[Nitrogen removal by enhanced endogenous denitrification with excess activated sludge reduction technology]
Jian-Long Wang1, Yong-Zhen Peng, Yong-Qing Gao
1School of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100022, China. wjl-xt@163.com
Huan Jing Ke Xue= Huanjing Kexue
|April 30, 2008
Summary
This study introduces a hydrolysis/anoxic/oxic (H/A/O) process for efficient nitrogen removal and excess activated sludge reduction in wastewater treatment. The H/A/O system achieved high removal rates for COD, NH4+-N, and TN without external carbon sources.
Area of Science:
- Environmental Engineering
- Biotechnology
- Wastewater Treatment
Context:
- Traditional wastewater treatment faces challenges with nitrogen removal efficiency and excess activated sludge production.
- Endogenous denitrification offers a potential pathway for nitrogen removal but requires optimization.
- Simultaneous reduction of excess activated sludge is crucial for sustainable wastewater management.
Purpose:
- To investigate the efficacy of a novel hydrolysis/anoxic/oxic (H/A/O) process for simultaneous nitrogen removal and excess activated sludge reduction.
- To evaluate the performance of the H/A/O process without external carbon sources or alkalinity addition.
- To determine the optimal operating conditions for nitrogen removal and sludge reduction.
Summary:
- A pilot-scale H/A/O system was implemented for continuous domestic wastewater treatment.
- The process achieved high removal efficiencies for Chemical Oxygen Demand (COD) (>90%), Ammonium Nitrogen (NH4+-N) (>95%), and Total Nitrogen (TN) (>75%).
- A significant excess activated sludge reduction rate of 56.2% was observed, with hydrolysis enhancing biodegradability and nutrient removal.
Impact:
- The H/A/O process demonstrates a feasible and effective method for simultaneous wastewater treatment and sludge reduction.
- Hydrolysis as a pre-treatment step improves wastewater biodegradability and nutrient removal efficiency.
- The findings contribute to more stable and sustainable wastewater treatment system operations.
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