A method for adjusting the ph - value of the drinking water in a drinking water processing plant

摘要

The pH value of potable water in a water treatment plant is adjusted by controlled automatic addition of a treatment chemical, to alter the acidity. The measured mains water throughput of the plant is used in the treatment algorithm together with a second variable, x2, a chemical concentration value. The set point is adjusted on the basis of a regular water analysis. Also claimed is a process where the pH control is achieved by calculating a value for dosed chemical quantity w1 from a mathematical model of the control loop (20) and the measured water throughput z1; and the quantity dosed is controlled from the target dose quantity w1 as target value in conjunction with a measured value of the dosed throughput amount x1.