Determination of temperature and concentration field in reactor for steam conversion of methane under pressure, with nonuniform radiation to furnace tubes

The paper considers two fractional-differential models of convective diffusion with mass exchange and proposes a decision-making algorithm for determining the optimal model at the time of concentration field observation. As for soils of fractal structure, direct experimental determination of model parameters’ values and type of mass exchange process is in many cases impossible, calibration and determination of the most adequate models is performed mainly solving inverse problems by, in particular, meta-heuristic algorithms that are computationally complex. In order to reduce the computational complexity, we study the qualitative differences between diffusion processes described by fractional-differential models with non-local mass exchange on the base of the Caputo derivative and local non-linear mass exchange based on the non-equilibrium sorption equation that corresponds to the description by the Caputo-Fabrizio derivative. We determine under which conditions both models within a given accuracy describe the same set of measurements at a certain moment of time. When the solutions are close at a certain initial stage of process development, the model with the Caputo derivative describes its faster approach to a steady state. Based on the obtained estimates of differences in solutions, a decision-making algorithm is proposed to determine the most accurate model and the values of its parameters concurrently with the acquisition of measurements. This algorithm’s usage reduces the time spent on solving inverse calibration problems.

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Valorisation chimique du mèthane par plasmas micro-ondes

Canadian Journal of Chemistry ◽

10.1139/v98-199 ◽

1998 ◽

Vol 76 (12) ◽

pp. 1875-1885 ◽

Cited By ~ 3

Author(s):

N Kopytko ◽

F Baronnet

Keyword(s):

Microwave Plasma ◽

Flow Reactor ◽

Experimental Results ◽

Reaction Products ◽

Time Flow ◽

Conversion Of Methane ◽

Tubular Flow Reactor ◽

Tubular Flow ◽

Microwave Techniques

The conversion of methane in a direct microwave plasma was investigated at pressures ranging from 4 to 28 Torr in a tubular flow reactor located in a parallelepipedic Moreau cavity. The main purpose of this work was the determination of the products obtained by methane conversion, especially C2 hydrocarbons. The reaction products were analysed by gas phase chromatography. The influence of various reaction parameters (residence time, flow, pressure, power...) was studied. The experimental results showed that substantial yields in C2 hydrocarbons could be obtained. Our experimental results are compared to those obtained by other processes, especially oxidative coupling and thermal coupling, and also to those obtained by other authors using microwave techniques.

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Data analysis and recommendations for the determination of the equilibrium constant for CO steam conversion and of consumption ratios of ammonia production

Odes’kyi Politechnichnyi Universytet Pratsi ◽

10.15276/opu.3.42.2013.49 ◽

2013 ◽

pp. 243-248

Author(s):

I. A. Slabun ◽

◽

L. L. Tovazhnyansky ◽

V. A. Marshala

Keyword(s):

Data Analysis ◽

Equilibrium Constant ◽

Ammonia Production ◽

Steam Conversion

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Evaluation of efficiency of special-purity hydrogen production from products of steam conversion of methane and its close homologs in high-temperature converter–membrane equipment system using methane or carbon monoxide conversion catalyst

Chemical and Petroleum Engineering ◽

10.1007/s10556-013-9659-y ◽

2013 ◽

Vol 48 (9-10) ◽

pp. 566-575

Author(s):

A. B. Vandyshev ◽

V. A. Kulikov

Keyword(s):

Carbon Monoxide ◽

High Temperature ◽

Hydrogen Production ◽

Steam Conversion ◽

Conversion Of Methane ◽

Conversion Catalyst ◽

Equipment System

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Pressurized Steam Conversion of Biomass Residues for Liquid Hydrocarbons Generation

Energies ◽

10.3390/en14041034 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1034

Author(s):

Francesco Miccio ◽

Elettra Papa ◽

Annalisa Natali Murri ◽

Elena Landi ◽

Matteo Minelli

Keyword(s):

Liquid Fraction ◽

Batch Reactor ◽

Operating Conditions ◽

Nonpolar Solvent ◽

Thermochemical Conversion ◽

Liquid Hydrocarbons ◽

Steam Conversion ◽

Biomass Residues ◽

Alternative Feedstock

Biomass residues are often considered as a resource if conveniently converted in fuel and alternative feedstock for chemical processes, and their conversion into valuable products may occur by different pathways. This work is focused on the thermochemical conversion at moderate temperature and in steam atmosphere, a mild process in comparison to hydrothermal liquefaction, followed by extraction of soluble products in a solvent. Such process has been already applied to various residues and here extended to the case of marc, the residual pomace from wine making, largely produced worldwide. A pressurized batch reactor was used for the quantitative determination of produced solid and liquid fractions, and their qualitative characterization was performed by instrumental analyses. The pressurized steam conversion of marc was effective, providing a yield in liquid fraction, upon extraction in solvent, up to 30% of the raw dried biomass. The use of polar and nonpolar solvent for the extraction of the liquid fraction was inspected. Applied operating conditions, namely residence time in the batch reactor and extraction modality, showed a significant influence on the process performance. In particular, long residence and extraction times and use of nonpolar solvent substantially improved the yield in liquid fraction.

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