Summary: | 碩士 === 國立高雄第一科技大學 === 環境與安全衛生工程系 === 89 === ABSTRACT
Taiwan produces 3 million tons of vegetable sand 2 million tons of fruits. To bring fruits and vegetables to the consumers, seven hundred thousand tons of wastes are generated at the retails and wholesales markets. In the past, most of the wastes generated at the markets were sent to landfills for final disposal. Since the capacity of landfills sites are limited and the development of many new sites is delayed, the markets have begun to sent the wastes to incineration plants. The incineration is quite uneconomical because the wastes from vegetable and fruit markets have a high moisture content, low density, and low heating value. An alternative way of disposal such as composting or biodegradation using microorganisms is urgently needed.
In the past five years, many medium-to-large scale facilities composting agriculture and animal wastes were established through the government’s assistance. Many of those facilities still have significant empty space.. It is therefore desirable to use those empty space for composting vegetable and fruit wastes.
The purpose of this study is to investigate the feasibility of integrating the vegetable and fruit wastes into existing agricultural and animal husbandry waste composting systems. The wastes generated at the wholesales markets is used as the target for the number of the wholesales markets is limited and the waste generated per market is significant more.
There are 61 wholesale markets distributed in many cities in Taiwan. They produces sixteen hundred thousand tons of wastes. The percentage of these organic wastes is 71.5%-89.5% . There are about thirteen hundred thousand tons of wastes being available for composting. According to the result of the statistic analysis, the regression relationship among wastes(Y), vegetables(X1), and fruits(X2) is Y=0.017 X1+0.11 X2+47.8,R2.=0.898。
At present, there are 42 composting factories counselled by the Councul of Agriculture . The study not only investigates the running situation of these composting factories, but also estimates the possiblity of disposal wastes. Depending on the result, the percentage of the return on the investment is 3.4-26.3% without considering the government''s help. On the other hand, the percentage of return on the investment is 36-98% with the help from the government. If those 12 composting factories can disposal these wastes, they can process about thwelve hundred thousand tons of wastes. For example, in Tainan county they can do wastes from the wholesale markets.
There are two ways of using feedlot wastes composting factories to disposal the vegetables and fruits wastes. One way is to cope with the original material by covering these vegetables and fruits wastes in the product line. Another way is to do these wastes individually by using available landfill sites. By using the first way, the regression relationship between the dealing cost(Y) and the total amount of disposal these wastes(X) is Y=-14.57X+1049.
The cost of composting in north and central Taiwan is 48-65% of the cost of landfilling, and the cost of composting in south Taiwan is 30-35%. In addition, the cost of composting is only 30-35% of the cost of incineration. Therefore, the way of composting wastes is better than landfill or incineration.
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