Structure Design And Characteristics Study Of The Static Mixer For Mixing Polymer In EOR

In oilfield tertiary recovery, static mixer will be used to mix polyacrylamide water solution(PAM) and water, and then pourd them into underground. In industrial production, in order to improve oil displacement effect,when the polyacrylamide solution through the static mixer, its viscosity reduction rate should be less than 2%.But present field used static mixer is unable to satisfy the request, therefore, special static mixers are needed to insure that the viscosity decreasing ratio of PAM water solution is less than 2%.Based on the previous studies, this paper designed a kind of special static mixer for mixing polymer, and carried on the optimization of the static mixer's structure through the experiment and numerically simulation.First, the degradation characteristics of PAM non-Newtonian fluid in static mixers were studied. The effects of flow rate and static mixer type on the viscosity decreasing ratio of 0.5%(wt)PAM water solution were investigated. The relations between pressure drop and flow rate, blade angle, length of inner pipe were obtained.Next, the mixing characteristics of PAM non-Newtonian fluid in static mixers were studied. The effects of the rate of hole, hole location, hole size, the number of openings on the pipe were investigated. The best structure that meet the requirement of industry for the degradation rate and the mixing effect were optimized according to the experiment.At last, using FLUENT software, the flow and concentration fields in the static mixer were obtained and the static mixer mixing mechanism was analysised.The above experiment and the numerical simulation research work has provided the basis for the later further research.