Power-to-fuel conversion based on reverse water-gas-shift, Fischer-Tropsch Synthesis and Hydrocracking: Mathematical modeling and simulation in Matlab/Simulink

Abstract

Defossilization of the transport sector must contribute to the drastic reduction of CO2 emissions within the next three decades to limit global warming. The production of synthetic liquid fuels from CO2, water, and renewable electric energy can be one option. A Power-to-Fuel process is modeled based on Reverse Water-Gas-Shift Reaction, Fischer-Tropsch Synthesis (FTS) and Hydrocracking (HC). Different process configurations are investigated - optional intermediate product separation between FTS and HC, and recycle of unreacted streams (wax, tail gas). For practical application, we suggest direct coupling of FTS and HC, as intermediate product separation improves the liquid fuel yield just by a few percent. Compact processes are particularly important for flexible small-scale plants for decentralized application in the context of the energy transition. Wax recycling improves the liquid fuel yield slightly up to 6%. Gas recycling, however, with a ratio of only 0.4 considerably improves it by almost 80%.