Method for Pumping Hydrocarbons

Abstract

A method of pumping a hydrocarbon fluid from a wellbore ( 4 ) and a hydrocarbon completion ( 1 ) implementing the methodology is described. The method comprises deploying a tubing string ( 7 ) and a first pump system ( 15 ), in fluid communication with the tubing string, within a wellbore. The first pump system is employed to generate a production fluid ( 17 ) by heating the hydrocarbon fluid as it is pumped into the tubing string so as to form a counter current heat exchanger between the production fluid within the tubing string and the hydrocarbon fluid located within the wellbore. The counter current heat exchanger provides a means for preheating the hydrocarbon fluid before it reaches the first pump system. As a result the viscosity of the hydrocarbon fluid is reduced thus making it easier to pump to the surface. The method finds particular application within horizontal, high angle or vertical wells in heavy or extra heavy oil fields.

1 . A method of pumping a hydrocarbon fluid from a wellbore the method comprising:
 deploying a tubing string within the wellbore;   deploying within the wellbore a first pump system that is in fluid communication with the tubing string;   employing the first pump system to generate a production fluid by heating the hydrocarbon fluid as it is pumped into the tubing string; and   forming a counter current heat exchanger between the production fluid within the tubing string and the hydrocarbon fluid located within an annulus between the tubing string and the wellbore to heat the hydrocarbon fluid before it enters the pump system.   
     
     
         2 . A method of pumping a hydrocarbon fluid as claimed in  claim 1  wherein the hydrocarbon fluid comprises a fluid having a viscosity of greater than 1,000 cP. 
     
     
         3 . A method of pumping a hydrocarbon fluid as claimed in  claim 1  wherein the hydrocarbon fluid comprises a fluid having a viscosity of greater than 2,000 cP. 
     
     
         4 . A method of pumping a hydrocarbon fluid as claimed in  claim 1  wherein the hydrocarbon fluid comprises a fluid having a viscosity of greater than 20,000 cP. 
     
     
         5 . A method of pumping a hydrocarbon fluid as claimed in  claim 1  wherein the first pump system is deployed such that one or more wellbore perforations are located between the first pump system and the surface of the wellbore. 
     
     
         6 . A method of pumping a hydrocarbon fluid as claimed in  claim 1  wherein the first pump system is located 75% to 95% of the way along the wellbore. 
     
     
         7 . A method of pumping a hydrocarbon fluid as claimed in  claim 1  wherein the hydrocarbon fluid is be heated to over 150° C. as it is pumped into the tubing string assembly. 
     
     
         8 . A method of pumping a hydrocarbon fluid as claimed in  claim 1  wherein the hydrocarbon fluid is be heated to over 300° C. as it is pumped into the tubing string assembly. 
     
     
         9 . A method of pumping a hydrocarbon fluid as claimed in  claim 1  wherein the method further comprises changing the operating parameters of a pump assembly of the pump first system so as to provide a means for optimizing the pumping of the hydrocarbon fluid. 
     
     
         10 . A method of pumping a hydrocarbon fluid as claimed in  claim 9  wherein the method comprises changing the operating frequency of the pump assembly. 
     
     
         11 . A method of pumping a hydrocarbon fluid as claimed in  claim 9  wherein the method comprises altering the operating point of the pump assembly along its head capacity curve. 
     
     
         12 . A method of pumping a hydrocarbon fluid as claimed in  claim 1  wherein the method further comprises deploying a first diverter located between the first pump system and the tubing string so as to provide a means for selectively establishing fluid communication between the first pump system and the tubing string. 
     
     
         13 . A method of pumping a hydrocarbon fluid as claimed in  claim 12  wherein the method further comprises deploying a first bypass tubing with the first diverter so as to provide a means for selectively establishing fluid communication between the first bypass tubing and the tubing string. 
     
     
         14 . A method of pumping a hydrocarbon fluid as claimed in  claim 1  wherein the method further comprises deploying a second pump system within the wellbore that is in fluid communication with the tubing string. 
     
     
         15 . A method of pumping a hydrocarbon fluid as claimed in  claim 14  wherein the second pump system is in fluid communication with the tubing string via the first bypass tubing. 
     
     
         16 . A method of pumping a hydrocarbon fluid as claimed in  claim 14  wherein the method further comprises deploying a second diverter located between the second pump system and the tubing string so as to provide a means for selectively establishing fluid communication between the second pump system and the tubing string. 
     
     
         17 . A method of pumping a hydrocarbon fluid as claimed in  claim 16  wherein the method further comprises deploying a second bypass tubing with the second diverter so as to provide a means for selectively establishing fluid communication between the second bypass tubing and the tubing string. 
     
     
         18 . A hydrocarbon completion suitable for pumping a hydrocarbon fluid from a wellbore the completion comprising:
 a tubing string deployed within the wellbore   a first pump system deployed within the wellbore that is in fluid communication with the tubing string,   wherein the first pump system is employed to generate a production fluid by heating the hydrocarbon fluid as it is pumped into the tubing string and the production fluid within the tubing string forms a counter current heat exchanger with the hydrocarbon fluid located within an annulus between the tubing string and the wellbore to heat the hydrocarbon fluid before it enters the pump system.   
     
     
         19 . A hydrocarbon completion as claimed in  claim 18  wherein the first pump system comprises a pump assembly and a motor. 
     
     
         20 . A hydrocarbon completion as claimed in  claim 19  wherein the first pump system further comprises a cooling shroud that depends from the pump assembly so as to define a flow path that requires the hydrocarbon fluid to pass over the motor before entering the pump assembly. 
     
     
         21 . A hydrocarbon completion as claimed in  claim 19  wherein a protector seal module is located between the pump assembly and the motor. 
     
     
         22 . A hydrocarbon completion as claimed in  claim 18  wherein the motor comprises a dual-helix axial pump. 
     
     
         23 . A hydrocarbon completion as claimed in  claim 18  wherein the hydrocarbon completion further comprises a control system that provides a means for changing the operating parameters of a pump assembly of the pump first system so as to optimize the hydrocarbon fluid production from the wellbore. 
     
     
         24 . A hydrocarbon completion as claimed in  claim 23  wherein the control system provide a means for changing the operating frequency of the pump assembly. 
     
     
         25 . A hydrocarbon completion as claimed in  claim 23  wherein the control system provides a means for controlling a choke so as to alter the operating point of the pump assembly along its head capacity curve. 
     
     
         26 . A hydrocarbon completion as claimed in  claim 18  wherein the hydrocarbon completion further comprises a first diverter located between the first pump system and the tubing string. 
     
     
         27 . A hydrocarbon completion as claimed in  claim 26  wherein the hydrocarbon completion further comprises a first bypass tubing connected to the first diverter. 
     
     
         28 . A hydrocarbon completion as claimed in  claim 18  wherein the hydrocarbon completion further comprises a second pump system within the wellbore that is in fluid communication with the tubing string. 
     
     
         29 . A hydrocarbon completion as claimed in  claim 28  wherein the second pump system is in fluid communication with the tubing string via the first bypass tubing. 
     
     
         30 . A hydrocarbon completion as claimed in  claim 28  wherein the hydrocarbon completion further comprises a second diverter located between the second pump system and the tubing string. 
     
     
         31 . A hydrocarbon completion as claimed in  claim 30  wherein the hydrocarbon completion further comprises a second bypass tubing connected to the second diverter.