The Control Technology On Treatment Of Cr-containing Effluent In Basic Condition

This dissertation mainly concerns a deep study and exploration on treatment of Cr-containing effluent,and comes up with a kind of simple and practical control technology which can be applied in the location.This paper accomplishes the following researches: Firstly, the paper analyzes the characteristics of pH and ORP by means of lots of experiments, which show that both pH and ORP are nonlinear and have large lag. In addition, ORP is indefinite. In the mean-time, there is coupling function between the pH and ORP. After that, the important point and pinch point at the control is pointed. Secondly, a kind of leading control method on the basis of energy containing in system, which combined the demerits of PID control and neural network control, is presented according to the large hysteresis characteristics of the pH and ORP. Furthermore, linearization of pH is actualized in this paper.Thirdly, considering the coupling between the pH and ORP, a kind of simple and effective decoupling control method is proposed on the principle of chemical reaction. Fourthly, the simulation program is complied in the Turbo C language, displaying the emulated outcome in static or dynamic states. In the end, the real-time simulation experiment on the physical model has been accomplished in the laboratory and the control method has been applied in the industrial field. The results state that the control device is of simple construction, easy accomplishing, perfect control properties and strong ability to resist interference.