This invention provides a deep moderating and displacement
system suitable for fractured reservoirs, its preparation method, and its application. The moderating and displacement
system comprises the following raw materials in parts by weight: 0.2-1 parts of partially hydrolyzed
polyacrylamide (HPAM), 0.1-0.6 parts of polyethyleneimine (PEI), 0.2-0.4 parts of
silane-modified micron-sized inorganic fibers, 0.1-0.8 parts of encapsulated
citric acid, 0.02-0.2 parts of heat stabilizer, 0.02-0.1 parts of
metal ion complexing agent, and 196.9-199.36 parts of water. The moderating and displacement
system of this invention has low initial
viscosity, small
injection pressure gradient, strong shear
recovery ability, significant deep plugging effect, and excellent long-term
thermal stability. Furthermore, it can be adjusted according to the target reservoir temperature and the dominant fracture aperture, achieving effective
adaptation to fractured reservoirs with different apertures.