CENTRIFUGAL STEAM WATER SEPARATOR FOR STEAM GENERATOR

摘要

A centrifugal moisture separator for steam generators is used esp. for natural circulation steam generators of nuclear power plants and comprises a (vertical)cylindrical housing, a vortex chamber tapering conically in the direction of flow inside the housing and an inlet duct at the bottom with blades to impart a twist to the entering steam. The dried steam leaves the top of the housing and water centrifuged inside the vortex chamber is recirculated into the steam generator. The vortex chamber is a perforated venturi tube, comprising a conically tapering inlet portion and a conically diverging diffusor portion continuing as far as the vortex chamber outlet; the centrifuged liquid phase and any solid particles contained in it is pressed through the perforations of the venturi tube into the annular space outside it and inside the housing, and is collected and removed from the bottom of this annular space. Used typically for a pressurised water reactor. The effect of the second, diverging portion of the vortex chamber or separator with perforations in the wall is to ensure that the separated water is projected righ outside the steam flow and therefore cannot be entrained by it again; in the annular space outside the vortex chamber, the water can trickle unimpeded downwards on the outer wall collet at the bottom. Pressure drops are reduced and separation efficiency is increased.