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Membrane Reformer (membrane + reformer)
Selected AbstractsCeramic Supported Capillary Pd Membranes for Hydrogen Separation: Potential and Present LimitationsFUEL CELLS, Issue 6 2006V. Gepert Abstract Composite ceramic capillaries coated with thin palladium membranes are developed for the production of CO-free hydrogen for PEM fuel cells, via alcohol steam reforming. The composite membranes are tested for pure H2 and N2, as well as for synthetic reformate gas. The aim is to develop a heat-integrated compact membrane reformer for decentralized hydrogen production. In this context, a deep knowledge of the performance, behavior, and necessary treatment of the composite palladium membranes plays a decisive role in process design. The current contribution focuses on the main hurdles met while attempting to exploit the potential of ceramic supported capillary palladium membranes. [source] Design of a thermally balanced membrane reformer for hydrogen productionAICHE JOURNAL, Issue 10 2008David S. A. Simakov Abstract Hydrogen production by autothermal methane steam reforming in a catalytic fixed bed membrane reactor has been analyzed and simulated. The two-compartment reactor indirectly couples the endothermic steam reforming with methane oxidation, while hydrogen is separated by a permselective Pd membrane. Simulations of the reactor, using published kinetics, map the acceptable domain of operation and the optimal set of operating parameters. The simulations exhibit slow-moving thermal fronts and the steady-state operation domains bounded by stationary fronts, separating domains of upstream and downstream-moving fronts. Front velocity depends on thermal coupling and hydrogen separation. An analytical approximation for the thermal front velocity in a thermally balanced reactor has been developed. © 2008 American Institute of Chemical Engineers AIChE J, 2008 [source] Novel nickel-based catalyst for low temperature hydrogen production from methane steam reforming in membrane reformerASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 1 2010Yazhong Chen Abstract Hydrogen production from various hydrocarbon fuels, particularly biomass-derived fuels, has attracted worldwide attention due to its potential for application to fuel cells, a device which converts chemical energy into electricity efficiently and cleanly. However, current technology, such as natural gas steam reforming, could not meet the specific requirements of hydrogen for fuel cells. Therefore, novel processes are intensively investigated, aiming to develop economic and efficient ones for the specific purpose. An important direction is the integrated membrane reformer for one-step high-purity hydrogen production. However, for the commercial realization of this technology, there are still some difficulties to overcome. By comparison with previous investigations with a similar membrane, this work showed that catalyst also played an important role in determining membrane reformer performance. We proposed that when thickness of membrane was several micrometers, the permeance of membrane became less important than the kinetics of catalyst, due to the fact that under such conditions, hydrogen permeation rate was faster than the kinetics of steam reforming reaction when commercial catalyst was applied, but further evidence is indispensable. In this initial work, we focused on developing efficient nickel catalyst for low temperature steam reforming. Nickel-based catalyst was developed by deposition,coprecipitation and used as pre-reduced, showing high performance for methane steam reforming at low temperatures and good durability, which may find practical application for the integrated membrane reforming process. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] A simulated auto-thermal membrane reformer process for a PEM fuel cell micro cogeneration unitASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 3 2009Dr. Atilla Ersöz Abstract There are several methods of producing hydrogen-rich gas from fossil resources such as natural gas or naphtha, for example, steam reforming, partial oxidation and auto-thermal reforming. In this paper, an integrated ATR membrane reactor system was simulated. The effect of operating parameters on the product distribution, fuel cell hydrogen utilization and the net electric efficiency of the overall system were discussed. The overall system was integrated with a 1-kWe PEM fuel cell. The ASPEN-HYSIS 3.2 software has been utilized for the simulations and calculations of the fuel processing reactions. Natural gas fuel has been used as feedstock and applied to the simulated flow-sheet model. It was desired to produce hydrogen-rich gas with a low CO formation using an autothermal membrane reformer. A very low CO content with higher content of hydrogen was provided by the membrane reformer, eliminating the use of the conventional preferential oxidation (PrOx) reactor. Different combinations of TATR, S/C, O2/C ratios and UH2 have been parametrically studied. Fuel processing efficiency and net electrical efficiency of all selected operating conditions have been calculated as well. Results indicate that the system parameters are very critical for the appropriate operation of the residential cogeneration system with ATR membrane unit. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Membrane reformer PEM cogeneration systems for residential applications,Part A: full load and partial load simulationASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 3 2009Stefano Campanari Abstract This two-part paper investigates the performances and economic potential benefits of a fuel cell cogeneration system based on a membrane reformer (MREF), using polymer electrolyte membrane (PEM) fuel cells, applied to residential cogeneration. Part A of this work focuses on the thermodynamic analysis and simulation of the system at full and partial load conditions, discussing its performance by means of a sensitivity analysis carried out under different operating conditions. Part B presents the technoeconomic analysis of the proposed system integrated into a real residential application, dealing with the energy savings and the economic balances, and proposes a preliminary design of the cogeneration unit. The system is based upon a PEM fuel cell, integrated with a membrane reformer (MREF) to form a small-scale, highly efficient cogeneration unit, potentially suitable for application to distributed generation in the residential field. The high purity hydrogen fuel required by the PEM fuel cell is produced in the membrane reformer through hydrogen selective membranes based on a Pd-Ag alloy. The analysis is carried out aiming to define the system energy balances in all the conditions occurring under real operation, including the influence of ambient temperature and of the expected fuel cell efficiency decay with time. The discussion reveals the relevant potential advantages of the MREF solution with respect to fuel cell units based on steam reforming (SR) or auto-thermal reforming (ATR): when compared to these solutions, MREF exhibits a 10% points higher electrical efficiency and requires a much simpler plant layout. These results are the basis for the detailed system technoeconomic analysis carried out in Part B of the work. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Membrane reformer PEM cogeneration systems for residential applications,Part B: techno-economic analysis and system layoutASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 3 2009Stefano Campanari Abstract This two-part paper investigates the performances and potential economic benefits of a membrane reformer (MREF)-based fuel cell cogeneration system, using polymer electrolyte membrane (PEM) fuel cells, applied to residential cogeneration. Part A of the work focuses on the thermodynamic analysis and simulation of the system at full and partial load conditions, discussing its performance by means of a sensitivity analysis carried out under different operating conditions. Part B presents the techno-economic analysis of the proposed system integrated into a real residential application, dealing with the energy savings and the economic balances, and proposes a preliminary design of the cogeneration unit. The higher electric efficiency of the innovative MREF system proposed in this work allows a yearly cost savings about 50% higher than cost savings allowed by fuel cell cogeneration units based on conventional fuel processors. Moreover, CO2 emissions savings, calculated for an average northern Italy single-family load, is about 1.6 tCO2/year. The paper also presents a proposed system layout, discussing the preliminary design of all the required components and analyzing with particular care the issues related to the heat recovery loop and to the arrangement of the system key component: the membrane reforming reactor. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] | ||||||||||