Patent ID: 7922980

Claim:
In an apparatus for manufacturing styrene by dehydrogenation of ethylbenzene in the presence of steam at elevated temperatures comprising: (a) a reactor system having an inlet and an outlet, and containing a dehydrogenation catalyst, to produce a reactor effluent stream from the reactor system outlet; (b) a fractionation column downstream from the reactor system outlet for processing a first portion of the reactor effluent stream to produce a fractionation overhead stream; (c) a condenser/vaporizer for condensing at least a portion of the fractionation overhead stream by vaporizing ethylbenzene reactor feed; and (d) a conduit for passing the vaporized ethylbenzene reactor feed from the condenser/vaporizer to the reactor system inlet; the improvement comprising: at least a compressor for compressing vapor passing between the fractionation column and the condenser, for compressing vapor passing between the condenser/vaporizer and the reaction system inlet, or both.