Abstract
|
In this research, effect of water and hydrogen perm-selective membranes via different recycle cases in a
thermally double-coupled two-membrane reactor (TDCTMR) has been investigated. Methanol and direct
dimethyl ether (DME) synthesis from natural gas as exothermic reactions have been thermally coupled
with cyclohexane dehydrogenation as an endothermic reaction. Hydroxy sodalite (H-SOD) and Pd/Ag
membranes have been employed for removing water from methanol side and injection of hydrogen
to DME side respectively. Three different recycle stream cases have been studied for the performance
enhancement of TDCTMR. In the first case, the outlet stream from DME reactor is recycled to itself. Also,
in the second case, the outlet stream from methanol side is recycled toDMEside and finally, the third case
is that the mixture of methanol and DME outlet streams are recycled to DME side. The results of these
three cases are compared with thermally double coupled reactor (TDCR). Results show that hydrogen
production in cyclohexane side of TDCTMR increases 8.32%, 22.89% and 23.88% for cases 1, 2 and 3 in
comparison to TDCR respectively. Also, DME and methanol production enhances 38.38% and 13.3% for
case 3 (best case) in comparison to TDCR respectively.
|