Coagulant Dosing Process Control Technology

Coagulation is an economic and simple water treatment technology in improving the water quality treatment efficiency at home and abroad. Coagulation is one of the key issues of dosage control. Accurate dosage of coagulant is the prerequisite of obtaining good coagulation effect and economic benefits. Many domestic water plant coagulant dosage results are not satisfactory, because in actual treatment process, due to the fluctuation in water quality and quantity, how to control changes in water quality for the best coagulant dosage, has long been the water supply industry general concern but a serious problem.In the actual treatment process, The dosing process of coagulant has the characteristics of non-linear, long time delay, multi-variable, etc. Therefore, the research of control method for the dosing of coagulant has great significance.Through analyzing the factors of coagulation and the factors affecting the coagulation process, the factors affecting the coagulation dosage are found out. Main factors, like temperature, quantity of raw water and turbidity of raw water are found out through analyzing the actual situations. Through treatment of temperature zone and raw water quantity, the turbidity of raw water is viewed as the only factor which will affect the dosage, and numerical model of raw water turbidity and dosage amount is established. Through comparing the actual data, we found out that the established numerical model is effective. However, its precision is not too very high due to the special conditions while the establishment of this model. With the development of neural network, the BP neural network is applied in the control of coagulant dosage to realize precise control of the dosage. According to the simulation of actual data, a good effect is obtained. Thus the accurate control of coagulant dosage is realized and the production cost is reduced.An automatic control method suitable for the coagulant dosing in waterworks is developed through studying the control method of coagulant dosage. This method is very suitable for the current automatic level of medium- and small-sized waterworks of China and has wide application prospects. .