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15:19
Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
Published on: October 15, 2015
[Reducing sludge production by predation and its factors analysis in conventional activated sludge process]
1Department of Water Pollution Control Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Huan Jing Ke Xue= Huanjing Kexue
|April 30, 2005
Summary
Oligochaete worms in conventional activated sludge (CAS) systems significantly reduce excess sludge production and improve settling. Nais elinguis worms show greater sludge reduction potential than Aeolosoma hemprichicii.
Area of Science:
- Environmental Microbiology
- Wastewater Treatment Engineering
Context:
- Conventional activated sludge (CAS) systems face challenges with excess sludge production.
- Oligochaete worms, specifically Aeolosoma hemprichicii, Nais elinguis, and Pristina aequiseta, were studied in a pilot-scale CAS reactor over 345 days.
Purpose:
- To investigate the impact of high-density oligochaete populations on sludge reduction and settling characteristics in a CAS reactor.
- To evaluate the influence of different worm species (Nais elinguis vs. Aeolosoma hemprichicii) on sludge reduction and effluent quality.
- To identify factors affecting oligochaete growth in wastewater treatment.
Summary:
- Oligochaete worms were maintained at high densities (over 30 worms/mgVSS) for 172 days, significantly reducing sludge production and enhancing sludge settling.
- Nais elinguis demonstrated a higher capacity for sludge reduction compared to Aeolosoma hemprichicii, though its growth more significantly impacted effluent quality, including phosphate release.
- Worm growth did not impede nitrification, but temperature and hydraulic retention time (HRT) were identified as key factors influencing worm proliferation, while solids retention time (SRT) had no effect.
Impact:
- Provides insights into biological methods for mitigating excess sludge in wastewater treatment.
- Highlights the potential of specific oligochaete species for optimizing sludge management and improving treatment efficiency.
- Offers valuable data for understanding the ecological dynamics within activated sludge systems and their effect on effluent parameters.
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