Processing of human faeces by wet vermifiltration for improved on-site sanitation

The use of a vermifilter containing Eisenia fetida to degrade human faeces in a continuous wet system was explored. This paper aimed to understand the formation of vermicompost within the system, the quality of the effluent produced, and the effect of different bedding matrices. Eight filters were constructed, utilising four different bedding materials: four of these systems were seeded with 400 g of worms (vermifilters) while the others served as controls. The systems were flushed with 12 L of water per day and the experiment was split into five phases, each with different feeding regimes. Between 23.7 and 24.7 kg of fresh human faecal matter was added to the vermifilters over the 360 day period. The presence of the worms was found to increase the faecal reduction to 76% on average, compared to 17% in the control systems on average. Statistically significant reductions in phosphate, chemical oxygen demand and thermotolerant coliforms were achieved in the effluent of all vermifilters. The most suitable bedding matrix was a mixture of coir and woodchip. This study shows that there is potential for continuous treatment of human faeces using wet, on-site vermifilters.

[1]  V. Tare,et al.  Vermicomposting of source-separated human faeces by Eisenia fetida: effect of stocking density on feed consumption rate, growth characteristics and vermicompost production. , 2011, Waste management.

[2]  Jibiao Zhang,et al.  Enhancement of rural domestic sewage treatment performance, and assessment of microbial community diversity and structure using tower vermifiltration. , 2011, Bioresource technology.

[3]  P. F. Greenfield,et al.  The treatment of domestic wastewater using small-scale vermicompost filter beds , 2003 .

[4]  Vinod Tare,et al.  Vermicomposting of source-separated human faeces for nutrient recycling. , 2010, Waste management.

[5]  Xiaowei Li,et al.  Treatment performance of small-scale vermifilter for domestic wastewater and its relationship to earthworm growth , reproduction and enzymatic activity , 2012 .

[6]  Xiaowei Li,et al.  Treatment performance of small-scale vermifilter for domestic wastewater and its relationship to earthworm growth, reproduction and enzymatic activity , 2010 .

[7]  Meiyan Xing,et al.  Earthworm-microorganism interactions: a strategy to stabilize domestic wastewater sludge. , 2010, Water research.

[8]  M. Applehof.  Worms eat my garbage. , 1982 .

[9]  B. R. Eastman,et al.  The Effectiveness of Vermiculture in Human Pathogen Reduction for USEPA Biosolids Stabilization , 2001 .

[10]  Fen Yu,et al.  A comparative study of synchronous treatment of sewage and sludge by two vermifiltrations using an epigeic earthworm Eisenia fetida. , 2011, Journal of hazardous materials.

[11]  P. Robin,et al.  Continuous village sewage treatment by vermifiltration and activated sludge process. , 2009, Water science and technology : a journal of the International Association on Water Pollution Research.

[12]  Mansoor Ali,et al.  A Critical Review of Technologies for Pit Latrine Emptying in Developing Countries , 2011 .

[13]  A. Parvaresh,et al.  Vermistabilization of Municipal Wastewater Sludge with Eisenia fetida , 2004 .

[14]  A. E. Greenberg,et al.  Standard methods for the examination of water and wastewater : supplement to the sixteenth edition , 1988 .

[15]  Zhibo Lu,et al.  Effect of earthworms on the performance and microbial communities of excess sludge treatment process in vermifilter. , 2012, Bioresource technology.