Kaparaju P, Luostarinen S, Kalmari E, Kalmari J, Rintala J
Department of Biological and Environmental Science, University of Jyväskylä, Finland.
Water Sci Technol. 2002;45(10):275-80.
The possible co-digestion of energy crops and industrial confectionery by-products with cow manure was evaluated firstly, through long-term batch experiments and secondly, in a farm-scale digester. In batch assays, digestion with mesophilically digested cow manure as inoculum resulted in specific methane yields (m3 kg(-1) VS added waste) of 0.35 for grass hay (particle size <1.0 cm); 0.26 for oats (0.5 cm) and 0.21 for clover (2.0 cm) harvested at vegetative stage and 0.14 (2.0 cm) for clover harvested at flowering stage. Specific methane yields (m3 kg(-1) VS added waste) for confectionery by-products were 0.37 for chocolate, 0.39 for black candy and 0.32 for confectionery raw material. Out the three particle sizes (2.0, 1.0 and 0.5 cm) tested, particle size of 1.0 cm was found ideal for digestion of grass hay and clover while, particle size reduction did not influence methane production from oats. Stage of the crop influenced the methane yields, with clover harvested at vegetative stage yielding 33% higher methane than when harvested at flowering stage. An approximate 60% enhancement in methane yield was noticed with the co-digestion of industrial confectionery wastes with cow manure in a full-scale farm digester.
首先通过长期批次试验，其次在农场规模的消化器中，对能源作物和工业糖果副产品与牛粪进行共消化的可能性进行了评估。在批次试验中，以中温消化的牛粪作为接种物进行消化，对于在营养阶段收获的禾本科干草（粒径<1.0厘米），特定甲烷产量（立方米/千克添加废物的挥发性固体）为0.35；对于燕麦（0.5厘米）为0.26，对于三叶草（2.0厘米）为0.21，对于在开花阶段收获的三叶草（2.0厘米）为0.14。糖果副产品的特定甲烷产量（立方米/千克添加废物的挥发性固体），巧克力为0.37，黑糖果为0.39，糖果原料为0.32。在所测试的三种粒径（2.0、1.0和0.5厘米）中，发现1.0厘米的粒径对于禾本科干草和三叶草的消化是理想的，而粒径减小对燕麦的甲烷产生没有影响。作物的阶段影响甲烷产量，在营养阶段收获的三叶草产生的甲烷比在开花阶段收获时高33%。在全规模农场消化器中，工业糖果废物与牛粪共消化时，甲烷产量提高了约60%。
