Travail de fin d'études: "Environmental impact assessment"

Abstract

This research aimed to find the routes for the production of bio-phenol and make a comparison with the use of consequential life cycle assessment, to distinguish the best pathways from an environmental performance point of view. Due to the time limitation, and infancy of the technologies studied, the work still shows potential for further improvements. Initially, different possibilities were studied to find alternatives to the petrol-based phenol. These options were categorized into lignin-first and bio-oil pathways. For each of these categories, sub-groups were found, and more specifically, RCF, AAF, and organosolv were presented as three lignin-first methods. Both for the lignin-first and bio-oil scenarios, the process flow was found through literature review and based on previous works conducted in the field. After development and assessing various possibilities, RCF and bio-oil scenarios were selected to be further studied, and to conduct the LCA for these methods. Next, the detailed process flow was identified for each, followed by the mass and energy balances for both. Biomasses were selected based on the previous works, which are birch, willow, and poplar. LCI was done and needed information were gathered and completed so that the impact assessment could be done. After completion of the process development and LCI step, the modelling was done through activity browser. Six impact categories were studied including: Global Warming Potential (GW100), eutrophication: marine, eutrophication: fresh water, land use, water use, and particulate matter. For all these impact categories, the results are presented for all the biomasses. Among the 6 impact categories studied here, Biomass cultivation and RCF reaction were the ones that appeared as the main contributors three and two times, respectively. Based on table3, these two steps are considered as the hot spots of the process, and further works can be done to improve their environmental impacts. RCF reaction is still not very well-developed and thus, further research and studies are needed to make the process more efficient and less polluting. One of the key conclusions from this work is that (as shown in the result), there is no meaningful difference from an environmental performance point of view between birch, poplar, and willow when they are used as the raw material for RCF process.