Advances in aerobic granular sludge stabilization in wastewater
Xurundong Kan, Bofan Ji, Jianqiang Zhang, Zaiqiong Liu, Yiren Xu, Lijuan Zhao, Bingfei Shi, Jingwei Pu, Zhiying Zhang
Abstract
This study provides a comprehensive overview of the advancements made in the research concerning the stability of aerobic granular sludge, and succinctly outlines the development mechanisms of aerobic granular sludge, encompassing the "filamentous bacteria theory" and the "extracellular polymer theory", "selective pressure driven hypothesis", and "self coagulation hypothesis"; The primary elements influencing the stability of aerobic granular sludge include temperature, pH levels, the rate of organic loading, and concentrations of ammonia nitrogen, dissolved oxygen and particle size, satiety hunger period, hydraulic shear force, sludge age and toxic and harmful substances; It is discussed in detail that measures such as inhibiting filamentous bulking, promoting the secretion of extracellular polymers, enhancing the growth of slow-growing microorganisms and fortifying the central structure of granules can improve the stability of aerobic granular sludge. It is suggested that future studies should prioritize exploring the formation mechanisms and functional microbial communities associated with aerobic granular sludge. Such investigations will lay the groundwork for its broader industrial applications.