Due to the heterogeneity of the formation of injection wells in BZ oilfield

the single acidification and profile adjustment were impossible to increase the injection and decrease the interlayer contradiction simultaneously. So we studied the combined acidification and profile control system indoors. The supporting acid solution system was one-step acid solution system

and its performance such as retarding speed

inhibiting secondary precipitation

dissolution and compatibility were evaluated experimentally. And then

we obtained that the permeability recovery was good after single core acidizing. The main agent of profile control agent system is anionic polymer

and its acid resistance and core plugging ability were evaluated. A double-core clamping flow test device was used to simulate the non-homogeneous layerss and analyze the influence of the injection sequence of the profile control and acidizing on the combined treatment effect. The simulation results showed that the acidification effect after profile adjustment was obvious

the permeability improvement ratio of low permeability core was 1.52

the permeability improvement ratio of high permeability core was blocked

and the permeability improvement ratio was 0.29. The goal of starting low permeability core by reducing the permeability difference between layers was realized.