Biomass is one of the most widely utilized renewable energy sources and is therefore an essential element of sustainable energy production. Different technologies for the direct and indirect utilization of biomass exist. However, biomass is still not fully exploited at its maximum potential, thus further research and development of biomass conversion are necessary. This work aims to offer its contribution to the development of two technologies of focus: torrefaction and gasification. Specifically, the study strives to investigate alternatives to conventional biomass thermo-chemical conversion technologies, namely atmospheric torrefaction and autothermal gasification. A base case thermochemical biomass-to-liquid process, composed of 6 hierarchies is modeled in Aspen Plus for the following sub-systems: torrefaction process, gasification process, quenching, water-gas-shift, acid gas removal, Fischer-Tropsch synthesis and upgrading.