Kinetics of composting rice straw with glue waste at different carbon: Nitrogen ratios in a semiarid environment

Abstract

Abstract Glue waste was mixed with chopped rice straw at carbon:nitrogen (C:N) ratios of 1.5, 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 k 2 of fast‐decaying component. Composting rate constant k 1, A 0/C 0, and (C 0 — C)/C 0 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.