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Catalysis and Reaction Engineering Commons™
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- Catalysis and Reaction Engineering (11)
- Reverse-flow reactors (4)
- Chemical reactors (3)
- Catalytic combustion (2)
- Coal gasification (2)
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- Combustion (2)
- Dynamic simulation (2)
- Heat recovery (2)
- Hydrogen separation (2)
- Mathematical model (2)
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- Mathematical modelling (2)
- Membrane reactors (2)
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- Synthesis gas production (2)
- WGS reaction (2)
- Reverse-flow reactors; (1)
- Asymmetry (1)
- Catalytic reators (1)
- Combustion; Dynamic simulation (1)
- Flow reversal Reactors (1)
- Homogeneous combustion (1)
- Homogeneous methane combustion (1)
- Internal heat recovery (1)
- Intraparticle difusion (1)
- Kinetics (1)
- Methane (1)
- Methane combustion (1)
- Mine ventilation air (1)
- Monolith packing (1)
Articles 1 - 14 of 14
Full-Text Articles in Catalysis and Reaction Engineering
Catalytic Or Thermal Reversed Flow Combustion Of Coal Mine Ventilation Air Methane: What Is Better Choice And When?, Krzysztof J. Gosiewski
Catalytic Or Thermal Reversed Flow Combustion Of Coal Mine Ventilation Air Methane: What Is Better Choice And When?, Krzysztof J. Gosiewski
Krzysztof Gosiewski
The paper presents a comparison of the two options of reverse flow reactors destined for the utilization of coal mine ventilation air methane by catalytic (CFRR) or thermal (TFRR) combustion. It has been shown that both solutions have advantages and drawbacks. The use of the catalyst significantly decreases reactor temperature and makes the operation becomes to be autothermal for methane concentrations lower than in TFRR (even as low as over 0.06 vol.%). On the other hand when methane is combusted, particularly if average concentration is higher than ca. 0.4 vol.% the maximum temperature in the reactor appears to be too …
Applicability Of Membrane Reactor For Wgs Coal Derived Gas Processing: Simulation-Based Analysis, Krzysztof J. Gosiewski, Marek Tanczyk
Applicability Of Membrane Reactor For Wgs Coal Derived Gas Processing: Simulation-Based Analysis, Krzysztof J. Gosiewski, Marek Tanczyk
Krzysztof Gosiewski
Gas from coal gasification contains less hydrogen than from other syngas production methods. An attractive option is its further hydrogen enrichment for pure hydrogen production in a membrane reactor (MR) by Water Gas Shift (WGS). The goal of present study was to analyse MR fed with coal derived gas. Simulations for feasible membrane permeation parameters revealed that to get high conversion above 90% a relatively high S/C should be applied. Moreover, hydrogen recovery is in this case low (below 30%) so for hydrogen production an additional H2 separation after the MR should have been applied. The paper also shows that …
Mathematical Simulation Of Wgs Membrane Reactor For Gas From Coal Gasification, Krzysztof J. Gosiewski, Krzysztof Warmuzinski, Marek Tanczyk
Mathematical Simulation Of Wgs Membrane Reactor For Gas From Coal Gasification, Krzysztof J. Gosiewski, Krzysztof Warmuzinski, Marek Tanczyk
Krzysztof Gosiewski
Mathematical model of a membrane reactor for the water-gas-shift (WGS) reaction and results of simulation studies are presented. The physicochemical phenomena and brief description of the model are given. Due to the fact that membranes for CO2 separation exhibit poor selectivity at the elevated temperature range (indispensable for the desired activity of WGS catalysts), the simulations were carried out only for H2 selective membranes, containing Pd or its alloys. Comparison of the conventional two-stage WGS reactor with the membrane reactor revealed that operating temperature range of the catalyst used in the membrane reactor unit has to be much wider than …
A Study On Thermal Combustion Of Lean Methane–Air Mixtures: Simplified Reaction Mechanism And Kinetic Equations, Krzysztof Gosiewski, Anna Pawlaczyk, Krzysztof Warmuzinski, Manfred Jaschik
A Study On Thermal Combustion Of Lean Methane–Air Mixtures: Simplified Reaction Mechanism And Kinetic Equations, Krzysztof Gosiewski, Anna Pawlaczyk, Krzysztof Warmuzinski, Manfred Jaschik
Krzysztof Gosiewski
Homogeneous combustion of lean methane–air mixtures occurs in both thermal and catalytic reverse-flow reactors. The modeling and design of such reactor requires a reliable and relatively simple kinetic model of the combustion. Although a number of detailed descriptions of the kinetics of homogeneous combustion are available in the literature (including those which take into account complex free-radical reactions), their practical usefulness is doubtful. In the present study a simple one- or two-stage model is proposed which directly describes global kinetics and neglects intermediates and radicals. Special attention is paid to the mechanism of the possible formation of carbon monoxide. The …
Homogeneous Vs. Catalytic Combustion Of Lean Methane—Air Mixtures In Reverse-Flow Reactors, Krzysztof Gosiewski, Yurii Sh. Matros, Krzysztof Warmuzinski, Manfred Jaschik, Marek Tanczyk
Homogeneous Vs. Catalytic Combustion Of Lean Methane—Air Mixtures In Reverse-Flow Reactors, Krzysztof Gosiewski, Yurii Sh. Matros, Krzysztof Warmuzinski, Manfred Jaschik, Marek Tanczyk
Krzysztof Gosiewski
To carry out a comparative assessment of a recently proposed idea of using thermal flow-reversal reactors (TFRR) for mine ventilation air, the results for the catalytic flow-reversal reactor (CFRR) investigated within the European Project (2003) are briefly presented. Next, experimental investigations of thermal combustion are presented in this paper. These consisted of the kinetic study of homogeneous combustion in the pelletized bed and in the monolith. Kinetic equations for the two cases are derived and discussed. Experimental autothermal reverse-flow operation in a laboratory setup was performed. Due to the high heat capacity of the wall and insulation of the pelletized …
Effect Of The Mode Of Heat Withdrawal On The Asymmetry Of Temperature Profiles In Reverse-Flowreactors. Catalytic Combustion Of Methane As A Test Case, Krzysztof Jan Gosiewski, Krzysztof Warmuzinski
Effect Of The Mode Of Heat Withdrawal On The Asymmetry Of Temperature Profiles In Reverse-Flowreactors. Catalytic Combustion Of Methane As A Test Case, Krzysztof Jan Gosiewski, Krzysztof Warmuzinski
Krzysztof Gosiewski
Results of simulations are presented concerning a reverse-flow reactor for the catalytic combustion of methane that occurs in coal-mine ventilation air. Two variants of heat withdrawal are analysed. The simulations show that a relation exists between the method for heat withdrawal and the asymmetry in the profiles of the catalyst temperature over half-cycles of flow reversal. Too strong asymmetry impairs the efficient utilization of the heat produced. The results reveal that the recovery of heat by hot gas withdrawal from the central part of the reactor, and then, the introduction of the gas into a boiler wherein it is cooled …
Efficiency Of Heat Recovery Versus Maximum Catalyst Temperature In A Reverse-Flow Combustion Of Methane, Krzysztof Gosiewski
Efficiency Of Heat Recovery Versus Maximum Catalyst Temperature In A Reverse-Flow Combustion Of Methane, Krzysztof Gosiewski
Krzysztof Gosiewski
Results of simulations are presented concerning a reverse-flow reactor for the catalytic combustion of methane that occurs in coal-mine ventilation air. The simulations were performed for two types of catalyst: 12% MnO2/-Al2O3 and 0.5% Pd/-Al2O3. A special attention is given to maximum temperature of the catalyst bed in order to minimize occurrence of homogeneous combustion. The simulations revealed that there is a visible contradiction between efficiency of heat recovery aimed to high-pressure steam production and efforts to constraint maximum temperature in the bed.
Effective Approach To Cyclic Steady State In The Catalytic Reverse-Flow Combustion Of Methane, Krzysztof Gosiewski
Effective Approach To Cyclic Steady State In The Catalytic Reverse-Flow Combustion Of Methane, Krzysztof Gosiewski
Krzysztof Gosiewski
Computer-based simulations of a reverse-flow reactor should be carried out till the attainment of the so-called cyclic steady state. Usuallythis state is achieved bythe method of direct dynamic simulations. In the paper of Unger et al. (Comput. Chem. Eng. 21 (1997) 5167.) special approaches, making use of various minimization algorithms based most often on Newton algorithms, are proposed. In the present paper one deals with a comparison and an appraisal of these methods, applied to the reverse-flow catalytic combustion of methane that occurs in coal-mine ventilation air.
Simulations Of Non-Stationary Reactors For The Catalytic Conversion Of Methane To Synthesis Gas, Krzysztof Gosiewski
Simulations Of Non-Stationary Reactors For The Catalytic Conversion Of Methane To Synthesis Gas, Krzysztof Gosiewski
Krzysztof Gosiewski
Mathematical simulation results are compared for several types of reactors for the conversion of methane to synthesis gas via catalytic partial oxidation of methane coupled with the simultaneous steam reforming. The simulations concerned reactors operating under non-stationary conditions, i.e. at a continuous, forced unsteady state. Both reverse-flowreactors with pelletized and monolith catalyst were simulated, and those with the pelletized catalyst, operating under conditions of feed composition cycling. The simulation results were compared with data for similar reactors operating at steady state. The basic process parameters compared include the conversion of methane and oxygen and the selectivities of the products (CO …
Mathematical Simulations Of Reactors For Catalytic Conversion Of Methane To Syngas With Forced Concentration Cycling, Krzysztof Gosiewski
Mathematical Simulations Of Reactors For Catalytic Conversion Of Methane To Syngas With Forced Concentration Cycling, Krzysztof Gosiewski
Krzysztof Gosiewski
In this paper simulation results are presented concerning the partial catalytic oxidation of methane (PCOM) in a reactor with forced composition cycling and packed with a pelletized Pt/MgO catalyst. The reactor operates in two cycles, namely, the ‘hot’ cycle, H, during which mainly the reactants of the strongly exothermal complete combustion reaction (CH4 and O2) are supplied, and the ‘cold’cycle , C, in which mainly the components of the endothermal reforming reactions are introduced (CH4 and H2O or, optionally CO2). The simulations are supplemented with a thermodynamic analysis of the conditions of permanent carbon deposits forming in such a reactor. …
Efect Of The Intraparticle Mass Transport Limitations On Temperature Profiles And Catalytic Performance Of The Reverse-Flow Reactor For The Partial Oxidation Of Methane To Synthesis Gas, Krzysztof Gosiewski, Ulrich Bartmann, Marek Moszczynski, Leslaw Mleczko
Efect Of The Intraparticle Mass Transport Limitations On Temperature Profiles And Catalytic Performance Of The Reverse-Flow Reactor For The Partial Oxidation Of Methane To Synthesis Gas, Krzysztof Gosiewski, Ulrich Bartmann, Marek Moszczynski, Leslaw Mleczko
Krzysztof Gosiewski
A mathematical model of the reverse-flow reactor for the catalytic conversion of methane to synthesis gas is presented. The model contains 8 partial diferential equations and 6 algebraic equations. The analysis performed and the literature data suggest a considerable in#uence of the difusional resistance in the catalyst pellet upon the actual rate of reactions occurring in the process. A simple approximate procedure is developed for the estimation of the efectiveness factor of the reactions, which enables the resistance due to internal difusion to be taken into account at any point of the reactor without resorting to numerical integration of the …
Studies Of Multitubular Reactors With Internal Heat Recovery. Experiments With So2 Oxidation, Krzysztof Gosiewski, Ryszard Sztaba, Marek Moszczynski
Studies Of Multitubular Reactors With Internal Heat Recovery. Experiments With So2 Oxidation, Krzysztof Gosiewski, Ryszard Sztaba, Marek Moszczynski
Krzysztof Gosiewski
The paper presents results of investigations of a multitubular reactor with internal heat recuperation. The results obtained were similar to those occuring in the reverse-flow reactors.
Dynamic Modelling Of Industrial So2 Oxidation Reactors Part I. Model Of ‘Hot’ And ‘Cold’ Start-Ups Of The Plant, Krzysztof J. Gosiewski
Dynamic Modelling Of Industrial So2 Oxidation Reactors Part I. Model Of ‘Hot’ And ‘Cold’ Start-Ups Of The Plant, Krzysztof J. Gosiewski
Krzysztof Gosiewski
The paper describes a comparison of some results computed using a mathematical dynamic model of a single reactor bed with real temperature unsteady state transients, measured in a large industrial scale SO2 oxidation reactor. Problems of the dynamic modelling of complete oxidation plants, including a heat exchange section and a start-up installation are discussed in the next section of the paper. As a basis for comparison some start-up dynamic transients were analysed. Tha analysis shows that the model (two-phase model for heat transfer and homogeneous model for mass transfer) is sufficient for qualitative analysis of the problem. The problems of …
Dynamic Modelling Of Industrial So2 Oxidation Reactors Part Ii. Model Of A Reverse-Flow Reactor, Krzysztof J. Gosiewski
Dynamic Modelling Of Industrial So2 Oxidation Reactors Part Ii. Model Of A Reverse-Flow Reactor, Krzysztof J. Gosiewski
Krzysztof Gosiewski
The results are presented of a computer simulation of a reverse-flow reactor. The results are compared with experimental data quoted by other workers. The necessity to take into account gas-to-catalyst heat transfer is stressed, so that quantitatively correct predictions may be obtained using the model. A brief description is given of the way flow reversal has been incorporated in the model, and the possibility of the accumulation of errors occurring during the calculations is mentioned. It is shown that the one-dimensional heterogeneous model of the bed makes it possible to analyze the process with an accuracy sufficient for the preliminary …