Supercritical Adiabatic Reactor for Fischer-Tropsch Synthesis

Fischer-Tropsch synthesis (FTS) allows for the synthesis of fuels and chemicals from syngas. The reaction is highly exothermic, with the removal of the generated heat being a central consideration in the reactor design. Traditionally, low temperature Fischer-Tropsch synthesis (LTFT) has been carried out under gas-phase conditions (GP-FTS) in a fixed bed reactor or a slurry phase reactor (SP-FTS). Supercritical Fischer-Tropsch (SC-FTS) offers an interesting alternative to traditional Fischer-Tropsch operation. In addition to the many performance benefits of SC-FTS that have been previously documented, the presence of the supercritical solvent provides a diluent effect that greatly reduces the adiabatic temperature rise of the process, making adiabatic operation possible under supercritical fluid conditions. In this work, the technical viability of adiabatic operation for supercritical Fischer-Tropsch is examined. Additionally, preliminary designs of supercritical adiabatic reactor (SCAR) systems, a series of modules each consisting of an adiabatic reactor and a heat exchanger, have been completed, and their capital costs were estimated. The capital cost of this reactor design concept compares very favorably with conventional reactor designs and allows for much easier catalyst replacement and greater reactor control/flexibility than the traditional ARGE reactor.