Challenges and opportunities of process modelling renewable advanced fuels

The Paris COP21 held on December 2015 represented a step forward global GHG emission reduction: this led to intensify research efforts in renewables, including biofuels and bioliquids. However, addressing sustainable biofuels and bioliquid routes and value chains which can limit or reverse the ILUC (indirect land-use change effect) is of paramount importance. Given this background condition, the present study targets the analysis and modelling a new integrated biomass conversion pathway to produce renewable advanced fuels, enabling the issue of indirect land-use change (ILUC) of biofuels to be tackled. The bioenergy chain under investigation integrates the decentralized production of biogas through anaerobic digestion and its upgrading to biomethane, followed by a centralized conversion to liquid transport fuels, involving methane reforming into syngas, Fischer–Tropsch (FT) synthesis, and methanol synthesis. The methodology adopted in this work stem from extensive literature review of suitable bio/thermo-chemical conversion technologies and their process modelling using a commercial flow-diagram simulation software is carried out. The major significance of the study is to understand the different modelling approaches, to allow the estimation of process yields and mass/energy balances: in such a way, this work aims at providing guidance to process modellers targeting qualitative and quantitative assessments of biomass to biofuels process routes. Beyond FT products, additional process pathways have been also explored, such as MeOH synthesis from captured CO2 and direct methane to methanol synthesis (DMTM). The analysis demonstrated that it is possible to model such innovative integrated processes through the selected simulation tool. However, research is still needed as regards the DMTM process, where studies about modelling this route through the same tool have not been yet identified in the literature.