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Published on: December 25, 2015
[Aerobic nitrifying granulation fed with source-separated urine in sequencing batch reactor].
Xue Zou1, Fei-yun Sun, Cheng-yong Yang
1School of Civil Engineering & Architecture, Beijing Jiaotong University, Beijing 100044, China. zouxue_001@sina.com
Huan Jing Ke Xue= Huanjing Kexue
|November 10, 2007
Summary
Aerobic nitrifying granules effectively removed ammonia and chemical oxygen demand from source-separated urine. These granules exhibited enhanced settleability and metabolic activity, crucial for efficient wastewater treatment.
Area of Science:
- Environmental Microbiology
- Environmental Engineering
- Biotechnology
Context:
- Wastewater treatment presents challenges in removing nitrogenous compounds and chemical oxygen demand (COD).
- Source-separated urine is a nutrient-rich wastewater stream requiring effective treatment methods.
- Aerobic granular sludge technology offers a promising approach for wastewater purification.
Purpose:
- To investigate the morphological characteristics and performance of aerobic nitrifying granules in treating source-separated urine.
- To compare the efficacy of aerobic nitrifying granules with conventional nitrifying bacteria in sequencing batch reactors (SBRs).
Summary:
- Two lab-scale sequencing batch reactors (SBRs) were used to treat source-separated urine.
- One SBR, inoculated with nitrifying bacteria, showed low nitrification rates and minimal COD reduction.
- The second SBR, inoculated with pre-cultivated aerobic granules, achieved over 90% removal of COD and ammonia, demonstrating stable performance for 70 days.
- The resulting aerobic nitrifying granules displayed excellent settleability and metabolic activity, with nitrifying bacteria and cocci on their surface.
- These granules were smaller in diameter (over 2 mm) but had a greater settling velocity compared to the inoculating aerobic granules.
Impact:
- Demonstrates the successful application of aerobic nitrifying granules for efficient treatment of source-separated urine.
- Highlights the superior performance of aerobic granules over conventional nitrifying bacteria for simultaneous COD and ammonia removal.
- Provides insights into the characteristics of stable aerobic nitrifying granules, including morphology, settleability, and microbial composition.
- Offers a potential solution for nutrient recovery and wastewater management in decentralized systems.
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