Downhole Delivery Of Chemicals With A Micro-Tubing System

Abstract

A technique utilizes micro-tubing to facilitate performance of a well treatment in which the micro-tubing is deployed for cooperation with a larger tubing, such as a coiled tubing positioned in wellbore. The micro-tubing is used to deliver a separated chemical downhole to modify a property of a treatment fluid used in performing a desired well treatment operation at a desired treatment region along the wellbore. A variety of additional components may be combined with the micro-tubing to further facilitate the treatment application.

What is claimed is: 
     
         1 . A method of performing a well treatment, comprising:
 routing a micro-tubing down through a coiled tubing deployed in wellbore;   employing a securing mechanism to secure a lower end of the micro-tubing proximate a discharge region of the coiled tubing;   positioning a communication line within the micro-tubing; and   delivering treatment fluids downhole through the micro-tubing and through an interior of the coiled tubing located between the micro-tubing and an interior surface of the coiled tubing, the treatment fluids being dissimilar.   
     
     
         2 . The method as recited in  claim 1 , wherein routing comprises pumping the micro-tubing down through the coiled tubing via a velocity booster coupled to a lead end fixture of the micro-tubing. 
     
     
         3 . The method as recited in  claim 1 , wherein positioning comprises positioning a fiber optic communication line within the micro-tubing. 
     
     
         4 . The method as recited in  claim 1 , wherein delivering comprises delivering a treatment fluid through the micro-tubing which alters the properties of the overall well treatment. 
     
     
         5 . The method as recited in  claim 1 , wherein routing comprises routing a plurality of micro-tubings down through the coiled tubing. 
     
     
         6 . The method as recited in  claim 1 , further comprising distributing treatment fluid from the micro-tubing, through a plurality of perforations, and into a mixing region for mixing with dissimilar treatment fluid delivered through the interior of the coiled tubing between the micro-tubing and the interior surface of the coiled tubing. 
     
     
         7 . The method as recited in  claim 1 , further comprising providing a sensor system downhole coupled to the communication line. 
     
     
         8 . The method as recited in  claim 1 , further comprising utilizing the communication line to power a downhole tool. 
     
     
         9 . The method as recited in  claim 2 , wherein pumping comprises pumping down the micro-tubing with a pump-down plug having at least one burst disc which may be ruptured to enable delivery of at least one type of fluid. 
     
     
         10 . The method as recited in  claim 1 , further comprising coupling the micro-tubing and the communication line to a retrievable delivery and electronics package. 
     
     
         11 . The method as recited in  claim 1 , further comprising attaching a canister containing an additional treatment fluid to an end of the micro-tubing and controlling delivery of the additional treatment fluid with a valve. 
     
     
         12 . A method of performing a well treatment, comprising:
 deploying a micro-coil tubing and a larger tubing downhole to a well treatment region of a wellbore;   delivering a treatment fluid downhole through the larger tubing;   using the micro-coil tubing to deliver a chemical downhole for combination with the treatment fluid at the well treatment region, the chemical being selected to modify a property of the treatment fluid; and   communicating signals along the larger tubing via a communication line.   
     
     
         13 . The method as recited in  claim 12 , wherein deploying comprises deploying the larger tubing in the form of coiled tubing. 
     
     
         14 . The method as recited in  claim 12 , wherein deploying comprises pumping the micro-coil tubing down through an interior of the larger tubing. 
     
     
         15 . The method as recited in  claim 12 , wherein deploying comprises deploying the micro-coil tubing along an exterior of the larger tubing. 
     
     
         16 . The method as recited in  claim 12 , further comprising routing the communication line downhole through the micro-coil tubing. 
     
     
         17 . The method as recited in  claim 12 , further comprising forming the micro-coil tubing from a thermoplastic material. 
     
     
         18 . The method as recited in  claim 12 , wherein using comprises delivering the chemical downhole through the micro-coil tubing in the form of an additive comprising one of: a crosslinker, a breaker, an HT stabilizer, a corrosion inhibitor, a pH adjustor, a rheology enhancer, or an enzyme. 
     
     
         19 . The method as recited in  claim 12 , wherein using comprises delivering the chemical downhole through the micro-coil tubing in the form of a tracer for monitoring the well and the well treatment. 
     
     
         20 . The method as recited in  claim 12 , wherein using comprises delivering the chemical downhole into a mixing region with a desired turbulent flow pattern. 
     
     
         21 . The method as recited in  claim 12 , further comprising detecting electrical properties of a surrounding formation by using conductive and nonconductive portions of the micro-coil tubing. 
     
     
         22 . A system for treating a well, comprising:
 a coiled tubing deployed in a wellbore;   a micro-tubing sized to enable deployment along an interior of the coiled tubing;   a securing mechanism to secure a downhole end of the micro-tubing proximate an end of the coiled tubing; and   an end fixture coupled to the micro-tubing and located downhole to control the discharge and mixing of chemicals separately delivered downhole through the coiled tubing and the micro-tubing to modify a well treatment.   
     
     
         23 . The system as recited in  claim 22 , wherein the micro-tubing is a non-metallic tubing deployed in the coiled tubing and held by the securing mechanism. 
     
     
         24 . The system as recited in  claim 22 , wherein the end fixture comprises a plurality of openings located at positions 360° around a mixing chamber. 
     
     
         25 . The system as recited in  claim 22 , wherein the end fixture comprises a plurality of vanes oriented to facilitate mixing of a chemical additive, delivered through the micro-tubing, with a separate well treatment fluid delivered through the coiled tubing.