Traditionally, the sizing of chemical processes is based on technical and profitability criteria. However, due to growing climate concerns, process optimization must now consider other criteria, as highlighted by Azapagic in 1999. This paradigm shift requires taking into account not only economic viability but also environmental and societal impacts. Consequently, various methodologies have emerged, among which the coupling of process engineering and life cycle assessment (LCA) appears as a promising approach to simulate processes and their impact. Nevertheless, implementing this coupling is challenging for processes developed for biomass fractionation. These processes include unit operations (membrane filtration, chromatography, etc.) that are not as well described as processes like distillation in conventional software such as Aspen^Ó and SuperPro-designer^Ó. Indeed, while membrane modeling has been studied for a long time, the developed models are generally based on the description of mechanisms and are not suitable for simulating the performance of a wide range of membranes. Therefore, in the classical process engineering approach, membrane performance is evaluated based on mass balance and requires experimental data. To address this gap in membrane filtration, it is necessary to have a model capable of simulating results ranging from nanofiltration to microfiltration. The modeling of porous membranes is generally based on Darcy's law, which allows calculating membrane permeability from the pore diameter and membrane thickness. The problems during simulation then arise from the variation in thickness between different types of membranes and the influence of fouling and the concentration polarization layer during filtration.

The objective of this study is to propose a new approach to facilitate the eco-design of biomass fractionation processes by coupling process simulation with ProsimPlus^Ó software and life cycle assessment with SimaPro^Ó software. This approach is illustrated through a case study related to the purification of phenolic compounds by ultrafiltration.

The ProsimPlus^Ó software allows for the simulation and scaling of various chemical engineering processes. Although it is not inherently suited for membrane filtration, it can be adapted by implementing a specific model within a dedicated module. In this study, a model (Equation 1) describing the performance of nanofiltration and ultrafiltration was introduced into ProsimPlus^Ó and used to achieve a comprehensive analysis of technical performance under varying operating conditions. These simulations were linked to SimaPro^Ó to determine the influence of operational conditions on the environmental impact of the unit's operation....

The membrane filtration model was developed based on Darcy's law and modified to account for the effect of concentration polarization and fouling. The model parameters (a et b) were determined from experimental data, and then the model was applied to simulate the influence of pressure on the filtration performance of phenolic compounds by membranes with molecular weight cutoffs ranging from 1 kDalton to 100 kDalton. The influence of operating conditions was validated by experimental results, and then used to assess their impact on the environment by calculating membrane surface area and energy consumption.

The results indicate that...