Department of Environmental Science and Technology, University of Maryland, 1445 Animal Sci./Ag. Eng. Bldg., College Park, MD 20742-2315, USA.
Bioresour Technol. 2010 Jun;101(12):4362-70. doi: 10.1016/j.biortech.2010.01.100. Epub 2010 Feb 11.
A co-digestion investigation was conducted using small-scale digesters in Costa Rica to optimize their ability to treat animal wastewater and produce renewable energy. Increases in methane production were quantified when swine manure was co-digested with used cooking grease in plug-flow digesters that operated at ambient temperate without mixing. The co-digestion experiments were conducted on 12 field-scale digesters (250 L each) using three replications of four treatment groups: the control (T0), which contained only swine manure and no waste oil, and T2.5, T5, and T10, which contained 2.5%, 5%, and 10% used cooking grease (by volume) combined with swine manure. The T2.5 treatment had the greatest methane (CH(4)) production (45 L/day), a 124% increase from the control, with a total biogas production of 67.3 L/day and 66.9% CH(4) in the produced biogas. Increasing the grease concentration beyond T2.5 produced biogas with a lower percentage of CH(4), and thus, did not result in any additional benefits. A batch study showed that methane production could be sustained for three months in digesters that co-digested swine manure and used cooking grease without daily inputs. The investigation proved that adding small amounts of grease to the influent is a simple way to double energy production without affecting other digester benefits.
在哥斯达黎加，使用小型消化器进行了共消化研究，以优化其处理动物废水和生产可再生能源的能力。当在没有混合的常温下运行的推流式消化器中，猪粪与使用过的食用油共消化时，甲烷产量增加了。在使用三个重复四个处理组的 12 个现场规模消化器（每个 250 升）上进行了共消化实验：对照（T0），仅包含猪粪且没有废油，以及 T2.5、T5 和 T10，其中包含 2.5%、5%和 10%（按体积计）的使用过的食用油与猪粪混合。T2.5 处理的甲烷（CH(4)）产量最高（45 L/天），比对照增加了 124%，总沼气产量为 67.3 L/天，产生的沼气中 CH(4) 为 66.9%。将油脂浓度增加到 T2.5 以上会产生沼气，其中 CH(4)的比例较低，因此没有带来任何额外的好处。一项批处理研究表明，在无需每日投入的情况下，猪粪和使用过的食用油共消化的消化器中，甲烷生产可持续三个月。该研究证明，向进料中添加少量油脂是一种在不影响其他消化器利益的情况下将能源产量提高一倍的简单方法。
