Optimization and Application of Large-Scale Acidification and Multi-Stage Injection Technology

Abstract

With the increasing demand for clean energy in China, the development of natural gas is constantly intensifying, and deep carbonate reservoirs are important production areas for natural gas. In recent years, large-scale acid fracturing has become a major trend in the transformation of carbonate reservoirs, with a large potential market in the acid fracturing industry. At present, good results have been achieved in blocks such as Yuanba, Daqing, and Pengzhou. At present, the large-scale deep acid fracturing technology for ultra deep acid gas wells at home and abroad is based on the "high-temperature and high corrosion inhibition gel+high-temperature diversion" acid system and the "multi-stage alternating injection+soft and hard material composite temporary plugging" process. This year, large-scale composite acid fracturing can achieve long-distance and deep penetration transformation of reef and beach reservoirs, providing technical support for the production capacity construction of major marine oil and gas reservoirs around the world. Currently, through the self-developed online acid supply system, multi-stage continuous acidification construction with a scale of over 2000m³ has been achieved, realizing various process technologies such as no reduction in displacement and temporary plugging without stopping pumps during the acidification construction process.