The objectives of this project are to evaluate the current status for the treatment and reuse of five types of organic waste in Taiwan, namely sludge from food waste, pruned/trimmed branches and leaves from fruit trees, fruits and/or vegetable waste, floral waste, and waste mushroom grow bags; collect and analyze potential domestic and foreign organic waste treatment and reuse technologies; and use the gathered information to propose integrated reuse demonstration system for the aforementioned five types of waste. Through gathering and analysis of relevant data, and on-site visits to various treatment plants to collect information on organic waste generation as well as their treatment and reuse status, the investigation on the treatment and reuse of the 5 types of organic waste has been completed. On the study of foreign treatment and reuse technologies for organic waste, relevant information from Denmark, Germany, Japan, United Kingdom, India, the Netherlands, United States, and the EU, have been collected and evaluated. The collected information has been complied and presented in the project report, and used as information inputs for the proposal and recommendations for the planning on domestic treatment and reuse for organic waste. On the recommendations for the demonstration system for reuse of organic waste, of the five types of organic waste under studied, the food waste sludge and vegetable/fruits waste have higher moisture content (often greater than 70%) and are better suited for biological treatment. The fruit/vegetable waste is similar to the kitchen waste, and can be incorporated into the existing kitchen waste recycling and reuse system technically. However, the over 50 public kitchen waste composting plants in Taiwan on average have all operated at over 100% capacity, and will be unable to take in any more fruit/vegetable waste. It is therefore recommended that the fruit/vegetable waste be considered for anaerobic digestion treatment in the future, or after consultation and consent of the Council of Agriculture, be co-composted in the existing livestock manure composting plants. Currently, most floral waste in Taiwan is mixed with fruit/vegetable waste during collection, and its separate collection has been difficult except for the few large scale flower distribution centers. The waste mushroom grow bags is a local waste with high humus content and about 50% moisture content. After removing the plastic packaging from the bags, the mushroom grow material can be used as a filling material for the compost process, or it can be used as a fuel after reducing its moisture content. The pruned/trimmed tree branches and leaves have a wide range of domestic distribution. Due to their low water content and high heat value, this type of waste should be subjected to thermal treatment (e.g., gasification or thermal cracking, refuse-derived fuel (RDF), etc.) to recover their energy content. Therefore, the focus should be on providing technical assistance for moisture removal of such waste at the site of generation, and strengthen efforts on waste composting. If the moisture content of such waste can be reduced to less than 10%, it can be used as the input material for gasification/thermal cracking process. The National Consultation and Technology Demonstration Meetings for Treatment and Reuse of Organic Waste have been held on November 17 and 19 respectively. The meetings were attended by 4 scholars/technical experts and representatives from the Council of Agriculture, Ministry of Economic Affairs, local environmental protection agencies, waste treatment sector, and farmers associations, and discussions were conducted on the strategic, regulatory, technical, market and implementation aspects of this issue among the participants. Overall, it is recommended that the long-term goals for promoting treatment and reuse of organic waste should be on comprehensive recycling, diversified utilization, respect for local conditions, and making use of cooperation mechanism, in order to improve their recycling efficiency and achieve sustainable recycling economy.

Organic waste, food waste sludge, reuse