In-situ sludge reduction based on Mn^(2+)-catalytic ozonation conditioning:Feasibility study and microbial mechanisms  

作　　者：Haozhe Huang Tingting Wei Hui Wang Bing Xue Sisi Chen Xiankai Wang Haibin Wu Bin Dong Zuxin Xu 

机构地区：[1]College of Environmental Science and Engineering,Tongji University,Shanghai 200092,China [2]YANGTZE Eco-Environment Engineering Research Center,China Three Gorges Corporation,Beijing 100038,China

出　　处：《Journal of Environmental Sciences》2024年第1期185-197,共13页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Nos. 52192684 and 52270136);the National Key Research and Development Project (No. 2020YFC1908704);China Three Gorges Corporation (No. 202003166)。

摘　　要：To improve the sludge conditioning efficiency without increasing the ozone dose,an in-situ sludge reduction process based on Mn^(2+)-catalytic ozonation conditioning was proposed.Using ozone conditioning alone as a control,a lab-scale sequencing batch reactor coupled with ozonated sludge recycle was evaluated for its operating performance at an ozone dose of 75 mg O_(3)/g VSS and 1.5 mmol/L Mn^(2+)addition.The results showed a 39.4%reduction in MLSS and an observed sludge yield of 0.236 kg MLSS/kg COD for the O_(3)+Mn^(2+)group compared to the O_(3)group (15.3%and 0.292 kg MLSS/kg COD),accompanied by better COD,NH_(4)^(+)-N,TN and TP removal,improved effluent SS and limited impact on excess sludge properties.Subsequently,activity tests,BIOLOG ECO microplates and 16S rRNA sequencing were applied to elucidate the changing mechanisms of Mn^(2+)-catalytic ozonation related to microbial action:(1) Dehydrogenase activity reached a higher peak.(2) Microbial utilization of total carbon sources had an elevated effect,up to approximately 18%,and metabolic levels of six carbon sources were also increased,especially for sugars and amino acids most pronounced.(3) The abundance of Defluviicoccus under the phylum Proteobacteria was enhanced to 12.0%and dominated in the sludge,they had strong hydrolytic activity and metabolic capacity.Denitrifying bacteria of the genus Ferruginibacter also showed an abundance of 7.6%,they contributed to the solubilization and reduction of sludge biomass.These results could guide researchers to further reduce ozonation conditioning costs,improve sludge management and provide theoretical support.

关 键 词：Activated sludge In-situ reduction Catalytic ozonation conditioning Dehydrogenase activity Carbon source utilization Microbial community 

分 类 号：X703[环境科学与工程—环境工程]