Methods and Assemblies for Separating Liquid from a Gas-Liquid Stream

Abstract

A two stage gas-liquid separator assembly includes a housing having an inlet for receiving a gas-liquid stream and an outlet for discharging a gas stream. A first plenum chamber includes a pre-separator that causes liquid to separate from the gas-liquid stream and to drain to a lower portion of the first plenum chamber. A second plenum chamber includes a main separator downstream of the pre-separator that further causes liquid to separate from the gas-liquid stream and to drain to a lower portion of the second plenum chamber. A first drain port drains liquid from the lower portion of the first plenum chamber and a second drain port drains liquid from the lower portion of the second plenum chamber. Liquid drains from the first and second plenum chambers regardless of a pressure difference between a pressure in the first plenum chamber and a pressure in the second plenum chamber.

What is claimed is: 
     
         1 . A two-stage gas-liquid separator assembly comprising:
 a housing haying a flowpath therethrough from upstream to downstream, the housing having an inlet, for receiving a gas-liquid stream and an outlet fur discharging a gas stream;   a first plenum chamber defined by the housing and comprising a pre-separator that causes liquid to separate from the gas-liquid stream and to drain to a lower portion of the first plenum chamber;   a second plenum chamber defined by the housing and comprising a main separator downstream of the pre-separator that further causes liquid to separate from the gas-liquid stream and to drain to a lower portion of the second plenum chamber;   a first drain port in the housing draining liquid from the lower portion of the first plenum chamber; and   a second drain pot in the housing draining liquid from the lower portion of the second plenum chamber;   wherein liquid drains from the lower portions of the first and second plenum chambers through the first and second drain ports, respectively, regardless of a pressure difference between a pressure in the first plenum chamber and a pressure in the second plenum chamber.   
     
     
         2 . The assembly of  claim 1 , further comprising a conduit in fluid communication with both the first and second drain ports that conveys liquid from the lower portions of the first and second plenum chambers away from the housing. 
     
     
         3 . The assembly of  claim 2 , wherein the conduit comprises a pump that removes liquid from the lower portions of the first and second plenum chambers through the first and second drain ports, respectively. 
     
     
         4 . The assembly of  claim 3 , wherein the pump comprises a jet pump in fluid communication with both the first and second drain ports. 
     
     
         5 . The assembly of  claim 4 , wherein the jet pump comprises a first jet orifice accelerating pressurized fluid so as to pump liquid from the first drain port and a second jet orifice accelerating pressurized fluid so as to pump liquid from the second drain port. 
     
     
         6 . The assembly of  claim 5 , wherein the pressurized fluid is oil. 
     
     
         7 . The assembly of  claim 5 , wherein the jet pump comprises a feed bore that supplies the pressurized fluid to both the first and second jet orifices. 
     
     
         8 . The assembly of  claim 7 , wherein the jet pump comprises a first suction port that receives liquid from the first drain port and pressurized fluid from the first jet orifice, and a second suction port that receives liquid from the second drain port and pressurized fluid from the second jet orifice. 
     
     
         9 . The assembly of  claim 8 , wherein the jet pump comprises a mixing bore that receives liquid from both the first suction port and the second suction port. 
     
     
         10 . The assembly of  claim 4 , wherein the jet pump is coupled to the housing. 
     
     
         11 . The assembly of  claim 10 , wherein the second drain port comprises a tube extending from the lower portion of the second plenum chamber through the first plenum chamber to the jet pump. 
     
     
         12 . The assembly of  claim 1  further comprising a chimney supported by the housing and extending from the first plenum chamber into the second plenum chamber and allowing for the gas-liquid stream to flow therethrough. 
     
     
         13 . The assembly of  claim 12 , wherein the lower portion of the second plenum chamber comprises a funnel that slopes downwardly from an inner surface of the housing to an external wall of the chimney so as to drain liquid to the second drain port. 
     
     
         14 . The assembly of  claim 12 , wherein the main separator is an impactor separator comprising a nozzle plate coupled to a downstream end of the chimney and haying a plurality of nozzles therethrough that accelerate the gas-liquid stream toward an impaction plate downstream of the nozzle plate. 
     
     
         15 . The assembly of  claim 14 , further comprising a shroud extending circumferentially and downwardly from the impaction plate and surrounding at least the downstream end of the chimney. 
     
     
         16 . The assembly of  claim 12 , wherein the main separator is a coalescer separator comprising a filter media coupled to a downstream end of the chimney. 
     
     
         17 . The assembly of claim I wherein the pre-separator is a cyclone separator. 
     
     
         18 . The assembly of  claim 17 , further comprising an arched baffle adjacent the inlet that guides the gas-liquid stream along an inner surface of the first plenum chamber as the gas-liquid stream enters the first plenum chamber. 
     
     
         19 . A method for separating liquid from a gas-liquid stream, the method comprising:
 introducing the gas-liquid stream into a housing having a flowpath therethrough from upstream to downstream;   separating, liquid from the gas-liquid stream in a first plenum chamber defined by the housing;   draining liquid to a lower portion of the first plenum chamber and through a first drain port;   further separating liquid from the gas-liquid stream in a second plenum chamber defined by the housing and downstream of the first plenum chamber;   draining liquid to a lower portion of the second plenum chamber and through a second drain port; and   pumping liquid from the lower portions of the first and second plenum chambers through the first and second drain ports, respectively.   
     
     
         20 . The method of  claim 19 , further comprising pumping liquid from the first and second drain ports into first and second suction ports, respectively. 
     
     
         21 . The method of  claim 20 , further comprising accelerating pressurized fluid through first and second jet orifices and into the first and second suction ports, respectively, so as to pump liquid from the lower portions of the first and second plenum chambers, respectively. 
     
     
         22 . The method of  claim 21 , further comprising supplying the pressurized fluid to the first and second jet orifices from a common pressurized fluid source. 
     
     
         23 . The method of  claim 22 , further comprising mixing the pressurized fluid from the first jet orifice and the liquid from the first drain port with the pressurized fluid from the second jet orifice and the liquid horn the second drain port in a common mixing chamber. 
     
     
         24 . The assembly of  claim 21 , wherein the pressurized fluid is oil. 
     
     
         25 . The assembly of  claim 24 , wherein the oil is provided from an oil pump coupled to a crankcase of an engine. 
     
     
         26 . The assembly of  claim 21 , wherein the pressurized, fluid is air. 
     
     
         27 . The assembly of  claim 26 , wherein the air is provided from a turbocharger. 
     
     
         28 . An assembly for removing scavenged liquid from a two-stage gas-liquid separator, the assembly comprising:
 a first suction port receiving scavenged liquid from a first stage of the gas-liquid separator;   a second suction port receiving scavenged liquid from a second stage of the gas-liquid separator;   a first jet orifice accelerating a pressurized fluid into the first suction port;   a second jet orifice accelerating the pressurized fluid into the second suction port;   a feed bore supplying both the first and second jet orifices with the pressurized fluid, and   a common mixing bore receiving the pressurized fluid from the first and second jet orifices and receiving scavenged liquid from the first and second stages of the gas-liquid separator.   
     
     
         29 . The assembly of  claim 28 , further comprising a first connection port conveying liquid from an outlet in the first stage of the gas-liquid separator to the first suction port, and a second connection port conveying liquid from an outlet in the second stage of the gas-liquid separator to the second suction port. 
     
     
         30 . The assembly of  claim 28 , wherein the first and second suction ports extend perpendicularly to a flow of the accelerated, pressurized fluid from the first and second jet orifices, respectively. 
     
     
         31 . The assembly of  claim 28 , further comprising a drain line coupled to the common mixing bore that drains the scavenged liquid from the common mixing bore to a crankcase of an engine. 
     
     
         32 . The assembly of  claim 28 , wherein the pressurized fluid is oil. 
     
     
         33 . The assembly of  claim 28 , wherein the pressurized fluid is air. 
     
     
         34 . The assembly of  claim 28 , wherein the assembly is integrally molded to a lower portion of a housing of the gas-liquid separator. 
     
     
         35 . The assembly of  claim 28 , wherein the assembly is bolted to a lower portion of a housing of the gas-liquid separator.