| 摘要 |
An alkylaromatic hydrocarbon is recovered from effluent stream of aromatic hydrocarbon alkylation zone by (a) passing alkylation zone effluent stream which comprises feed aromatic hydrocarbon, prod. alkylaromatic hydrocarbon, and by-prod. alkylaromatic having higher pt. than prod. alkylaromatic hydrocarbon into 1st fractionation column at intermediate pt., with 1st reboiler located at the bottom of 1st fractionation column; (b) supplying heat to 1st fractionation column by vapourising bottoms liq. by indirect heat exchange in 1st reboiler and passing vapour into 1st fractionation column, with vapour having 1st temp.; (c) reccvering 1st net overhead prod. stream, which is rich in the feed aromatic hydrocarbon, from 1st fractionation column; (d) removing 1st net bottoms stream, which is rich in prod. alkylaromatic hydrocarbon, from 1st fractionation column and passing 1st net bottoms stream into 2nd column; (e) removing 2nd net bottoms stream, which is rich in the by-prod. alkylaromatic hydrocarbon, from 2nd fractionation column; (f) supplying additional heat to 1st fractionation column by vapourising process liq. withdrawn at 2nd intermediate point and having a lower average pt. than bottoms liq. entering the 1st reboiler in 2nd reboiler, with the created vapour having a 2nd temp. lower than 1st temp. (g) passing overhead vapour stream, withdrawn from 2nd fractionation column and rich in prod. alkylaromatic hydrocarbon, through 2nd reboiler in indirect heat exchange relationship at 2nd intermediate pt., which results in vapourising process liq. and at least partly condensing 2nd overhead vapour stream and thereby forming a condensate; and (h) withdrawing 1st portion of ondensate as a prod. stream of the process and passing portion of the condensate into 2nd fractionation column as reflux. |
