ABSTRACT
In order to solve the problems of poor acidizing and increasing injection effect, not obvious depressurization effect and short effective period of high pressure water injection wells, polyhydroacid repetitive acidizing process was proposed. According to the geological characteristics and reservoir physical properties of Xi10 block, the reasonable concentration of additives in the polyhydroacid system is optimized, and then the polyhydroacid acid system with repeated acidification is obtained. Stimpro software was used to simulate the reasonable acid quantity and displacement of repetitive acidification. The results showed that HB-1 had buffering effect, and the higher the concentration, the better the buffering effect. The core flow experiment shows that the core permeability increases significantly after repeated acidification compared with that after one acidification. When the displacement is 1.5 m3/min and the acid content is 80 m3, the optimal effective action distance is 2.5 m.
