Enhanced Natural Gas and Methane Conversion intoMethanol in a Membrane Driven Reactor(Experimental Modeling and Simulative Comparisonwith Fixed Catalytic Reactors)

摘要

Modeling and simulative comparison of catalytic permreactors (membrane drivenrnreactors) with fixed plug flow reactors (fixed catalytic reactors) is performed usingrnnumerical analysis techniques, for the synthesis gas (syngas) and methanol productionrnprocesses from methane and natural gas feedstocks. Experimental fixed catalytic reactorsrnare utilized to derive kinetic data for the catalytic methane-steam reforming and the waterrngas shift reactions using combined optimization-integration techniques. Experiments arernalso performed with catalytic membrane reactor modules (permreactors) for comparisonrnpurposes with the fixed catalytic reactors (the syngas to methanol process). The massrnand pressure balances of these reactors were solved numerically to provide the profiles ofrnpartial pressures or molar flowrates or fractional conversions and yields of each speciesrnalong the reactor axial length. Several other reactor parameters were varied in the numerical model to obtain the respective variation of conversion and yield at the reactorrnexit. Such parameters are the reactor temperature and pressure, space time, and reactorrndimensions. The developed numerical reactor models can be also used to predict thernreactors operation at different running conditions in order to increase the syngas andrnmethanol product yield.rnThe methane reforming and shift reactions under analysis are of special interest inrnsyngas and methanol generation and utilization processes. Utilization of improvedrnreactors and reaction systems for methanol production from natural gas is of highrnimportance in the recent fuel, gas, and transportation fuels industry. Methanol is a keyrnfuel and can be directly produced from the synthesis gas which is coming out from therncatalytic reforming of methane or natural gas as described in this paper. Use of methanolrnis mainly in transportation fuels, chemical synthesis, and as fuel in direct methanol fuelrncells (DMFC).rnHydrogen is also a main product from the reforming and related conversionrnreactions. Other hydrogen and syngas utilization processes include feed forrnelectrochemical fuel cells, hydrogen assisted combustion systems, hydrogen richrnhydrotreating of heavy oils, distillates and asphaltenes, chemical synthesis ofrnhydrogenated products (e.g., methanol and olefins).