African Journal of
Biotechnology

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12193

Full Length Research Paper

Treatment performance of small-scale vermifilter for domestic wastewater and its relationship to earthworm growth, reproduction and enzymatic activity

Meiyan Xing, Xiaowei Li* and Jian Yang  
State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
Email: [email protected]

  •  Accepted: 30 September 2010
  •  Published: 01 November 2010

Abstract

 

A vermifilter system packed with quartz sands and ceramsite was studied for domestic wastewater treatment. Results showed that good performance of vermifilter was achieved and removal rates were COD (47.3 – 64.7%), BOD(54.78 – 66.36%), SS (57.18 – 77.90%), TN (7.63 – 14.90%), and NH4-N (21.01 – 62.31%), respectively. An increase in hydraulic loading led to a decrease in treatment efficiency and adult earthworm abundance. In addition, activities of protease, alkaline phosphatase (ALP), and cellulase in earthworm body dropped, but superoxide dismutase (SOD) and catalase (CAT) increased with the hydraulic loading. Correlation analysis implied that larger earthworm (>0.3 g) abundance might play more positive role on wastewater treatment in vermifilter, compared to smaller worm. Earthworm enzymatic activities had significant correlation with treatment efficiency of COD and BOD5 by vermifilter. Thus an important relationship exists for earthworm population dynamics and enzymatic activities with COD and BODremoval rates of domestic wastewater by vermifilter.

 

Key words: Vermifilter, wastewater, earthworm, population dynamics, enzymatic activity, treatment efficiency.

Abbreviation

Abbreviations: CV, Ceramsite vermifilter; QV, quartz-sand vermifilter; COD, chemical oxygen demand; BOD5, biochemical oxygen demand; SS, suspended solid; TN, total nitrogen; CAT, catalase; SOD, superoxide dismutase; ALP, alkaline phosphatase.