Mitigation of greenhouse gases emission through food waste composting & replacement of chemical fertiliser

Abstract

A pilot scale composting plant has been established on-campus in Universiti Teknologi Malaysia (UTM) to achieve the goal as a sustainable campus. Portion of organic wastes were diverted from landfilling by converting it into compost (organic fertiliser) for reducing greenhouse gases (GHG) emission at the landfill and the dependency on inorganic fertiliser. Composting has been reported as a sustainable approach to reduce the footprint of GHG as compared to the waste disposal through landfilling. However, the amount of GHG emitted during composting can vary due to localised condition. The aim of this study was to assess the potential of composting in mitigating GHG emission compared to the current waste management employed in UTM (Landfilling). A business as usual (BAU) scenario represents the current organic waste management practice in UTM was established. Composting was proposed as an alternative scenario. The amount of GHG emitted or reduced from different sources including for transportation, waste processing, waste treatment as well as downstream activities such as carbon sequestration and inorganic fertiliser substitution was estimated based on lifecycle inventory analysis. The result indicated that composting scenario offer a GHG reduction of 66.72 % as compared to the BAU scenario. The fugitive emission from biodegradation of organic waste contributed significantly to the GHG emission for both scenarios whereas the GHG emission from the fossil fuel combustion was considered as not significant. The overall result suggested the potential of composting as a viable technology for sustainable organic waste management in UTM.