Abstract:
Plateau regions have unique environmental features such as low air pressure, low oxygen, low temperatures, and strong UV radiation, which significantly affect the performance of wastewater treatment systems. Membrane bioreactors (MBRs) are considered an important technology for wastewater treatment and water reuse in high-altitude areas due to their advantages of excellent effluent quality, higsludge concentration, and small footprint. However, the plateau environment significantly impacts MBR operational stability and membrane fouling development by altering oxygen transfer, microbial metabolism, and sludge characteristics, making traditional design theories and operational parameters developed in plains not directly applicable to high-altitude regions. This paper systematically summarizes the research progress on changes in MBR performance, membrane fouling mechanisms, and adaptive control strategies in high-altitude areas, focusing on the plateau environment as the driving mechanism. It highlights oxygen transfer limitations driven by low air pressure, microbial responses and reconstruction of nitrogen and phosphorus removal pathways under low-temperature and low-oxygen conditions, and clarifies the key role of extracellular polymeric substances (EPS) and soluble microbial products (SMP) in membrane fouling. On this basis, a theoretical framework of "plateau environment—microbial stress—EPS/SMP release—membrane fouling evolution" is established. A low-pressure-driven membrane fouling evolution mechanism was proposed, in which low pressure and low temperature limit oxygen transfer, induce microbial metabolic stress, stimulate excessive EPS/SMP secretion, and consequently accelerate membrane fouling development.The paper further summarizes membrane fouling control strategies, including plateau-adaptive membrane materials, precise oxygen supply, micro-electric field enhancement, and intelligent operation, and discusses the future development of plateau MBRs. This study provides theoretical guidance and technical support for optimizing wastewater treatment system design, low-carbon operation, and intelligent management in high-altitude areas.