Downhole gas separator

Abstract

A gas separator including a first separator section and a second separator section. The first separator section and the second separator section each including an outer tubular member having at least one opening extending therethrough adjacent an upper end and an inner tubular member positioned in the outer tubular member to define an annulus. The annulus of the first separator section is fluidically sealed from a tubing string. A lower end of the inner tubular member of the second separator section is open to define a lower open end having a flow area and the lower end of the outer tubular member is fluidically sealed. The inner tubular member of the first separator section has at least one opening extending therethrough adjacent the lower end thereof. The opening has a flow area less than the flow area of the lower open end.

What is claimed is: 
     
         1 . A gas separator, comprising:
 a first separator section, comprising:
 a first outer tubular member having an upper end, a lower end, and a sidewall extending between the upper end and the lower end, the sidewall having at least one opening extending therethrough adjacent the upper end, the upper end of the first outer tubular member connectable to a lower end of a tubing string positionable in a wellbore; and 
 a first inner tubular member having an upper end, a lower end, and a sidewall extending between the upper end and the lower end, the first inner tubular member positioned in the first outer tubular member to define a first annulus between the first outer tubular member and the first inner tubular member, the upper end of the first inner tubular member connected to the upper end of the first outer tubular member so the first annulus is fluidically sealed from the tubing string and the first inner tubular member is in fluid communication with the tubing string when the first inner tubular member is connected to the tubing string, the lower end of the first inner tubular member connected to the lower end of the second outer tubular member; and 
   a second separator section, comprising:
 a second outer tubular member having an upper end, a lower end, and a sidewall extending between the upper end and the lower end, the sidewall having at least one opening extending therethrough adjacent the upper end, the upper end of the second outer tubular member connected to the lower end of the first outer tubular member, the lower end of the second outer tubular member being fluidically sealed; and 
 a second inner tubular member having an upper end, a lower end, and a sidewall extending between the upper end and the lower end, the second inner tubular member positioned in the second outer tubular member to define a second annulus between the second outer tubular member and the second inner tubular member, the upper end of the second inner tubular member connected to the lower end of the first inner tubular member so the second annulus is fluidically sealed from the first annulus and the second inner tubular member is in fluid communication with the first inner tubular member, the lower end of the second inner tubular member being open to define a lower open end having a flow area, 
 wherein the sidewall of the first inner tubular member has at least one opening extending therethrough adjacent the lower end thereof, the opening having a flow area less than the flow area of the lower open end. 
   
     
     
         2 . The gas separator of  claim 1 , wherein the opening of the first outer tubular member has a flow area, and wherein the flow area of the opening of the first inner tubular member is less than the flow area of the opening of the first outer tubular member. 
     
     
         3 . The gas separator of  claim 1 , further comprising a screen positioned across the opening of the first inner tubular member. 
     
     
         4 . A gas separator, comprising:
 a tubing string positioned in a wellbore, the tubing string having an upper end and a lower end;   a first separator section, comprising:
 a first outer tubular member having an upper end, a lower end, and a sidewall extending between the upper end and the lower end, the sidewall having at least one opening extending therethrough adjacent the upper end, the upper end of the first outer tubular member connected to the lower end of a tubing string; and 
 a first inner tubular member having an upper end, a lower end, and a sidewall extending between the upper end and the lower end, the first inner tubular member positioned in the first outer tubular member to define a first annulus between the first outer tubular member and the first inner tubular member, the upper end of the first inner tubular member connected to the upper end of the first outer tubular member so the first annulus is fluidically sealed from the tubing string and the first inner tubular member is in fluid communication with the tubing string when the first inner tubular member is connected to the tubing string, the lower end of the first inner tubular member connected to the lower end of the second outer tubular member; and 
   a second separator section, comprising:
 a second outer tubular member having an upper end, a lower end, and a sidewall extending between the upper end and the lower end, the sidewall having at least one opening extending therethrough adjacent the upper end, the upper end of the second outer tubular member connected to the lower end of the first outer tubular member, the lower end of the second outer tubular member being fluidically sealed; and 
 a second inner tubular member having an upper end, a lower end, and a sidewall extending between the upper end and the lower end, the second inner tubular member positioned in the second outer tubular member to define a second annulus between the second outer tubular member and the second inner tubular member, the upper end of the second inner tubular member connected to the lower end of the first inner tubular member so the second annulus is fluidically sealed from the first annulus and the second inner tubular member is in fluid communication with the first inner tubular member, the lower end of the second inner tubular member being open to define a lower open end having a flow area, 
 wherein the sidewall of the first inner tubular member has at least one opening extending therethrough adjacent the lower end thereof, the opening having a flow area less than the flow area of the lower open end. 
   
     
     
         5 . The gas separator of  claim 4 , wherein the opening of the first outer tubular member has a flow area, and wherein the flow area of the opening of the first inner tubular member is less than the flow area of the opening of the first outer tubular member. 
     
     
         6 . The gas separator of  claim 4 , further comprising a screen positioned across the opening of the first inner tubular member. 
     
     
         7 . The gas separator of  claim 4 , wherein the tubing string includes a pump assembly positioned uphole of the first separator section. 
     
     
         8 . The gas separator of  claim 7 , wherein the pump assembly comprises:
 a pump barrel having an upper end, a lower end, and a chamber extending through the pump barrel from the upper end to the lower end, the chamber being in fluid communication with the first separator section;   a standing valve located in the pump barrel to permit one way flow of fluid into the chamber of the pump barrel;   a plunger disposed in the chamber of the pump barrel above the standing valve and below the upper end of the pump barrel and adapted for reciprocating movement through at least a portion of the chamber of the pump barrel;   a traveling valve located in the plunger to permit one way flow of fluid into the plunger; and   a pull rod having one end connected to the plunger and an opposite end connected to a sucker rod string to affect reciprocating movement of the plunger.