Acid production control using fuzzy logic

The ability to maintain an adequate inventory of cooking acid is critical in the sulfite pulping process. Moreover, the amount of combined SO2 must be maintained to prevent variations in the acid concentration. Historically, acid production rate control has been primarily a manual operation based on operator experience based on the results of acid concentration tests. Changing the acid production rate means adjusting the flow of each constituent in such a way as to keep the inventory at an acceptable level while maintaining the proper ratio of constituents. The objective of this work is to present a two dimensional space fuzzy logic control scheme to control acid production while minimizing variations in acid concentration. The algorithm will be presented along with the actual results.