Reactor Diameter Research Articles

Photocatalytic degradation of ethylene in tubular microreactor coated with thin-film of TiO2: Mathematical modeling with experimental validation and geometry analysis using computational fluid dynamics simulations

The study aimed to establish a comprehensive understanding of the photocatalytic process and optimize the reactor design for efficient ethylene regulation to improve the shelf-life of fruits and vegetables. For this, it was performed 2D computational fluid dynamics modeling at two different reactor geometry (conventional cylindric reactor and annular cylindric reactor) using the conservation equations combined with Langmuir-Hinshelwood mechanism. A continuous single-phase multicomponent fluid flow with the reactor surface supported with a thin-film catalyst under UV-A light irradiation was simulated for initial ethylene concentration at 0.479–4.234 × 10−3 molC2H4 m−3 and inlet axial velocity at 0.0085–0.1019 m s−1. In the 2D CFD results, it was observed that the difference in ethylene concentration between the microreactor bulk and surface is only significant for high initial concentrations and axial velocities. Furthermore, it was found that the parabolic conversion profile remains unchanged for lengths greater than 10% of the reactor length across all geometries studied. The variation in reactor diameters resulted in a substantial reduction in ethylene conversion; however, the incorporation of an annular cylinder coated with a catalyst led to an enhancement in conversion rates, with improvements of approximately 28%, 17%, and 6% observed for diameters of 5 mm, 10 mm, and 20 mm, respectively. This reduction in improvement as diameter increase can be attributed to the laminar flow dynamics that impede the diffusion of ethylene molecules from the bulk to the catalytic surface. Consequently, the simulated data highlight the potential of employing a catalyst-doped annular cylinder as a promising strategy to increase ethylene conversion and extend the shelf life of fruits. However, it should be noted that the addition of an annular cylinder, while enhancing conversion, also introduces operational complexities and cost implications due to the significant increase in pressure drop associated with lower diameters.

Experimental characterization and mixing modeling of a horizontally rotating disc reactor

Mixing is important in many chemical and biochemical processes to ensure uniform conditions throughout the process volume. A complex interaction arises for heterogeneous systems sensitive to the stress induced by mechanical mixing devices. This work introduces the Rotating Disc Reactor consisting of a horizontally rotating cylinder of a small width and partial filling, potentially allowing low-shear mixing. A colorimetric approach was implemented to study the mixing behavior. An increase in rotational speed resulted in a maximum reduction in mixing time by a factor of 7.5, while a higher filling level increased the mixing time by 20%. Also, doubling the reactor diameter doubled the mixing time at the same circumferential speed, and quadrupling the reactor width prolonged the mixing process similarly. Finally, a model is proposed to describe the dependencies of the dimensionless mixing number with a set of dimensionless groups.

Prediction of three-phase product yield of biomass pyrolysis using artificial intelligence-based models

Further efforts are still needed to refine and optimise complex thermochemical pyrolysis processes crucial in waste management and clean energy production. In this work, a comparative artificial intelligence (AI) based modelling study is conducted using four supervised machine learning models, including artificial neural network (ANN), random forest (RF), support vector regression (SVR), and extreme gradient boosting (XGB) to predict the three-phase product yields of pyrolysis. The models were trained using a database of previous experiments focused on continuous pyrolysis in fluidised bed reactors, with biomass feedstock characteristics and pyrolysis conditions as input features. A reactor dimension parameter through H/D (the ratio of the reactor height, H and the reactor diameter, D), for the first time, is also included as an input feature. The models are optimised through feature reduction and 5-fold cross-validation hyperparameter tuning. They show that reducing the organic composition of biomass to include only chemical composition results in the best feature-reduced model. After the comparison of performance scores and total feature importance, the general ranking for AI model accuracy for this study is XGB>RF>ANN>SVR. The H/D ratio also has the highest feature importance scores of 21.71% and 29.52% in predicting the oil and gas yield of the feature-reduced XGB model, confirming the importance of this added parameter. Preliminary contour plot analysis of the database shows that for the considered reactors, optimum oil yields are obtained at H/D ratio< 5, while the optimum gas yields are expected at H/D ratioc closer to 10 for fluidised bed reactors as another indicator of factor importance.

Process Simulation of Power-to-X Systems—Modeling and Simulation of Biological Methanation

Through utilization of state-of-the-art power-to-x technology, biological methanation is a novel method to capture the intermittent electricity generated by renewable energy sources. In this process, biomass grows in a liquid solution by consuming H2 and CO2 and produces CH4. This study aims to improve the accuracy and comprehensibility of an initial bio-methanation model by reviewing and comparing existing technologies and methods, correcting miswritten equations, adding complementary equations, and introducing a new initialization approach. In addition, a mean value approach was used for calculating the axial mixing coefficients. Gas–liquid mass transfer in the reactor, along with other aspects, is considered the most challenging aspect of the biological methanation process due to hydrogen’s low solubility. This highlights the need for a modeling approach to improve understanding and optimize the design of the process. The improved MATLAB code was used to test different variations of parameters in the reactor and observe their effects on the system’s performance. The model was validated using experimental cases, and the results indicate that it is more accurate than Inkeri’s for certain parameter variations. Moreover, it demonstrates better accuracy in depicting the pressure effect. The sensitivity analysis revealed that liquid recycle constant λ had little effect on methane concentration, while impeller diameter dim and reactor diameter dre had significant impacts. Axial mixing constants b1 and b2 and biological kinetics constants kD, µmax, and mX had relatively small effects. Overall, the study presents a more comprehensive bio-methanation model that could be used to improve the performance of industrial reactors.

Design and Development of a Novel Hybrid Gasifier for High Ash Content Coal as feed stock

India has large proven reserve of coal but most of the coal has large quantity of ash. Utilization of this high ash content coal is again a verychallenging task. Presently, gasification of high ash coals has not yet been in application due to the difficulties arising from the ash handlingprocesses. In this work an attempt was made to design a partially fluidized bed reactor that can handle 30 kg/hr coal as a feedstock. By usingan appropriate design procedure a complete design of a hybrid gasifier was studied deeply. The major aim of present research is todetermine the air flow rate for proper gasification, reactor diameter and reactor height, feed particle diameter, nozzle orientation and numbernozzles, reduction zone diameter and height. Experiments were carried out with feeding rate of 9.8 kg/hr with high ash content coal having39.83% ash. Satisfactory results have been found during experiments. The average producer gas generation during trial run was found to be29.8 Nm3/hr while average calorific value of producer gas was about 4500 kJ/Nm3. The work described here favours us understand the realgasification process for high ash content coal and thus facilitates the industrial application of gasification technology.

Ammonia thermal decomposition on quartz and stainless steel walls

Ammonia has been proposed as a promising solution for hydrogen carriers as well as clean fuels. However, the reaction kinetics is still not robust in many engineering applications, where the deviation is mainly caused by the surface reactions of ammonia on the wall. To examine the ammonia surface reaction on engineering materials, in the present study, the thermal decomposition of ammonia is systematically investigated in uniformly heated quartz/SUS304 tubular flow reactors with the prescribed heating length. A decrease in the inner diameter of the quartz tubular reactor leads to an increase in the ammonia thermal decomposition rate, showing that the thermal decomposition reaction occurs even on quartz surfaces, which is usually believed to be inert. The thermal decomposition on the SUS304 reactor surface starts from as low as 700 K, indicating it is much more reactive than the quartz surface. One-step surface reaction models of ammonia for quartz/SUS304 surfaces are proposed, with which the reaction rates are estimated based on the experimental data. The inner surface of the SUS304 tubular reactor after the thermal decomposition experiments is examined by X-ray photoelectron spectroscopy. The formation of iron nitride on SUS304, which in turn facilitates ammonia thermal decomposition, reveals the positive feedback between ammonia decomposition and nitriding. Moreover, the present one-step surface reaction on stainless steel has been validated by measuring ammonia distributions in the preheat zone of NH3/O2/N2 premixed flame impinging on a stainless steel plate through a two-photon absorption laser-induced fluorescence (TALIF) technique.

Dimensioning Air Reactor and Fuel Reactor of a Pressurized Chemical Looping Combustor to Be Coupled to a Gas Turbine: Part 1, the Air Reactor

This paper provides a simple methodology for the design of the air reactor of a chemical looping combustor to optimize its characteristics when it is employed connected to a turbo expander to produce power. The design process, given a certain objective (e.g., electric power) defines the reactor specifics, namely height and diameter, taking into account the following aspects: solids inventory of the air reactor; gas velocity; air reactor transport disengaging height (TDH); solids concentration profile along the reactor height, dense bed height; freeboard height; pressure drop depending on air reactor injectors design and configuration. The total air reactor height was about 9.5 m, while the diameter was about 1.8 m. The total inventory was about 10,880 kg; while the circulation rate in the air reactor was about 110 kg/s. The operating pressure and temperature were, respectively, 12 bar and 1200 °C. The average velocity of the gases inside the reactor was about 4 m/s. The fluidization regime resulted to be comprised between turbulent and fast fluidization. Further work must be directed into the estimate of the pressure drop of the reactor, which will affect the plant efficiency in a considerable way.

Study of Flow Patterns in a Moving Bed Reactor for Chemical Looping Combustion Based on Machine Learning Methods

Abstract A tower-type moving bed can be used as the air reactor in a chemical looping combustion system because of its low-pressure drop and smooth operation. In our previous simulation, a quasi-two-dimensional numerical model was established using discrete element method (DEM) approach to investigate the velocity and solid residence time distributions in the moving bed. In this work, the flow patterns under different operating and structural parameters are studied and optimized via machine learning methods. The random Forest regression model is applied to evaluate the importance of each variable to the solid flow pattern, while the feed forward neural network is applied to buildup a high-accuracy model to predict the solid axial velocity in the moving bed without the requirement to understand the physical mechanisms. Results show that the solid mass flux has the least impact on the mass flow index, while the axial position has the dominant influence and what comes next is the wedge angle, reactor angle, and ratio of down-comer diameter to reactor diameter. Further, based on the established feed forward neural network model, relation between the effective transition position and structural parameters of the moving bed is built, which provides valuable guidance for optimization of the reactor configuration.

Thermal management and optimization of the reactor geometry for adsorbed natural gas storage systems subjected to free convection and radiative environment

The present investigation explores the effects of the reactor geometry (i.e., the aspect ratio of cylindrical and annular reactors with and without fins, fin spacing, the aspect ratio of fins for finned reactors, and outer to inner diameter ratio for annular unfinned reactors) on the heat and mass transfer characteristics of the adsorbed natural gas storage system employing passive cooling techniques. The authors try to capture how the geometric modification changes the surrounding buoyancy-driven flow physics and improves the proposed novel reactor's storage performance. The study also considers surface radiation, which significantly improves the heat transfer rate, especially for the reactor with lower internal thermal resistance. An attempt is made to reduce the internal thermal resistance of the adsorbent bed by adding 10% graphite by mass and suitably modeling the bed's thermal conductivity and thermal capacity. The result shows that, in terms of adsorbed amount and heat transfer rate, the reactors with an aspect ratio (AR) of 7.8 outperform the other aspect ratios. The simultaneous effects of reactor aspect ratio and fins spacing on the heat transfer and adsorption rates are expounded, and the optimum fin spacing as a function of reactor aspect ratio and diameter ratio (i.e., fin diameter to reactor diameter) is obtained. The best annular reactor outperforms the cylindrical reactor with and without fin in terms of volumetric and gravimetric storage capacity. The annular finned reactor achieves a maximum 33% improvement in storage capacity compared to the adiabatic case and isothermal efficiency of 90%.

Three-dimensional cellulose-based hierarchical porous continuous flow catalytic reactor for water purification

Inspired by the saccharum officinarum cellulose frameworks, a naturally hierarchical structured based continuous flow catalytic reactor (ZIF-67@SCF CFR) was constructured, which was employed to reduce 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in an effective and persistent way. The hierarchical structured based saccharum officinarum cellulose frameworks have numerous aligned and open microchannels, abundant porosity, which afford nanometer grade perforation panel and the regular fibrovascular bundles and high-throughput transport and the abundance of highly active sites for growing ZIF-67 nanoparticles. The resulting built hierarchical saccharum officinarum cellulose frameworks continuous flow reactor is as demonstrated by evaluating their activity in a model of catalytic reaction. The resultant ZIF-67@SCF CFR (5 cm length, 15 mm diameter) exhibits superior 4-NP catalytic efficiency up to 100% after 40 min, and the long-term stability of ZIF-67@SCF CFR was verified by continuously using 360 min, maintaining degradation efficiency of 40% after 240 min. Herein, the built ZIF-67@SCF CFR has a certain persistence performance in degrading pollutants as a continuous flow catalytic reactor. And the ZIF-67@SCF CFR has recyclability after freeze-drying and self-assembly processing. Moreover, the results show that the catalytic efficiency of ZIF-67@SCF CFR increases with the growth of diameter and length of reactor. In short, naturally hierarchical structured based biomass material continuous flow reactor like ZIF-67@SCF CFR with the features of natural, renewable, and degradable, has a special consistent of complicated multi-level porous structures, nano-level perforation plates, and regular agreement fibrovascular bundles, which could be employed as a promising candidate to reduce the water pollutants. In this work, we reported a naturally hierarchical structured based saccharum officinarum cellulose frameworks continuous flow reactor (ZIF-67@SCF CFR), becomes an effective persistent usability on water pollution treatment. The resultant ZIF-67@SCF CFR (5 cm length, 15 mm diameter) exhibits superior 4-NP catalytic efficiency up to 100% after 40 min, and the long-term stability of ZIF-67@SCF CFR was verified by continuously. Moreover, we proved that the catalytic efficiency of ZIF67@SCF CFR increase with the growth of diameter and length of reactor. We believe the simple and facile material and method has great potential for reducing the water pollutants

Gas-jet HFCVD synthesis of diamonds from mixtures of hydrogen with ethylene and methane

The gas-jet deposition method (a modification of the Hot Filament Chemical Vapor Deposition method (HFCVD)) was used to deposit some diamond structures on a molybdenum substrate from a hydrogen-ethylene mixture activated on hot tungsten. The experiments were performed for two lengths of activation reactors at different ethylene flow rates. For comparison, some diamond structures were synthesized from a hydrogen-methane mixture under similar conditions. The resulting structures were studied with the scanning electron microscopy and Raman spectroscopy methods. The reacting mixture flow through the heated catalytic channel was simulated by solving the Navier-Stokes equations accounting for homogeneous and heterogeneous chemical reactions. The reactor (hot tungsten tube) length and diameter effects as well as carbonaceous admixture supply effects were analyzed. The main diamond precursor's formation pathways were analyzed and the reaction chains' complexity was demonstrated. The simulation results are in good agreement with the experimental data. The numerical experiments made it possible to reveal the growth process key driving parameters.

Physical phenomena of a cold plasma jet model at atmospheric pressure

In this work, a two dimensional (2D) axisymmetric fluid model for an atmospheric pressure plasma jet (APP jet) driven by a 8 kV voltage pulse with a repetition frequency of 50 kHz has been investigated. The aim is to identify the physical phenomena taking place in a cold plasma jet at atmospheric pressure assuming an argon pathway in the air. This model is a platform for future works where the simulated reactor will be used for different plasma jet applications. It is built through the coupling between plasma discharge and flow physics using COMSOL@ Multi-physics software. The simulation results showed that the high value of the electric field in the head of the plasma jet channel attracts free electrons and ensures its propagation to around 1cm of length with an electron density of 1020 m−3. We have also shown that electrons in the neutral zone of the plasma (channel) have a lower temperature compared to electrons in electrostatic sheaths (channel boundaries), although, their temperature remains remarkably higher than neutrals and ions ones. The total electric current calculated by the proposed model takes a maximum value of 7.71 mA. This value increases with increasing tube reactor diameter which changes the reactor equivalent capacity.

Continuous Synthesis of 5-Oxohexanenitrile in a Microreactor: From Kinetic Study to Reactor Modeling

Synthesis experiments of 5-oxohexanenitrile through the addition of acetone to acrylonitrile at the temperature range of 200–230 °C were carried out in a microreactor. Based on the experimental data, a semiempirical kinetic model was established and validated. According to the developed kinetic model, the effects of the molar ratio of acetone to acrylonitrile, the concentration of N-propylamine, and the initial water content were further investigated. By coupling the semiempirical kinetics with the plug flow reactor model, studies on the effect of the reactor diameter, the residence time, and the reaction temperature were performed to shed some light on the design and optimization of the industrial tubular reactors for the production of 5-oxohexanenitrile.

Increased Electromagnetic Wave Absorption through Controlled Sonication Processing on BaFe11.2Mg0.4Al0.4O19 Nanoparticles

Electromagnetic waves show rapid development in electronics, telecommunications, and the military. One of the efforts to overcome the effects of electromagnetic interference is by developing microwave-absorbing materials. Barium hexaferrite is the best candidate for development as an absorber material. Microwave absorption in barium hexaferrite can be increased through Mg-Al doping and reducing the particle size. This study aimed to analyze sonication parameters to reduce the particle size by combining destruction methods using mechanical alloying followed by high-power ultrasonic irradiation. Barium hexaferrite was synthesized through mechanical alloying by mixing stoichiometric BaCO3, Fe2O3, Al2O3, and MgO (Sigma-Aldrich p.a 99%) (Mg-Al 0.4%wt). The samples continued the sintering process at 1200 °C for 2 h to grow crystal embryos. The optimal parameters for ultrasonic destruction were using a transducer:reactor diameter ratio of 1:10, a particle density of 5 g/250 mL, and adding a non-ionic surfactant of 0.01% at an amplitude of 55% and a sonication time of 8 h. These methods resulted in the saturation magnetization of 18.50 emu/g and a coercivity of 0.08 Tesla. The reduction in the particle size of BHF doped with Mg-Al was successfully up to 21 nm, resulting in a reflection loss of up to −40.8697 dB at 11.896 GHz (x-band, 8–12 GHz). The BHF nanoparticles doped with Mg-Al effectively absorbed up to 99.99% electromagnetic waves.

A 6-kW thermally self-sustained two-stage CO2 methanation reactor: design and experimental evaluation of steady-state performance under full-load conditions

This study designed and evaluated a 6-kW, two-stage CO2 methanation reactor, with the aim of effectively recovering the heat generated by the reaction and condensation of the by-product H2O, securing a high CO2 conversion (≥99%) under low pressure without any external thermal input for catalyst temperature control, i.e., thermally self-sustained. The H2 feed was split, with the majority being fed into the first reactor and the remainder into a second reactor. The heat-carrier flow was also split between the stages and, thereby, the second reactor was cooled by supplying only a fraction of the heat-carrier that had been heated in the first reactor. Reactor inner diameters of 16 and 25 mm, as well as parallel and counter flow heat exchange configurations were compared in the second reactor, using a 1-kW test rig. The results showed that the use of a 16-mm reactor diameter and a parallel flow configuration in the second reactor realize a higher total heat recovery with the 99% CO2 conversion. The steady-state performance of the designed 6-kW two-stage reactor was evaluated at 200 kPa (G) under full load. The reactor consequently recovered more than 70% of the total generated heat at 99% CO2 conversion, increasing the heat-carrier temperature from room temperature (inlet heat-carrier temperature) to 137 °C (outlet heat-carrier temperature).

Heat and mass transfer characteristics of charging in a metal hydride-phase change material reactor with nano oxide additives: The large scale-approach

Integrating metal hydride (MH) for hydrogen storage with phase change materials (PCMs) received increasing attention today to ensure effective thermal management in MH-storage reactors and reduce the operating cost of the process. This study revealed the first coupling approach (at large scale) of hydrogen storage in LaNi5 alloys with heat recovery by using a PCM loaded with nanoparticles (i.e. the MH-nano-PCM system) in a cylindrical MH-tank reactor (diameter: 1 m) equipped with four tubes of nano-PCM. Mass and heat transfer phenomena were computationally analyzed in the diverse regions of the reactor. The temporal temperature profiles (average and contours), the MH-hydrogenation efficiency, the velocity contours and PCM-liquid fraction were established in the presence (at 5% v/v) and absence of four types of nano-oxides (Al2O3, MgO, SnO2 and SiO2). Significant results were obtained. The nano-PCM system efficiently recuperates the heat lost from the exothermal absorption reaction; however, a slight reduction in the latent energy storage unit's performance is obtained compared to pure paraffin, probably due to the thermo-transfer resistant created by the nano-particles agglomeration during the melting cycle. The PCM-tube position plays a crucial role in the PCM melting rate, where the tube located above the H2-charging pipe melts more quickly than the other tubes.

Experimental study and kinetic modeling of continuous flow conversion of fructose to 5-(chloromethyl)furfural using micro- and millistructured coiled flow inverter

5-(chloromethyl)furfural (CMF) can be derived from renewable feedstocks and is considered as potentially biorenewable platform chemical. Experimental investigations and kinetic modeling of the conversion of d-fructose with aqueous HCl to CMF by a reactive extraction was undertaken with a continuous flow setup. Experiments were performed under variation of extraction solvents, reaction temperatures, fructose concentrations, and reactor diameters for various residence times so that time evolution of species concentration allowed for detailed kinetic analysis. Anisole, a solvent ranked as “recommended” by the CHEM21 selection guide was found to be an environmentally more benign alternative to the typically employed chlorinated extraction solvents. A maximum CMF yield of 79 % was obtained at 90 °C within a residence time of 265 s. Kinetic modeling under non-limiting mass transfer conditions showed general consistency of experimental data with the view that the reactions take place solely in the aqueous phase and that CMF is formed consecutively via 5-(hydroxymethyl)furfural (HMF) from fructose. Under these conditions no side-product formation from CMF and HMF was discernible. Activation energies for conversion of fructose to HMF of 94 ± 8 kJ/mol, of HMF to CMF of 85 ± 6 kJ/mol, and for conversion of CMF to HMF of 74 ± 25 kJ/mol were observed. To the best of our knowledge this study provides the first detailed kinetic investigation of biphasic CMF synthesis under variation of several experimental parameters in continuous flow.

Assessing performance of methane tri-reforming reactor using a parametric study on the fundamental process variables

This study represents a numerical investigation of the methane tri-reforming with full computational fluid dynamics and reaction mechanisms in an adiabatic fixed-bed reactor. A 2-D axisymmetric model over nickel-based catalysts is stablished to analyze the influence of relevant parameters. The attained results revealed that the feed composition, feed flow rate, inlet temperature, operating pressure and reactor geometry have important effects on the efficiency of the reactor. The observed temperature profile proves that the temperature peak increase with the inlet temperature. Moreover, the H2/CO ratio increases with decrement of O2/CH4 and CO2/CH4 and increment of H2O/CH4. As the feed flow rate rises, the CH4 conversion, CO2 conversion and the syngas ratio reduce. One of the most attractive results is the correlation between the pressure and the reactor performance. When the pressure falls, whereas less O2 is consumed, the CH4 and CO2 conversion rise due to the increase of the initial reaction rates. Finally, it is proved that the variations of the reactor diameter have a greater impact on the reactor performance compering with the reactor length.

Development of small-scale experimental method for vent sizing and observation of runaway reaction

Safety valves for reaction runaway are important to install in order to prevent ruptures of equipment. However, safety valves are not easy to accurately design for a pressure increase due to a runaway reaction. A vent-sizing method for two-phase flow was developed by the Design Institute for Emergency Relief Systems (DIERS) under the auspices of AIChE in 1987, and the API standard 520 and ISO 4126–10 was published in 2010s’. These standards defined conservative assumptions. Therefore, sometimes non-realistic results, such as bigger safety valves than the reactor diameter, are obtained. For the investigation of a more accurate design, detailed analysis of safety valves with Aspen were studied in my previous study. Simulation technology gives a great deal of useful knowledge. However, it is necessary to verify the simulation results. Therefore, a 40 mL-scale small test instrument with a safety valve was developed, and runaway experiments were carried out in this study. The results of case studies of simulation corresponded to experimental results. Furthermore, this experimental method can estimate the vent size directly without complicated analysis, such as the ISO method or a detailed simulation. In addition, the combination of case studies of the experiment and simulation provides various additional knowledge, such as moderating measure for runway reaction and preventing measure for occurrence of two-phase flow in the reactor. This study contributes to the design of resilient processes for process upsets and will lead to sustainable and economical design.

Methanation Pilot Plant with a Slurry Bubble Column Reactor: Setup and First Experimental Results

As a part of various research projects, a methanation pilot plant with a slurry bubble column reactor (SBCR) was commissioned and operated. The plant has a nominal load of a 100 kW methane output (lower calorific value) with a reactor diameter of 260 mm and a reactor length of 2500 mm. First experimental data on the steady-state and dynamic operation of catalytic CO2 methanation are presented. Steady-state results from laboratory-scale studies (<1 kW methane output) published previously were confirmed qualitatively at the pilot plant eliminating wall effects unavoidable in small-scale reactors. As predicted, high H2/CO2 ratios increase CO2 conversion, but excess H2 apparently promotes decomposition of the liquid phase (dibenzyltoluene) used in the bubble column reactor. Additionally, due to the increased reactor dimensions compared to laboratory equipment, it was now possible to observe a thermal response of the SBCR under conditions of rapid gas load changes characteristic of envisaged power-to-gas applications with volatile renewable electricity. As the predicted robustness of the SBCR-concept toward a dynamic operation with fast load changes was demonstrated successfully, it offers an attractive alternative to the established fixed-bed methanation technologies with their inherent limitations on dynamic operability.