Patent ID: 10889750

Abstract:
An oil recovery composition of an aqueous solution of one or more salts and dilute polymer and processes for enhanced oil recovery using the oil recovery composition are provided. An oil recovery composition may include an aqueous solution of one or more salts having a salinity of about 4000 parts-per-million (ppm) total dissolved solids (TDS) to about 8000 ppm TDS and a polymer having a concentration of 250 ppm to 750 ppm. The one or more salts may include at least one of sodium chloride (NaCl), calcium chloride (CaCl2), magnesium chloride (MgCl2), sodium sulfate (Na2SO4) and magnesium sulfate (MgSO4). The polymer may include a copolymer of acrylamide and acrylamido tertiary butyl sulfonate (ATBS). The oil recovery compositions provided may be suited for enhancing oil recovery in carbonate reservoirs having in situ oil viscosities less than 3 centipoise (cP).