Device for controlling dissolved oxygen concentration of aeration tank, device for controlling temperature of aeration tank, device for controlling flow rate of raw water for homogeneous-flow liquid surface, and wastewater treatment equipment used in activated sludge process

摘要

In wastewater treatment equipment utilizing the activated sludge process in a comprehensive wastewater treatment plant and a sewage treatment plant of chemical factories or the like, wastewater is treated in a stabilized manner controlled so as to prevent excessive or insufficient feed of oxygen and to keep the concentration of dissolved oxygen in the tank constant by receiving a signal from a dissolved oxygen analyzer (5) by means of a predictive-PID control unit (11), predicting the behavior of the dissolved oxygen concentration by using the control data in the past and a dynamic behavior model for the controlled system, comparing the predicted value with the target value of the dissolved oxygen concentration, and adjusting the feed rate of oxygen to reduce the deviation.