| abstract |
The invention relates to a method for separating reaction products of methanol dehydration to prepare dimethyl ether. The reaction product from a methanol dehydration reactor is cooled and enters a gas-liquid separation tank, and the liquid phase material enters a dimethyl ether purification tower. There are topping section, refining section, washing and removing impurity section and stripping section to the bottom, and the solution containing ethanol and ester impurities is extracted from the side line of washing and impurity removing section and sent to the ethanol refining unit; The flash gas from the gas-liquid separation tank and the purge gas from the carbonylation unit are combined into the tail gas scrubbing tower. After washing with the alcohol aqueous solution in the lower section and the washing water in the upper section, the tail gas after removing oxygenates can be sent to the PSA unit for recovery of synthesis gas. Compared with the prior art, the present invention solves the problem of the accumulation of impurities in the system brought by the raw material methanol and the problem of recovering the organic matter in the tail gas to make it meet the downstream PSA treatment requirements, which is beneficial to reduce energy consumption, reduce material loss, reduce reactor, precision Distillation tower and other related equipment piping material requirements and dimensions, saving investment. |