The Research of Displacement Efficiency for Binary Combination Flooding in Offshore Heterogeneous Reservoirs

Abstract

Aim at the reservoirs condition of high porosity, high permeability, high viscosity of crude oil in the offshore oilfield, this paper used two-dimensional heterogeneous physical model to conduct laboratory displacement experiments which contain water flooding, polymer flooding and binary combination flooding for offshore heterogeneous reservoirs, studied the displacement efficiency of the binary combination flooding after polymer flooding in offshore oilfield. The experiment results showed that final recovery efficiency of binary combination flooding after polymer flooding was 64.98% which is higher 31.85% than water flooding and higher 19.74% than polymer flooding; analyzed the distribution diagram of saturation at every stage, the swept efficiency of every layer respectively is 97.89%, 94.58%, 86.45%，and the oil saturation decreased in the swept area, which turned out that binary combination flooding could not only enlarge the swept volume, but also could enhance the displacement efficiency and the main effect is in low permeability layer.