Multi-stage gas-entrained liquid separator

Abstract

A multi-stage entrained liquid-gas separator includes a housing divided into upper and lower chambers. The lower chamber is provided with a tangential gas-liquid stream inlet into an annular chamber in which the large entrained liquid drops are centrifugally impinged upon the chamber wall and drained into a lower sump. From the annular inlet chamber the gas-liquid stream is caused to abruptly change direction and flow into a lower-pressure area of the lower chamber for further releasing entrained droplets. From this area the gas-liquid stream is made to flow into an inner chamber provided within the lower chamber and communicating with the upper chamber. A preseparator housed in the inner chamber separates by impingement and coalescence liquid droplets still entrained in the gas-liquid stream and drains the coalesced liquid into an inner sump which in turn drains via a trap into the lower sump. From the preseparator, the gas stream still containing liquid microdroplets is conveyed upwardly into the upper chamber and through a two-stage principal separator in the first, fine upstream stage of which the entrained microdroplets are separated by impingement and coalescence from the gas stream and drained to an upper sump. In the second, downstream coarser stage of the principal separator, separated liquid droplets emerging from the upstream stage are prevented by impingement and drainage from becoming re-entrained in the gas stream discharged to the atmosphere via a gas outlet. An embodiment directed to separating oil from gas turbine bearing sump vent air is disclosed.