System, method, and apparatus for hydraulic fluid pressure sweep of a hydrocarbon formation within a single wellbore

Abstract

A system for recovering production fluid includes a return string for receiving fluid from a lateral section of a wellbore. The return string can extend from a surface of a terrestrial formation through at least a portion of the wellbore. The system also includes an injection string for communicating fluid from the surface of the terrestrial formation to the lateral section of the wellbore. The injection string includes a first injection string section located at a distal end of the injection string and for communicating fluid through at least a portion of the lateral section of the wellbore. The injection string includes a second injection string section located at a proximal end of the injection string and for communicating fluid from the surface of the terrestrial formation to the first injection string section. The second injection string section includes a smaller cross-sectional area than the first injection string section.

What is claimed is: 
     
         1 . A system for recovering production fluid from a well, the system comprising:
 a return string for receiving fluid from a lateral section of a wellbore, wherein the return string is configured to extend from a surface of a terrestrial formation through at least a portion of the wellbore; and   an injection string for communicating fluid from the surface of the terrestrial formation to the lateral section of the wellbore, wherein the injection string comprises:
 a first injection string section located at a distal end of the injection string and for communicating fluid through at least a portion of the lateral section of the wellbore, wherein the first injection string section includes a first cross-sectional area, and 
 a second injection string section located at a proximal end of the injection string and for communicating fluid from the surface of the terrestrial formation to the first injection string section, wherein the second injection string section includes a second cross-sectional area that is less than the first cross-sectional area. 
   
     
     
         2 . The system of  claim 1 , wherein when the return string receives fluid from the wellbore, a hydrostatic pressure decreases within the lateral section of the wellbore. 
     
     
         3 . The system of  claim 1 , wherein when the return string receives fluid from the wellbore, an underbalanced circulation stream forms within the lateral section of the wellbore. 
     
     
         4 . The system of  claim 3 , wherein a velocity of the underbalanced circulation stream is at least about 50 feet per minute (fpm). 
     
     
         5 . The system of  claim 1 , wherein when the injection string communicates fluid to the lateral section of the wellbore, a pressure within the injection string is at least about 400 pounds per square inch (psi) less than a pressure within a fluid reservoir that is adjacent the lateral section of the wellbore. 
     
     
         6 . The system of  claim 1 , further comprising an artificial lift positioned in fluid communication with the return string and for drawing fluid from the wellbore into the return string. 
     
     
         7 . The system of  claim 1 , wherein the first injection string section is configured to removably attached to the second injection string section. 
     
     
         8 . A method for removing an obstruction in a wellbore using a production fluid recovery system, the method comprising:
 extending an injection string from a surface of a terrestrial formation and through at least a portion of the lateral section of the wellbore to communicate fluid to the lateral section of the wellbore, wherein the injection string comprises:
 a first injection string section located at a distal end of the injection string and for communicating fluid through at least the portion of the lateral section of the wellbore, wherein the first injection string section includes a first cross-sectional area, and 
 a second injection string section located at a proximal end of the injection string and for communicating fluid from the surface of the terrestrial formation to the first injection string section, wherein the second injection string section includes a second cross-sectional area that is less than the first cross-sectional area; 
   communicating fluid through injection string;   detecting an obstruction within the wellbore; and   injecting a treatment fluid into the injection string in response to detecting the obstruction in the wellbore, wherein the treatment fluid injected into the injection string is to remove at least some of the obstruction from the wellbore and achieve an underbalance low pressure circulation stream in the lateral section of the wellbore.   
     
     
         9 . The method of  claim 8 , further comprising extending a return string from the surface of the terrestrial formation and through at least a portion of the wellbore, wherein the return string is for receiving fluid from the lateral section of the wellbore. 
     
     
         10 . The method of  claim 9 , further comprising:
 positioning an artificial lift into fluid communication with the return string to draw fluid into the return string; and   performing at least one of injecting the treatment fluid into the injection string or directing the artificial lift to adjust a flow rate of fluid that is received by the return string to remove at least some of the obstruction from the wellbore and achieve an underbalance low pressure circulation stream in the lateral section of the wellbore.   
     
     
         11 . The method of  claim 8 , wherein detecting the obstruction within the wellbore comprises detecting at least one of a location of the obstruction or a type of the obstruction. 
     
     
         12 . The method of  claim 11 , wherein detecting at least one of a location of the obstruction or the type of the obstruction is based on at least one of a location of one or more sensors within the wellbore or a pressure, a fluid velocity, a volumetric flow rate, or a temperature sensed by one or more sensors within the wellbore. 
     
     
         13 . The method of  claim 8 , wherein the treatment fluid comprises at least one of a hot treatment fluid, a chemical treatment fluid, or an acidic chemical treatment fluid, 
     
     
         14 . A system for recovering production fluid from a well, the system comprising:
 a return string for receiving fluid from a lateral section of a wellbore, wherein the return string is configured to extend from a surface of a terrestrial formation through at least a portion of the wellbore;   an injection string for communicating fluid from the surface of the terrestrial formation to the lateral section of the wellbore, wherein the injection string comprises:
 a first injection string section located at a distal end of the injection string and for communicating fluid through at least a portion of the lateral section of the wellbore, wherein the first injection string section includes a first cross-sectional area, and 
 a second injection string section located at a proximal end of the injection string and for communicating fluid from the surface of the terrestrial formation to the first injection string section, wherein the second injection string section includes a second cross-sectional area that is less than the first cross-sectional area; and 
   a packer positioned within the lateral section of the wellbore to fluidly divide the lateral section of the wellbore into a first lateral section and a second lateral section, wherein the packer includes an aperture that receives the first injection string section from the second lateral section and permits the first injection string section to extend into the first lateral section.   
     
     
         15 . The system of  claim 14 , wherein when fluid is received by the first lateral section from the first injection string section, a hydrostatic pressure within the first lateral section increases and forces production fluid adjacent to the lateral section of the wellbore to move away from the first lateral section and into the second lateral section. 
     
     
         16 . The system of  claim 15 , further comprising a flow valve positioned along the first injection string section, wherein the flow valve controls a volume of fluid communicated from the first injection string section to the first lateral section. 
     
     
         17 . The system of  claim 15 , further comprising a flow valve positioned along the first injection string section and within the second lateral section, wherein the flow valve controls a volume of fluid communicated from the first injection string section to the first lateral section, and wherein the flow valve controls a volume of fluid communicated from the first injection string section to the second lateral section creating an underbalanced circulation stream in the second lateral section. 
     
     
         18 . The system of  claim 14 , wherein the lateral section of the wellbore comprises a liner, and wherein the first cross-section area of the first injection string section reduces a cross-sectional area of an annulus between the liner and the first injection string section. 
     
     
         19 . The system of  claim 14 , wherein the second cross-sectional area of the second injection string section creates a restriction in the injection string to counteract hydrostatic pressure from a weight of fluid inside the lateral section of the wellbore. 
     
     
         20 . The system of  claim 14 , wherein a pressure difference between the first injection string section and the second injection string section is at least about 50%.