Studies on Variations in Physico-chemical, Biochemical and Biological Characteristics at Different Maturity Stages of Segregated and Unsegregated Urban Solid Waste of Drum Compost

Abstract

Improper disposal of solid waste is one of the main causes of environmental pollution. Converting solid waste into compost and using it as an organic fertilizer in agriculture are an effective waste management method. Quality of such fertilizer may affect both human and environmental health. Therefore, in this study, compost from segregated and unsegregated urban solid waste compost was analyzed for its physical-chemical, biochemical, biological characteristics and the results were compared with the standards. In this descriptive-analytical study, compost samples were collected throughout a 3-month period at intervals of 20 days (2 methods, S1-Segregated, S2-Unsegregated urban compost) for physio-chemical analysis. In the present study, physical parameters such as moisture content, temperature and bulk density were 23.65%, 31 (°C) and 1.01 (g/cm-3). Chemical parameters such as pH, EC, C/N ratio, organic carbon, Total Nitrogen, Phosphorus, Potassium, Ca, Mg, S, Fe, Mn, Cu, Zn, Ni, Pd and Cr content were 7.75, 1.12 (dS m-1), 17.78, 29.16, 1.64, 0.45, 1.11, 1.47, 0.74, 0.76%, 3529.11, 350.67, 41.11 and 118.07(mg kg-1), respectively. The heavy metal concentration viz., nickel, lead, chromium content were 12.75, 23.87 and 12.53 (mg kg-1), respectively. Heavy metals concentration was detected at all the decomposition stages of composting and were to found to be within the permissible limits of Ohai-EAP standards. From the results, it can be concluded that, segregated urban waste composting could produce acceptable quality of compost, which can be used as fertilizer or soil amendment.