Application of SBR-MFC process in wastewater treatment at high-altitude areas of Xizang: research on MPC voltage boosting and stabilization strategies

The contradiction between the demand for plateau wastewater treatment and high energy consumption has become increasingly prominent, necessitating the development of efficient microbial fuel cells and the exploration of microbial communities adapted to high-altitude conditions. Based on an SBR-MFC platform established in the Qinghai-Xizang Plateau environment, this study addresses issues such as low output voltage, strong output randomness, and instability in series/parallel systems. For a high-gain DC/DC boost converter, a dual closed-loop model predictive control strategy is proposed. A closed-loop control function is constructed, taking the output voltage and excitation inductor current as controlled variables. By feeding back and correcting prediction and real-time detection errors, the corresponding operating mode is selected to achieve dynamic regulation of the duty cycle. Using simulation software, analyses were conducted for MFC and MFCs output conditions of 3.3 V and 4.8 V. Parameters such as overshoot, operating duration, steady-state proportion, and efficiency under different schemes were compared to validate the effectiveness of the control strategy. Additionally, the platform achieved removal rates of 57.88% for COD, 65.21% for TN, and 30.36% for TP. Microbial community analysis indicated a succession toward electroactive genera such as Clostridium and Pseudomonas, contributing to the exploration of dominant microbial populations in MFCs applied in the Qinghai-Xizang Plateau region.