Abstract Wastewater discharges from restaurants, kitchens, food processing plants and slaughterhouses contain high proportion of fat, oil, and grease (FOG). Critical overview on the attractive features, current state, and needed advancements are timely essential for FOG-derived biodiesel production. Although FOG conversion into biodiesel does not compete with human food, the high contents of moisture and free fatty acids (FFAs) are the main challenges for FOG efficient utilization. The present review discussed the various methods of high FFAs-lipidic feedstocks pretreatment including acid esterification, steam stripping, nanocatalytic technology, biological conversion, glycerolysis, supercritical esterification, and simultaneous in situ conversion. Comparing to other feedstocks, FOG-derived biodiesel showed better characteristics concerning oxidative stability, flash point, cetane number, and total emissions. In addition, most of the FOG-derived biodiesel fuel met the recommendations of the international standards as well as conventional diesel. Due to its lower price, the economic analysis showed that FOG is a strong competitor to other biodiesel feedstocks. The decrease in feedstocks availability, continuous rise in the crude oil prices, life threatening environmental deterioration, and food-versus-fuel debate support FOG to be a potential biodiesel feedstock in the near future. However, the cost of FOG-biodiesel production is still far away from the acceptable ranges to compete fossil diesel. Lastly, this paper suggested a number of future perspectives in order to enhance the economy and feasibility of FOG-derived biodiesel including developing new methods for efficient conversion of brown grease, integrated approaches for sequential production of biofuels from FOG, and co-esterification of FOG with other lipidic feedstocks.

中文翻译：

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脂肪、油和油脂 (FOG) 用于生物柴油生产的潜力：对近期进展和未来前景的批判性回顾

摘要 餐馆、厨房、食品加工厂和屠宰场排放的废水中含有高比例的脂肪、油和油脂 (FOG)。对 FOG 衍生生物柴油生产的吸引力特征、当前状态和所需进步的关键概述是及时必不可少的。尽管 FOG 转化为生物柴油不与人类食物竞争，但高水分和游离脂肪酸 (FFA) 含量是 FOG 高效利用的主要挑战。本综述讨论了高 FFA-脂质原料预处理的各种方法，包括酸酯化、汽提、纳米催化技术、生物转化、甘油解、超临界酯化和同步原位转化。与其他原料相比，FOG 衍生的生物柴油在氧化稳定性、闪点、十六烷值和总排放方面表现出更好的特性。此外，大部分 FOG 衍生的生物柴油燃料符合国际标准的建议以及常规柴油。由于价格较低，经济分析表明 FOG 是其他生物柴油原料的有力竞争者。原料供应的减少、原油价格的持续上涨、威胁生命的环境恶化以及食品与燃料的争论都支持 FOG 在不久的将来成为一种潜在的生物柴油原料。然而，FOG 生物柴油的生产成本仍远未达到与化石柴油竞争的可接受范围。最后，