Power-to-gas: CO2 methanation in a catalytic fluidized bed reactor at demonstration scale, experimental results and simulation

—In this research, the heat transfer and hydrodynamics of a gas–solid fluidized bed reactor were studied experimentally and computationally. A multi-fluid Eulerian computational model incorporating the kinetic theory for solid particles was developed and used to simulate the heat conducting gas–solid flows in a fluidized bed configuration. Momentum exchange coefficients were evaluated using the Syamlal–O’Brien drag functions. Temperature distributions of different phases in the reactor were also computed. Good agreement was found between the model predictions and the experimentally obtained data for the bed expansion ratio as well as the qualitative gas–solid flow patterns. The simulation and experimental results showed that the gas temperature decreases as it moves upward in the reactor, while the solid particle temperature increases. Pressure drop and temperature distribution predicted by the simulations were in good agreement with the experimental measurements at superficial gas velocities higher than the minimum fluidization velocity. Also, the predicted time-average local voidage profiles were in reasonable agreement with the experimental results. The study showed that the computational model was capable of predicting the heat transfer and the hydrodynamic behavior of gas-solid fluidized bed flows with reasonable accuracy.

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Experiment and numerical analysis of catalytic CO2 methanation in bubbling fluidized bed reactor

Energy Conversion and Management ◽

10.1016/j.enconman.2021.113863 ◽

2021 ◽

Vol 233 ◽

pp. 113863

Author(s):

Son Ich Ngo ◽

Young-Il Lim ◽

Doyeon Lee ◽

Myung Won Seo ◽

Sungwon Kim

Keyword(s):

Numerical Analysis ◽

Fluidized Bed ◽

Fluidized Bed Reactor ◽

Co2 Methanation ◽

Bubbling Fluidized Bed

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Prediction of gas holdup in a combined loop air lift fluidized bed reactor using Newtonian and non-Newtonian liquids

Chemical Industry and Chemical Engineering Quarterly ◽

10.2298/ciceq110401024v ◽

2011 ◽

Vol 17 (3) ◽

pp. 375-383

Author(s):

Sivakumar Venkatachalam ◽

Akilamudhan Palaniappan ◽

Senthilkumar Kandasamy ◽

Kannan Kandasamy

Keyword(s):

Fluidized Bed ◽

Particle Diameter ◽

Fluidized Bed Reactor ◽

Gas Holdup ◽

Operating Conditions ◽

Experimental Results ◽

Gas Velocity ◽

Wide Range ◽

Newtonian Liquids ◽

Superficial Gas Velocity

Many experiments have been conducted to study the hydrodynamic characteristics of column reactors and loop reactors. In this present work a novel combined loop airlift fluidized bed reactor was developed to study, the effect of superficial gas and liquid velocities, particle diameter, fluid properties on gas holdup by using Newtonian and non-Newtonian liquids. Compressed air was used as gas phase. Water, 5% n-butanol, various concentrations of glycerol (60 % and 80 %) were used as Newtonian liquids, different concentrations of Carboxy Methyl Cellulose (0.25 %, 0.6 % and 1.0 %) aqueous solutions were used as non-Newtonian liquids. Different sizes of Spheres, Bearl saddles and Raschig rings were used as solid phases. From the experimental results it was found that the increase in superficial gas velocity increases the gas holdup, but it decreases with increase in superficial liquid velocity and viscosity of liquids. Based on the experimental results a correlation was developed to predict the gas holdup for Newtonian and non-Newtonian liquids for a wide range of operating conditions at a homogeneous flow regime where the superficial gas velocity is approximately less than 5 cm/s.

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Numerical model of biofilm kinetics in a methanogenic fluidized bed

Water Science & Technology ◽

10.2166/wst.1996.0577 ◽

1996 ◽

Vol 34 (5-6) ◽

pp. 411-420

Author(s):

Tsuyoshi Imai ◽

Tetsuya Kusuda

Keyword(s):

Numerical Model ◽

Fluidized Bed ◽

Growth Process ◽

Fluidized Bed Reactor ◽

High Accuracy ◽

Experimental Results ◽

Biofilm Model ◽

Attached Biomass ◽

Specific Activities ◽

Extracellular Polymer

A layered biofilm model which expresses the growth process of biofilm with attrition in a methanogenic fluidized bed reactor is developed based on results of experiment to comprehend distributions of biomass in the biofilm. Availability of the model and the existence of “dormant” biomass in the biofilm are discussed in comparison with the experimental results. Distributions of the active, dormant, and inert biomasses and extracellular polymer in a biofilm are predicted by the model. Comparing specific activities of sloughed and remaining biomasses with those of the attached biomass, the existence of “dormant” biomass in the biofilm is indicated. The model also expresses distributions of specific activities of active and dormant biomasses in the biofilm with high accuracy. The model is applicable to predict the distributions of biomasses in a biofilm under various sloughing conditions.

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