Downhole separator

Abstract

A downhole separator includes an inner tubular member and an outer tubular member. The outer tubular member is positioned about at least a portion of the inner tubular member and connected to the inner tubular member to define an annulus between the inner tubular member and the outer tubular member. The upper end of the outer tubular is free from the inner tubular member to define a circumferential inlet between the upper end of the outer tubular member and the inner tubular member. The circumferential inlet is in fluid communication with the lower open end of the inner tubular member. Reservoir fluid passes into the annulus formed between the inner tubular member and the outer tubular member via the circumferential inlet. The reservoir fluid is guided downwardly to the opening of the inner tubular member so the fluid continues to travel up through the inner tubular member.

What is claimed is: 
     
         1 . A separator, comprising:
 an inner tubular member having an upper end, a lower end, and a sidewall extending between the upper end and the lower end, the lower end of the inner tubular member having an opening, the upper end of the inner tubular member connectable to a lower end of a tubing string positionable in a wellbore; and   an outer tubular member having an upper end, a lower end, and a sidewall extending between the upper end of the outer tubular member and the lower end of the outer tubular member, the outer tubular member positioned about at least a portion of the inner tubular member and connected to the inner tubular member to define an annulus between the inner tubular member and the outer tubular member, the upper end of outer tubular being free from the inner tubular member to define a circumferential inlet between the upper end of the outer tubular member and the inner tubular member, the circumferential inlet being in fluid communication with the lower open end of the inner tubular member,   wherein reservoir fluid passes into the annulus formed between the inner tubular member and the outer tubular member via the circumferential inlet, the reservoir fluid guided downwardly to the opening of the inner tubular member so the fluid continues to travel up through the inner tubular member.   
     
     
         2 . The separator of  claim 1 , further comprising a connector member supporting the outer tubular member relative to the inner tubular member in a way that permits fluid communication between the circumferential inlet and the opening at the lower end of the inner tubular member. 
     
     
         3 . The separator of  claim 2 , wherein the connector member is positioned between the upper end of the outer tubular member and the opening at the lower end of the inner tubular member, the connector member having a plurality of flow ports extending therethrough. 
     
     
         4 . The separator of  claim 3 , wherein the inner tubular member has at least one spiral protrusion extending outwardly from the sidewall to cooperate with an interior side of the outer tubular member to form a spiral channel, wherein reservoir fluid passes into the annulus formed between the inner tubular member and the outer tubular member via the circumferential inlet, the reservoir fluid guided downwardly into the spiral channel so the spiral channel induces a cyclonic flow that causes heavier particles to be forced outwardly and to fall to the lower end of the outer tubular member, the separated fluid flows into the lower open end of the inner tubular member so the fluid continues to travel up through the inner tubular member. 
     
     
         5 . The separator of  claim 4 , wherein a lower portion of the outer tubular member includes a funnel-shaped bore. 
     
     
         6 . The separator of  claim 5 , further comprising a collector section having an upper end connected to the lower end of the outer tubular member. 
     
     
         7 . The separator of  claim 6 , wherein the collector section comprises a tubular member having an upper end, a closed lower end, and a sidewall defining a chamber extending between the upper end and the lower end, the upper end of the collector section connected to the lower end of the outer tubular member. 
     
     
         8 . A separator, comprising:
 a tubing string positioned in a wellbore, the tubing string having an upper end and a lower end;   an inner tubular member having an upper end, a lower end, and a sidewall extending between the upper end and the lower end, the lower end of the inner tubular member having an opening, the upper end of the inner tubular member connected to the lower end of the tubing string; and   an outer tubular member having an upper end, a lower end, and a sidewall extending between the upper end of the outer tubular member and the lower end of the outer tubular member, the outer tubular member positioned about at least a portion of the inner tubular member and connected to the inner tubular member to define an annulus between the inner tubular member and the outer tubular member, the upper end of outer tubular being free from the inner tubular member to define a circumferential inlet between the upper end of the outer tubular member and the inner tubular member, the circumferential inlet being in fluid communication with the lower open end of the inner tubular member,   wherein reservoir fluid passes into the annulus formed between the inner tubular member and the outer tubular member via the circumferential inlet, the reservoir fluid guided downwardly to the opening of the inner tubular member so the fluid continues to travel up through the inner tubular member to the tubing string.   
     
     
         9 . The separator of  claim 8 , further comprising a connector member supporting the outer tubular member relative to the inner tubular member in a way that permits fluid communication between the circumferential inlet and the opening at the lower end of the inner tubular member. 
     
     
         10 . The separator of  claim 9 , wherein the connector member is positioned between the upper end of the outer tubular member and the opening at the lower end of the inner tubular member, the connector member having a plurality of flow ports extending therethrough. 
     
     
         11 . The separator of  claim 10 , wherein the inner tubular member has at least one spiral protrusion extending outwardly from the sidewall to cooperate with an interior side of the outer tubular member to form a spiral channel, wherein reservoir fluid passes into the annulus formed between the inner tubular member and the outer tubular member via the circumferential inlet, the reservoir fluid guided downwardly into the spiral channel so the spiral channel induces a cyclonic flow that causes heavier particles to be forced outwardly and to fall to the lower end of the outer tubular member, the separated fluid flows into the lower open end of the inner tubular member so the fluid continues to travel up through the inner tubular member. 
     
     
         12 . The separator of  claim 11 , wherein a lower portion of the outer tubular member includes a funnel-shaped bore. 
     
     
         13 . The separator of  claim 12 , further comprising a collector section having an upper end connected to the lower end of the outer tubular member. 
     
     
         14 . The separator of  claim 13 , wherein the collector section comprises a tubular member having an upper end, a closed lower end, and a sidewall defining a chamber extending between the upper end and the lower end, the upper end of the collector section connected to the lower end of the outer tubular member. 
     
     
         15 . The separator of  claim 8 , wherein the tubing string includes a pump assembly positioned uphole of the inner tubular member. 
     
     
         16 . The separator of  claim 15 , 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 inner tubular member;   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.