WANGFeng,LIYu-ping,JIANGYing-ying,et al.Effect of Calcium Peroxide on Nitrogen Transformation in Black and Odorous Water Body and Its Mechanism[J].China Water & Wastewater,2023,39(13):88-94.
Effect of Calcium Peroxide on Nitrogen Transformation in Black and Odorous Water Body and Its Mechanism
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第39卷
Number:
第13期
Page:
88-94
Column:
Date of publication:
2023-07-01
- Abstract:
- The calcium peroxide (CaO2) in-situ capping method was used to repair the simulated black and odorous river, and the dynamic changes in DO, ORP, nitrogen form and concentration, and the key functional microorganisms in the sediment were investigated under different dosages of CaO2, so as to solve the problem that NH4+-N was difficult to decrease in the black and odorous river channels. When CaO2 dosage was 0.16 kg/m2 (measured by sediment), the DO of water reached up to 7.9 mg/L, the ORP increased from -44 mV to 108 mV, and the removal rates of TN and NH4+-N from the overlying water reached 72% and 94%, respectively. CaO2 led to temporal changes of DO in the mud-water system (aerobic, anoxic and anaerobic). The high-throughput sequencing results showed that Nitrosomonas (relative abundance of 2.51%) and Nitrobacter (relative abundance of 2.69%) converted NH4+-N into NO3--N on day 7 (DO was greater than 2 mg/L) when the dosage of CaO2 was 0.16 kg/m2. On day 13 (DO was 0.5-2 mg/L), Nitrosomonas (relative abundance of 1.76%) converted NH4+-N into NO2--N. On day 20 (DO was less than 0.5 mg/L), denitrifying bacteria such as Thermomonas (relative abundance of 1.69%), Enterobacter (relative abundance of 2.48%) and Denitratisoma (relative abundance of 0.32%) reduced NO3--N and NO2--N to N2. CaO2 effectively improved the DO condition of the mud-water system, leading to the dynamic changes in denitrifying microorganisms, recovery of the self?purification denitrification efficiency of water body, and occurrence of biological nitrogen removal through nitrification and denitrification, so as to achieve the purpose of black and odorous water body remediation.
Last Update:
2023-07-01