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Updated: Apr 14, 2026

Estimating Sediment Denitrification Rates Using Cores and N2O Microsensors
Published on: December 6, 2018
The heterotrophic-combined-with-autotrophic denitrification process: performance and interaction mechanisms
Guihua Xu1, Cuijie Feng2, Fang Fang2
1Key Laboratory of Reservoir Aquatic Environment, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China; Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
The heterotrophic-autotrophic denitrification (HAD) system simultaneously removes chemical oxygen demand, sulfide, and nitrate. This combined process effectively utilizes surplus nitrite, enhancing overall denitrification rates.
Area of Science:
- Environmental Science
- Microbiology
- Water Treatment
Background:
- Simultaneous removal of contaminants like chemical oxygen demand (COD), sulfide, and nitrate is crucial for wastewater treatment.
- Understanding the interaction between heterotrophic denitrification (HD) and autotrophic denitrification (AD) is key to optimizing combined systems.
Purpose of the Study:
- To investigate the interaction mechanisms between AD and HD processes within a HAD system.
- To evaluate the performance of the HAD system under varying S/Ac(-) molar ratios.
Main Methods:
- Investigated interaction mechanisms between autotrophic denitrification (AD) and heterotrophic denitrification (HD) processes.
- Evaluated performance of the heterotrophic-autotrophic denitrification (HAD) system.
- Analyzed the impact of different S/Ac(-) molar ratios on the system's efficiency.
Main Results:
- The HAD system demonstrated simultaneous removal of COD, sulfide, and nitrate.
- HD process showed a faster reduction of NO(3)(-) to NO(2)(-) compared to AD.
- AD process efficiently utilized surplus NO(2)(-) from HD, mitigating NO(2)(-)-N accumulation and increasing denitrification rates.
- Observed inhibition effects of acetate on AD bacteria and sulfide on HD were compensated by NO(2)(-) promotion.
Conclusions:
- The HAD system is a promising technology for simultaneous contaminant removal.
- AD and HD processes appear to operate in parallel within the HAD system without significant mutual disturbance.
- Optimizing S/Ac(-) molar ratios can enhance the efficiency of HAD systems.
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