A novel sanitation model based on EcoSan philosophy

Zero Discharge Toilet System (ZDTS) which incorporates EcoSan philosophy and the advantages of water flushed system has been described in this paper. The system uses a solidliquid separator and a thin flat filter which enables recycling for flushing the toilet pan and separate collection of urine and fecal slurry. Inorganic liquid or solid fertilizer is obtained by concentrating the liquid residue. The solid residues containing around 2 % solids are first processed using activated composting and finally polished to obtain quality organic manure using vermicomposting. The quality of product is much superior as indicated by higher water holding capacity and much lower total carbon, volatile solids, coliforms and C/N ratio. The zero discharge toilets are well accepted among users. The residues generated per person are about 1/5 th as compared to conventional toilet system. ZDTS has lower capital cost and higher NPV as compared to conventional wastewater treatment system.