Mitigation of inhibitors generated in the pre-treatment of vegetal biomass: technical-economic-environmental impact of different processing routes in the biorefinery

Abstract

The implantation of large-scale conversion of lignocellulosic biomass into biofuels and other bioproducts still has technological challenges related to the pretreatment process. At this step, high amounts of inhibitors of the subsequent biochemical reactions are released, notably phenolic compounds and furaldehydes. Hence, strategies to mitigate and/or block the negative effect of the inhibitors from the pretreatment of lignocellulosic material are essential to reduce costs related to enzyme replacement and low fermentation efficiency in the production of bioethanol within the the biorefineries. The inclusion of a biomass washing step and/or the use of additives to reduce the unproductive adsorption of enzymes in the residual lignin are alternatives to optimize the production of second generation (2G) ethanol. However, there are no studies that compare the technical-economic-environmental impact of these alternatives in the bioprocesses of an integrated biorefinery. In this context, the innovation of this doctorate concerns the evaluation of the techno-economic impact on the production of bioethanol in biorefineries in light of the mitigation of the negative effect of inhibitors through different strategies, such as washing and using additives. The reverse analysis of the techno-economical viability of processes based on simulations in EMSO® software was developed by LaDAbio will be applied in this doctorate, since it allows to define performance goals, as well as providing support for the analysis of environmental impacts within the context of an integrated biorefinery biodiesel-bioethanol 1G-2G. Therefore, this project is linked to the thematic project of the BIOEN/FAPESP program: "From the cellular plant to the integrated biorefinery biodiesel-bioethanol: a systemic approach applied to complex problems in micro and macro scales" (proc. 2016/ 10636-8), in the research line 1. The results of this doctorate will define the best inhibitor mitigation strategy that corresponds to the techno-economic viability of the biorefinery with the discussion of environmental sustainability versus water consumption. (AU)