Sorption-enhanced reaction process with reactive regeneration

Abstract Sorption-enhanced reaction process with reactive regeneration of adsorbent was proposed where the purge step is performed at a low temperature of 400°C (compared with the reaction temperature of 450°C) with 10% H 2 in nitrogen under atmospheric pressure. Hydrogen-enriched stream with traces of CO 2 and CO can be produced by steam–methane reforming. A mathematical model taking into account multicomponent (six species) mass balances, overall mass balance, Ergun relation for the pressure drop, energy balance for the bed-volume element including the heat transfer to the column wall, and nonlinear adsorption equilibrium isotherm coupled with three main reactions was derived to describe this new cyclic process. The feasibility and effectiveness of this cyclic process is analyzed by numerical simulation. The results show that using either a 4 m or a 6 m long adsorptive reactor (depending on the operation time of the first step), a product gas with above 88% hydrogen purity and traces of CO 2 and CO (CO less than 30 ppm ) can be continuously produced and directly used in the fuel cell applications. The validity of the model prediction was checked by comparing the simulated results with experimental data from the literature where the regeneration of adsorbent is carried out by steam purge at subatmospheric pressure. The model results qualitatively agree with experimental data. The package is needed to improve the design and analysis of sorption-enhanced reaction process.

[1]  R. T. Yang,et al.  Gas Separation by Adsorption Processes , 1987 .

[2]  R. Reid,et al.  The Properties of Gases and Liquids , 1977 .

[3]  Robert H. Kadlec,et al.  Equilibrium‐limited periodic separating reactors , 1987 .

[4]  S. Ergun.  Fluid flow through packed columns , 1952 .

[5]  Rutherford Aris,et al.  A continuous chromatographic reactor , 1980 .

[6]  L. Kershenbaum,et al.  Combined reaction and separation in pressure swing processes , 1994 .

[7]  Gilbert F. Froment,et al.  Heat transfer in packed beds , 1972 .

[8]  Douglas M. Ruthven,et al.  Principles of Adsorption and Adsorption Processes , 1984 .

[9]  M. F. Edwards,et al.  Gas dispersion in packed beds , 1968 .

[10]  Jeffrey Raymond Hufton,et al.  Sorption-enhanced reaction process , 1996 .

[11]  D. M. Scott,et al.  Simulation of rapid pressure swing adsorption and reaction processes , 1993 .

[12]  Jeffrey Raymond Hufton,et al.  Production of hydrogen by cyclic sorption enhanced reaction process , 2001 .

[13]  Alírio E. Rodrigues,et al.  Simulation of five-step one-bed sorption-enhanced reaction process , 2002 .

[14]  Bruce A. Finlayson,et al.  Heat transfer in packed beds—a reevaluation , 1977 .

[15]  Yulong Ding,et al.  Adsorption-enhanced steam–methane reforming , 2000 .

[16]  A. Rodrigues,et al.  Pressure swing adsorption reactors: Simulation of three‐step one‐bed process , 1994 .

[17]  R. T. Yang,et al.  Concentration and recovery of carbon dioxide from flue gas by pressure swing adsorption , 1993 .

[18]  Alírio E. Rodrigues,et al.  Propylene/propane separation by vacuum swing adsorption using 13X zeolite , 2001 .

[19]  D. Kunii,et al.  Studies on effective thermal conductivities in packed beds , 1957 .

[20]  L. Kershenbaum,et al.  Enhancement of catalytic reaction by pressure swing adsorption , 1994 .

[21]  G. Froment,et al.  Methane steam reforming, methanation and water‐gas shift: I. Intrinsic kinetics , 1989 .

[22]  Shamsuzzaman Farooq,et al.  Study of a six-bed pressure swing adsorption process , 1997 .

[23]  Jeffrey Raymond Hufton,et al.  Sorption‐enhanced reaction process for hydrogen production , 1999 .

[24]  R. G. Minet,et al.  Packed bed catalytic membrane reactors , 1992 .

[25]  S. Sircar.  Applications of Gas Separation by Adsorption for the Future , 2001 .

[26]  Jeffrey Raymond Hufton,et al.  Sorption enhanced reaction process (SERP) for the production of hydrogen , 1998 .

[27]  Chieh Chu,et al.  Behavior of a Chromatographic Reactor , 1971 .

[28]  Yulong Ding,et al.  Equilibria and kinetics of CO2 adsorption on hydrotalcite adsorbent , 2000 .

[29]  G. G. Vaporciyan,et al.  Periodic separating reactors: Experiments and theory , 1989 .