A critical factor in environmental degradation is the coupled problem of world population growth and waste management, including wastewater management. Making biodiesel from the FOG (fat, oil and grease) in the wastewater system is an attractive path for sustainable biofuel production, waste management and public health. High sulfur content is the biggest challenge in biodiesel produced with the brown grease extracted from FOG.

The purpose of this paper is to present a new method to design the sulfur reduction process based on a pseudo-component approach that greatly reduces the effort required to characterize the complex mixture of methyl esters and sulfur containing contaminants. To demonstrate this method, biodiesel was produced from decanted brown grease using several combinations of acid and base catalysts in a two-step esterification/ transesterification process. Vacuum batch distillation was applied to the crude biodiesel product to generate volatility and sulfur distribution data. An easily applied vapor/liquid equilibrium model was then developed using 7 pseudo-components, each with an assigned sulfur content. A principal result is that the pseudo-component model very accurately simulated the batch distillation data. These pseudo-components were then used in the ASPEN software to design a continuous distillation system for a FOG to biodiesel system being installed at a wastewater treatment plant. The second principal result is the ASPEN based design predicts a biodiesel product containing sulfur lower than 10 ppm, satisfying sulfur requirements worldwide. In conclusion, the pseudo-component design method is a versatile and easily applied approach to design sulfur reduction processes.

环境退化的一个关键因素是世界人口增长和废物管理（包括废水管理）的耦合问题。从废水系统中的 FOG（脂肪、油和油脂）制造生物柴油是可持续生物燃料生产、废物管理和公共卫生的一条有吸引力的途径。高硫含量是使用从 FOG 中提取的棕色油脂生产的生物柴油的最大挑战。

本文的目的是提出一种基于伪组分方法设计硫还原过程的新方法，该方法大大减少了表征甲酯和含硫污染物的复杂混合物所需的工作。为了证明这种方法，在两步酯化/酯交换过程中，使用几种酸和碱催化剂的组合，从倾析的棕色油脂中生产生物柴油。真空分批蒸馏应用于粗生物柴油产品以生成挥发性和硫分布数据。然后使用 7 种伪组分开发了一个易于应用的气/液平衡模型，每个伪组分都有指定的硫含量。主要结果是伪组分模型非常准确地模拟了分批蒸馏数据。然后在 ASPEN 软件中使用这些伪组件来设计一个连续蒸馏系统，用于安装在废水处理厂的 FOG 到生物柴油系统。第二个主要结果是基于 ASPEN 的设计预测含硫量低于 10 ppm 的生物柴油产品，满足全球对硫的要求。总之，伪组分设计方法是一种通用且易于应用的硫还原工艺设计方法。