A CAPE based life cycle assessment for evaluating the environmental performance of non-food agro-processes
Résumé
With the rise of global warming issues due to the increase of the greenhouse gas emission and more generally with growing importance granted to sustainable development, process system engineering (PSE) has turned to think more and more environmentally. Indeed, the chemical engineer has now taken into account not only the economic criteria of the process, but also its environmental and social performances. To evaluate such non-economic performances is challenging and arduous. For this purpose, many approaches could be taken into consideration like environmental impact assessment, environmental impact indices, environmental risk assessment, cost-benefit analysis, life cycle assessment (LCA) and Social LCA. Among these approaches, the coupling of PSE and LCA will be investigated here because it is viewed as a good instrument to evaluate the environmental performance of different unitary processes and whole process. The coupling can be of different nature depending on the focus of the study. Either the study is focused on PSE with an associated LCA study (LCA applied to PSE), or LCA study including mass balance and energy balance (PSE applied to LCA). PSE mainly focuses on design, operation, control and optimization of process with the help of computer based methods i.e. Computer Aided Process Engineering (CAPE). In this study we proceed to an environmental analysis of a non-food agro-process (i.e. biodiesel production from Jatropha) applying our CAPE based LCA proposal. To complement the experimental data the highly impactful unitary processes (i.e. transesterification) is selected for further analysis via simulation. A modelling tool on Microsoft Excel is developed to link LCA and process simulation. For results validation we also implement LCA in a dedicated tool (SIMAPRO) and simulation in a CAPE simulator (ProSim Plus). Furthermore this development of simulation based LCA framework can serve as a step forward for determination of sustainability and eco-efficient designing.