Treatment fluid

Abstract

Proppant transport assist in low viscosity treatment fluids. Treatment fluids and methods use fiber containing 0.1 to 20 wt % silicones to inhibit proppant settling without an unacceptable bridging tendency.

1 . A treatment fluid, comprising:
 a low viscosity carrier fluid having a viscosity less than 50 mPa-s at a shear rate of 170 s −1  and a temperature of 25° C.;   proppant dispersed in the carrier fluid; and   fiber containing 0.1 to 20 wt. % silicones dispersed in the carrier fluid.   
     
     
         2 . The treatment fluid of  claim 1 , wherein the carrier fluid is slickwater, brine, or linear gel. 
     
     
         3 . (canceled) 
     
     
         4 . The treatment fluid of  claim 1 , comprising from 0.06 to 1 kg/L of the proppant based on the total volume of the carrier fluid (from 0.5 to 8.3 ppa, pounds proppant added per gallon of carrier fluid). 
     
     
         5 . The treatment fluid of  claim 1 , wherein the fiber is dispersed in the carrier fluid in an amount effective to inhibit settling of the proppant inn the carrier fluid. 
     
     
         6 . (canceled) 
     
     
         7 . The treatment fluid of  claim 1 , wherein the fiber is dispersed in the carrier fluid in an amount insufficient to cause bridging. 
     
     
         8 . The treatment fluid of  claim 1 , wherein the fiber is dispersed in the carrier fluid in an amount effective to inhibit settling of the proppant and in an amount insufficient to cause bridging. 
     
     
         9 . (canceled) 
     
     
         10 . (canceled) 
     
     
         11 . The treatment fluid of  claim 1 , comprising from 1.2 to 12 g/L of the fibers based on the total volume of the carrier fluid (from 10 to 100 ppt, pounds per thousand gallons of carrier fluid). 
     
     
         12 . The treatment fluid of  claim 1 , comprising less than 4.8 g/L of the fibers based on the total volume of the carrier fluid (less than 40 ppt). 
     
     
         13 . The treatment fluid of  claim 1 , wherein the fibers are crimped Staple fibers. 
     
     
         14 . The treatment fluid of  claim 1 , wherein the fibers are crimped staple fibers comprising from 1 to 10 crimps/cm of length, a crimp angle from 45 to 160 degrees, an average extended length of fiber of from 3 to 15 mm, a mean diameter of from 8 to 40 microns, or a combination thereof. 
     
     
         15 . (canceled) 
     
     
         16 . The treatment fluid of  claim 1 , wherein the fibers comprise polyester. 
     
     
         17 . The treatment fluid of  claim 1 , wherein the fibers comprise polyester wherein the polyester undergoes hydrolysis at a temperature of less than 93° C. as determined by heating 10 g of the fibers in 1 L deionized water until the pH of the water is less than 3. 
     
     
         18 . The treatment fluid of  claim 1 , wherein the fibers comprise polyester wherein the polyester undergoes hydrolysis at a temperature of between 93° C. and 149° C. as determined by heating 10 g of the fibers in 1 L deionized water until the pH of the water is less than 3. 
     
     
         19 . (canceled) 
     
     
         20 . The treatment fluid of  claim 1 , wherein the fiber is selected from the group consisting of polylactic acid (PLA), polyglycolic acid (PGA), copolymers of PLA and PGA, polyethylene terephthalate (PET), polyester, polyamide, polycaprolactam and polylactone, poly(butylene) succinate polydioxanone, glass, ceramics, carbon (including carbon-based compounds), elements in metallic form, metal alloys, wool, basalt, acrylic, polyethylene, polypropylene, novoloid resin, polyphenylene sulfide, polyvinyl chloride, polyvinylidiene chloride, polyurethane, polyvinyl alcohol, polybenzimidazole, polyhydroquinone-diimidazopyridine, poly(p-phenylene-2,6-benzobisoxazole), rayon, cotton, cellulose and other natural fibers, rubber, and combinations thereof. 
     
     
         21 . The treatment fluid of  claim 1 , further comprising a friction reducer. 
     
     
         22 . The treatment fluid of  claim 1 , wherein the fiber containing silicones is obtained by melt extrusion. 
     
     
         23 . The treatment fluid of  claim 1 , wherein the silicone is a linear polysiloxane. 
     
     
         24 . The treatment fluid of  claim 1 , wherein the silicone has an average molecular weight of from about 100 000 g/mol to about 900 000 g/mol. 
     
     
         25 . A method to treat a subterranean formation penetrated by a wellbore, comprising:
 injecting a treatment fluid into the subterranean formation to form a hydraulic fracture system, wherein the treatment fluid comprises:
 a low viscosity carrier fluid having a viscosity less than 50 mPa-s at a shear rate of 170 s −1  and a temperature 25° C.; 
 proppant dispersed in the carrier fluid; and 
 fiber containing 0.1 to 20 wt % silicones dispersed in the carrier fluid; and 
   maintaining a rate of the injection of the treatment fluid to avoid bridging in the wellbore.   
     
     
         26 . The method of  claim 25 , further comprising injecting a pre-pad, pad, tail or flush stage or a combination thereof, optionally comprising the fibers. 
     
     
         27 . The method of  claim 25 , wherein the treatment fluid comprises from 0.06 to 1 kg/L, of the proppant based on the total volume of the carrier fluid (from 0.5 to 8.3 ppa pounds proppant added per gallon of carrier fluid). 
     
     
         28 . The method of  claim 25 , wherein the treatment fluid comprises less than 4.8 g/L of the fibers based on the total volume of the carrier fluid (less than 40 ppt). 
     
     
         29 . The method of  claim 25 , wherein the fibers comprise polyester and further comprising hydrolyzing the fibers downhole after the injection. 
     
     
         30 . The method of  claim 25 , wherein the fiber is present in the treatment fluid in an amount effective to inhibit settling of the proppant. 
     
     
         31 . The method according to  claim 25 , wherein the injection of the treatment fluid is done heterogeneously by alternating proppant-laden pulses and proppant lean pulses. 
     
     
         32 . A method to inhibit proppant settling in a treatment fluid circulated in a wellbore, the treatment fluid comprising the proppant dispersed in a low viscosity carrier fluid having a viscosity less than 50 mPa-s at a shear rate of 170 s −1  and a temperature of 25° C., comprising:
 dispersing fiber containing 0.1 to 20 wt % silicones in the carrier fluid in an amount effective to inhibit settling of the proppant; and 
 maintaining a rate of the circulation to avoid bridging in the wellbore. 
 
     
     
         33 . The method of  claim 32 , wherein the treatment fluid further comprises a friction reducer. 
     
     
         34 . A system to treat a subterranean formation, comprising:
 a subterranean formation penetrated by a wellbore;   a anent fluid injection unit to supply a treatment fluid stage, comprising proppant in a low viscosity carrier fluid, to the formation above a fracturing pressure to form a fracture system; and   a fiber supply unit to introduce fiber containing 0.1 to 0.20 wt % silicones into the treatment fluid.   
     
     
         35 . The system of  claim 34 , wherein the introduction of the fiber into the treatment fluid is in an amount suitable ID inhibit proppant settling, and wherein the supply of the treatment fluid stage to the formation is at a flow rate sufficient to avoid inducing bridging.