New M.E.Thesis Submitted from Civil (Env.)

Bio-Conversion of Commingled Waste using Advanced Composting Technique by Kashish Jain

Abstract

Indian metropolises have been confronting a severe MSW problem. Like many cities in developing world, the municipal authorities responsible for gathering, carriage and disposal in India rarely have adequate policies, techniques, methods for utilization of financial resources or the much needed suitable infra for structured waste management. So there‘ve been consistent exertions to tackle this menace economically and efficiently. Although, incineration and landfilling provides an easy escape but the most cost-effective method which always comes to the rescue of a layman and can easily be practiced independently or publicly is of Composting. Though natural, energy efficient and an easy technique of MSW handling and conversion with not many inputs required, this method has always been time consuming and posing hindrance at compost manufacture locates with space constrictions. This study thus deals with the development of a new composting technique called Hot Composting with Extended Microbial Solution (HCEMS) and comparing the same with the vermi-composting (VC) practice to check for the enhancement in parameters such as compost maturity period, nutrient concentrations and space requirements. The new system used composting at raised temperatures in combination with addition of EM solution so as to intensify the decomposition by using both mesophillic and thermophillic microbes. While the mesophillic bacteria such as bacillus, streptococcus worked during initial low temperature condition, the thermophillic ones such as fungi, actinomycete worked at high thus doubling the decay rate. In VC, the worm eisenia fetida was employed. Regular monitoring of pH, moisture content and temperature was done. Other parameters like the TOC, total N, phosphates, potassium and C/N were also checked periodically to govern the compost maturity. The final compost prepared in case of HCEMS showed a good improvement in all nutrient characteristics when compared to VC with an increase of 30.51% in total N, 5.33% in P and 64.45% in K values. Even the final product attained maturity in just 30 days in case of HCEMS with respect to VC which attained the same in 80 days. Also, the processing was possible at the rate of 24.8 tonnes of waste per m2 of land; however it was only 3.55 tonnes per m2 in VC. Further, a proximate analysis was done to conclude the amount of decay which was also greater in the new technique. The proximate analysis also showed the decomposition of lignin which otherwise was unable to achieve in conventional methods. In general, the new technique developed showed higher productivity and should find its way into the regular composting practices replacing the conventional techniques.