Efficient pollutant removal from deodorization wastewater during sludge composting using MBR-CANON process. Issue 6 (December 2022) - Ma, Bingbing
Abstract: Sludge composting is one of the most economical and effective sludge disposal method at present. However, the composting process releases massive odorous gas, and the gas removal process produces a large amount of deodorizing wastewater with low C/N ratio (named as composting wastewater). In this study, completely autotrophic nitrogen removal over nitrite (CANON) process was adopted for treating composting wastewater. After treated, the ammonia decreased to 0–5 mg L −1, and the total nitrogen removal achieved to 0.200 kg m −3 d −1 . Although the introduction of composting wastewater reduced the hydroxylamine oxidoreductase enzyme activity, heme-c, and hzo gene, all of them could be recovered. Microorganisms secreted more extracellular polymeric substances to counteract the cell-damage caused by harmful substances. Chloroflexi, Proteobacteria, and Planctomycetota were detected as the dominant phyla in the system, and the relative abundances of Candidatus_Kuenenia and Nitrosomonas reached 19.8% and 2.8%, respectively. CANON process could be used for treating composting wastewater. Graphical Abstract: ga1 Highlights: Nitrogen and COD removal from composting wastewater was achieved simultaneously. The nitrogen removal from composting wastewater reached 0.200 kg·m −3 ·d −1 . AAOB can resist the toxic substances by secreting more EPS. CANON process was feasible for treating composting wastewater.