Gas Separator Assembly For Generating Artificial Sump Inside Well Casing

Abstract

A gas separator assembly generates an artificial sump in a production casing receiving a production tubing string with a downhole pump at the bottom end thereof. The assembly includes an inner casing in series with the production casing of the well and an outer casing supported externally of the inner casing. First and second ports at opposing top and bottom ends of the outer casing communicate from a primary passage in the inner casing to a secondary passage between the inner and outer casings. A barrier supported in the primary passage between the first and second ports diverts flow through the secondary passage and effectively defines the sump area in the primary passage between an inlet of the downhole pump adjacent the barrier and the first port thereabove.

1 - 20 . (canceled) 
     
     
         21 . An assembly, comprising:
 a first well casing;   a pipe disposed within the first well casing;   a pump in fluid communication with the pipe, the pipe having a distal inlet;   a containment structure disposed about the distal inlet; and   a first port disposed on the containment structure;   wherein the assembly defines a fluid flow path, wherein a combined fluid stream is separated into a heavy fluid stream and a light fluid stream at the first port, the heavy fluid stream extending through the first port into the containment structure and into the distal inlet, the light fluid stream extending generally upwardly in an annular space within the well casing around the pipe.   
     
     
         22 . The assembly of  claim 21  wherein the containment structure defines a sump area between the first port and the distal inlet of the pipe. 
     
     
         23 . The assembly of  claim 21  in which the containment structure comprises a barrier to prevent the combined fluid stream from entering the containment structure from other than the first port. 
     
     
         24 . The assembly of  claim 23  in which the containment member is configured for connection to a well casing. 
     
     
         25 . The assembly of  claim 21  further comprising a second port formed in the containment member below the distal inlet. 
     
     
         26 . The assembly of  claim 25  in which a barrier is formed between the second port and the pump inlet. 
     
     
         27 . The assembly of  claim 26  in which the fluid flow path extends from the containment member, out the second port into an annular space around the containment member, to the first port. 
     
     
         28 . The assembly of  claim 21  in which the fluid flow path extends from an annular space around the containment member to the first port. 
     
     
         29 . The assembly of  claim 21  in which the heavy fluid stream is substantially only liquid. 
     
     
         30 . The assembly of  claim 21  in which gas within the combined fluid stream primarily enters the light fluid stream when the fluid flow path passes the first port. 
     
     
         31 . The assembly of  claim 21  wherein the containment structure is situated within an expanded well casing section having a greater diameter than the first well casing. 
     
     
         32 . The assembly of  claim 31  wherein the diameter of the first well casing is approximately 5.5 inches and wherein the diameter of the expanded well casing section is 7 inches. 
     
     
         33 . The assembly of  claim 21  wherein the inner diameter of the containment structure is substantially identical to the inner diameter of the first well casing. 
     
     
         34 . The assembly of  claim 21  in which a plurality of first ports are spaced about the containment structure. 
     
     
         35 . The assembly of  claim 21  further comprising a sleeve moveable between a position to close the first port and a position to open the first port. 
     
     
         36 . The assembly of  claim 21  in which the pump is an electrical submersible pump or a reciprocating rod pump. 
     
     
         37 . The assembly of  claim 21  in which the pump is disposed within the pipe. 
     
     
         38 . A method of separating gas from a combined fluid stream being produced in a well, the method comprising:
 providing a barrier to direct combined fluid into an annular space formed about a containment structure;   providing a production tubing string in fluid communication with a pump, the pump displacing fluid at a pump inlet disposed within the containment structure; and   separating the combined fluid into a gas-rich stream and a gas-poor stream at a first port of the containment structure such that the gas poor stream extends through the containment structure to the pump inlet and the gas-rich stream extends within an annular space around the production tubing string.   
     
     
         39 . The method of  claim 38  in which the combined fluid stream flows through an expanded casing region, the expanded casing region having an outer diameter greater than the outer diameter of a primary casing region. 
     
     
         40 . The method of  claim 38  comprising creating an artificial sump within the containment structure between the first port and the pump inlet.