In the process of tertiary recovery polymer flooding of industrial polymer displacement of oil, the mother solution of polymer that is preliminarily dispersed and wetted is firstly delivered to the maturation tank for further agitation and maturation. The agitating speed of agitator for large tank is generally from 40 to 50RPM, which is a fixed speed. The conventional maturation process is that each tank (150m3) of mother solution is maturated for two hours (adjustable) during process of agitation at a fixed rate of 50RPM. The agitator for large tank was originally started up by an autotransformer. Since the agitator is a load of large inertia, which creates large starting impact and fails to realize real soft start and soft shutdown and the reduction gearbox is damaged quickly.

The rotation and agitation of agitator blades in the mother solution will surely lead to shear to mother solution and decrease the viscosity of mother solution and lower the efficiency of polymer displacement of oil. As a result, the retention of viscosity is a very important index for measuring the quality of equipment or process.

Based on the existing conventional process, we carried out comparison test and analysis on agitating speed and agitating time of agitator, and corresponding viscosity of mother solution, and got to the bottom of progress process of maturation of polymer. We developed Series ZNJB-01 intelligent curve agitation tracking controller, which effectively handles the issue of matching between the agitating speed and the time of maturation of mother solution of polymer with different molecular weight from different suppliers.

Under automatic control of the intelligent control program provided to the control cabinet, the agitator for maturation of mother solution of polymer operates as per the given curve in accordance with the set speed-time curve, which can decrease the shear rate of mother solution so as to make the matured mother solution at slight agitation state and dramatically reduce the settlement of mother solution at the bottom of tank, realize the soft start and soft shutdown of agitator, reduce the impact on mechanical system, improve the effect of maturation, prolong the service life of agitator, decrease the degradation of viscosity of mother solution of polymer, and decrease the electricity consumption, saving electricity by 20% to 30%. In addition, the temperature rise, noise and vibration of motor can also be decreased to improve the operating environment.

The control cabinet is provided with complete functions and perfect protections, which is the most ideal control system for maturation and agitation of the mother solution of polymer and can generate good economic benefits. The controller can not only be used for maturation and agitation of polymer but also be widely applied to other occasions where variable-speed agitation is required.