A SHELL-AND-TUBE APPARATUS FOR HEAT RECOVERY FROM A HOT PROCESS STREAM

摘要

A shell-and-tube apparatus (1), suitable for use as a waste heat boiler, comprising a vessel with an exchanging section (2) and a separating section (3), wherein: said exchanging section (2) contains a bundle of U-tubes (4) fed with an evaporable liquid medium such as water (W) and exposed to a hot gas (G) flowing in a hot chamber around said tubes, so that said medium is partially evaporated in the tubes while recovering heat from hot gas flowing in the hot chamber (7); said separating section (3) comprises a collection chamber (16) in communication with outlet of the tubes (4) to receive the partially evaporated medium leaving the tubes; said separating section (3) is arranged to provide separation of vapour fraction and liquid fraction from the partially evaporated medium at least partially by gravity; the apparatus also comprises means for controlling the liquid level in the collection chamber and for a partial recycle of the non-evaporated liquid.

主权项

1. A shell-and-tube apparatus comprising a vessel with an exchanging section and a separating section,
wherein: said exchanging section contains a bundle of U-tubes having respective tube inlet ends and tube outlet ends, and a hot chamber around said tubes, said hot chamber being in communication with an input for a hot process stream, said separating section comprises a collection chamber in communication with said outlet ends of tubes, said apparatus also comprises an input for an evaporable liquid medium, which is in communication with said tube inlet ends, so that, during operation, said tubes are exposed to said hot process stream while traversing said hot chamber, and the evaporable medium is heated and at least partially evaporated by flowing inside said tubes, and the at least partially evaporated medium is admitted to said collection chamber after leaving said tubes, said separating section being arranged to provide separation of vapour fraction and liquid fraction from said at least partially evaporated medium.