This invention relates to the field of oilfield
chemistry, and discloses an
oil displacement composition and an
oil displacement agent, as well as their applications. The
oil displacement composition comprises component A and component B, wherein component A has the structure shown in Formula I, and component B has the structure shown in Formula II; wherein R1 is a C1-C8 alkanol or a C6-C8
aromatic alcohol; PO is a polyoxypropylene segment; EO is a polyoxyethylene segment; m = 1-30; n = 1-15; Y ‑ R1 is an
acid radical ion; M is an
alkali metal or
alkaline earth metal; R2 is a C1-C8
alkyl group or a C6-C8
aryl group. The oil displacement agent prepared from the oil displacement composition of this invention can be used in chemical oil displacement. This oil displacement agent is an ultra-low interfacial tension spreading type oil displacement agent, with simple composition, good
solubility, and cost
advantage. R1-O-(PO) m -(EO) n -Y ‑ M + Formula I; R2-OH Formula II.