Abstract The integrated production of biodiesel and biogas has been explored by using N. gaditana, I. galbana and A. platensis as substrate. Three fatty acid ethyl ester (FAEE) production approaches were assessed, namely an indirect process with previously extracted lipids (IPPEL), an indirect process with extracted lipids as free fatty acids (IPELFFA) and a direct process (DP) without a previous lipid extraction stage. Besides de FAEE production, these approaches are considered as pre-treatments of the microbial biomasses evaluated in this study with the objective of increasing the methane yield during the anaerobic digestion. Biogas yields of the residues generated under the three FAEE production methodologies were compared to the biogas yield of the raw feedstock. In all cases, the biodiesel and biogas yields were higher after the FAEE production process from the previously extracted lipids as free fatty acids (IPELFFA). Therefore, this constitutes an interesting and promising route in the joint production of biodiesel and biogas.

中文翻译：

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生物柴油生产中使用的脂质提取方法对小球藻、等鞭金藻和钝顶藻中生物柴油和沼气的综合回收的影响

摘要 以N. gaditana、I. galbana和A. platensis为底物探索了生物柴油和沼气的综合生产。评估了三种脂肪酸乙酯 (FAEE) 生产方法，即使用先前提取的脂质 (IPPEL) 的间接工艺、将提取的脂质作为游离脂肪酸 (IPELFFA) 的间接工艺和没有先前脂质提取的直接工艺 (DP)阶段。除了 de FAEE 生产，这些方法被认为是本研究中评估的微生物生物质的预处理，目的是增加厌氧消化过程中的甲烷产量。将在三种 FAEE 生产方法下产生的残留物的沼气产量与原始原料的沼气产量进行比较。在所有情况下，在 FAEE 生产过程之后，生物柴油和沼气产量更高，从先前提取的脂质作为游离脂肪酸 (IPELFFA)。因此，这构成了联合生产生物柴油和沼气的有趣且有前景的路线。