Aviation and maritime biofuels production via a combined thermochemical/biochemical pathway: A conceptual design and process simulation study

Abstract

A combined thermochemical-biochemical Biomass-to-Liquid (BtL) pathway for the production of aviation and maritime liquid fuels is presented. The presence of a semi-commercially proven technology like Dual Fluidized Bed Gasification (DFBG) ensures extended fuel flexibility, syngas of high quality, complete fuel conversion and optimal heat integration while avoiding CAPEX intensive equipment like Air Separation Unit. Then, a twostage biochemical route is proposed: initially syngas fermentation (anaerobic) into acetate and subsequently acetate fermentation (aerobic) into targeted triglycerides (TAGs) that will be finally purified and hydrotreated to form the desired drop-in biofuels. The tolerance of the bacteria to syngas contaminants minimizes the gas cleaning requirements. Moreover, the low-pressure requirements (1-10 bar) along with the mild operating temperatures (30-60°C) reduce drastically the capital and operational cost of the process. In terms of efficiency, the biological process of syngas fermentation inherently has limited side products, a fact that reduces the risk of deactivation of hydrotreatment catalysts. The aim of this study is to develop the process model of this novel biorefinery in Aspen Plus TM and to perform the energy and mass balance calculations of the whole value chain, to determine the appropriate key process specifications and to estimate the production cost of the targeted drop-in biofuels.

Design considerations of an integrated thermochemical/biochemical route for aviation and maritime biofuel production

“…An initial presentation of the investigated novel concept, without the parametric analysis and impact assessment of the present study, has been performed within ECOS 2021 (34 th International Conference on Efficiency, Cost, Optimization, Simulation, and Environmental Impact of Energy Systems) [17], while the feedstock selection was based on a dedicated work presented within GCGW 21 (9 th Global Conference on Global Warming) [22].…”

“…The European project BioSFerA [16,17] has undertaken the realization, technical maturation, and implementation of the mentioned novel concept for the production of dropin biofuels that has never been studied before as a whole. DFBG is a semi-commercially proven technology that has already been tested with a wide variety of different feedstocks, like wood pellets/chips, bark, straw, and sewage sludge [18].…”