Simulation and Control of Steam Reforming of Natural Gas—Reactor Temperature Control Using Residual Gas

Abstract

The present work discusses the mathematical modeling and the control design of the steam reforming of natural gas. The developed model comprises a set of differential and algebraic equations, based on energy and mass balances for reactions performed in a fixed catalyst bed reactor, where natural gas and water are transformed mainly into a mixture of hydrogen and carbon oxides. Normally, after removal of hydrogen and purification of the output stream, the residual gas can be also directed to the furnace to provide heat to the reactor. This is a common practice in industrial sites in order to minimize losses. As the global reactions are exothermic, the reactor temperature may reach prohibitive high values, leading to coke formation and catalyst deactivation. For this reason, a control scheme is proposed to account for regulation of the reactor outlet temperature, using residual and fuel gas streams as manipulated variables, allowing the analysis of effect of several process variables in reactor performance. The obtained results indicate that the proposed mathematical model can accurately represent the steam reforming process and that the proposed control scheme can allow for efficient operation of the reactor, even when the residual gas stream is not sufficient to reach the desired operation temperature.

Computational fluid dynamics modeling of the millisecond methane steam reforming in microchannel reactors for hydrogen production

“…7,8 In contrast, the rate of the steam reforming reaction of methane is relatively slow. 5,6 Interestingly, microfabrication techniques offer new opportunities for the development of methane steam reforming at short contact times. [9][10][11][12] The rapid, efficient conversion of methane to synthesis gas shows great promise for fuel cell applications.…”

“…[1][2][3][4] In industry, synthesis gas is produced by steam reforming of natural gas. 5,6 This reaction is endothermic in nature and requires additional heat to proceed. Therefore, this process is carried out in multi-tubular xed-bed reactors inserted into a large furnace to supply the heat required.…”

RETRACTED: Production of Hydrogen by Methane Steam Reforming Coupled with Catalytic Combustion in Integrated Microchannel Reactors

“…There has been an increasing interest in the development of synthesis gas production due to its potential applications in both fuel cells [1,2] and internal combustion engines [3,4]. The steam reforming of natural gas has become the popular synthesis gas production method in the industry [5,6]. This reaction is usually carried out in multi-tubular fixed-bed reactors inserted into large gas-fired furnaces to supply the necessary energy.…”

“…This reaction is usually carried out in multi-tubular fixed-bed reactors inserted into large gas-fired furnaces to supply the necessary energy. The process is operated under high pressure over a commercial nickel-based catalyst with contact times exceeding one second [5,6]. In recent years, there has been an increasing interest in the production of hydrogen by nuclear-heated steam reforming of methane [7,8].…”

“…The technology of catalytic partial oxidation also offers a promising reaction pathway for the rapid production of hydrogen from methane [9,10]. In contrast, the rate of methane steam reforming reaction is usually considered to be slow [5,6]. Interestingly, millisecond kinetics for this reaction have been documented [11][12][13][14].…”