The Research of JA Composite Acidizing Plugging Removal System: Formulation Optimization and Performance Evaluation

Abstract

According to the abnormal pressure and poor water absorption of the JA reservoir, JA complex acidizing plugging removal system was proposed to improve oil production. The main acid of JA composite acid system was screened by acid sensitivity evaluation experiments. According to the corrosion evaluation experiment, the optimal concentration of HCL, HF and organic mixed acid (mixed by organic acid A and B in 1:1) in JA composite acid system is 15%, 3 % and 10%, respectively. In order to ensure the compatibility of JA composite acid, both preflush and overflush acid were used the mixed solution of 15% HCL and 3% HF. The evaluation of corrosion resistance indicated that the corrosion rate of JA composite acid could be reduced from 11.92 to 1.92 g/(m2•h) when the corrosion inhibitor H was loaded at the concentration of 1%. While 1% ferric ion stabilizer (JYS-1) was added, the stabilization efficiency of JA composite acid could reach 97.20%. The optimal formulation of JA composite acid is 15%HCL + 3%HF + 10% organic mixed acid + 1% corrosion inhibitor H + 1% JYS-1.