Transient discrete-granule packed-bed reactor model for thermochemical energy storage

Abstract An up-flow anaerobic packed bed (UAPB) bioreactor has been designed on a laboratory-scale and used for treatment of domestic milk wastewater (MWW). The UAPB bioreactor was operated under mesophilic temperature (37-45°C) and reactor performance evaluated at various organic loading rates of MWW effluent at hydraulic retention times (HRT) of 1, 2, and 3 d based on the removal of organic matter COD, BOD, SS, pH changes and biogas production. The kinetic parameters were estimated using the experimental data to develop a reactor model. Empirical relations were generated for the characteristics like COD, BOD, and SS using modeling equations. This study proved that the UAPB reactor performance is excellent for treating domestic MWW and easily biodegradable dairy wastewater influent. Hence, this system can operate at low costs, making it suited for use in the developing countries and rural areas.

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Investigations on thermochemical energy storage based on technical grade manganese-iron oxide in a lab-scale packed bed reactor

Solar Energy ◽

10.1016/j.solener.2017.05.034 ◽

2017 ◽

Vol 153 ◽

pp. 200-214 ◽

Cited By ~ 30

Author(s):

Michael Wokon ◽

Andreas Kohzer ◽

Marc Linder

Keyword(s):

Energy Storage ◽

Iron Oxide ◽

Packed Bed ◽

Packed Bed Reactor ◽

Technical Grade

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Modeling and Simulation of the Hydrogenation ofα-Methylstyrene on Catalytically Active Metal Foams as Tubular Reactor Packing

International Journal of Chemical Engineering ◽

10.1155/2016/7082381 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Farzad Lali ◽

Felix-Aron Pahner ◽

Rüdiger Lange

Keyword(s):

Bubbly Flow ◽

Experimental Studies ◽

Tubular Reactor ◽

Packed Bed ◽

Hydrogenation Reaction ◽

Experimental Results ◽

Packed Bed Reactor ◽

Orthogonal Collocation ◽

Reactor Model ◽

Catalytically Active

This work presents a one-dimensional reactor model for a tubular reactor packed with a catalytically active foam packing with a pore density of 30 PPI in cocurrent upward flow in the example of hydrogenation reaction ofα-methylstyrene to cumene. This model includes material, enthalpy, and momentum balances as well as continuity equations. The model was solved within the parameter space applied for experimental studies under assumption of a bubbly flow. The method of orthogonal collocation on finite elements was applied. For isothermal and polytropic processes and steady state conditions, axial profiles for concentration, temperature, fluid velocities, pressure, and liquid holdup were computed and the conversions for various gas and liquid flow rates were validated with experimental results. The obtained results were also compared in terms of space time yield and catalytic activity with experimental results and stirred tank and also with random packed bed reactor. The comparison shows that the application of solid foams as reactor packing is advantageous compared to the monolithic honeycombs and random packed beds.

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A Scalable Silicon Micro-Reactor for Preferential CO Oxidation With an Integrated Platinum Heater

Advanced Energy Systems ◽

10.1115/imece2005-81497 ◽

2005 ◽

Cited By ~ 1

Author(s):

Amit Dhingra ◽

Hong G. Im ◽

Sujit Srinivas ◽

Erdogan Gulari

Keyword(s):

Fuel Cell ◽

Co Oxidation ◽

Packed Bed ◽

Critical Issue ◽

Thermal Design ◽

Packed Bed Reactor ◽

Design Parameters ◽

Reactor Model ◽

Preferential Co Oxidation ◽

Micro Reactor

Recent advances in PEM fuel cell systems have demonstrated their role in the production of clean and efficient power. However, due to complexities and safety concerns in the storage and transport of hydrogen, development of on-board fuel processing of hydrocarbon into hydrogen is being considered a critical issue in the success of the fuel cell technology in transportation application. In this paper, a novel concept of scalable silicon micro-reactor with an integrated platinum heater is developed for preferential CO oxidation. The performance of the micro-reactor is assessed and compared to a packed-bed reactor model. Complementary experimental and modeling efforts are made to identify the optimal thermal design parameters. It is demonstrated that the silicon micro-reactors successfully achieves the objectives of scalability without suffering from loss of efficiency due to the mass transfer limitations.

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Reactor Model for the Underground Coal Gasification (UCG) Channel

International Journal of Chemical Reactor Engineering ◽

10.2202/1542-6580.1351 ◽

2006 ◽

Vol 4 (1) ◽

Cited By ~ 19

Author(s):

Anil N. Khadse ◽

Mohammed Qayyumi ◽

Sanjay M. Mahajani ◽

Preeti Aghalayam

Keyword(s):

Temperature Profile ◽

Coal Gasification ◽

Packed Bed ◽

Packed Bed Reactor ◽

Underground Coal Gasification ◽

Reactor Model ◽

Kinetics Parameters ◽

Transient Model ◽

Composition Profiles ◽

Solid Temperature

Underground Coal Gasification (UCG) is the process of in-situ conversion of coal into combustible products (syngas) which can be used either as fuel or as a chemical feedstock. In this study, the gasification channel is viewed as a one-dimensional packed bed reactor. The packed bed reactor model is solved incorporating chemical reactions and mass transfer effects. A pseudo-transient model is simulated for temperature and composition profiles of the gas and solid phases. The movements of the pyrolysis and the reaction front are obtained. The model results are in qualitative agreement with literature. The effects of various operating parameters are studied in detail. Steam/O2 ratio, inlet O2 and total pressure determine the solid temperature profile and hence the outlet gas composition. The simulations are performed for two sets of kinetics parameters. The solid temperature profile and outlet gas compositions change significantly with a change in kinetics parameters. The main motivation behind this study is to provide a theoretical base for understanding the critical aspects of UCG and to provide a tool which coupled with experiments will help in determining the commercial feasibility of the UCG process.

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Parametric Study of Split Flow Cylindrical Packed Bed Reactor for High-Temperature Thermochemical Energy Storage Using Cobalt Oxide Redox Reaction

Volume 6: Energy ◽

10.1115/imece2019-10956 ◽

2019 ◽

Author(s):

Nasser Vahedi ◽

Alparslan Oztekin

Keyword(s):

High Temperature ◽

Energy Storage ◽

Pressure Drop ◽

Parametric Study ◽

Redox Reaction ◽

Packed Bed ◽

Reactor Design ◽

Packed Bed Reactor ◽

Reactor Performance ◽

Split Flow

Abstract Thermal energy storage has become an integral part of Concentrated Solar Power (CSP) plants to guarantee continuous supply of power demand. For cost-effective solar power generation, the size and operating temperatures of CSP plants should be increased. Thermochemical energy storage (TCES) is the only available solution to meet energy density and high-temperature requirements. Air is mostly used as Heat Transfer Fluid (HTF) for high-temperature CSP plants. For the air-based system, metal redox reactions are good candidates as storage reactant. Application of metal oxide gas-solid redox reaction in storage systems requires an efficient reactor design. Cost-effectiveness and simplicity have made packed bed reactors a viable candidate for high-temperature applications. The high-pressure drop along the bed is the main drawback of such reactors preventing them from widespread applications. Split flow design modification could aid in reducing pressure drop while providing more flexibility in reactor performance control. A cylindrical split-flow packed bed reactor with an annulus for HTF flow is considered as a modified reactor design. The transient two-dimensional axisymmetric numerical model is developed for solving mass, momentum, and energy equations for both gas and solid phases using suitable reaction kinetics for the cobalt oxide redox reaction. A parametric study is performed on cylindrical-shaped split-flow reactor design as a basis for future optimization for complete storage cycle. The effect of split flow ratio and side-channel width on reactor performance are considered. It is shown that both parameters could be used effectively to design and optimize the reactor.

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Modeling of Laboratory Steam Methane Reforming and CO2 Methanation Reactors

Energies ◽

10.3390/en13102624 ◽

2020 ◽

Vol 13 (10) ◽

pp. 2624 ◽

Cited By ~ 3

Author(s):

Paola Costamagna ◽

Federico Pugliese ◽

Tullio Cavattoni ◽

Guido Busca ◽

Gabriella Garbarino

Keyword(s):

Thermal Effects ◽

Packed Bed ◽

Co2 Hydrogenation ◽

Packed Bed Reactor ◽

Methane Reforming ◽

Reactor Model ◽

Co2 Methanation ◽

Steam Methane Reforming ◽

Steam Methane ◽

Mode A

To support the interpretation of the experimental results obtained from two laboratory-scale reactors, one working in the steam methane reforming (SMR) mode, and the other in the CO2 hydrogenation (MCO2) mode, a steady-state pseudo-homogeneous 1D non-isothermal packed-bed reactor model is developed, embedding the classical Xu and Froment local kinetics. The laboratory reactors are operated with three different catalysts, two commercial and one homemade. The simulation model makes it possible to identify and account for thermal effects occurring inside the catalytic zone of the reactor and along the exit line. The model is intended to guide the development of small size SMR and MCO2 reactors in the context of Power-to-X (P2X) studies.

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