Quantification of greenhouse gas generation from waste treatment and disposal by life cycle assessment

Life cycle assessment of the present food waste(Garbage)treatment system and new treatment system including recycling process(biogasification，composting and decomposition of the compost in the applied soil)were performed。Seven kinds of waste treatment processes，which are collection，incineration，biogasification，composting，transportation，landfill and decomposition of the compost in the applied soil were combined and 4types of treating scenarios were set as follows：1.incineration(collection-incineration-transportation-landfill)，2.biogasification and incineration(collection-biogasification-transportation-landfill)，3.biasogification and incineration(collection-biogasification-transportation-landfill)；As the environmental impacts，global warming derived from greenhouse gas generation(CO I D22文件D2，CH文件D24文件D2，N文件D22文件D2O)，air acidification by acidic materials generation(NO文件D2，SO装置D2)，final disposal volume of solid waste，generating quantity of hazardous materials(As，Cd，Cr文件D2，Cu，Pb，Hg，Zn and dioxins)。The environment impacts of the present treatment system，which is the incineration scenario，were generally higher than the other scenarios。In the viewpoints of global warming，the composting scenario was the worst scenario and the biogasification and composting scenario was the best scenario。Incineration，composting，decomposition of the compost in the applied soil showed relatively high impacts in the each processes and biogasification reduced the greenhouse effects.The total environmental impacts of the system including biogasification was also lower than that of other treatment system，when all environmental impacts were evaluated。Therefore biogasification is useful as the intermediate treatment for food waste.

Life cycle assessment of the present food waste (garbage) treatment system and new treatment system including recycling process (biogasification, composting and decomposition of the compost in the applied soil) were performed. Seven kinds of waste treatment processes, which are collection, incineration, biogasification, composting, transportation, landfill and decomposition of the compost in the applied soil were combined and 4 types of treating scenarios were set as follows : 1.incineration (collection-incineration-transportation-landfill), 2.biogasification and incineration (collection-biogasification-transportation-landfill), 3.biogasification and composting (collection-biogasification-composting-transportation-decomposition of the compost in the applied soil), 4.composting (collection-composting-transportation-decomposition of the compost in the applied soil). As the environmental impacts, global warming derived from greenhouse gas generation (COィイD22ィエD2, CHィイD24ィエD2, NィイD22ィエD2O), air acidification by acidic materials generation (NOィイD2xィエD2, SOィイD2xィエD2), final disposal volume of solid waste, generating quantity of hazardous materials (As, Cd, CrィイD16+ィエD1, Cu, Pb, Hg, Zn and dioxins) of these 4 types of scenario were evaluated. The environment impacts of the present treatment system, which is the incineration scenario, were generally higher than the other scenarios. In the viewpoints of global warming, the composting scenario was the worst scenario and the biogasification and composting scenario was the best scenario. Incineration, composting, decomposition of the compost in the applied soil showed relatively high impacts in the each processes and biogasification reduced the greenhouse effects. The total environmental impacts of the system including biogasification was also lower than that of other treatment system, when all environmental impacts were evaluated. Therefore biogasification is useful as the intermediate treatment for food waste.