Application of Surfactant-based enhanced oil recovery in carbonate Reservoirs: A critical review of the opportunities and challenges

Abstract

The oil productionfromcarbonate formations is low because of complicatedcompositions, formation heterogeneity, oil-wet/mixed wet conditions, etc. Primary recovery depends on the reservoir's natural resources for production and is often supplemented by secondary recovery methods such as water flooding or immiscible gas injection to generate an artificial drive and complement reservoir energy. Tertiary recovery strategies should be used to mobilize residual oil saturation and increase oil recoveries from these reservoirs using various chemical flooding and chemical agent systems. Polymer flooding, surfactant flooding, alkali flooding, and combinations of these flooding methods are different types of Chemical floodingEOR (C-EOR) technology. Surfactant flooding procedures have been regarded as reliable EOR methodsfor field utilization because they minimize interfacial tensions and modify reservoir rock wetting characteristics, reducedcapillary forces and thus promote oil recovery. This paper provides a review of field projects and large-scale operations of surfactantfloodingin carbonate reservoirs. The fundamentalprocesses of various chemical systems, as well as the interactions of various compoundswith reservoir rocks and fluids, have been examined. After a sequence of assessment steps, the required surfactant flooding for a range of specific reservoir conditions is determined. The properties of a surfactant such as formulation and characteristics of reservoirs such as temperature, salinity, pH, rock permeability, formation type, wettability and other considerations are discussed. Moreover, since carbonate reservoirs are distinguished with a considerableheterogeneity, high temperature, and high salinity conditions, surfactant and polymer choosingfor these kind of reservoirs is a difficult process that requires experimental test to obtain the best quantity and composition of chemicals. Field project design and technical insights can be used to generate innovative strategies that will have a direct effect on the internationaloil supply in the immediate future.