Abstract:
Nowadays, most reactions in chemical and petrochemical industries are catalytic due to their
enhanced effectiveness and reduced product cost. A packed-bed reactor is one of the most
widely used type of the catalytic reactors. However, the packed-bed reactor has several
disadvantages such as possible formation of hot spots in the reactor leading to catalyst
deactivation, non-uniform reactant consumption, and risks of runaway and even explosion
as well as structural maldistribution of catalyst pellets with low packing density close to the
reactor wall and high density in the reactor center resulting in partial bypassing of reactants.
A membrane reactor is the promising alternative to conventional packed-bed reactor. The
membrane reactor combines the separation and chemical reaction processes in one unit. The
permselective membranes are used for selective input of reactant or removal of product that
can permeate through the membrane along the reactor length and as the catalyst support.
This study is focused on modeling the partial oxidation of the methane process in the
membrane packed-bed reactor. Nowadays, the production of synthesis gas from natural gas
becomes more and more important in chemical and petrochemical industries. Currently,
steam reforming is the most commonly used process of syngas production. However, this
process consumes a large amount of energy because it involves highly endothermic and
relatively slow reactions. One of the promising alternatives for hydrogen production is the
partial oxidation of methane. The advantage of this reaction is the possibility to conduct
the process in the smaller reactor due to faster oxidation. The partial oxidation of methane
is a mild exothermic process carried out at high pressure and in the temperature range of
750 – 1200 K. Usually, pure oxygen is used as a source of oxidation and application of the
membrane for selective supply of oxygen by separation from air could decrease the energy
demand and the capital cost of the process significantly. In this research, a 2D non-isothermal model was derived for the packed-bed membrane
reactor, a numerical algorithm was elaborated to solve the model equations, and the python
software was developed to simulate the reactor performance. In addition, the parametric
study was conducted to evaluate the effects of various parameters on the reactant consumption,
product selectivity and yield in the partial oxidation of methane. Finely, it was possible
to determine the process and reactor parameters enabling to achieve a similar performance
of the membrane packed-bed reactor and the conventional packed-bed reactor.