Iterative lumping approach for representing lipid feedstocks in fatty acid distillation simulation and optimization

Abstract

The complexity of lipid feedstocks and the lack of data on physical properties hinder the simulation of oleochemical processing units. In this work, an iterative lumping approach is proposed to define an adequate number of key compounds such that diversification between lipid feedstocks becomes possible, while keeping the determination of physical properties as required for process modeling manageable. As a case study, the iterative lumping approach is used for simulation and optimization of a fatty acid distillation plant. For predicting vapor-liquid equilibria of fatty acids, the best results were acquired using the property method universal quasichemical-Hayden-O'Conell. Using the iterative lumping approach, 11 key compounds were selected to represent the feedstock. The process model properly predicts the product composition, yield, purity and heat duty. The most important process parameters are found to be side-reflux-ratio, reboiler-outlet-temperature, and heat-duty of the pitch-distiller. For optimization, an increase of the side-reflux-ratio and reboiler-outlet-temperature is recommended.

Simulation of an Industrial-Scale Reactive Liquid–Liquid Extraction Tower Using Polar PC-SAFT Toward Understanding and Improving the Hydrolysis of Triglycerides

“…The feedstocks used in the hydrolysis are complex mixtures of glycerides, free fatty acids (FFA), and minor components. A simplified composition is used in which the components are lumped and represented by a set of key components . A detailed composition of the feedstocks is given in Table S5 of the Supporting Information.…”

“…This motivates developing a process model of triglyceride hydrolysis to investigate the optimal processing parameters for different renewable feedstock types. A process model of triglyceride hydrolysis could be used to investigate if high-quality fatty acids can be produced from lower-quality feedstocks and to determine the optimal process parameters to do so …”

“…A process model of triglyceride hydrolysis could be used to investigate if high-quality fatty acids can be produced from lower-quality feedstocks and to determine the optimal process parameters to do so. 8 In hydrolysis, triglycerides (TG) in the oil react with water to form fatty acids (FA) and glycerol (Gly) After the induction period, the conversion increases rapidly until it flattens and reaches a maximum. 9 Several kinetic models have been proposed for TG hydrolysis.…”

“…A simplified composition is used in which the components are lumped and represented by a set of key components. 8 A detailed composition of the feedstocks is given in Table S5 of the Supporting Information. Table 2 lists the simplified composition used in the model.…”