The Feasibility Of Using The Waste Liquid Containing Polymer Profile Control Research

With the promotion and application of tertiary oil recovery, there are more and more difficult injection Wells. To inject difficult well regular wash well can act as efficient solution plugging effect, but wash well will produce a lot of washing well fluid flowback. Wash well flowback fluid composition is complicated, which contains a lot of polymer, solid impurities, such as metal ions and bacteria, once in the sewage treatment system will seriously affect the normal operation of the system. And polymer cannot be isolated from the curing and pollute the environment, buried deep on soil pollution and influence, this kind of treatment is impossible to eliminate the pollution to the environment, but also need a lot of costs.In this paper the well-flushing fluid flowback preparation a certain concentration of polymer solution, adding to the solution, crosslinking agent and stabilizer formation can be used in the oil field profile control system of crosslinking. By investigating different formula form gel system of gel time and gel strength, optimizing the final use of polymer concentration, polymer concentration ratio and stabilizer. A laboratory test of optimization system, analysis of fluid flow characteristics and profile control agent profile control effect.The research results show that wash well produce a lot of washing well although flowback fluid containing a certain concentration of polymer, but directly after joining crosslinking agent could not form gel system. Will waste liquid preparation, after a certain concentration of polymer solution can solution and citric acid chrome crosslinking agent of crosslinking reaction. System of polymer concentration, polymer cross ratio, stabilizer concentration will affect the gel effect of gel system, based on the actual and the cost consideration, determine the formula containing polyethylene waste liquid dispensing profile control system: polymer concentration of 1400 mg/L, delivery ratio of 30:1, stabilizer concentration of 800 mg/L. Raises the profile control system flow characteristic experiment: the system can be injected into the minimum core permeability for 600×10-3μm2; The biggest increase injection 0.1 pv of gel system recovery. The study found that residual polymer and suspended solids in waste liquid containing poly sealing characteristics of the gel system has certain positive effect.