Nanofluids and methods of use for drilling and completion fluids

Abstract

Nanomaterial compositions are useful for applications in drilling and completion fluids as enhancers of electrical and thermal conductivity, emulsion stabilizers, wellbore strength improvers, drag reduction agents, wettability changers, corrosion coating compositions and the like These nanomaterials may be dispersed in the liquid phase in low volumetric fraction, particularly as compared to corresponding agents of larger size. Nanofluids (fluids containing nano-sized particles) may be used to drill at least part of the wellbore. Nanofluids for drilling and completion applications may be designed including nanoparticles such as carbon nanotubes. These fluids containing nanomaterials, such as carbon nanotubes, meet the required rheological and filtration properties for application in challenging HPHT drilling and completions operations.

What is claimed is: 
     
         1 . A drilling fluid having increased rheological stability comprising:
 a base fluid selected from the group consisting of an aqueous fluid, a non-aqueous fluid and combinations thereof, where the base fluid comprises a continuous phase;   solid particles suspended in the continuous phase; and   nanoparticles having a size less than 999 nm, selected from the group consisting of silica, magnesium oxide, iron oxide, copper oxide, zinc oxide, nickel oxide, alumina, boron, carbon black, graphene, carbon nanotubes, ferromagnetic nanoparticles, nanoplatelets, surface-modified nanoparticles, halloysite clay nanotubes, polymer-based nanoparticles, degradable nanoparticles, nanocapsules, mesoporous nanoparticles, multistimuli-responsive nanospheres, core/shell nanoparticles, and combinations thereof;   
       where the nanoparticles are present in the fluid in an amount effective to improve the rheological stability of the fluid over a temperature range from ambient up to about 320° C. and a pressure range of about atmospheric pressure up to about 350 MPa, as compared with an identical drilling fluid absent the nanoparticles. 
     
     
         2 . The drilling fluid of  claim 1  where the nanoparticles have at least one dimension less than 100 nm. 
     
     
         3 . The drilling fluid of  claim 1  further comprising a surfactant in an amount effective to suspend the nanoparticles in the base fluid. 
     
     
         4 . The drilling fluid of  claim 1  where the nanoparticles have an electrical charge. 
     
     
         5 . The drilling fluid of  claim 1  where the nanoparticles are functionalized nanoparticles having at least one functional group selected from the group consisting of sulfonate, sulfate, sulfosuccinate, thiosulfate, succinate, carboxylate, hydroxyl, glucoside, ethoxylate, propoxylate, phosphate, ethoxylate, ether, amines, amides and combinations thereof. 
     
     
         6 . The drilling fluid of  claim 1  where the nanoparticles are functionalized nanoparticles having at least two functional groups where:
 one functional group is a hydrophilic group; and 
 a second functional group is a hydrophobic group. 
 
     
     
         7 . The drilling fluid of  claim 1  where the amount of nanoparticles in the drilling fluid range from about 5 ppm to about 150,000 ppm. 
     
     
         8 . The drilling fluid of  claim 1  where the nanoparticles are functionalized nanoparticles with a polar and a non-polar group. 
     
     
         9 . The drilling fluid of  claim 1  where the nanoparticles encapsulate at least one encapsulated additive, where the at least one encapsulated additive is selected from the group consisting of wax and asphaltene inhibitors, shale stabilizers, corrosion inhibitors, rate of penetration enhancers, scale inhibitors, hydrate inhibitors, biocides, lubricants, additives for acid treatment, cross linking agents, chemicals to treat acid gases, tracers, gel forming polymers and combinations thereof. 
     
     
         10 . The drilling fluid of  claim 9  where the encapsulated additive is released from the nanoparticles by a triggering release mechanism selected from the group consisting of change of pH, change of temperature, change of electrolyte type, change of concentration, application of a magnetic field, application of a electromagnetic field, and combinations thereof. 
     
     
         11 . A drilling fluid having increased rheological stability comprising:
 a base fluid selected from the group consisting of an aqueous fluid, a non-aqueous fluid and combinations thereof, where the base fluid comprises a continuous phase;   solid particles suspended in the continuous phase; and   nanoparticles have at least one dimension less than 100 nm, selected from the group consisting of silica, magnesium oxide, iron oxide, copper oxide, zinc oxide, nickel oxide, alumina, boron, carbon black, graphene, carbon nanotubes, ferromagnetic nanoparticles, nanoplatelets, surface-modified nanoparticles, halloysite clay nanotubes, polymer-based nanoparticles, degradable nanoparticles, nanocapsules, mesoporous nanoparticles, multistimuli-responsive nanospheres, core/shell nanoparticles, and combinations thereof;   
       where the nanoparticles are present in the fluid in an amount effective to improve the rheological stability of the fluid ranging from about 5 ppm to about 150,000 ppm over a temperature range from ambient up to about 320° C. and a pressure range of about atmospheric pressure up to about 350 MPa, as compared with an identical drilling fluid absent the nanoparticles. 
     
     
         12 . The drilling fluid of  claim 11  further comprising a surfactant in an amount effective to suspend the nanoparticles in the base fluid. 
     
     
         13 . The drilling fluid of  claim 11  where the nanoparticles have an electrical charge. 
     
     
         14 . The drilling fluid of  claim 11  where the nanoparticles are functionalized nanoparticles having at least one functional group selected from the group consisting of sulfonate, sulfate, sulfosuccinate, thiosulfate, succinate, carboxylate, hydroxyl, glucoside, ethoxylate, propoxylate, phosphate, ethoxylate, ether, amines, amides and combinations thereof. 
     
     
         15 . The drilling fluid of  claim 11  where the nanoparticles are functionalized nanoparticles having at least two functional groups where:
 one functional group is a hydrophilic group; and 
 a second functional group is a hydrophobic group. 
 
     
     
         16 . The drilling fluid of  claim 11  where the nanoparticles are functionalized nanoparticles with a polar and a non-polar group. 
     
     
         17 . The drilling fluid of  claim 11  where the nanoparticles encapsulate at least one encapsulated additive, where the at least one encapsulated additive is selected from the group consisting of wax and asphaltene inhibitors, shale stabilizers, corrosion inhibitors, rate of penetration enhancers, scale inhibitors, hydrate inhibitors, biocides, lubricants, additives for acid treatment, cross linking agents, chemicals to treat acid gases, tracers, gel forming polymers and combinations thereof. 
     
     
         18 . A drilling fluid having increased rheological stability comprising:
 a base fluid selected from the group consisting of an aqueous fluid, a non-aqueous fluid and combinations thereof, where the base fluid comprises a continuous phase;   solid particles suspended in the continuous phase;   nanoparticles having a size less than 999 nm and an electrical charge, selected from the group consisting of silica, magnesium oxide, iron oxide, copper oxide, zinc oxide, nickel oxide, alumina, boron, carbon black, graphene, carbon nanotubes, ferromagnetic nanoparticles, nanoplatelets, surface-modified nanoparticles, halloysite clay nanotubes, polymer-based nanoparticles, degradable nanoparticles, nanocapsules, mesoporous nanoparticles, multistimuli-responsive nanospheres, core/shell nanoparticles, and combinations thereof; and   a surfactant in an amount effective to suspend the nanoparticles in the base fluid   
       where the nanoparticles are present in the fluid in an amount effective to improve the rheological stability of the fluid over a temperature range from ambient up to about 320° C. and a pressure range of about atmospheric pressure up to about 350 MPa, as compared with an identical drilling fluid absent the nanoparticles. 
     
     
         19 . The drilling fluid of  claim 18  where the nanoparticles have at least one dimension less than 100 nm. 
     
     
         20 . The drilling fluid of  claim 18  where the amount of nanoparticles in the drilling fluid range from about 5 ppm to about 150,000 ppm.