| 摘要 |
PURPOSE:To reduce the amount of product gas to be used as washing gas and to obtain the product gas with improved purity by installing a vertical pressure equalizing process, in which gas containing impurities in the gas staying upper and lower parts of an adsorption tower is transferred to an adsorption tower after a desorption process, between an adsorption process and a washing process. CONSTITUTION:Raw gas is introduced into an adsorption tower A by opening upper and lower automatic valves 1A, 5A of the tower A to start an adsorption process. After the adsorption process, a gas with the same composition as the raw gas exists in the upper gas staying part 17 of the tower A, while a gas with the same composition as adsorbed offgas exists in the lower gas staying part 18 of the tower A. Then, valves 8A, 8D, 9A, 9D are opened to connect the adsorption tower A with an adsorption tower D which is in a vacuum state after a desorption process. Impure gas deposited in the parts 17, 18 is transferred to prepare a washing process in which product gas is used. |
