UREA SYNTHESIS PROCESS

摘要

An improvement in the cyclic process for producing urea wherein CO2 and NH3 are reacted in the presence of an aqueous ammoniacal solution in a urea synthesis reactor at an elevated temperature and at an elevated pressure in excess of 1800 PSIG to form a urea synthesis reactor effluent fluid at high pressure. The said effluent fluid is split into a minor stream and a major stream. The major stream is let down in pressure and then passed into a gas liquid separator wherein the gas stream rises through a packed midsection into the upper portion of the separator and is then taken off. The minor stream is cooled and then let down in pressure and passed into the upper portion of the gas liquid separator to produce a gas phase which is taken off from the upper portion and a liquid phase which passes down through the packed midsection and contacts the upwardly rising gas phase from the major stream wherein the downwardly passing liquid phase absorbs carbon dioxide and water vapor from said upwardly passing gaseous phase. The said liquid phase enriched in carbon dioxide and water vapor is then taken off from the lower section of the separator and withdrawn together with the liquid phase portion of the major stream. This liquid product is passed to a carbamate decomposer. The gaseous product taken from the upper section of the separator is, after further processing, at least in part recycled to the urea synthesis reactor.