The invention discloses a temperature-resistant, salt-resistant, high-temperature self-crosslinking in-situ polymerized water blocking gel, which mainly consists of a main agent, a crosslinking agent and brine, and its
mass percentage is: 4-6% of the main agent, 1% of the crosslinking agent ~2%, the rest is brine; the main agent is composed of
monomer A and
monomer B,
monomer A is
acrylamide, and monomer B is an ester; the crosslinking agent is
formaldehyde, phenolic resin,
resorcinol, six Methylenetetramine,
paraformaldehyde, polyethyleneimine, one, two or a mixture of two or more. The present invention can spontaneously cross-link and polymerize under high temperature conditions without adding an initiator, and the gelation time at 120°C can be controlled within 2 to 28 hours. It can be directly prepared with high-
salinity water, and the
gel strength can reach the visual code I level.
Syneresis did not occur for 90 days. The invention has the advantages of low initial
viscosity, few components, good instant
solubility, good pumping performance, high plugging strength, good hot-salt stability, and low cost, and has broad application in profile control and water plugging of high-temperature and high-salt reservoirs. Application prospect.