Management considerations and environmental benefit analysis for turning food garbage into agricultural resources

The management of food garbage is of great importance because of its high energy consumption, potential environmental hazards and public health risks. In Taiwan, through the competent authorities at all levels and the citizens' participation in sorting household wastes, many recycling efforts have recently been implemented to further utilize it as available resources such as swine feeds and organic fertilizer by composting. As a result, a total of approximately 570 thousand metric tons was recycled with a recycling ratio of about 21.2% on a basis of food garbage generation in 2006, rising over 22% from a year earlier. These figures showed that compulsory garbage sorting has indeed dramatically increased the recycling of food garbage. The objective of this paper is to present and discuss some management considerations in turning food garbage into agricultural resources due to the compulsory garbage sorting directive in Taiwan. The description first aims at the current status in food garbage generation and its recycling, and at the regulatory polices which have become effective since 2000. It also centers on the environmental and agricultural measures on upgrading food garbage recycling. Based on the preliminary analysis of environmental benefit by the Revised 1996 Intergovernmental Panel on Climate Change (IPCC) Guidelines for National Greenhouse Gas Inventories, it is obvious that composting food garbage is superior to that by traditional treatments (i.e., incineration and sanitary landfill) from the viewpoint of reducing greenhouse gases (i.e., CO(2) and CH(4)) emissions.