Thermoreversible Polymer Gels for Enhanced Oil Recovery

Thermally reversible polymeric gel forming systems based on polymer solutions with the lower critical temperature of dissolution - cellulose ethers - were developed to increase the oil recovery from highly heterogeneous strata. The reversible phase transition solution-gel occurs due to the thermal energy of a stratum or injected heat transfer agent. Temperature and time of gelatinization can be controlled by adding electrolytes and non-electrolytes. Laboratory studies of the gelatinization kinetics, rheological and filtration characteristics in the system cellulose ethers-aqueous phase-oil are presented. Results of experimental-industrial tests of the technologies of oil recovery enhancement involving thermally reversible polymeric gels for limitation of water inflow, increase in stratum coverage degree during flooding and thermal steam formation treatment are presented. Technologies are economically profitable and ecologically safe; the payback period is 5-9 months. The products of large-scale industrial production are used as reagents.