Co-current Mode Research Articles

Lipid removal by countercurrent chromatography in co-current mode in trace analysis of polyhalogenated compounds in fish

Lipid removal by countercurrent chromatography in co-current mode in trace analysis of polyhalogenated compounds in fish

On-column capillary suppressor for open tubular ion chromatography

BackgroundSuppressors with different dead volumes are required to match different suppressed ion chromatography systems. Especially for suppressed open tubular ion chromatography (SOTIC), the dead volume is a critical parameter. Both connection tubes between open tubular (OT) columns and suppressors and the dead volumes of the suppressors should be as short/small as possible to minimize peak dispersion. Suppressors with different dead volumes are required to match the various suppressed ion chromatography systems that operate at low flow rates 20–200 nL/min. ResultsWe describe three designs of on-column capillary suppressors for SOTIC: (A) on-column electrodialytic suppressor prepared by making small cracks on the cycloolefin polymer (COP) capillary at targeted locations, (B) on-column electrodialytic suppressor built on a polyether ether ketone (PEEK) capillary by removing the wall materials at target locations, (C) on-column chemical suppressor based on a single cut on a PEEK capillary at a targeted location a single cut on a PEEK capillary at a targeted location. The on-column electrodialytic suppressors work in two different modes with suppression voltage applied in co-current and counter-current direction to the eluent flow. Because of very narrow column inner diameter (i.d.), up to several hundred volts were required to suppress the hydroxide eluent, but it was found the there was a >90% loss of analytes in the suppressor accompanied with a high noise level after on-column electrodialytic suppression. Theoretical analysis reveals that high suppression voltage significantly affects the retention of specific analytes by electromigration. Further analysis indicated that the electrodialytic on-column suppressor in co-current mode would behave totally different from traditional suppressors. The on-column chemical suppression, with minimum dead volume of 0.27 nL, provides fairly well suppression of low hydroxide eluent without analyte loss in the suppressor. In design C, an efficiency of 47000 ± 1800 plates/m for Cl−, corresponding to a peak volume of 17.9 ± 0.7 nL, was obtained when separating five anion mixture (0.5 mM each) in the 25 μm i.d. AS18 latex coated PEEK OT column with an injection of 7.3 nL. Theoretical calculation revealed that a column efficiency loss of ≤3% would result in a cylindrical chemical suppression channel and thus it is taken as the acceptable dispersion contribution originating from the on-column chemical suppressor. SignificanceDifferent on-column suppressors have been designed on OT columns with i.d.s less than 30 μm. Two electrodialytic on-column suppressor designs with eluent flow parallel to the direction of electric field were proposed and tested. The eluent flow rate, analytes’ retention behavior, resistance of suppression channel, current-voltage relationship, and working principles in both co-current and counter-current were experimentally investigated and comprehensively discussed. It was found that although the on-column electrodialytic suppressions (Design A and B) are not feasible in practice, the electrodialytic on-column suppressor on co-current mode has a potential of being used as an enriching capillary column for analyte ions. Design C provides fairly well chemical suppression. Theoretical calculation indicates that the loss of column efficiency can be controlled within 3%.

Countercurrent chromatography separation of vitamin E isomers in a co-current mode.

Vitamin E represents a group of lipophilic phenolic compounds, including α-tocopherol, β-tocopherol, γ-tocopherol, and δ-tocopherol, and α-tocotrienol, β-tocotrienol, γ-tocotrienol, and δ-tocotrienol isomers. Different forms of vitamin E have been proven to exhibit varying biological activities. However, due to their structural similarities, the separation of vitamin E isomers is a challenging task. Therefore, it is crucial to establish an efficient method for isolating individual isomers. In this study, co-current countercurrent chromatography was employed to isolate vitamin E isomers from commercial capsules using a n-heptane-methanol-water (10:9.5:0.5, v/v) solvent system. The partition coefficients of the main constituents in the capsules ranged from 0.94 to 6.23, requiring over 450 min for a complete separation. To improve separation efficiency, a co-current elution mode was implemented and the flow rates of the two liquid phases as well as sample amount were examined. The results suggested that increasing the flow rate of the stationary phase and sample size could result in more effective separation, shorter separation time, and higher yield. It proved that co-current countercurrent chromatography was an effective method for the separation of vitamin E isomers.

Sample preparation of free sterols from vegetable oils by countercurrent chromatography in co-current mode

Countercurrent chromatography (CCC) is a preparative instrumental method where both the mobile and stationary phases are liquids and which are predominantly used for the isolation of natural products. In this study, we widened the scope of CCC by using it as an instrumental method for the direct enrichment of the free sterol fraction from plant oils to which they contribute with ~ 1%. For the enrichment of sterols in a narrow band, we employed the so-called co-current CCC (ccCCC) mode in which both liquid phases of the solvent system (here: n-hexane/ethanol/methanol/water (34:11:12:2, v/v/v/v)) are moved at different flow rates in the same direction. Different from previous applications of ccCCC, the lower and predominant “stationary” phase (LPs) was pumped twice as fast as the mobile upper phase (UPm). This novel reversed ccCCC mode improved the performance but also required a higher demand of LPs compared to UPm. Therefore, the exact phase composition of UPm and LPs was determined by gas chromatography and Karl Fischer titration. This step enabled the direct preparation of LPs which considerably reduced the waste of solvents. Internal standards (phenyl-substituted fatty acid alkyl esters) were synthesised and utilised to frame the free sterol fraction. This approach allowed a fractionation of free sterols based on the UV signal and compensated run-to-run variations. The reversed ccCCC method was then applied to the sample preparation of five vegetable oils. In addition to free sterols, free tocochromanols (tocopherols, vitamin E) were also eluted in the same fraction as free sterols.Graphical

Mathematical Modelling of Rotary Drum Dryers for Alfalfa Drying Process Control

Rotary drum dryers operating in co-current mode are commonly used for drying food and feed in leaf form, reducing the damage caused by the high air temperatures typical of these dryers, as well as providing advantages including reduced drying times and increased energy efficiency. However, drying control to ensure a desirable product exit moisture content is strongly based on empirical practices, which are usually jealously guarded by producers and users, grounded in simplified mathematical modelling. To overcome these uncertainties, in this work, a more complete mathematical modelling approach, based on the solution of ordinary differential equations (ODEs), is developed. The ODEs describe the drying process in the drum dryer, where the air is continuously cooled and humidified as the product dries. The mathematical model developed was experimentally verified in a drum dryer by drying alfalfa, and the maximum relative error was found to be only 2.4%. Finally, a comparison between the complete model proposed here and a simplified model was conducted, using both for drying control to keep the product exit moisture content constant (i.e., at 0.111). The results indicated that the simplified model provided values of air inlet temperatures erroneously higher, up to +8.2%, with a consequent higher energy consumption, lower dried alfalfa quality, and a greater risk of fire, given that the product exit temperature was dangerously increased.

Structural modifications of sinusoidal wavy minichannels cold plates applied in liquid cooling of lithium-ion batteries

In this article, novel configurations of wavy minichannels with both co- and counter-current operation modes are proposed for the thermal management of lithium-ion battery systems, and their performance is investigated by incorporating a 3D conjugative numerical model and an experimental test validation. The structure of each case is specified by variable wavelengths along the flow direction. Three criteria of heat transfer enhancements, temperature uniformity improvements, and flow resistance augmentations are considered to analyze the thermal and hydraulic characteristics of the nonuniform wavy minichannels. The results show that although the Nusselt number of the nonuniform cases is higher than that of the conventional ones (more than15%), they require higher friction factors (between 25.3 % and 93.6 %) to access such Nusselt numbers. At the studied range, a maximum Nu enhancement of 1.18 and a maximum f augmentation of 1.93 are recorded. It is found that the current operation mode is a key factor affecting the temperature uniformity degree. By increasing the coolant velocity from 0.106 to 0.951 m s−1 in the co-current mode, the temperature non-uniformity decreases from 14.79 to 1.10 K, while this range for the counter-current mode is from 6.73 to 0.43 K. It is also found that for a special design of the nonuniform wavy minichannels, the deviations of the temperature non-uniformity at the entire range of the coolant velocity are <0.7 K.

Comparison of Co- and counter-current modes of operation for wavy minichannel heat sinks (WMHSs)

This study aims to make a comprehensive comparison between the applications of co- and counter-current modes in the wavy minichannel heat sinks (WMHSs). In this regard, the effects of wave-amplitude (wa) and wave-length (wl) are studied at different levels. Water is used as coolant over the Reynolds number (Re) range of 100–900. Nusselt number ratio, friction factor ratio, performance index, max. base temperature difference, and pumping power are reported as quantitative results. An experimental study is also carried out to establish required data for the validation. The outputs illustrate that for both the current modes, the dependence of thermal and hydraulic characteristics on Re increases with increasing wa and decreasing wl, while the counter-current mode is more impressed by the increase of Re compared to the co-current mode. In summary, the Nusselt number ratio ranges from 1.22 to 2.96 for the co-current mode and from 1.23 to 3.17 for the counter-current mode, and the friction factor ratio ranges from 1.09 to 2.73 for the co-current mode and from 1.10 to 2.92 for the counter-current mode, and the range of performance index is from 1.18 to 2.12 for the co-current mode and from 1.19 to 2.22 for the counter-current mode. Eventually, it is found that at the same pumping powers, replacing the co-current mode with the counter-current mode can significantly boost the temperature uniformity in WMHS. The max. base temperature of about 0.84 K is recorded for WMHS with wl = 5 mm at Re = 900. It is worthy to note that the superiority of the counter-current mode increases with increasing wa and decreasing wl.

Performance analysis of hydrogen iodide decomposition membrane reactor under different sweep modes

Hydrogen iodide decomposition is the core hydrogen production step in the sulfur-iodine thermochemical cycle, which determines the hydrogen production rate and thermal efficiency of the device. The conventional decomposition reactor is limited by equilibrium conditions, so the hydrogen iodide conversion rate is low at normal reaction temperature, and membrane reactor technology can break the limit of equilibrium condition and greatly improve the conversion rate. Most of the previous hydrogen iodide membrane reactor models were built under isothermal conditions and did not consider the influence of different sweep modes. In this paper, a one-dimensional non-isothermal hydrogen iodide decomposition membrane reactor mathematical model in co-current and countercurrent sweep modes is established, and the effects of reactor parameter on hydrogen iodide conversion and hydrogen recovery rate are analyzed under the two sweep modes. The results show that the countercurrent mode can obtain higher hydrogen iodide conversion rate than the co-current mode under larger sweep flow rate, inlet pressure of reaction and permeation zone, reactor length; the maximum recovery rate of hydrogen in countercurrent mode is close to 100%. A modified membrane reactor structure combining the traditional reactor and membrane reactor is proposed, which could effectively increase the hydrogen permeation flux per unit membrane surface. In engineering application, the reasonable design of the modified membrane reactor can effectively reduce the investment cost of the membrane reactor on the premise of satisfying the hydrogen production rate.

Sugarcane juice concentration using a novel aquaporin hollow fiber forward osmosis membrane

In this work, the performance of a commercially available aquaporin HFFO membrane was studied for concentrating the sugarcane juice by adopting appropriate UF pretreatment technique. The influences of draw and feed solution flowrates, draw concentration and its direction of flow such as co-current or counter-current on water and reverse solute flux was evaluated in batch mode. The specific reverse solute flux for counter-current mode was found to be less compared to co-current mode of operation. Improved draw solution (NaCl) flowrate increased the water flux with reduced specific reverse solute flux. The FS concentration ratio was 1.65 within 12 min of batch FO operation by using 100 g L−1 draw solution. Membrane fouling was studied systematically with appropriate membrane cleaning strategy. The effect of UF clarified and raw sugarcane juice on FO membrane fouling was calculated and it was found that raw sugarcane juice led to severe membrane fouling that reduced water permeability after 60 min of operation. The membrane fouled by UF clarified juice was able to regenerate by DI water wash for 30 min, however in the case of membrane fouled by raw juice, an additional 0.1 M NaOH wash was required.

Progress of Experimental Studies in the HL-2A Tokamak

During the last several years, the HL-2A experiment has made significant progress in the following areas: (1) lower-hybrid wave (LHW) heating and current drive, (2) plasma confinement and turbulent transport, (3) magnetohydrodynamic (MHD) instabilities and energetic particle physics and (4) H-mode and edge localized mode (ELM) control. The results show that the LHW system working in the co-current mode can reach higher driving efficiency and full non-inductive lower-hybrid current drive (LHCD) has been achieved. The intrinsic poloidal torque characterized by the divergence of the residual stress is deduced from synthesis for the first time. The dynamics of spectral symmetry breaking in drift wave turbulence is in good agreement with the development of the poloidal torque to drive the edge poloidal flow. The influence of the cross-phase dynamics on turbulent stress was also investigated. The ion internal transport barrier has been observed in the NBI-heated plasma, and inside the barrier the ion thermal transport is reduced to the neoclassical level. Besides, micro-turbulence is modulated by the rotation frequency of the magnetic island, and this modulation effect is related to a critical island width. Strong E × B shear is found at the island boundary. Three kinds of axisymmetric modes, beta-induced Alfven eigenmode (BAE), toroidal Alfven eigenmode (TAE) and the ellipticity-induced Alfven eigenmode (EAE), are found to be driven unstable by nonlinear mode coupling between Alfven eigenmodes and tearing mode which is well explained by the nonlinear gyrokinetic theory. The fishbone and tearing modes were actively controlled by the electron cyclotron resonance heating (ECRH). The dynamics of the edge plasma flows and turbulence during the L–I–H transition have been dedicatedly investigated. The geodesic acoustic mode (GAM) and limit cycle oscillation (LCO) coexist for a short time and disappear in the H-mode plasma with the increasing of E × B shear flow before the I–H transition, which plays an important role in the turbulence suppression. Different techniques, such as LHW, ECRH, resonant magnetic perturbation (RMP), and impurity seeding by the laser blow-off (LBO) and supersonic molecular beam injection (SMBI), have been successfully applied to control the large ELMs. It has been found that pedestal turbulence enhancement might be responsible for the observed mitigation effect.

High Efficiency Operation Conditions in Polymer Electrolyte Fuel Cell System with Hydrogen Circulation

Water management is an essential problem to achieve PEFC’s maximum performance. Hydrogen circulation is one of the methods to humidify the cell with water produced in oxygen reduction reaction (ORR), while the overall hydrogen utilization can be 100%. Additionally, by controlling the operating conditions, such as gas flow direction, one-pass conversion, and humidifying temperature, the cell performance can be improved. Water transport distribution along the gas channel was analyzed by numerical simulation, and the competition of the proton transfer resistance, the oxygen transfer resistance, and the reaction resistance were discussed quantitatively. The results indicate that the countercurrent mode attains better performance due to higher moisture content at high humidification conditions, and the co-current mode can be chosen at low humidification condition. The one-pass conversion higher than 0.30 is required to humidify the cell sufficiently.

Biological removal of H2S gas in a semi-pilot scale biotrickling filter: Optimization of various parameters for efficient removal at high loading rates and low pH conditions

In this study, a semi-pilot scale biotrickling filter (BTF) was operated in a continuous co-current mode to remove high concentration of hydrogen sulfide (H2S) at optimum operational conditions. The early startup period of 6 days was needed, and then stable removal of H2S gas at inlet concentrations up to about 2000 ppm was successfully obtained at gas retention time (GRT) of 15 min and liquid recirculation rate (LRR) of 120 ml/min. The elimination capacities (ECs) increased linearly with increase in H2S loading rates (HLRs up to 38.5 g/m3 h), but a gradual decrease in removal efficiency was observed from a volumetric HLR of 18.1 g/m3 h. The LRR was further decreased from 120 to 30 ml/min, and the minimum liquid–gas ratio of 0.24 was found without decrease in removal efficiency. The MiSeq analysis revealed the presence of sulphur oxidizing bacteria (SOB) dominated by Acidithiobacillus caldus (>97%) at all portions of BTF.

Hydraulics characteristics of forward osmosis membrane module boundary based on FBG sensing technology: Hydraulic properties and operating condition optimization

To obtain more information on the hydraulic properties of membrane interface, the fiber Bragg grating (FBG) sensing technology was imported to investigate the effect of feed solution (FS) flow rate, draw solution (DS) flow rate and cross-flow direction on the membrane flux and membrane shear-force distribution of forward osmosis (FO) process. Results from experimental work demonstrated that a non-uniform spatial variation of the shear-force distribution exists along the membrane, and higher shear force is distributed in the middle position which resulted in higher diffusion load on the particular location of the membrane rind. Besides, increasing the inlet flow simply to a certain value didn't result in a higher shear force and lower the effect of concentration polarization (CP). Compared to co-current mode, counter-current mode showed the better hydraulic characteristics of higher shear-force, faster scouring frequency and consistent shear-force distribution, which will enhance the utilization of membrane and exhibit higher flux by increasing the inlet flow. Moreover, with the increase of FS and DS flow, the stress distribution showed more uniformed. Higher FS flow is more beneficial to FO process which will reduce ECP and improve flux in comparison to increasing DS flow which will produce adverse influence on ICP and diminish flux.

Coagulation and adsorption as pretreatments of thin-film composite-forward osmosis (TFC-FO) for ink printing wastewater treatment.

This study investigated the performance of coagulation with ferric chloride (FeCl3.6H2O) and adsorption with activated carbon used as pretreatments prior to thin-film composite-forward osmosis (TFC-FO) filtration of ink printing wastewater. Wastewater samples were collected from a printing factory located in Chao Phraya river basin where zero liquid-discharge standards are regulated. The FO filtration unit was operated in co-current mode with the cross-flow velocity of 600 mL/min using 2 M NaCl as draw solution. The FO membrane achieved 83.9-91.0% chemical oxygen demand and 91.2-99.9% color rejections. FO filtration of raw wastewater, coagulation-treated wastewater, and coagulation and adsorption-treated wastewater resulted in 56.3%, 49.0% and 46.1% of flux decline in 150 min. Scanning electron microscopy and Fourier transform infrared spectrometry results revealed that cake formation caused by colloidal particles and pore blocking from precipitation were the major fouling mechanisms. Cake-enhanced concentration polarization also promoted adsorption of color and pigments at the membrane surface. Both fouling mechanisms were successfully mitigated by adsorption following coagulation pretreatment. Overall, the combined pretreatments and FO have potential for the effective treatment and reuse of ink printing wastewater.

Modeling and Comparison a Thermally Coupled Reactor of Methane Tri – Reforming and Dehydrogenation of Cyclohexane Reactions for Syngas Production in Both Co- &amp; Counter-Current Modes

Abstract The aim of this work is a comparison of different inlets (Co- and Counter-current modes) to feed a thermally coupled reactor (TCR) in producing syngas as a valuable chemical. The novel thermally coupled reactor has been designed as a double pipe reactor where tri-reforming of methane for syngas production has been considered in the exothermic side of fixed bed plug reactor, and dehydrogenation of cyclohexane reaction occur in the endothermic side. The heat generated in the exothermic part by the walls of the tube side is transferred to the endothermic section. A steady-state homogeneous one-dimensional model predicts the performance of this reactor for simultaneous production of synthesis gas and benzene in an economical approach for both co- and counter-current modes of operation. The reversed flow of cyclohexane has been considered for the counter-current flow regime. The simulation results of co- and counter-current modes of TCR and also an optimized tri-reforming of methane (OTRM) single reactor are investigated and compared with each other. The results showed that methane conversion, hydrogen yield and ${H_2}/Co$ ratio in the exothermic side of TCR reached to 91.1 %, 1.82 and 2.1 in co-current mode and 87.8 %, 1.77 and 2.3 in counter-current mode, respectively. Additionally, the results showed that cyclohexane conversion at the endothermic side of the reactor in co- and counter-current modes achieved to 98.6 % and 99.9 %, respectively. So, the results for counter-current mode showed superior performance in hydrogen and benzene production in the endothermic side of TCR. Also, Changes in various operating parameters during the reactor have been studied.

Simulation study of an auto-thermal double-membrane reactor for the simultaneous production of hydrogen and methanol: comparison of two different hydrogen redistribution strategies along the reactor

Abstract In a continuing effort to realize the simultaneous hydrogen and methanol production via the auto-thermal methanol synthesis process, the effect of two different hydrogen redistribution strategies along a double-membrane reactor has been considered. A steady-state one-dimensional heterogeneous model was developed to compare two strategies applied in the operation of the auto-thermal methanol synthesis. It was found that the counter-current configuration exhibited the better performance compared to the reactor operated in the co-current mode from both the economic and environmental points of view. This superiority is ascribed to the establishment of a more favourable temperature profile along the reactor and also more hydrogen extraction from the reaction zone. Moreover, the influence of some operating variables was investigated on the performance of the auto-thermal double-membrane reactor in the counter-current configuration. The results suggest that utilizing this configuration for pure hydrogen and methanol production could be feasible and beneficial.

A two-dimensional mathematical model for the catalytic steam reforming of methane in both conventional fixed-bed and fixed-bed membrane reactors for the Production of hydrogen

A modelling and simulation study of catalytic steam reforming of methane is presented in this paper. A two-dimensional pseudo-heterogeneous model is developed to simulate a conventional fixed-bed reactor (FBR) as well as a fixed-bed membrane reactor (FBMR) with sweep gas added in both co-current modes for the two reactor configurations. The developed model is based on mass and energy balance equations for the catalyst phase and the gas phase in both FBR and FBMR reactors. Firstly, a study is done for describing that the temperature profiles of gaseous and solid phases reach to stable state as well as the component distributions in the two FBR and FBMR reactors. The model covers the aspect of the partial pressure of hydrogen in the membrane reactor with the permeation of hydrogen across a Pd-based membrane. The conversion of methane is significantly enhanced by the partial removal of hydrogen as from the shell side as a result of diffusion through the Pd-based membrane. Simulation results demonstrated that methane conversion of 97.21% can be achieved in FBR at operating temperature of 1250 K relative to methane conversion of 99.79% to 923 K in FBMR. The yield of hydrogen achieved to level from 2.154 in FBR at operating temperature of 1250 K while the yield of hydrogen reached to level from 3.731 with a thickness from 1.7 μm in FBMR reactor.

Radial multiphase thermal conductivity and wall heat transfer coefficient of ceramic sponges in co-current multiphase flow – Experimental results and correlation

In this publication, experimental results for the radial multiphase thermal conductivity and the wall heat transfer coefficient of different ceramic sponges as column internals for trickle beds are presented. The experiments were performed in co-current mode with the fluids water and air. The material, porosity and cell density of the sponges were varied. A strong influence of the superficial liquid velocity and of the cell density on the radial multiphase thermal conductivity is found. Dimensionless correlations of the experimental data are given.

Modelling and simulation in conventional fixed-bed and fixed-bed membrane reactors for the steam reforming of methane

This paper presents a dynamics mathematical model to simulate the steam reforming of methane that take place in conventional fixed bed reactor (FBR) as well in fixed bed membrane reactor (FBMR) with steam added both with co-current mode. The model covers all aspects of main chemical kinetics, heat and mass phenomena in the membrane reactor with hydrogen permeation in radial direction across a Pd-based membrane. Firstly, a dynamics study was made for describing that temperatures of gaseous and solid phases reach to steady-state as well as molar flow rates. The effect several parameters including the axial position (z) divided by the reactor length Lz, reaction temperature and hydrogen partial pressure (PH2=Ppz) in permeation side were investigated. The conversion of methane is significantly enhanced by the partial removal of hydrogen from the reaction zone as a result of diffusion through the Pd-based membrane. Simulation results showed that a conversion from 99.85% could be achieved in a FBMR at reaction temperature of 600 °C relative to a conversion from 88.87% to 950 °C in a FBR. Besides, results showed that the yield of H2 reached to level from 1.548 (dynamics-state) and 1.626 (steady-state) in a FBMR at reaction temperature of 550 °C while the yield of H2 achieved to level from 1.261 (dynamics-state) and 1.445 (steady-state) in a FBR at reaction temperature of 725 °C.

Modelling, simulation and design of an integrated radiant syngas cooler and steam methane reformer for use with coal gasification

In this work, a novel process intensification design is proposed to integrate the Radiant Syngas Cooler (RSC) utilised to cool the coal-derived synthesis gas in entrained-bed gasifiers and a steam methane reformer (SMR). The feasibility of the proposed integrated system is analyzed by developing a rigorous, dynamic, multi-dimensional model and establishing design heuristics for the integrated system. Two different flow configurations are explored; co-current and counter-current. The simulation results show that the proposed concept is feasible that allows for methane conversions as high as 80% in co-current mode and 88% in counter-current mode. The results also demonstrate that the counter-current design, though with higher conversion and cooling duty provided when compared to co-current designs, is limited by the tube wall material limitations. Our analysis shows that the total avoided CO2 emissions is 13.3tonnes/h by using the proposed integrated configuration in place of an external reformer for the natural gas feed rates considered in this study. In addition, a sensitivity analysis is performed on key model assumptions and the resulting effect on the performance is assessed. The sensitivity results have helped identify key factors to consider prior to pilot-scale implementation and further improvement for agile designs; a one third reduction in tube length reduced pressure drop by as much as 50% but reduces methane conversion by 15% points, neglecting slag deposition on tubes over-predicts performance only by 3%, and a 10% change in gas emissivity calculations affects model prediction of performance by less than 1%.