畜牧污泥厭氧消化對溫室氣體減量之評估

Abstract

畜牧排泄物所排放的溫室氣體 (GHGs) 為目前全球能源及環境的重要議題。農業及畜牧廢棄物為台灣最豐富的有機廢棄物，於 1995-2007年間，處理畜牧排泄物所產出的甲烷估計量為 36-56 Gg/year；根據豬隻糞便的特性，甲烷產出潛能之最大值可達 400 Gg/year。國內畜牧廢水主要採用農委會畜產試驗所所研發的三段式廢水處理系統。廢水處理後會產生大量污泥，且污泥含高濃度之有機物，亦即具甲烷產出潛能；若污泥未經適當處理回收再利用，將造成環境二次污染。為降低溫室氣體排放以減少對自然環境之衝擊，建立有效的污泥處理及資源回收再利用技術，是現今世界各國努力的方向。畜牧污泥經厭氧消化反應產出生物氣體 (biogas) 為減少溫室氣體排放的有效方法之一。本計畫目的為評估厭氧生物技術處理畜牧污泥，以降低溫室氣體的排放。本計畫的重要工作項目為畜牧污泥產量、污泥種類、污泥性質之調查分析，推估污泥厭氧消化降解揮發性固體物及產生甲烷，評估溫室氣體減量之潛勢。研究成果可提供政府相關單位針對畜牧廢棄物增進溫室氣體減量管理法規及政策之參考。

The emissions of greenhouse gases (GHGs) from livestock wastes?(including wastewaters)?are becoming significant energy and environmental issues in the world. Agricultural and livestock wastes in Taiwan have been recognized as the most abundant organic wastes. The potential of methane generation from livestock manure management in Taiwan during the period of 1995-2007 has been estimated to range from 36 to 56 Gg/year. Based on the characteristics of swine manure, the maximum potential of methane generation could reach to around 400 Gg/year.?Currently, the piggery wastes from hog farmers are mostly treated by the three-step wastewater treatment.?It generates?large amount of sludge at wastewater treatment plants. Handling and disposal of sludge need considerable attention because of its high organic content. To prevent emissions of greenhouse gases (GHGs) to the natural environment it is necessary to develop an optimal recycling biotechnology from production to utilization. Biogas production from anaerobic digestion of livestock sludge and slurries is an effective way of reducing greenhouse gas emissions. The purpose of the proposed project is to evaluate the potential of using anerobic biotechnology for?converting?livestock?sludge into biogas and reducing emissions of GHGs.?This?project is forcused ?to investigate the production and characterization of sludge generated in the three-step wastewater treatment. Based on the results of investigation, we can assess the potential of GHGs emissions reduction. The antipated results will be valuable references for governmental regulations and policies for promoting?GHGs emissions?from livestock wastes management.