2023 Volume 79 Issue 25 Article ID: 23-25019
This paper presents bench-scale experiment results of a new coagulant dosage control for water purification processes. The developed new control scheme has a cascade structure where an inner loop Proportional-Integral controller works to determine coagulant dosing rate by using a flocculation image sensor and an outer loop set-point optimizer calculates the set-point of the inner loop controller using the extremum seeking (ES) technique. The image sensor measures the electrophoretic velocity (EV), which is an index of flocculation process performance, and its set-point is optimized by using a performance index consisting of a total operational cost and a treated water quality constraint. Several bench-scale experiment results show that the developed controller works well for both the case that the treated water quality constraint is active and the case that the optimal point is an interior point of the feasible region.
