農業廢棄物資源化及收集模式之研究

Abstract

農業生產過程常伴隨產生大量農業廢棄物，必需進行後續處理作業，若未經妥善處理，容易造成環境危害。農業廢棄物因富含許多有機物及營養源，係屬重要之再利用資源，如何有效進行回收再利用，為當前重要之環境議題。本研究首先探討我國農業廢棄物產出、再利用之相關管理體系及未來發展；另探討我國稻稈集運模式及成本分析，最後亦探討風災垃圾及大量農業廢棄物之產出及清理方法。 我國農業廢棄物可分為公告列管及非告列管兩大項。目前公告列管農業廢棄物產量前五項分別為廢酒糟/酒粕/酒精醪、禽畜糞、製糖濾泥、食品加工污泥及蔗渣，佔總量67%；如以再利用處理技術之處理量排序，依序為飼料原料(43%) > 堆肥(32%) > 再利用原料(15%)，做為燃料原料者，未達 1%。在台灣，未公告列管之農業廢棄物，以稻殼及稻稈為最大宗，而稻稈的處理方式以露天焚燒為主，所產生之粒狀污染物，容易造成嚴重之空氣污染問題。為妥善處理農業廢棄物，讓資源有效再利用暨降低空氣污染，本研究以離地處理為目的，調查稻稈集運作業情形，同時分析集運作業成本，建立臺灣稻稈集運模式。建議未來再利用方向應以再生處理與能源結合或應用於污染物處理，其中富含纖維素蔗渣、稻殼及稻稈，可經由再生技術發展纖維酒精，其亦可製作成纖維、生物碳及活性碳，可用於廢水處理。富含營養鹽之農業廢棄物如豬糞尿等，則可供藻類生產生質柴油及燃料電池產電之用。此外，本研究亦探討風災所產生之垃圾及大量農業廢棄物之產出及清理方法，經分析結果，垃圾及廢樹枝部份，主要以焚化處理為主，污泥以建築材料及填地方式處理；禽畜類屍體採焚化為主、化製為輔，豬牛等大型動物屍體，則以掩埋配合滲出水三級處理為主。同時探討災區作業人員於清理風災廢棄物時，其防疫之相關規定。本研究結果可以提供發展中國家，未來清除處理風災垃圾及大量農業廢棄物之重要參考。

In Taiwan, agricultural process usually accompanies with a large amount of agricultural waste, which requires appropriate treatment. The untreated agricultural waste will cause serious environmental problems. Agricultural wastes are organic- and nutrient-rich materials, which are important bio-resources. Thus, collection and recycling of agricultural waste is an important environmental issue in Taiwan. This study investigated the recent generation of agricultural wastes and their reuse in Taiwan. The agricultural wastes can be divided into regulated and unregulated items. The top five regulated agricultural waste items were waste distillers’ grains/alcohol mash, livestock and poultry feces, sugarcane filter cake, food processing sludge, and bagasse, accounted for 67% of the total amount of regulated agricultural waste. According to the treatment capacity of reuse technologies, the order for reuse types is as follows: feed raw material (43%), compost (32%), reused raw material (15%), as a fuel feedstock only was less than 1%. Among the unregulated agricultural wastes, rice husk and rice straw was the largest. Straw was regarded as an agricultural waste in Taiwan and usually burnt in the field, which cause serious air pollution. In this study, the field survey for rice straw collection and transportation and their cost analysis were conducted to build the model of collection and transportation for rice straw in Taiwan. The future studies should focus on the development of regeneration, renewable energy, and pollution treatment. The cellulose-rich bagasse, rice husk and rice straw can be converted to fiber alcohol, fiber cellulose, biochar and activated carbon. Nutrient-rich agricultural waste such as swine manure and algae can be used as the nutrients to produce algal diesel and microbial fuel cells. In Taiwan, typhoons usually result in a large amount of waste that needs to be removed in a short time. Waste, tree branches and bird carcasses were primarily incinerated, while silt and building materials were buried, and pig and cattle carcasses were placed in a landfill with the tertiary treatment of wastewater. This study also reports on the relevant regulations for prevention of epidemics among personnel working in disaster areas. The results can provide important references for the disposal of typhoon waste in developing countries.