Mud and sand blockage prevention and control technology suitable for water injection of loose sandstone reservoir

• Main Authors: ZHANG ZHIHAO, YU DUNYUAN, WANG ZHIZUN, WANG FUHUA, ZHU HAITAO, WANG LUYI, ZHANG WEIDONG, SUN ZEZHUANG
• Format: Patent
• Language: Chinese; English
• Published: 08.06.2021
• Subjects: ADHESIVES; CHEMISTRY; DYES; EARTH DRILLING; EARTH DRILLING, e.g. DEEP DRILLING; FIXED CONSTRUCTIONS; MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FORELSEWHERE; METALLURGY; MINING; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR ASLURRY OF MINERALS FROM WELLS; PAINTS; POLISHES

The invention relates to a mud and sand blockage prevention and control technology suitable for water injection of a loose sandstone reservoir. According to the technical scheme, before water is injected into a stratum through an injection well, a salt water slug is injected into the stratum firstly, then a wetting reversal agent solution slug is injected, then a clay stabilizer solution slug is injected, and finally water injection is started. Salt comprises inorganic salt and organic salt. A wetting reversal agent is mainly a nonionic organic amine surfactant, a cationic surfactant and the like. A clay stabilizer is a clay particle migration prevention agent and is mainly an organic nonionic polymer, an organic cationic polymer and the like. The mud and sand blockage prevention and control technology has the beneficial effects that the technological operation is simple, hydration expansion and hydration dispersion of clay in the loose sandstone stratum can be effectively inhibited in the water injection pro