Study On Auto-adding Of Slime Water System Base On PLC-fuzzy Control

Along With the increasing enhance of closed water circuit for coal preparation plant and environmental protection requirement, flocculants is a necessary auxiliary measure in slime water treatment. And then it's necessary to select the flocculants for melting and adding equipment. Since domestic dispensing and adding facility is just in the developing stage now, and import equipment is dear; at present most of domestic coal separating plants depend on manual melting and adding agent. Therefore, according to our country actual conditions of coal slime water treatment,it's essential to study and develop the prepared and added flocculants automatically device.The paper introduces the developing situation of the auto adding control technique. By analyzing and studying the checking link, the controlling mode and control strategy on automatically adding system, in connection with some features such as long time lag,nonlinearity and modeling difficulties, it puts toward the fuzzy control method of autoadding process in slime water-treamt. a fuzzy control method on the basis of PLC and discoursed principle and structure of the fuzzy controller and designs a fuzzy controller of two inputs and one output to control on the parameters of flux online. the design of fuzzy contorller is consisted by fuzzification of inputs,making fuzzy control rules and defuzzification. The design of fuzzy controller is realized by PLC. the off-line calculation of fuzzy control table is realized by MATLAB. It designs the plan of adding system. The system is consisted by electrical machinery,quantitative pump and transducer. The sensor of sedimental speed checks sedimental speed's deviation and the differential element checks the variance ratio of sedimental speed. The result is feedbacked by PLC. And then frequency conversion device is fuzzily controlled by the fuzzy computation. Finally, the closed time control system is built. Taking the slime water of some coal seperating plant as the example, choicing plan of the best flocculants is introduced. Under the some consistency the sedimental and clarifying characters are discussed. The adding methods of flocculants is set.The fuzzy control is combined with PLC to overcome the disadvantage of traditional controlling equipment, to competely show the advantage of PLC neat control, easy programming, strong suitability and to raise. the controlling precision. flocculants scientifically and reasonably added on line is done. The electrical machinery and the pump running below in fundamental frequency in majority time is ensured, and the abrasion of the pump and the system noise is effectively can reduce, and the service life is extended, and the reliability of the system is enhanced, and the electronic power is saved. Meanwhile, the speed of response and the stable precision of the system is also raised. The system provides the important reference value for the slime water treatment work of coal preparation plant in China.