edgard.gnansounou The bio-refinery Concept Contacts Process Design and Life Cycle Edgard Gnansounou +41 (0)21 / epfl.ch Laboratory of Energy Systems Station 18 EPFL CH-1015 Lausanne lasen.epfl.ch

LASEN Co-production in Biofuels chains: Potential of the sugar-lignin platform

LASEN Co-production in Biofuels chains: The allocation issue in the bio-refinery concept  Axis 2  Process design and Optimization  Rigorous material and energy balances are needed to improve LCA outputs and relevance and cost estimation  Production function is no necessarily linear  An multi-parameter optimization approach is needed regarding biomass composition, technological configurations, mass transfer and kinetics constraints A bio-refinery is a process in which biomass conversion leads to a multifunctional system including fuels, value added chemicals and power generation. Axis 1 Allocation  In the LCA framework, the allocation of environmental burdens between co-products becomes crucial  Production volume, function and market value varies greatly among co-products making difficult allocation  Some bio-refinery products does not have an established market

LASEN Allocation Strategies StrategyCharacteristicsPertinence Subdivision  Reduces system complexity by separate it into sub- processes.  Generally it is not possible to completely avoid allocation  Sub-processes must be separated in space or in time. System expansion (allocation by substitution)  Recommended by ISO as a first choice method to avoid allocation  Consist of assigning to the co-products environmental burdens of products with equivalent functions  Function equivalent products do not necessarily have equal environmental burdens.  Introduces uncertainty into LCA ( ad infinitum substitution).  Must include dynamic market evolution (consequential LCA) Allocation by physical properties  According to ISO allocation must be done based in physical causalities when it is not possible to avoid it.  Consists of determining factors to distribute environmental burdens between co-products according to a selected physical property (mass, energy content, carbon contents)  Easy interpretation and implementation  Restricted to process where all co-products have similar function, i.e. energy content when all co-products are used as fuels  Weight-based allocation could favor biofuels with high volume of co-products  Is not always straightforward to determine a direct correlation with selected physical property Allocation by economic value  Consist of determining factors for the distribution of environmental burdens between co-products according to the share on sales volume  It is pertinent if demand and search of profit are considered to be the driving factor for production  If market value is used as the allocation criterion, time dynamics becomes important as in the case of substitution (Price variability, subsidies and other market distortions)  Does not necessarily reflect physical reality.

LASEN Ongoing research and questions  Research Axis 1 Allocation –What allocation method is the most pertinent for a multifunction process as a bio-refinery –Is market value an adequate criterion, when allocation is based on economic principles? –should the social utility of a co-product be used instead of market value for allocation? –What are the trade-offs between improving the significance of LCA conclusions and the operability of the methodology?  Research Axis 2 process design –Develop a Process Design Platform (PDP) to Model Bio-refinery pathways, using process engineering software and optimization algorithms. –Coupling process modeling and optimization with LCA development –Evaluate different technological options to increase functionality of Biofuels production

Laboratory of Energy Systems (LASEN) Station 18 EPFL CH-1015 Lausanne Switzerland