Fluid composition for stimulation in the field of oil or gas production
View Patent ↗The present invention relates to filamentous polymer particles useful in oil, condensate or gas recovery from subterranean locations as hydraulic fracturing fluids, diverting fluids, fluids that make it possible to improve the distribution and the flow profiles of the fluids or products injected (referred to as conformance fluids) or permeability control fluids, sand control gravel pack placement fluids, acid fracturing fluids, and the like. These fluids are stimulation fluids injected in wells which serve also as producing wells for the hydrocarbons initially present in the subterranean formations.
1. A composition comprising water, dissolved salts, filamentous polymeric particles and solids particles other than the filamentous polymeric particles, wherein the filamentous polymeric particles are cylindrical fibers with a diameter ranging from 5 nm to 200 nm inclusive and a length ranging from 500 nm to 200 μm and consist of block copolymers synthesized by controlled radical emulsion polymerization.
2. A composition according to claim 1 , further comprising dissolved acids.
3. A composition according to claim 1 , wherein the filamentous polymeric particles consist of block copolymers prepared by controlled radical emulsion polymerization performed using at least one hydrophobic monomer in the presence of water and a water-soluble macro-initiator derived from a nitroxide, or synthesized by radical polymerization with Reversible Addition Fragmentation Transfer (RAFT) performed using at least one hydrophobic monomer in the presence of water and a water-soluble macromolecular RAFT agent.
4. A composition according to claim 1 , wherein the salts include monovalent and/or divalent and/or trivalent ions.
5. A composition according to claim 1 wherein the weight percentage of filamentous polymeric particles compared to the weight of the composition without the solid particles other than the filamentous polymeric particles is between 0.05% and 20% and the weight percentage of dissolved salts ranges from 0.1% to salt saturation concentration.
6. A composition according to claim 1 , further comprising at least one additional component selected from the group consisting of oxygen scavengers, pH buffers, wetting agents, foamers, corrosion inhibitors, defoamers and antifoams, scale inhibitors, biocides, crosslinkers, gel breakers, non emulsifiers, fluid loss control additives, and injected gas bubbles.
7. A hydraulic fracturing fluid, diverting fluid, conformance fluid, permeability control fluid, sand control gravel pack placement fluid, or acid fracturing fluid containing the composition of claim 1 .
8. A method comprising using the composition of claim 1 as a hydraulic fracturing fluid.
9. A method of preparing a fluid according to claim 7 comprising using an aqueous composition extracted through a well from a subterranean formation.
10. A process of fracturation of a subterranean formation comprising using a composition according to claim 1 .