4/CO2 and having a methane concentration of not greater than 30% by volume; and to the use of such a device and to a corresponding method. |
