PROCESS SYSTEMS ENGINEERING Intensified energetically enhanced steam methane reforming through the use of membrane reactors Patricia A. Pichardo | Vasilios I. Manousiouthakis Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, California Correspondence Vasilios Manousiouthakis, Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA 90095. Email: vasilios@ucla.edu Abstract This work focuses on the implementation of membrane reactors (MRs) in the production of hydrogen through steam–methane reforming (SMR). A novel equi- librium MR model featuring Gibbs Free Energy Minimization is introduced and applied to the SMR-MR process. In addition, the concept of “energetically enhanced steam methane reforming (EER),” which allows for the use of a hybrid (methane combustion/renewable energy) energy supply in the production of hydrogen, is intensified. The UNISIM software (Honeywell™) is used to create a range of intensified flowsheets depicting the proposed IEER-MR process as well as two baseline flowsheets depicting “a standard SMR-MR process” and “a fully exothermic EER process.” Heat integration studies are carried out on the devel- oped flowsheets, and the baseline designs are compared to the IEER-MR designs to identify energetic intensification. KEYWORDS design (process simulation), membrane separations, process synthesis 1 | INTRODUCTION The concept of process intensification is currently one of the most important trends in chemical engineering. It has been defined as the development of technology and methods that can produce dramatic improvements in chemical processing. 1 These drastic improvements can consist of substantial decrease in equipment volume, energy con- sumption, or waste formation that can lead to safer, sustainable, and cheaper manufacturing processes. 2 Process intensification (PI) can offer methods of supporting sustainable industrial growth through a variety of tools. Some of these tools include the use of a pinch-like targeting framework that can combine two or more heat sources into a single intensified device aimed at thermal process intensification, 3 and the use of the Infinite DimEnsionAl State-space (IDEAS) concep- tual framework, which has been applied to topics such as reactive distillation systems, 4 and energetically enhanced reforming (EER). 5 Along with these intensification frameworks, is the integration of multi-functional units such as membrane reactors (MRs). MR pro- cesses can be used to attain PI objectives since they have the ability of simultaneous reaction and separation. The study of MR processes’ contribution in the process intensification field has been vastly researched 6 including the intensification of lactic acid production 7 and biodiesel production. 8 MRs combine reaction and separation in one single unit through the removal of, at minimum, one of the species present. Typically, these types of reactors are used when reactions are limited by ther- modynamic equilibrium, since removing at least one of the reacting products through membrane permeation results in an increase in the conversion and yield beyond the limiting equilibrium value. 9 In addi- tion to improving a reaction's yield, MRs can increase the selectivity and yield of enzymatic and catalytic reactions by selectively removing intermediate species that would otherwise deactivate the reaction. 9 MRs have been studied in the production of various materials includ- ing biodiesel, 10 chitooligosaccharides, 11 and hydrogen. 12-16 The pro- duction of hydrogen through the steam-methane reforming (SMR), and water gas shift reactions (WGSR) has been a particular area of interest for MRs. SMR has been carried out in ceramic MRs, 13 Pd coated ceramic MRs, 14 catalytic ceramic membrane reformers, 15 and reactors with Pd composite membranes deposited on porous stainless steel, 16 while WGSR has been carried out in an MR, in the context of Received: 24 February 2019 Revised: 14 August 2019 Accepted: 30 September 2019 DOI: 10.1002/aic.16827 AIChE Journal. 2019;e16827. wileyonlinelibrary.com/journal/aic © 2019 American Institute of Chemical Engineers 1 of 12 https://doi.org/10.1002/aic.16827