A Study On Acidizing Plugging Removal System Of Chang-6Reservoir

In Wu410area and BaoZiWan area,the Chang-6reservoir have problems of low Permeability and low hygroscope capacity. With the techniques of x-ray diffraction analysis,SEM,sensitivity tests,the thesis make a throught research, on Physical properties of Chang-6reservoir in Wu410well region and Chang-6reservoir in BaoZiWan well region.This work,on the basis of Dissolution experiment and Simulation acidification flow experiment,has summarized the Acid formula for Chang-6reservoir.The conclusions go as follow:(1) The content of Quartz, Feldspar, Clay minerals, Chlorite, Kaolinite of Chang-6reservoir in BaoZiWan area are respectively between29%～36%,44%～53%,12%～17%,4%～8%,4%～5%. And the content of Quartz, Feldspa, Clay minerals, Chlorite, Kaolinite of Chang-6reservoir in Wu410area are respectively between19%-28%,44%～53%,12%～17%,4%～8%,4%～5%. The porosity of Chang-6reservoir in BaoZiWan well region is between15%-19%. The average permeability is0.39×10-3μm2.The porosity of Chang-6reservoir in Wu410well region is between16%～20%. The average permeability is0.28×10-3μm2. Both of BaoZiWan oil region and Wu410oil region were low permeability reservoir. The content of clay mineral is higher.(2) The acid system using HCl+HCOOH+additive as ahead acid, HC1+HF+HCOOH+additive as the main acid and HCl+HCOOH+additive as post-acid was used for the acidic experiment on the study of the servoir of Chang-6reservoir reservoir in Wu410area.(3) The acid system using HCOOH+HCOONa+additive as ahead acid,HCl+HBF4+additive as the main acid and HCOOH+HCOONa+additive as post-acid was used for the acidic experiment on the study of the servoir of Chang-6reservoir reservoir in BaoZiWan area. It is turned out that this acid system can improve the core permeability efficiently and can fufill the goal of acidification.