Apparatus for removing carbon dioxide gas and moisture from methane-rich gas mixture.

摘要

This invention relates to the improvement of the so-called PSA method, and more particularly to an apparatus for removing inert gases such as CO2 gas, moisture and the like, and recovering active gases such as H2, CH4 and the like as useful fuel gases for city gas with the utmost effciency, which are commonly produced during the intermediate process of city gas production on SNG basis in using the PSA method. The present inventive system comprises four adsorption column units (A)(B)(C)(D), each of which is used in sequence cyclically under the rotation including an adsorption process, a super-adsorption process with a rinsing step, a desorption process with a series of depressurization steps by suction, and a pressurization process by means of a carbon type adsorbent filled within the columns. The recovered gases obtained in the desorbed gases are recycled into a crude gas feeding pipe line (a), as these still contain a combustible component such as H2, CH4 and the like which require further refinement repeatedly without any gas pressure fluctuation because of the employment of a water-sealed gas holder (12) positioned between a desorbed gas pipe line (g) and a recovered gas pipe line (f).