Experimental and modeling investigations on the unexpected hydrogen sulfide rebound in a sewer receiving nitrate addition: Mechanism and solution  

作　　者：Zhensheng Liang Dongping Wu Guibiao Li Jianliang Sun Feng Jiang Yu Li 

机构地区：[1]School of Environment,Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Theoretical Chemistry of Environment,South China Normal University,Guangzhou 510006,China [2]Guangdong Provincial Key Lab of Environmental Pollution Control and Redemidation Technology,School of Environmental Science&Engineering,Sun Yat-sen University,Guangzhou 510275,China

出　　处：《Journal of Environmental Sciences》2023年第3期630-640,共11页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (No. 51638005);the Fundamental Research Funds for the Central Universities (No. 20lgzd24);the Guangdong Basic and Applied Basic Research of the Joint Regional Fund (No. 2019A1515110569);Guangdong Provincial International Joint Research Center on Urban Water Management and Treatment (No. 2021A0505020010)。

摘　　要：Biogenic hydrogen sulfide is an odorous, toxic and corrosive gas released from sewage in sewers. To control sulfide generation and emission, nitrate is extensively applied in sewer systems for decades. However, the unexpected sulfide rebound after nitrate addition is being questioned in recent studies. Possible reasons for the sulfide rebounds have been studied,but the mechanism is still unclear, so the countermeasure is not yet proposed. In this study, a lab-scale sewer system was developed for investigating the unexpected sulfide rebounds via the traditional strategy of nitrate addition during 195-days of operation. It was observed that the sulfide pollution was even severe in a sewer receiving nitrate addition. The mechanism for the sulfide rebound can be differentiated into short-term and long-term effects based on the dominant contribution. The accumulation of intermediate elemental sulfur in biofilm resulted in a rapid sulfide rebound via the high-rate sulfur reduction after the depletion of nitrate in a short period. The presence of nitrate in sewer promoted the microorganism proliferation in biofilm, increased the biofilm thickness, re-shaped the microbial community and enhanced biological denitrification and sulfur production, which further weakened the effect of nitrate on sulfide control during the long-term operation. An optimized biofilminitiated sewer process model demonstrated that neither the intermittent nitrate addition nor the continuous nitrate addition was a sustainable strategy for the sulfide control. To minimize the negative impact from sulfide rebounds, a(bi)monthly routine maintenance(e.g., hydraulic flushing with nitrate spike) to remove the proliferative microorganism in biofilm is necessary.

关 键 词：Hydrogen sulfide control Nitrate addition Sewer modelling Sewer management 

分 类 号：X701[环境科学与工程—环境工程] TU992.23[建筑科学—市政工程]