纖維原料解聚產品應用於生質沼氣技術開發

Abstract

有機廢水可被利用於生產生質沼氣，汙水來源包括：畜殖業廢水、生活廢水及工業廢水等，廢水內有機質組成成份不同將影響沼氣產量，如畜殖業廢水多混合畜畜尿液厭氧醱酵條件之碳氮比(Carbon/Nitrogen ratio)較低(約C/N ratio:25)，工業廢水富有碳源，碳氮比過高，因此廢水有機質的利用與沼氣生產量是可提升。目前已知透過調整進料的成份，利用共醱酵技術以彌補單一進料源用在厭氧醱酵時之缺點，將可有效提升沼氣產量，例如碳氮比不足時，添加粗甘油等工業廢棄物，可有效提升沼氣產量。台灣每年產生大量農業廢棄物，農業廢棄物由大量纖維素組成，富有大量有機質，可做為生質沼氣生產之原料，目前農業廢棄物資源並無有效利用，但直接作為沼氣生產原料醱酵時程長(約20~30天)，導致生產成本高，不利於直接用在沼氣生產。 本計畫將利用核能所研發之解聚前處理技術將農產廢棄物轉為醣類及纖維素溶液做為替代生質能源之原料，可協助厭氧醱酵時程縮短，快速將大量有機物轉化為甲烷，不僅有效利用農業廢棄物萃取後的有機物，增加農產廢物的能源經濟價值。本計畫也將探討解聚前處理料源混合廢水共同醱酵，利用厭氧醱酵系統轉化為沼氣，先以批次實驗結果來量化解聚前處理料源之沼氣潛能，以及與廢水共同醱酵時之混合參數，藉由參數操作並應用於連續式厭氧反應系統，達到共醱酵提升總沼氣產量，未來此技術可應用至纖維廢棄物及廢水於沼氣生產之總體規劃，達到資源有效利用目的。

The waste water (including livestock, industrial and domestic sewage) has been utilized to produce biogas, which the characteristics of waste water will affect the biogas production. For example, the livestock sewage which containing urine has low carbon/nitrogen ratio (C/N ratio), and industrial waste water has high C/N ratio. Biogas production are known can be elevated by using co-digestion with other substrates can balance the condition of substrate’s influent. When the influent has low C/N ratio, the high C/N ratio supplement, such as glycerol can be added to elevate the biogas production. There are magnificent agriculture wastes, which containing rich carbohydrates and cellulose in Taiwan, are considered as substrate of renewable energy, and for now are not be used advisable. Due to properties of raw agriculture wastes need long hydraulic retention time to decompose the cellulose structure, and will increasing the cost of anaerobic digestion directly. In order to utilize agricultural waste for bioenergy production, this study we use de-aggregation pretreatment to hydrolysis biomass to carbohydrates and cellulose, which can shorten the process of anaerobic digestion and accelerating the biogas transformation. Development of de-aggregation pretreatment is not only for the economic value but also transform the organic contains into alternative energy effectively. In addition, we will using anaerobic co-digestion with the de-aggregation pretreatment resource and waste water to produce biogas in this study. Thus, the biogas production potential will be estimated by mixture with different ratio and resource in batch test, and the continuously anaerobic digestion parameters will also be established. The results of this study can provide an operation standard on mixture of cellulose waste and waste water, to achieve the resource recycling.