CHEMICAL INJECTION CONTROL METHOD AND CHEMICAL INJECTION CONTROLLER

摘要

A chemical injection controller (1) corrects the chemical injection percentage based on the difference between the measurement of the water quality index of treated water by operating a chemical injection pump based on a preset chemical injection percentage and the target value of the water quality index, and calculates the optimal chemical injection percentage. Next, the optimal chemical injection percentage is set as the target variable, and at least one water quality index of raw water is set as the control variable, then multiple regression analysis is conducted to derive the equation for calculating the basic chemical injection percentage corresponding to the water quality index. Next, the measured value of the water quality index of raw water is given to the calculation equation to calculate the basic chemical injection percentage corresponding to the water quality index. Next, the basic chemical injection percentage is corrected based on the measured value of the water quality index of the treated water by operating the chemical injection pump based on the basic chemical injection percentage, and a new chemical injection percentage is calculated and output as the controllable factor of the chemical injection pump, and given to the calculation of the optimal chemical injection percentage.