Kinetics of Composting Rice Straw with Glue Waste at Different Carbon: Nitrogen Ratios in a Semiarid Environment

Glue waste was mixed with chopped rice straw at carbonmitrogen (C:N) ratios of1.5, 24.8, 30.3, 35.4, 39.9, and 116.3 and allowed to compost for 128 days under aerobic conditions. Moisture was kept constant at 65% (w/w). Organic carbon was determined at 0, 6, 14, 20, 26, 32, 44, 56, 68, 80, 92, 104,116, and 128 days. Two parallel first-order kinetics were found for describing the process of composting. Decomposition percentage increased linearly with the composting rate constant k2 of fast-decaying component. Composting rate constant k₁, A₀/C₀, and (C₀ — C)/C₀ were C:N ratio dependent. Optimal C:N ratio for obtaining early and efficient composting was 30.3. Half-life of fast decaying component was within one week for different materials. Glue waste compost had a nitrogen loss of 44.7%. This study evolved a cheap and practical biotechnology to convert agricultural and industrial waste into a beneficial compost by increasing decomposition rate, reducing pungent odor of glue waste, and narrowing C:N ratio to acceptable limits.