Evaluation of vermifiltration process using natural ingredients for effective wastewater treatment Tarun Kumar a, *, Renu Bhargava a , K.S. Hari Prasad a , Vikas Pruthi b a Department of Civil Engineering, Indian Institute of Technology Roorkee, Roorkee 247667, India b Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee 247667, India A R T I C L E I N F O Article history: Received 13 July 2014 Received in revised form 10 November 2014 Accepted 28 November 2014 Available online xxx Keywords: Vermifiltration Eisenia fetida Filter media Onsite wastewater treatment Indicator organisms A B S T R A C T The present investigation focused on the evaluation of vermifiltration process using different natural ingredients as a media. The vermifilter was evaluated using different natural ingredients viz river bed material, wood coal, glass balls, mud balls and employing Eisenia fetida as an earthworm species. The complete study was carried out for 90 days. The average COD removal for different material i.e. river bed material, wood coal, glass balls and mud balls was found as 72.3, 64.6, 61.5 and 59.8% while average BOD removal was observed as 81.2, 74.5, 72.7 and 70.9%, for respective filter media. Similarly, the total suspended solid removal was observed as 75, 64, 59 and 55%, respectively for above mentioned different media. The river bed material revealed maximum reduction of indicator organisms like total coliform (3.6  0.90 log unit), fecal coliform (3.4  0.67 log unit), fecal streptococci and Escherichia coli (2.5  0.51 log unit). At the end of the run vermicompost obtained through vermifiltration process as a byproduct were found to be rich in nitrate (31.2  5.9 mg/L), phosphate (18.1  4.6 mg/L) which could be exploited in sewage farming. ã 2014 Elsevier B.V. All rights reserved. 1. Introduction The wastewater generation and its treatment has become an important health issue in the developing countries due to the inadequate treatment facilities (Singh et al., 2014). The discharge of untreated sewage in surface and sub-surface water courses is the most important source of contamination of water resources. Most of the population living in rural and urban areas of developing countries depends upon onsite systems for the treatment of domestic wastewater. The treatment systems that require rela- tively low costs, energy, and maintenance are preferable for the treatment of rural domestic wastewater (Sharma et al., 2014; Sharma and Kazmi, 2014). The numerous solutions have been adopted for the treatment of domestic wastewater specially in rural areas, including constructed wetlands, soil infiltration trenches, vegetation-based wastewater treatment and vermifiltra- tion (Cuyk et al., 2001; Ham et al., 2007; Kaoru et al., 2010; Sinha et al., 2008). Among these technologies, the vermifiltration has represented its efficacy as other technologies are restricted to large occupying area (Kumar et al., 2014). In addition, the vermifiltration has the potential which separates wastewater solids by allowing wastewater to be gravity-fed over the filtration material. During vermifiltration process, the earthworm acts as bio-filter that reduces the unwanted organic waste from the wastewater (Manyuchi et al., 2013). It is the most promising economical method for treating point and diffused sources of domestic wastewater. In vermifilter, the earthworms stimulate and acceler- ate the microbial activity by increasing the population of soil microorganisms (Sinha et al., 2008). The present study is concerned with evaluating the effect of different filter media as a vermifilter bed on the performance of vermifilter. For this purpose, the vermifiltration experiments were conducted using four different easily available and cost effective natural ingredients as a filter media. Xing et al., (2011) studied the health of earthworms and change in final characteristics of treated sludge from vermifiltration using ceramsite and quartz sand material. In their investigation ceramsite material was found to be relatively better media for the process with better characteristics of sewage sludge and health of earthworms. The earlier studies have also shown the use of converter slag–coal cinder as suitable media for vermifiltration process (Wang et al., 2010). However, their study was limited to the analysis of nutrients removal like ammonia nitrogen, phosphorous and organic contaminants. Despite recent advancement, vermifiltration is still in its infancy and needs a better media that could bridge different issues like * Corresponding author. Tel.: +91 7500219079. E-mail addresses: vrma.tarun@gmail.com, ertarun_verma@yahoo.co.in (T. Kumar). http://dx.doi.org/10.1016/j.ecoleng.2014.11.044 0925-8574/ ã 2014 Elsevier B.V. All rights reserved. Ecological Engineering 75 (2015) 370–377 Contents lists available at ScienceDirect Ecological Engineering journal homepage: www.elsevier.com/locate/ecoleng