Concentric coil tubing deployment for hydraulic fracture application

Abstract

A method and system for treating a portion of a wellbore. The system includes a coiled tubing string having two fluid flow areas and a valve configured to control the fluid flow out of both flow areas. The system may include at least one isolation element used to isolate a portion of a wellbore. The isolated portion of the wellbore may be treated by pumping fluid down one or both of the flow areas. The valve may be actuated to permit fluid to be pumped down one flow area while fluid is pumped up the other flow area, which may be used to clean out a screen out, treatment, proppant, and/or solids in the wellbore. The coiled tubing string with two fluid flow areas may be used to treat, stimulate, and/or fracture a portion of a wellbore and provide cleanout capabilities, if required.

What is claimed is: 
     
         1 . A method of treating a wellbore comprising:
 positioning an end of a coiled tubing string adjacent a portion of a wellbore, the coiled tubing string having a first flow area, a second flow area, and a valve configured to control flow out of the first and second flow areas into the portion of the wellbore; and   treating the portion of the wellbore by pumping fluid down at least one of the first and second flow areas.   
     
     
         2 . The method of  claim 1 , wherein treating the portion of the wellbore further comprising pumping fluid down both the first flow area and second flow area. 
     
     
         3 . The method of  claim 2 , further comprising isolating the portion of the wellbore prior to treating the portion of the wellbore. 
     
     
         4 . The method of  claim 2 , wherein isolating the portion of the wellbore further comprises setting a plurality of isolating elements. 
     
     
         5 . The method of  claim 3 , wherein the valve is proximal the end of the coiled tubing string. 
     
     
         6 . The method of  claim 3 , further comprising actuating the valve and pumping fluid up the second flow area while pumping fluid down the first flow area. 
     
     
         7 . The method of  claim 3 , wherein the valve permits fluid and particulates in the portion of the wellbore to flow up the second flow area. 
     
     
         8 . The method of  claim 6 , wherein treating further comprises fracturing a formation adjacent the portion of the wellbore. 
     
     
         9 . The method of  claim 8 , wherein a screen out has formed in a fracture during the fracturing of the formation. 
     
     
         10 . The method of  claim 9 , further comprising cleaning the screen out from the portion of the wellbore. 
     
     
         11 . The method of  claim 10 , wherein actuating the valve and pumping fluid up the second flow path cleans out the screen out. 
     
     
         12 . A system to treat a portion of a wellbore comprising:
 a coiled tubing string having a first flow area and a second flow area; and   at least one valve configured to control flow of both the first and second flow areas out of the coiled tubing string.   
     
     
         13 . The system of  claim 12 , further comprising at least one isolation element. 
     
     
         14 . The system of  claim 13 , wherein the valve is positioned proximate an end of the coiled tubing string. 
     
     
         15 . The system of  claim 14 , further comprising at least one port that permits communication from the first flow area and an exterior of the coiled tubing string and at least one port that permits communication from the second flow area and the exterior of the coiled tubing string, wherein the at least one valve is configured to control flow out both ports. 
     
     
         16 . The system of  claim 15 , wherein the at least one isolation element may be actuated to isolate a portion of a wellbore. 
     
     
         17 . The system of  claim 16 , wherein fluid may be pumped down the first and second flow areas from a surface location to treat the isolated portion of the wellbore. 
     
     
         18 . The system of  claim 17 , wherein the valve may be actuated so that fluid may be pumped down from the surface in the first flow area and pumped up to the surface in the second flow area. 
     
     
         19 . The system of  claim 18 , wherein a formation of the portion of the wellbore may be fractured or stimulated by pumping fluid down both the first and second flow areas. 
     
     
         20 . The system of  claim 19 , wherein fluid pumped up to the surface in the second flow area may be used to remove a screen out of a fracture of the portion of the wellbore.