PROCESS FOR PRODUCING OLEFINS

摘要

A process for producing olefins comprises providing a vapor product stream from an oxygenate to olefin reaction, the vapor product stream comprising C₂ to C₄ olefins, C₂ to C₆ carbonyl compounds and water. The vapor product stream is cooled to provide a first vapor effluent stream comprising no more than 10 wt. % water, and a liquid water-rich stream. The first vapor effluent stream, and a first wash flash vapor stream, are compressed from a first pressure to a second pressure greater than said first pressure to form a second vapor effluent stream, which is then cooled to form a cooled second effluent stream that is at least partially in the vapor state. At least part of the cooled second effluent stream is washed with a liquid alcohol-containing stream, at a third pressure greater than the first pressure but not greater than the second pressure, to produce a wash liquid stream, which comprises C₃ and C₄ olefins, and a wash vapor stream, which contains less C₂ to C₆ carbonyl compounds than the first vapor effluent stream. The wash liquid stream is exposed to a pressure of at least the first pressure but less than the third pressure to form a first wash flash liquid stream and the first wash flash vapor stream, the first wash flash vapor stream being provided for compression with the first vapor effluent stream.