Study and Field Application of Profile Control Agent in High Temperature and High Salinity Reservoir

Abstract

Abstract Polymer gel is not suitable for profile control in high temperature and high salinity reservoir. In order to solve the problem above, a good inorganic profile control agent (Na2O·mSiO2) used in high temperature and high salinity reservoir is studied in this paper. The thermal sensitivity, salt sensitivity of sodium silicate and their influence factors in high temperature and high salinity are investigated. The blocking ability and oil displacement ability of sodium silicate in high temperature and high salinity are also investigated through physical simulation experiments. The results show that sodium silicate in high temperature and high salinity can self-generate white precipitation which can effectively block high permeability zone and or thief zone and expand sweep volume. The precipitation mass is related to modulus, temperature and aging time in high temperature; after meeting brine water, sodium silicate can also generate white precipitation and the precipitation mass is associated with modulus, salinity and temperature. Sand pack experiments indicate that sodium silicate in high temperature and high salinity has good blocking and oil displacement effect, which can further enhance oil recovery. Field application results also confirm that sodium silicate is a good inorganic profile control agent in high temperature and high salinity reservoir.