An Adaptive Fuzzy Logic Control Method for Froth Velocity in the Flotation Process

• Published in: IFAC-PapersOnLine 2024, Vol.58 (22), p.7-12
• Main Authors: Yang, Yang, Gui, Weihua, Wang, Xiaoli, Qin, Liyang, Xu, Honglei, Chen, Zhiwen
• Format: Article
• Language: English
• Subjects: adaptive; flotation process; froth velocity; fuzzy logic control
• ISSN: 2405-8963; 2405-8963
• DOI: 10.1016/j.ifacol.2024.09.282

In the flotation process, too high or too low froth velocity can lead to a reduction in the recovery of useful minerals. However, it is difficult to achieve stable control of froth velocity due to complex process characteristics and fluctuating working conditions. Uncertain feed conditions (feed flow rate, feed grade, and feed concentration) can cause large changes in the desired froth velocity and other uncertain conditions, which affect the accurate evaluation of the velocity state for feedback control. In this paper, an adaptive fuzzy logic control method for froth velocity (AFLC-FV) in the flotation process is proposed. In the method, an adaptive fuzzy quantization function with a dead zone is designed and used instead of the constant fuzzy quantization factor in the fuzzification procedure. Thus, the dynamic real domain of the velocity error can be mapped to a fixed standard fuzzy domain. Meanwhile, the width of the dead zone is adaptively adjusted according to froth mobility to improve steady-state performance. In addition, the velocity trend is extracted and used as an input variable to the controller together with the velocity error. The application results show that, compared with manual control, the AFLC-FV significantly enhances the control accuracy and stability under different ranges of velocity set-points, and effectively improves the mineral recovery by 0.18%.