Rapid Composting Using a Novel Agricultural Waste Shredder

Abstract

Agricultural waste causes social and environmental pollution, affecting global health. Converting agricultural waste to organic manure reduces the problems of pollution. Existing machine used in conversion has low efficiency in terms of throughput capacity and size reduction, leading to slow composting. This study focuses on the evaluation of a specially developed waste shredder for fast composting (maize straw). The machine was designed to handle substantial volumes of agricultural waste, operated at different speeds (i.e. 300, 600, 900, 1200 and 1500 rpm) and time (i.e. 0.5, 10, 1.5, 2.0 and 2.5 hr). The components of the machine included shredding drum equipped with three sets of blades, a feeding tray, sieve, engine seat and an outlet. Performance evaluation carried on the machine includes shredding efficiency and throughput capacity. A standardized Response surface methodology (RSM) was employed to maximize efficiency varying the operational speeds and shredding time. Results showed achieved maximum shredding efficiency of 91% and maximum throughput capacity of 585 kg/hr when the machine was operated at 1,500 rpm for 1.5 hr. In addition, the machine is portable, low energy and easy to operate for any agricultural waste.