Effect of enrichment on chemical properties of MSW compost

Abstract

The efficacy of inorganic additives (rock phosphate 5%, FeSO 4 1%, and lime 0.63%) meant to perk up the Municipal Solid Waste composting process and to examine the physico-chemical parameters during composting in mechanical composter. Swiftly rise in temperature from mesophilic to thermophilic stage was accompanied by an increase in NH 4 + -N that gradually decrease near the maturation phase. A similar behavior was recorded for pH, which become slightly alkaline at maturity level. Composting process decrease the concentration of total carbon (TC), NH 4 + -N , C:N ratio, and increase the cation exchange capacity (CEC), humification index (HI), degree of polymerization (DP), humification rate (HR), phosphorous, potassium and total nitrogen (TN). Optimum degree of maturity was also tested by germination index (GI). A significant correlation was found between total carbon (TC), C:N ratio, humic acid (HA), fulvic acid (FA), degree of polymerization (DP), humification index (HI), humification rate (HR), cation exchange capacity (CEC) and nitrate. We also obstinate the nitrogen (N) and carbon (C) mineralization in laboratory incubation, using soil amended at rate of 30, 60 and 90 kg-N ha −1 in N mineralization and found an increase in the mineralization of N. It was briefly concluded that inorganic additives promote the decomposition rate and humification process.