High rate gravel packing

Abstract

A method of gravel packing a portion of a cased wellbore proximate perforations by using coiled tubing is disclosed. The portion of the wellbore containing perforations is isolated from the portion of the wellbore below the perforations. A connection apparatus is installed between a bottom hole assembly and the coiled tubing and this connection apparatus comprises a crossover tool. The bottom hole assembly is lowered into the wellbore using the coiled tubing until the bottom hole assembly is proximate the perforations. Then, a slurry comprising a gravel and a carrier fluid is pumpdown the coiled tubing and into the annulus between the coiled tubing and the casing. A second fluid which is compatible with the slurry is pumpdown the annulus between the coiled tubing and the casing while the slurry is above the connection apparatus between the bottom hole assembly and the coiled tubing. The second fluid and the slurry mixture reduce the slurry concentration prior to reaching the perforations.

1 . A method of gravel packing a portion of a cased wellbore proximate perforations by using coiled tubing, comprising the steps of:
 isolating the portion of the wellbore containing perforations from the portion of the wellbore below the perforations;   installing connection apparatus between a bottom hole assembly and the coiled tubing;   lowering the bottom hole assembly into the wellbore using the coiled tubing until the bottom hole assembly is proximate the perforations;   pumping a slurry comprising gravel and a carrier fluid down the coiled tubing and into the annulus between the coiled tubing and the casing; and   pumping a second fluid which is compatible with the slurry down the annulus between the coiled tubing and the casing while the slurry is above the connection between the bottom hole assembly and the coiled tubing, so that the second fluid and the slurry mix to form a solution with a reduced slurry concentration prior to reaching the perforations.   
   
   
       2 . The method of  claim 1 , wherein the connection between the bottom hole assembly and the coiled tubing includes a crossover tool having pumping and non-pumping positions and the step of pumping the slurry down the coiled tubing comprises the step of shifting the crossover tool from the non-pumping to a pumping position. 
   
   
       3 . The method of  claim 2 , wherein the step of shifting the crossover tool from the non-pumping to the pumping position comprises dropping a ball down the coiled tubing at the earth's surface. 
   
   
       4 . The method of  claim 1 , wherein the slurry and the second fluid are designed to flow at a rate sufficient to break down the formation proximate the perforations. 
   
   
       5 . The method of  claim 4 , wherein the slurry comprises proppants. 
   
   
       6 . The method of  claim 1 , wherein the slurry comprises a concentration of about 0.5 to 4.0 ppa and the mixture of the slurry and the second fluid comprises a concentration of about 0.2 to 2.0 ppa. 
   
   
       7 . The method of  claim 1 , further comprising the step of circulating out the slurry by pumping it down the coiled tubing and taking returns of the slurry via the annulus between the coiled tubing and the casing, once a wellbore screenout has been obtained. 
   
   
       8 . The method of  claim 1 , further comprising the step of removing the coiled tubing and the connection device from the wellbore. 
   
   
       9 . The method of  claim 8 , further comprising the step of installing a sealing apparatus above the gravel packed bottom hole assembly. 
   
   
       10 . The method of  claim 9 , wherein the step of installing a sealing apparatus comprises the installation of a packer above the gravel packed bottom hole assembly. 
   
   
       11 . The method of  claim 9 , wherein the step of installing a sealing apparatus comprises the installation of a pack-off assembly above the gravel packed bottom hole assembly. 
   
   
       12 . A method of gravel packing a portion of a cased wellbore proximate perforations by using coiled tubing, comprising the steps of:
 installing a scaling device in the wellbore to isolate the portion of the wellbore containing perforations from the portion of the wellbore below the perforations;   installing connection apparatus between a bottom hole assembly and the coiled tubing, where the connection apparatus comprises a crossover tool having pumping and non-pumping positions;   lowering the bottom hole assembly into the wellbore using the coiled tubing until the bottom hole assembly is proximate the perforations;   shifting the crossover tool from the non-pumping to the pumping position;   pumping a slurry comprising gravel and a carrier fluid down the coiled tubing and into the annulus between the coiled tubing and the casing; and   pumping a second fluid which is compatible with the slurry down the annulus between the coiled tubing and the casing while the slurry is above the connection apparatus between the bottom hole assembly and the coiled tubing, so that the second fluid and the slurry mix to form a solution with reduced slurry concentration prior to reaching the perforations.   
   
   
       13 . The method of  claim 12 , wherein the slurry and the second fluid are designed to flow at a rate sufficient to break down the formation proximate the perforations. 
   
   
       14 . The method of  claim 12 , wherein the step of shifting the crossover tool from the non-pumping to the pumping position comprises dropping a ball down the coiled tubing at the earth's surface. 
   
   
       15 . The method of  claim 12 , wherein the slurry comprises a concentration of about 0.5 to 4.0 ppa and the mixture of the slurry and the second fluid comprises a concentration of about 0.2 to 2.0 ppa. 
   
   
       16 . The method of  claim 12 , further comprising the step of circulating out the slurry by pumping in down the coiled tubing and taking returns of the slurry via the annulus between the coiled tubing and the casing, once a wellbore screenout has been obtained. 
   
   
       17 . The method of  claim 12 , further comprising the step of removing the coiled tubing and the connection apparatus from the wellbore. 
   
   
       18 . The method of  claim 17 , further comprising the step of installing a sealing apparatus above the gravel packed bottom hole assembly. 
   
   
       19 . The method of  claim 18 , wherein the step of installing a sealing apparatus comprises the installation of a packer above the gravel packed bottom hole assembly. 
   
   
       20 . The method of  claim 18 , wherein the step of installing a sealing apparatus comprises the installation of a pack-off assembly above the gravel packed bottom hole assembly.