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Updated: Jul 18, 2026
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Estimating Sediment Denitrification Rates Using Cores and N2O Microsensors
Published on: December 6, 2018
[Study on denitrification characteristics of dynamic membrane based on nitrate liquid-membrane microelectrodes]
Xiao-hong Zhou1, Han-chang Shi, Qiang Cai
1State Key Joint Laboratory of Environmental Simulation and Pollution Control, Department of Environmental Science and Engineering, Tsinghua University, Beijing 100084, China.
Huan Jing Ke Xue= Huanjing Kexue
|November 23, 2006
Summary
This study used nitrate and ORP microelectrodes to investigate denitrification in dynamic membranes. Higher chemical oxygen demand (COD) loading increased the denitrification zone, optimizing nitrate removal rates.
Area of Science:
- Environmental Science
- Environmental Engineering
- Microbiology
Context:
- Dynamic membranes are crucial in wastewater treatment for efficient pollutant removal.
- Understanding microbial processes within biofilms is key to optimizing treatment efficacy.
- Denitrification is a critical step in removing nitrogen pollution from wastewater.
Purpose:
- To investigate the denitrification characteristics of dynamic membranes under varying chemical oxygen demand (COD) loadings.
- To determine the optimal COD loading for maximum denitrification rates.
- To analyze the spatial distribution and factors influencing denitrification within the dynamic membrane.
Summary:
- Nitrate and ORP microelectrodes revealed denitrification occurring 0.6-1 mm below the biofilm/bulk interface, with optimal ORP values between -88.6 and -128.4 mV.
- Maximum denitrification rate (0.6347 x 10^-6 mol/(L x s)) was achieved at a COD loading of 0.45 kg/(m³·d).
- Increased COD loading expanded the denitrification zone and led to the emergence of distinct layers with varying rates, suggesting complex interactions.
Impact:
- Provides insights into the microbial ecology and process dynamics of denitrification in dynamic membrane systems.
- Highlights the influence of organic matter concentration, oxygen availability, and bacterial competition on denitrification efficiency.
- Offers data for optimizing dynamic membrane bioreactors for enhanced nitrogen removal in wastewater treatment.
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