Research on the technologies of improving recovery efficiency after polymer flooding

After polymer flooding, water cut rapidly rise during succedent water flooding. In order to study the technological measures of enhancing recovery efficiency, the heterogeneous reservoir composed of high, medium and low permeable formations are simulated, and three combination technologies are tested. The testing results show that, after polymer flooding, if only deep profile control is adopted, the effects of deep profile control on plugging high permeability reservoirs, controlling the water intake capacity of high permeability pore passages and increasing the sweep efficiency of water flooding are not obvious whether the duration of water flooding is long or short. If water flooding carry out some time after polymer flooding, flocculant and hardening agent are added, which can effectively improve water flooding profile and increase the sweep efficiency of succedent water flooding, so the recovery efficiency is greatly increased.