Hollow Fiber Membrane Module For Gas Separation

The potential of membrane technology for the effective separation of carbon dioxide from methane has attracted significant attention over the past decades. Hollow fiber module is the most employed membrane module for gas separation industries with more than 80 percent of market share. In this book, an experimentally validated non-ideal model has been developed and integrated in a process simulator for hollow fiber membrane module, which can be used to evaluate the separation performance and economics of the system. This work was carried out as a part of PhD at Chemical Engineering Department, Universiti Teknologi PETRONAS. This book serves as reference material for students, researchers and engineers working in the field of membrane technology and gas separation.

Computational fluid dynamics simulations are conducted for multicomponent fluid flows over banks of hollow fiber membranes. The hollow fiber membrane systems is considered here for gas separation applications. Separation of carbon dioxide (CO2) from methane (CH4) is studied using hollow fiber membranes packed in different arrangements. The membrane surface is considered as a functional surface where the mass flux and concentration of each species are coupled and are determined as a function of the local partial pressures, the permeability, and the selectivity of the membrane. k-o Shear Stress Transport (k-o SST) turbulent model is employed to study the mixture flow over banks of hollow fiber membrane for values of the Reynolds number up to 1000. The flow structure around the hollow fiber membranes dominates the performance of the separation process. This study demonstrates clearly that good mixing in the bank of hollow fiber membranes enhances the separation performance. The results show that hollow fiber membrane module with staggered arrangement performs much better than that with inline arrangement. For the spiral wound membrane, it has been shown that membrane performance could be greatly enhanced by momentum mixing in the feed channel induced by spacers. Square shaped spacer will be considered in the inline arrangement for values of the Reynolds number up to 500. In order to validate the turbulence model transient flow simulations are conducted using lattice Boltzmann method. The lattice Boltzmann method to simulate flow in the geometries related to the spiral wound membrane modules is developed by our research group at Lehigh. Two dimensional nine velocity directional, D2Q9, lattice arrangement with multi-relaxation time (MRT) lattice Boltzmann method is used to simulate transient flow field while single relaxation time (SRT) lattice Boltzmann method. Simulations are performed to determine concentration field for values of Re up to 300. The bounding surfaces are treated as impermeable walls for simulations conducted using the lattice Boltzmann method. The results predicted by the lattice Boltzmann method and the SST turbulence model agree well, validating the turbulence model and the numerical method.

This two volume set presents the state-of-the-art, and potential for future developments, in membrane engineering for the separation of gases.

Since the development of the first modules, hollow fibers have totally revolutionized the world of membranes—thanks to the new technological breakthroughs and innovative materials discovered. The importance of a book putting hollow fibers in the spotlight owes to this type of configuration being more and more appreciated, particularly in large-scale applications. Moreover, the advent of nanofibers has injected new vitality in biomedical research, air and water separation and filtration processes, and emerging areas of nanotechnology. This book singles out and highlights the unique properties that hollow fibers and nanofibers display in the fields where they already represent the dominant configuration and where their full exploitation is still hindered by economic and technological constraints.

Computational fluid dynamics simulations are conducted for laminar steady asymmetric flows within a hollow fiber membrane unit. The goal is to study the effect of the porous layer of a hollow fiber membrane (HFM) on the flow regimes and thus on the separation process. The mixture of CH4 and CO2 is studied with the goal of separating CO2 from CH4. The hollow fiber membrane consists of a circular channel bounded by a supporting porous layer. Outer surface of the tubular pipe is bounded by a selective membrane. The Navier-Stokes equation, Darcy's law, and the species transport equations are solved for various values of permeability of the porous medium and Reynolds numbers. The mass flux of each species passing through the membrane is determined based on the local partial pressure, the concentration of each species, the permeability and the membrane selectivity. The porous layer influences the flow field in the open channel strongly. With increasing resistance the flow rate through the porous medium decreases. The flow rate through the open channel increases as the resistance of the porous layer is increased. The presence of the porous layer results in the reduction of mass flux of both CH4 and CO2 passing through the membrane. The Sherwood number is reduced at all Re as the resistance of the porous layer is increased. The increased resistance of the porous layer also causes an increase in the pressure drop in the hollow fiber membrane module. The present study proves that the porous layer should be included in modeling of hollow fiber membrane systems.

This book describes the tremendous progress that has been made in the development of gas separation membranes based both on inorganic and polymeric materials. Materials discussed include polymer inclusion membranes (PIMs), metal organic frameworks (MOFs), carbon based materials, zeolites, as well as other materials, and mixed matrix membranes (MMMs) in which the above novel materials are incorporated. This broad survey of gas membranes covers material, theory, modeling, preparation, characterization (for example, by AFM, IR, XRD, ESR, Positron annihilation spectroscopy), tailoring of membranes, membrane module and system design, and applications. The book is concluded with some perspectives about the future direction of the field.

Hollow Fiber Membranes: Fabrication and Applications focuses on the fabrication and applications of hollow fiber membranes. The book amply discusses the fundamental theories and practical applications of hollow fiber membranes, covering membrane formation mechanisms, hollow fiber spinning techniques, and spinneret design and module fabrication. In addition, novel membrane processes and applications of hollow fiber membranes are introduced. Elaborates membrane formation mechanisms Illustrates novel hollow fiber fabrication techniques and processes Specifies practical spinneret design and module fabrication Reviews hollow fiber membranes spun from specialty polymers Discusses state-of-the-art hollow fiber membrane applications

Elaborating on recent and future developments in the field of membrane engineering, Volume 1 focuses on new membrane materials which have recently emerged in gas separation. Covering graphene/graphene oxide based membranes, PIMs, thermally rearranged membranes, and new mixed matrix membranes, alongside membrane pilot plant trials of gas separation, such as CO2 from flue gas and biogas, as well as a cost analysis of competitive membrane and hybrid systems, this book provides a comprehensive account. Together with Volume 2, these books form an innovative reference work on membrane engineering and technology in the field of gas separation and gaseous phase membrane reactors.