Achieving Partial Nitritation by Treating Sludge With Free Nitrous Acid: The Potential Role of Quorum Sensing

Abstract

Partial nitritation is increasingly regarded as a promising biological nitrogen removal process owing to lower energy consumption and better nitrogen removal performance compared to the traditional nitrification process, especially for the treatment of low carbon wastewater. Regulating microbial community structure and function in sewage treatment systems, which are mainly determined by quorum sensing (QS), by free nitrous acid (FNA) to establish a partial nitritation process is an efficient and stable method. Plenty of research papers reported that QS systems ubiquitously existed in ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB), and various novel nitrogen removal processes based on partial nitritation were successfully established using FNA. Although the probability that partial nitritation process might be achieved by the regulation of FNA on microbial community structure and function through the QS system was widely recognized and discussed, the potential role of QS in partial nitritation achievement by FNA and the regulation mechanism of FNA on QS system have not been reviewed. This article systematically reviewed the potential role of QS in the establishment of partial nitritation using FNA to regulate activated sludge flora based on the summary and analysis of the published literature for the first time, and future research directions were also proposed.

Concept development of a mainstream deammonification and comparison with conventional process in terms of energy, performance and economical construction perspectives

“…Since the last decades, there have been many studies conducted on the determination of optimal conditions for deammonification, the effect of reactor technologies such as moving bed biofilm reactor (MBBR) and configurations such as integrated fixed-film activated sludge (IFAS), the impact of different biofilm carriers and additives such as salts and polymers for the process stability, the identification of the diversity and distribution of involved microorganisms and examination of their growth conditions ( Liu et al, 2021 ; Feng et al, 2022 ; Jiang et al, 2022 ; Ladipo-Obasa et al, 2022 ; Schoepflin et al, 2022 ; Zhang et al, 2022 ). So far, most of the studies have been carried out on a laboratory scale with artificial wastewater.…”