Injecting a chemical inhibitor into a wellbore

Abstract

A downhole completion assembly includes a production tubing installed in a wellbore and includes downhole production valves; a fluid conduit installed in the wellbore adjacent the production tubing and fluidly coupled, at an uphole end, to a hydraulic fluid source and a chemical inhibitor fluid source. The fluid conduit is fluidly coupled, at a downhole end, to the production tubing; and a diverter sleeve installed in or to the fluid conduit. The diverter sleeve is configured to operate: in a first state to circulate a chemical inhibitor fluid from the chemical inhibitor fluid source to the production tubing based on a first fluid pressure, and in a second state to circulate a hydraulic fluid from the hydraulic fluid source to the downhole production valves based on a second fluid pressure in the diverter sleeve greater than the first fluid pressure.

What is claimed is: 
     
         1 . A downhole completion assembly, comprising:
 at least a portion of a production tubing installed in a wellbore that extends from a terranean surface into a subterranean formation, the production tubing comprising one or more downhole production valves;   a fluid conduit installed in the wellbore adjacent the production tubing, the fluid conduit fluidly coupled, at an uphole end, to a hydraulic fluid source and a chemical inhibitor fluid source, the fluid conduit fluidly coupled, at a downhole end, to the production tubing; and   a diverter sleeve installed in or to the fluid conduit and configured to operate:
 in a first state to circulate a chemical inhibitor fluid from the chemical inhibitor fluid source, through the fluid conduit, and to the production tubing based on a first fluid pressure in the diverter sleeve, and 
 in a second state to circulate a hydraulic fluid from the hydraulic fluid source, through the fluid conduit, and to the one or more downhole production valves based on a second fluid pressure in the diverter sleeve greater than the first fluid pressure. 
   
     
     
         2 . The downhole completion assembly of  claim 1 , wherein the diverter sleeve comprises:
 an outer housing that includes a connection coupled to the fluid conduit;   an inner housing that defines a flow path in fluid communication with the fluid conduit;   a first fluid connector fluidly coupled between the flow path and the production tubing; and   a second fluid connector fluidly coupled between the flow path and the one or more downhole production valves.   
     
     
         3 . The downhole completion assembly of  claim 2 , wherein the diverter sleeve comprises:
 a plug positioned in the flow path and moveable based at least part on a fluid pressure force in flow path; and   a spring positioned to exert a spring force on the plug opposite the fluid pressure force.   
     
     
         4 . The downhole completion assembly of  claim 3 , wherein in the first state, the first fluid pressure generates the fluid pressure force on the plug, and the spring force is sufficient to urge the plug to fluidly seal the second fluid connector and fluidly couple the flow path to the first fluid connector to circulate the chemical inhibitor fluid through the flow path and to the production tubing, and
 in the second state, the second fluid pressure generates the fluid pressure force on the plug, and the fluid pressure force is sufficient to urge the plug to fluidly seal the first fluid connector and fluidly couple the flow path to the second fluid connector to circulate the hydraulic fluid through the flow path and to the one or more downhole production valves.   
     
     
         5 . The downhole completion assembly of  claim 4 , wherein the diverter sleeve comprises:
 a pair of uphole flanges comprising a first uphole flange configured to abut a second uphole flange to limit an uphole movement distance of the plug when the spring force is sufficient to urge the plug to fluidly seal the second fluid connector and fluidly couple the flow path to the first fluid connector; and   a pair of downhole flanges comprising a first downhole flange configured to abut a second downhole flange to limit a downhole movement distance of the plug when the fluid pressure force is sufficient to urge the plug to fluidly seal the first fluid connector and fluidly couple the flow path to the second fluid connector.   
     
     
         6 . The downhole completion assembly of  claim 4 , wherein the diverter sleeve comprises a fluid outlet formed through the inner housing, where the fluid outlet is positioned to fluidly couple the flow path with the first fluid connector when the spring force is sufficient to urge the plug to fluidly seal the second fluid connector and fluidly couple the flow path to the first fluid connector, and the fluid outlet is positioned to fluidly couple the flow path with the second fluid connector when the fluid pressure force is sufficient to urge the plug to fluidly seal the first fluid connector and fluidly couple the flow path to the second fluid connector. 
     
     
         7 . The downhole completion assembly of  claim 2 , further comprising a chemical injection valve fluidly coupled to the first fluid connector and the production tubing. 
     
     
         8 . The downhole completion assembly of  claim 2 , wherein the diverter sleeve comprises one or more seal stacks configured to provide a pressure tight isolation between the outer housing and the inner housing. 
     
     
         9 . The downhole completion assembly of  claim 1 , wherein the first fluid pressure is between 3,000 and 4,000 psig, and the second fluid pressure is between 9,000 and 10,000 psig. 
     
     
         10 . The downhole completion assembly of  claim 1 , wherein the hydraulic fluid comprises oil, and the chemical inhibitor fluid is configured to remove or reduce scale or asphaltene in the production tubing. 
     
     
         11 . A method, comprising:
 operating a production tubing installed in a wellbore that extends from a terranean surface into a subterranean formation to flow a production fluid through one or more downhole production valves of the production tubing; and   operating a diverter sleeve installed in or to a fluid conduit that is installed in the wellbore adjacent the production tubing, where the fluid conduit fluidly is coupled, at an uphole end, to a hydraulic fluid source and a chemical inhibitor fluid source and the fluid conduit is fluidly coupled, at a downhole end, to the production tubing, the operating comprising:
 operating the diverter sleeve in a first operational mode to circulate a chemical inhibitor fluid from the chemical inhibitor fluid source, through the fluid conduit, and to the production tubing based on a first fluid pressure in the diverter sleeve, and 
 operating the diverter sleeve in a first operational mode to circulate a hydraulic fluid from the hydraulic fluid source, through the fluid conduit, and to the one or more downhole production valves based on a second fluid pressure in the diverter sleeve greater than the first fluid pressure. 
   
     
     
         12 . The method of  claim 11 , wherein the diverter sleeve comprises an outer housing that includes a connection coupled to the fluid conduit, and an inner housing that defines a flow path in fluid communication with the fluid conduit, the method comprising:
 circulating, in the first operational mode, the chemical inhibitor fluid from the flow path to a first fluid connector fluidly coupled between the flow path and the production tubing; and   circulating, in the second operational mode, the hydraulic fluid from the flow path to a second fluid connector fluidly coupled between the flow path and the one or more downhole production valves.   
     
     
         13 . The method of  claim 12 , wherein the diverter sleeve comprises a plug positioned in the flow path and a spring, the operating comprising:
 in the first and second operational modes, exerting a fluid pressure force on an uphole side of the plug; and   in the first and second operational modes, exerting a spring force on a downhole side of the plug opposite the uphole side.   
     
     
         14 . The method of  claim 13 , wherein operating the diverter sleeve in the first operational mode comprises moving the plug with the spring force to fluidly seal the second fluid connector and fluidly couple the flow path to the first fluid connector to circulate the chemical inhibitor fluid through the flow path and to the production tubing, and
 operating the diverter sleeve in the second operational mode comprises moving the plug with the fluid pressure force to fluidly seal the first fluid connector and fluidly couple the flow path to the second fluid connector to circulate the hydraulic fluid through the flow path and to the one or more downhole production valves.   
     
     
         15 . The method of  claim 14 , wherein operating the diverter sleeve in the first operational mode comprises adjusting the diverter sleeve to abut a first uphole flange of an uphole pair of flanges with a second uphole flange of the uphole pair of flanges to limit an uphole movement distance of the plug; and
 operating the diverter sleeve in the second operational mode comprises adjusting the diverter sleeve to abut a first downhole flange of a pair of downhole flanges with a second downhole flange of the pair of downhole flanges to limit a downhole movement distance of the plug.   
     
     
         16 . The method of  claim 14 , wherein operating the diverter sleeve in the first operational mode comprises moving the plug with the spring force to align a fluid outlet of the inner housing with the first fluid connector to fluidly seal the second fluid connector and fluidly couple the flow path to the first fluid connector, and
 operating the diverter sleeve in the second operational mode comprises moving the plug with the fluid pressure force to align the fluid outlet with the second fluid connector to fluidly seal the first fluid connector and fluidly couple the flow path to the second fluid connector.   
     
     
         17 . The method of  claim 12 , wherein operating the diverter sleeve in the first operational mode comprises circulating the chemical inhibitor fluid from the first fluid connection to a chemical injection valve in the production tubing. 
     
     
         18 . The method of  claim 12 , further comprising creating a pressure tight isolation between the outer housing and the inner housing with one or more seal stacks. 
     
     
         19 . The method of  claim 11 , wherein the first fluid pressure is between 3,000 and 4,000 psig, and the second fluid pressure is between 9,000 and 10,000 psig. 
     
     
         20 . The method of  claim 11 , further comprising removing or reducing scale or asphaltene in the production tubing with the chemical inhibitor fluid circulated in the first operational mode.