Unsteady-state methanation of carbon dioxide in a fixed-bed recycle reactor — Experimental results for transient flow rate ramps

Matthischke, Steffi; Krüger, Raphael; Rönsch, Stefan; Güttel, Robert

doi:10.1016/j.fuproc.2016.07.021

Cited by 47 publications

(37 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reactor is heated to 300°C in a furnace. A high methane yield of 88.4% is obtained at 0.18 MPa with a GHSV of 2573 h −1 and a maximal temperature of 455°C . At a similar GHSV (2800 h −1 ), Ducamp shows that, in a wall‐cooled annular fixed‐bed reactor, a high yield of methane is also experimentally obtained.…”

Section: Resultsmentioning

confidence: 79%

Dynamic modeling and simulations of the behavior of a fixed‐bed reactor‐exchanger used for CO₂ methanation

et al. 2017

View full text Add to dashboard Cite

A multidimensional heterogeneous and dynamic model of a fixed-bed heat exchanger reactor used for CO 2 methanation has been developed in this work that is based on mass, energy and momentum balances in the gas phase and mass and energy balances for the catalyst phase. The dynamic behavior of this reactor is simulated for transient variations in inlet gas temperature, cooling temperature, gas inlet flow rate, and outlet pressure. Simulation results showed that wrong-way behaviors can occur for any abrupt temperature changes. Conversely, temperature ramp changes enable to attenuate and even fade the wrong-way behavior. Traveling hot spots appear only when the change of an operating condition shifts the reactor from an ignited steady state to a non-ignited one. Inlet gas flow rate variations reveal overshoots and undershoots of the reactor maximum temperature.2) Wall thermal conductivity, k w (stainless steel) 17 W m 21 K 21 Catalyst thermal conductivity, k s 9 0.87 W m 21 K 21 Catalyst particle density, q s 58 1274 kg m 23 472

show abstract

Section: Resultsmentioning

confidence: 79%

Dynamic modeling and simulations of the behavior of a fixed‐bed reactor‐exchanger used for CO₂ methanation

et al. 2017

View full text Add to dashboard Cite

show abstract

“…The properties of the FBRR and process conditions are summarized in Table as a base case for simulations. The reactor dimensions correspond to a lab‐scale experiment, though the model parameters can easily be adapted to specific application cases. Compared with previous simulations, the reactor length was ideally shortened to 0.5 m because the adiabatic reactor reaches the chemical equilibrium already in the first part of the reactor.…”

Section: Modeling and Simulationmentioning

confidence: 99%

“…With the aim to reduce the costs of the hydrogen storage by minimizing upstream storage capacities (up to 8% of the total investment costs can be saved), the unsteady‐state operation of the exothermic methanation reaction is demanded. However, the occurring phenomena and operation strategies under dynamic conditions are not exhaustively addressed in scientific literature thus far, but receive more attention in recent years . One promising approach is adiabatically operated fixed‐bed reactors, which show a good partial and excess load behavior, since the chemical equilibrium is reached within the residence time.…”

Section: Introductionmentioning

confidence: 99%

Transient Flow Rate Ramps for Methanation of Carbon Dioxide in an Adiabatic Fixed‐Bed Recycle Reactor

2019

Self Cite

View full text Add to dashboard Cite

The power‐to‐gas (PtG) process, enabling the long‐term indirect storage of electrical energy, includes the water electrolysis for hydrogen production and the subsequent hydrogenation of carbon dioxide in a methanation reactor. The dynamic operation of methanation reactors is favored to limit upstream storage capacities, but not fully understood thus far. Therefore, this contribution investigates the dynamic operation of a fixed‐bed recycle reactor during flow rate ramps with a variation of the ramp time. Load ramps of the volumetric flow rate lead to global maxima during the transition; for the methane content if the flow rate is decreased, and for the gas temperature if the flow rate is increased. Furthermore, the adaptation of the product recirculation during flow rate ramps is discussed at the end. The recycle ratio turns out to provide an additional degree of freedom for stabilizing the reactor behavior under fluctuating feed conditions.

show abstract

“…Detailed analysis of the process reveals that two or more reactor stages even with integrated cooling capabilities or subsequent purification steps seem to be inevitable to achieve high conversion and superior gas quality for the injection into the gas grid. However, Schollenberger et al proposed a concept of two honeycomb reactor stages with external oil cooling to reach 99 % CO 2 conversion, while Matthischke et al considered recycling the product of a fixed‐bed reactor to improve the heat management and transient performance.…”

Section: Introductionmentioning

confidence: 99%

CO₂ Methanation in Microstructured Reactors – Catalyst Development and Process Design

et al. 2019

View full text Add to dashboard Cite

The sulfur tolerance of mono‐ and bimetallic ruthenium catalysts for CO2 hydrogenation was investigated in microchannel reactors. H2S was selected as a model compound. It was found that a Ru/CeO2 catalyst deactivates rapidly. Ni was a much better additive to improve the catalyst stability compared to Rh and serves as a sulfur trap. The influence of the support was evaluated showing that a SiO2‐supported catalyst has a higher stability and better selectivity compared to CeO2 and TiO2. A plant concept was developed comprising two‐step methanation with a first adiabatic reactor stage followed by a plate heat‐exchanger reactor with integrated cooling which allows more than 97 % CO2 conversion. A pilot plant will be put into operation in connection with a biogas plant and an electrolyser of 50 kW power consumption.

show abstract

Unsteady-state methanation of carbon dioxide in a fixed-bed recycle reactor — Experimental results for transient flow rate ramps

Cited by 47 publications

References 16 publications

Dynamic modeling and simulations of the behavior of a fixed‐bed reactor‐exchanger used for CO₂ methanation

Dynamic modeling and simulations of the behavior of a fixed‐bed reactor‐exchanger used for CO₂ methanation

Transient Flow Rate Ramps for Methanation of Carbon Dioxide in an Adiabatic Fixed‐Bed Recycle Reactor

CO₂ Methanation in Microstructured Reactors – Catalyst Development and Process Design

Contact Info

Product

Resources

About

Unsteady-state methanation of carbon dioxide in a fixed-bed recycle reactor — Experimental results for transient flow rate ramps

Cited by 47 publications

References 16 publications

Dynamic modeling and simulations of the behavior of a fixed‐bed reactor‐exchanger used for CO2 methanation

Dynamic modeling and simulations of the behavior of a fixed‐bed reactor‐exchanger used for CO2 methanation

Transient Flow Rate Ramps for Methanation of Carbon Dioxide in an Adiabatic Fixed‐Bed Recycle Reactor

CO2 Methanation in Microstructured Reactors – Catalyst Development and Process Design

Contact Info

Product

Resources

About

Dynamic modeling and simulations of the behavior of a fixed‐bed reactor‐exchanger used for CO₂ methanation

Dynamic modeling and simulations of the behavior of a fixed‐bed reactor‐exchanger used for CO₂ methanation

CO₂ Methanation in Microstructured Reactors – Catalyst Development and Process Design