Analogue and microprocessor control of an electrochemical waste-acid treatment process

Electrochemical cells used for effluent treatment may, in many cases, require automatic control to handle load changes in the waste discharge. Results are presented for the automatic neutralization of a simulated chloralkali waste-acid stream using hydroxyl generated by an electrochemical cell operating under current control. The performance of a simple analogue PID controller is compared with that of a modern microprocessor-based adaptive controller.