process modeling

Direct catalytic oxidation of methane to methanol is a novel technique which has eliminated the intermediate and expensive process of synthesis gas production. This technology can be used for low deposit, remote, low-pressure fields, and abundant resources of unconventional gas, without need to manufacture of expensive units of gas-to-liquid (GTL) process. In present study, modeling and simulation of the single step (direct) conversion of methane to methanol has been investigated in a fluidized-bed reactor packed with V2O5/SiO2 particles as the reaction catalyst. Firstly, the reactor was simulated at steady-state conditions and the effect of important parameters such as feed temperature and residence time of reactants within the reactor on methane conversion and product's selectivity was studied. In the next step, dynamic simulation of the process was performed and the effect of disturbances of effective parameters on reactor performance was investigated. In steady state conditions, for the residence time of 9 seconds maximum yield of methanol production was obtained at 50 bar and 773 K and methane conversion was 32.2 and methanol selectivity was 42.1. Results showed that by increasing reactor temperature and residence time, methane conversion increases but methanol selectivity decreases. Cooling fluid temperature and residence time were found to have the greatest effect on reaction rate and rector performance. Also results showed reasonable agreement with the experimental data reported in the literature for fixed-bed reactor.