Modeling and Optimization of Slurry Reactor in Fischer-Tropsch Synthesis

In recent years, the Fischer-Tropsch synthesis has been considered as an important chemical process for natural gas conversion to liquid fuels. The abundant availability of natural gas and the increasing demand for different hydrocarbon products such as olefins, diesel, and waxes have led to a high level of interest to further develop this process. In this study, a multicomponent reaction engineering model for a slurry bubble column reactor on a commercial scale is developed in order to study the effects of different parameters on product distribution. The modeling results show that different parameters such as temperature, operating pressure, catalyst holdup, and superficial gas velocity affect the syngas conversion and carbon product distribution. In order to maximize the rato of different hydrocarbons products to all the products, the optimization of the operating parameters has been carried out using several optimization techniques such as genetic algorithm (GA), simulated annealing (SA), and gradient method. According to the optimization results, a high H2/CO ratio and low catalyst holdup are required to maximize naphtha, diesel, and wax products relative to the other products. On the other hand, a low H2/CO ratio and high catalyst holdup are required to maximize the olefin products relative to the other products. Moreover, high pressure has a positive impact on the all the products.