The Study And Realization Of Electric Automatic Controlling System In City Wastewater Treatment

With the rapid development of cities,the environment becomes more and more important. Wastewater is one of the major factors that pollute the environment.The automatic controlling system of wastewater treatment in China is not very advanced.The cost of wastewater is high.The water qualities of the treated wastewater are unstable.So how to solve the problems is very significative to our country.The paper based on the reconstruction of Chongqing Chengnan Wastewater Treatment Factory.A automatic controlling system was set up which adopt industrial Ethernet.The major work includes three aspects.The design of electrical control includes starting and stopping the equipment,state indication,trouble treatment,system signal collection.The exploitation of Lower Computer includes plotting the controlling station,writing the controlling program of PLC,optimizing the controlling program by interior files of PLC,counting the amount of treated wastewater and running time of the pumps.The exploitation of Upper Computer includes the designing of the controlling map,setting up the database of operation and real time curve of water quality,accomplishing the system alarm,building and printing the report forms of the factory.The system has been working stably in the past year.The water quality of the treated wastewater is very good and the cost of the treatmentg has been lowed.