Sweep Gas Flow Rate Research Articles

Application of Zn-ferrite towards thermochemical utilization of carbon dioxide: A thermodynamic investigation

This study reports a thermodynamic analysis of ZnFe2O4 based CO2 splitting cycle. The model developed is evaluated by using HSC Chemistry software. Effects of the influence of the ratio of the molar flow rate of inert sweep gas to the molar flow rate of ZnFe2O4, thermal reduction temperature, and gas-to-gas heat recovery effectiveness on thermal energy required to drive the cycle and the solar-to-fuel energy conversion efficiency are investigated at reduction nonstoichiometry of 0.1. The decrease in the reduction temperature is significant when the ratio of the molar flow rate of inert sweep gas to the molar flow rate of ZnFe2O4 increases from 10 to 30. At a steady gas-to-gas heat recovery effectiveness equal to 0.7, a rise in the ratio of the molar flow rate of inert sweep gas to the molar flow rate of ZnFe2O4 from 10 to 90 is responsible for an increase in the thermal energy required to drive the cycle above 184.9 kW by a factor of 1.45 and decrease in the solar-to-fuel energy conversion efficiency by 4%. At gas-to-gas heat recovery effectiveness equal to 0, the difference between the thermal energy required to drive the cycle at the ratio of the molar flow rate of inert sweep gas to the molar flow rate of ZnFe2O4 equal to 10 and 100 is 346.5 kW. However, as the gas-to-gas heat recovery effectiveness increases to 0.9, this difference decreases to 11.8 kW. Because of this, the reduction in the solar-to-fuel energy conversion efficiency also drops to 0.6%. Therefore, a maximum possible solar-to-fuel energy conversion efficiency equal to 16.8% can be achieved.

Development and Proof of Concept of a Compact Metallic Reactor for MIEC Ceramic Membranes.

The integration of mixed ionic–electronic conducting separation membranes in catalytic membrane reactors can yield more environmentally safe and economically efficient processes. Concentration polarization effects are observed in these types of membranes when O2 permeating fluxes are significantly high. These undesired effects can be overcome by the development of new membrane reactors where mass transport and heat transfer are enhanced by adopting state-of-the-art microfabrication. In addition, careful control over the fluid dynamics regime by employing compact metallic reactors equipped with microchannels could allow the rapid extraction of the products, minimizing undesired secondary reactions. Moreover, a high membrane surface area to catalyst volume ratio can be achieved. In this work, a compact metallic reactor was developed for the integration of mixed ionic–electronic conducting ceramic membranes. An asymmetric all-La0.6Sr0.4Co0.2Fe0.8O3–δ membrane was sealed to the metallic reactor by the reactive air brazing technique. O2 permeation was evaluated as a proof of concept, and the influence of different parameters, such as temperature, sweep gas flow rates and oxygen partial pressure in the feed gas, were evaluated.

Dehydration of bio-alcohols in an enhanced membrane-assisted reactor: A rigorous sensitivity analysis and multi-objective optimization

Green and efficient routes for a sustainable and renewable strategy in chemicals and energy delivery are highly demanded in the current status. Developing production routes from bio-alcohols is of immense interest. To achieve such a goal, an enhanced membrane-assisted dehydration reactor for the conversion of bio-alcohols (mainly made up of methanol and ethanol) is suggested. The system can eliminate the innate and produced water through the dehydration reaction, representing an intensified process that favors a conversion enhancement without needing a water purification unit. This study includes a rigorous feasibility study utilizing a validated mathematical model. The impacts of input variables such as feed flowrate, feed temperature, feed composition, and feed pressure, as well as the sweep gas flowrate and temperature, are examined. The sensitivity analysis is conducted in terms of feed conversion, temperature profiles, pressure drop, and desired product distributions. Then, an optimization strategy was developed to obtain the optimum operating conditions of each system leading to maximized conversion and product yields. According to the achievements of this study, the enhanced membrane-assisted dehydration reactor offers a great capacity for converting bio-alcohols and producing considerable quantities of DME from bio-methanol as well as DEE, ethylene, and butylene from bio-ethanol.

Comparison of Circular and Parallel-Plated Membrane Lungs for Extracorporeal Carbon Dioxide Elimination.

Extracorporeal carbon dioxide removal (ECCO2R) is an important technique to treat critical lung diseases such as exacerbated chronic obstructive pulmonary disease (COPD) and mild or moderate acute respiratory distress syndrome (ARDS). This study applies our previously presented ECCO2R mock circuit to compare the CO2 removal capacity of circular versus parallel-plated membrane lungs at different sweep gas flow rates (0.5, 2, 4, 6 L/min) and blood flow rates (0.3 L/min, 0.9 L/min). For both designs, two low-flow polypropylene membrane lungs (Medos Hilte 1000, Quadrox-i Neonatal) and two mid-flow polymethylpentene membrane lungs (Novalung Minilung, Quadrox-iD Pediatric) were compared. While the parallel-plated Quadrox-iD Pediatric achieved the overall highest CO2 removal rates under medium and high sweep gas flow rates, the two circular membrane lungs performed relatively better at the lowest gas flow rate of 0.5 L/min. The low-flow Hilite 1000, although overall better than the Quadrox i-Neonatal, had the most significant advantage at a gas flow of 0.5 L/min. Moreover, the circular Minilung, despite being significantly less efficient than the Quadrox-iD Pediatric at medium and high sweep gas flow rates, did not show a significantly worse CO2 removal rate at a gas flow of 0.5 L/min but rather a slight advantage. We suggest that circular membrane lungs have an advantage at low sweep gas flow rates due to reduced shunting as a result of their fiber orientation. Efficiency for such low gas flow scenarios might be relevant for possible future portable ECCO2R devices.

Pyrolysis of walnut shell residues in a fixed bed reactor: Effects of process parameters, chemical and functional properties of bio-oil

In the present work the products and characteristics of bio-yields obtained from pyrolysis of different types of walnut shells (WS) by using a fixed bed pyrolyzer. The different walnut shells considered are paper (PSW), thin (TSW), medium (MSW) and hard (HSW) shelled walnut. The biomass samples were pyrolyzed at various temperatures, particle sizes, heating and sweep gas flow rates. The results revealed that the maximum bio-oil 44.7, biochar 37.6 and gas 40.4 wt% yields have been obtained for HSW, MSW and HSW at a pyrolysis temperature of 550, 375 and 750 °C respectively at heating rate 0.33 K/sec, particle size 0.5–1.5 mm with swept gas flow rate 1.6 × 10−6 m3/s. The higher heating value (HHV) of bio-oil obtained from different walnut shells are ranged from 26 to 27.3 MJ/kg. Comprehensive physiochemical characteristics such as density, viscosity, flash point, pour point and water content of bio-oils have been obtained. Chemical composition analysis of bio-oils revealed that the pyrolytic bio-oil composition is predominated by oxygenated compounds such as carbonyl, methoxy, phenols and carboxyl groups determined by GC-MS, FTIR, 1H NMR and 13C NMR. The pyrolysis gas mainly contained CH4 CO, H2, CO2, and light hydrocarbons. Based on these results and structural analysis of the bio-oil, it can be concluded that the bio-oil obtained from WS may be used as a feedstock for furnaces, as a fuel, as a lubricant after modifications and value-added products via pyrolysis.

Single- and dual-phase capillary membranes prepared through plastic extrusion method for oxygen permeation

Two capillary membranes, single-phase Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) and dual-phase 75 wt% Ce0.85Sm0.15O1.925 - 25 wt% Sm0.6Sr0.4Cr0.3Fe0.7O3-δ (SDC-SSCF), with dense cross section, were successfully prepared through the plastic extrusion method. The dual-phase capillary membrane shows higher strength compared to the BSCF counterpart, while the two capillary membranes exhibit much higher fracture strength than those of hollow fiber membranes. The oxygen permeation fluxes of both membranes increase with the increase of temperature and flow rate of sweep gas at the ambient pressure, and can be greatly improved by applying high pressures to the feed side. The oxygen permeation flux of BSCF capillary membrane is up to 19.5 mL cm−2 min−1 when 0.5 MPa air was applied to the feed side at 900 °C, which is one order of magnitude higher than that of SDC-SSCF capillary membrane. Thus, both capillary membranes have their own advantages and meet applications under different operation conditions.

Simulation study on the performance of low-temperature water gas shift membrane reactor system

In order to understand the behavior of the low-temperature water gas shift (WGS) reaction membrane reactor system and obtain better performance of the reactor, numerical simulations are performed with a two-dimensional axisymmetric model. Dimensionless analysis is applied to the governing equations, and then a set of dimensionless parameters are established. The effect of the parameters of Damkohler number (Da) and membrane permeability (Pp) over a wide range on the performance of CO conversion and hydrogen recovery is studied, and the discussion of reaction phenomenon is presented. The WGS reaction is simulated under the operating conditions of 2 atm and two temperatures of 200 and 300 °C. The simulation results suggest that Da=10−4 and Pp=10−1 are the optimum operating conditions for the reactor system where the conversion reaches nearly 100% exceeding the thermodynamic equilibrium conversion by 11% at 300 °C and the optimal hydrogen recovery is achieved simultaneously. The distribution of components along the axis of the reactor is checked, and then two crucial indicators are raised to assess the extent of reaction and hydrogen separation respectively, for the purpose of guidance for the length design of the reactor. Finally, the analysis of the effect of sweep gas on reactor performance suggests that the optimum flow rate of sweep gas is 0.2–0.5 L/min, and further enhancement of performance can be achieved by using counter-current sweep gas configuration.

Modeling of dry reforming of methane for hydrogen production at low temperatures using membrane reactor

Abstract The hydrogen removal and carbon formation effects in dense palladium (Pd)-based membrane reactors for dry reforming of methane (DRM) performance is numerically analyzed in this study. The steady-state membrane reactor operation is described using a three-dimensional, heterogeneous, non-isothermal mathematical model. Based on the numerical simulation results for reaction temperature and pressure varied in the 400–600 °C and 1–30 atm ranges, methane conversion and hydrogen yield were found enhanced using the membrane reactor. However, carbon formation, which affects catalyst activity and limits the benefits of using a membrane reactor is also enhanced. A parametric study using reaction pressure as the primary parameter for the membrane reactor operation found that the CH4 conversion, hydrogen yield, H2 recovery, and carbon formation can be enhanced by increasing the reaction temperature, inlet CO2/CH4 ratio, and sweep gas flow rate. With the enhanced H2 removal, carbon formation is also enhanced. Because membrane permeance is inversely proportional to the membrane thickness, membrane thickness can be used as a parameter to control the carbon formation under given operating conditions.

Design improvement and experimental study on shell and tube condenser for bio-oil recovery from fast pyrolysis of wheat straw biomass

In this study, the design improvement was done in a shell and tube condenser for improved heat transfer and condensation of bio-oil vapour. The developed condenser has split shell and segmental baffles, which divide the shell in various zones and condensate collection points. The fast pyrolysis of wheat straw was done and the bio-oil vapour condensate collected from various outlets located at bottom of condenser shell. From experimental results it was found that production of bio-oil increased from 10.2 to 20.8% with increase in cooling water flow rate from 1000 to 2500 L/h; but, further increasing it beyond 2500 L/h provide marginal effects on production of bio-oil. The production of bio-oil increased from 15.2 to 20.7% as sweep gas flow rate was increased from 20 to 40 L/min at 2500 L/h of cooling water flow rate. But, further increase in sweep gas flow rate beyond 40 L/min resulted in to decrease in production of bio-oil. The novelty of this work is development of improved condenser with segmental baffles, which help in fractional condensation of bio-oil vapour, split shell for cleaning of outer surface of the cooling water tubes and compact design of condenser for optimal condensation of bio-oil.

Hydrogen production by solar steam methane reforming with molten salts as energy carriers: Experimental and modelling analysis

An innovative steam methane reforming for pure hydrogen production with molten salts as heat transfer fluid has been analyzed validating experimental data by means of a mathematical model. The technology, developed in the project CoMETHy and realized on a pilot scale at the ENEA-Casaccia research center, is based on a steam-reforming reactor with a structured open foam catalyst and Pd-based membranes, both integrated in the reaction environment to improve the reactor performance. The pilot plant allowed the production of ≥3 Nm3/h of pure hydrogen, achieving an overall methane conversion of 60% at < 545 °C reactor temperature. The mathematical model, composed of a partial differential equations set, has been solved by numerical simulation. The effects on pilot plant performance of some operating conditions, such as steam-to-carbon ratio, molten salt inlet temperature and sweep gas flow rate, have been investigated. The results obtained from model simulations have been compared to the available experimental data to validate the model. The average absolute error of the model is less than 2%.

Experimental implementation of a catalytic membrane reactor for the direct synthesis of DME from H2+CO/CO2

The direct synthesis of dimethyl ether (DME) by the hydrogenation of CO2 and CO2/COx mixtures has been studied in an original packed bed membrane reactor (PBMR). The role of the hydrophilic LTA zeolite membrane is to remove H2O from the reaction medium, reducing therefore the thermodynamic limitations of methanol synthesis and dehydration stages. LTA zeolite has the best permeation properties among the studied zeolites (LTX and SOD). The experiments were carried out using a CuO-ZnO-ZrO2/SAPO-11 catalyst at 275–325 °C, 10–40 bar, space time of 10 gcat h (molC)−1 and using in the permeate section a sweeping gas flowrate of the same composition as that fed to the reaction section. The results (DME yield, CO2 conversion and product distribution) of the PBMR are compared with those obtained in PBR without membrane. In the hydrogenation of CO2, a DME yield of 12% and a CO2 conversion of 20% are obtained at 275 °C, 40 bar and space time of 10 gcat h (molC)−1 with a great catalyst stability.

Hydrogen production by methane steam reforming using metallic nickel hollow fiber membranes

The metallic nickel hollow fiber membranes (NHFMs) consisting of a dense skin layer integrated on porous nickel substrate were fabricated in a single extrusion step by using a 90 wt% NMP-H2O solution and water as the respective internal and external coagulants during the spinning process. The resultant asymmetric Ni hollow fibers by sintering were directly applied to hydrogen production from methane steam reforming (MSR), where the porous internal surface functioned as a catalyst bed for MSR reactions, and the external dense skin layer served as the membrane for hydrogen extraction from the reaction products. The effects of the feed composition in terms of steam-to-methane ratio (H2O/CH4) and methane concentration; the operational parameters including temperature, space velocity, and the sweep gas flow rate on the performance of the hollow fibers were investigated. The results reveal that the reaction operational temperature should be above 800 °C and the H2O/CH4 ratio controlled around 3 so as to achieve both high methane conversion and high H2 production rate. When operated at 1000 °C and 25,937 h−1 methane space velocity, the maximum H2 production rate reached 50.84 mmol m−2 s−1 while the methane conversion reached at 98.58%. In order to produce pure hydrogen, steam may be used as the sweep fluid instead of inert gases such as nitrogen to prevent the dilution of the permeated gaseous hydrogen. The prepared asymmetric NHFMs also demonstrate high chemical stability in the reformate gases and high resistance to carbon deposition at above 800 °C, and thus may be a promising way of cost-effective hydrogen production by MSR at high temperatures.

Protocol-driven daily optimisation of venovenous extracorporeal membrane oxygenation blood flows: an alternate paradigm?

Venovenous extracorporeal membrane oxygenation (VV ECMO) is now an established modality of support for patients with the who are failing evidence-based conventional therapies. Minimising ventilator-induced lung injury is the guiding principle behind patient management with VV ECMO. Patients with acute respiratory distress syndrome (ARDS) supported with VV ECMO are liberated from ECMO at a stage when native lungs have recovered sufficiently to support physiologic demands and the risks of iatrogenic lung injuries after discontinuation of ECMO are perceived to be small. However, native lung recovery is a dynamic process and patients rely on varying degrees of contributions from both native lungs and ECMO for gas exchange support. Patients often demonstrate near total ECMO dependence for oxygenation and decarboxylation early in the course of the illness and this may necessitate higher ECMO blood flow rates (EBFRs). Although, reliance on high EBFR for oxygenation support may remain variable over the course of ECMO, blood flow requirements typically diminish over time as native lungs start to recover. Currently, protocol-driven modulation of the EBFR based on changing physiologic needs is not common practice and consequently patients may remain on higher than physiologically necessary EBFR. This exposes the patient to potential risks because maintaining higher blood flows often requires a less restrictive fluid balance and deeper sedation. Both may be harmful in the setting of recovery from ARDS. In this article, we propose a strategy that involves daily assessments of native lung function and a protocol-driven daily optimisation of EBFR. This is followed by optimisation of sweep gas flow rate (SGFR) and the fraction of delivered oxygen in the sweep gas (FdO2). This staged approach to weaning VV ECMO allows us to fully utilise the “decoupling” of oxygenation and decarboxylation that is possible only during extracorporeal support. This approach may benefit patients by allowing for greater fluid restriction, more aggressive fluid removal, expedited weaning of sedation and neuromuscular blocking agents (NMBAs), and early physical rehabilitation. Ultimately, prospective studies are needed to evaluate optimal VV ECMO weaning practices

A novel CFD simulation of H2 separation by Pd-based helical and straight membrane tubes

A novel three-dimensional CFD simulation of H2 gas permeation through dense palladium (Pd) membrane was developed. Due to discontinuity of flow in a membrane, usually, gas diffusion process is simulated by introducing source and sink terms. In a novel approach, an analogy between heat and mass transfer is considered. The most important advantage of this approach is that there is no need to define sink and source terms, and the membrane thickness is considered as a solution domain without separating the geometry adjacent to the membrane. Also, it allows the modeling of multilayer membranes with different mechanisms of diffusion, separately. The effect of membrane geometry on the hydrogen separation was investigated using the straight and helical modules by defining user-defined function (UDF) and user-defined scalars (UDS). The results showed an average flux and H2 recovery enhancement of 20% and 13% for helical configuration, respectively. The influence of the feed gas and sweep gas flow rates, helix pitch, coil diameter, pressure difference, and module temperature on hydrogen separation was also investigated. The proposed simulation model was validated using the experimental data. The results indicated that this method has a maximum error of about 10% for H2 flux.

A comparative study on valuable products: bio-oil, biochar, non-condensable gases from pyrolysis of agricultural residues

In this study, pyrolysis of agricultural residues, such as rice straw (RS), wheat straw (WS), and sugarcane bagasse (SB), was performed in a fixed-bed reactor. The experiments were carried out at varying operating conditions, such as temperature, heating rate, biomass particle size and sweeping gas flow rate, such that the bio-oil yield could be maximized. Small particle size and high heating rate contributed to more bio-oil yield as compared to large particle size and low heating rate. Physicochemical properties of bio-oil samples, evaluated in a comparative manner with maximum focus devoted on analyzing the chemical constituents through GC–MS and FTIR analysis. Biochar was also examined through different physicochemical techniques (e.g., HHV, pH, SEM–EDX, FTIR, CHNS, ICP-AES) for understanding pyrolysis mechanism and its practical usability. Analysis of non-condensable gas through GC-TCD, revealed co-existence of H2, CO, CO2 and CH4 molecules, with greater percentage of H2 and CH4 at high temperature resulted enhancement in calorific value.

A Systematic Framework for Optimizing a Sweeping Gas Membrane Distillation (SGMD).

The present work has undertaken a meticulous glance on optimizing the performance of an SGMD configuration utilized a porous poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP) membrane. This was carried out by conducting a systematic framework for investigating and optimizing the pertinent parameters such as sweeping gas flow rate, feed temperature, feed concentration and feed flow rate on the permeate flux. For this purpose, the Taguchi method and design of experiment techniques were harnessed to statistically determine optimum operational conditions. Besides that, a comprehensive surface and permeation characterization was conducted against the hand-made membranes. Results showcased that the membrane performance was ultimately controlled by the feed temperature and was nearly (~680) % higher when the temperature raised from 45 to 65 °C. Also, to a lesser extent, the system was dominated by the feed flow rate. As the adopted feed flow rate increases (from 0.2 to 0.6 L/min), around 47.5% increment was bestowed on water permeability characteristics. In contra, 34.5% flux decline was witnessed when higher saline feed concentration (100 g/L) was utilized. In the meantime, with raising the sweeping gas flow rate (from 120 to 300 L/h), the distillate was nearly 129% higher. Based on Taguchi design, the maximum permeate flux (17.3 and 17 kg/m2·h) was secured at 35 g/L, 0.4 L/min, 65 °C and 300 L/h, for both commercial and prepared membranes, respectively.

Pyrolysis of torrefied biomass: Optimization of process parameters using response surface methodology, characterization, and comparison of properties of pyrolysis oil from raw biomass

Pyrolysis of torrefied Acacia nilotica was investigated in a tubular fixed-bed reactor under nitrogen environment. The process was optimized using response surface methodology coupled with central composite design, in order to obtain the maximum yield of pyrolysis oil. The maximum yield of pyrolysis oil (33.59 wt %) was obtained at 507.04 °C, retention time of 58.25 min, heating rate of 38.00 °C/min, and sweeping gas flow rate of 40.52 mL/min. Analysis of variance confirmed that pyrolysis of torrefied biomass for maximum pyrolysis oil yield highly depended on temperature followed by heating rate, retention time, and sweeping gas flow rate, respectively. Pyrolysis of raw biomass was also carried out at the optimum condition for comparing the quality of both pyrolysis oils. The pyrolysis oil samples were subjected to FTIR, GC-MS, and 13C NMR analyses along with estimation of water content, pH, viscosity, HHV, etc., for comparing the physicochemical characteristics. Results showed that total aromatic carbon, carbonyl carbon, and primary alkyl carbon of pyrolysis oil from torrefied biomass increased by 40.28, 51.36, and 6.34%, respectively, as compared to pyrolysis oil from raw biomass. The phenol derivative compounds are increased by 18.91%. The HHV and pH of pyrolysis oil from torrefied biomass increased by 23.53, 42.15%, respectively, while water content decreased by 34.37% as compared to pyrolysis oil from raw biomass. Thus, with rapid advancement in pyrolysis process, the integrated approach of torrefaction-pyrolysis process may be beneficial to produce cleaner pyrolysis oil as compare to raw biomass.

Experimental investigation on the production of bio-oil from wheat straw

ABSTRACT The utilization of waste biomass such as crop residues in the production of biofuel is gaining attention from all around the world. The wheat is one of the most grown crops in the world and its main by-product straw produced 529 million tons per annum. The present study aims to investigate the feasibility of wheat straw as biomass material to produce bio-oil in a fluidized bed fast reactor. The developed system has a throughput capacity of 5 kg/h and the effect of varying temperature, biomass particle size, and sweep gas flow rate on the yield of pyrolysis products mainly on bio-oil is also studied. The result showed that the highest bio-oil yield 42 wt% was obtained at a temperature of 500°C, the feed particle size of 1 mm, and the gas flow rate of 4 m3/h. The properties of produced bio-oil were determined such as heating value, viscosity, and pH of 19.59 MJ/kg, 18.01 cP, and 3.1, respectively. The GCMS and FTIR analysis were used to identify the chemical compounds available on bio-oil and the phenol, alcohols, alkanes, alkenes, esters, furnol, hydrocarbon, and aromatic compounds were reported in the bio-oil. The economic assessment showed that the production cost of bio-oil was 0.50 US$/liter and the calculated payback period of the system was 1.57 years.

Characteristics of Oxygen Permeation and Partial Oxidation of Methane in a Catalytic Membrane Reactor for Syngas Production

In this study, the use of membranes for partial oxidation of methane (POM) for syngas production is investigated numerically in a catalytic membrane reactor (CMR). The reactor considers using a multilayer oxygen-permeable membrane made of macroporous Ni–Al foam substrate in the presence of LaNi0.9Pt0.1O3 catalyst. The CMR was fed with air in one side and a mixture of fuel (CH4) and helium in the sweep side. Because of its symmetry, half of the domain was meshed in the full three-dimensional (3-D) domain and ANSYS-2019-R2 was used to perform the numerical simulations. For modeling oxygen permeation across the membrane, a source/sink term was created in mass and momentum equations using a series of user-defined functions (in C++) to be compiled and attached to the software. The indirect approach for methane conversion into syngas was adapted in the numerical model considering steam and dry reforming reactions. The model was validated using the available literature experimental data on the same CMR. The simulations were performed over ranges of operating parameters in order to improve the performance of the CMR for syngas production. The effects of sweep fuel concentration, feed air flow rate, and sweep gas flow rate on CMR performance were investigated. The results showed that increasing sweep fuel concentration reduces its conversion. All reactions were quenched in the outlet tube, because of the increased flow velocity and lack of O2. The counter-current flow configuration resulted in much better selectivities of CO and H2, compared to the cases of cocurrent flow configuration (89% and 73%, compared to 38% and 23%, respectively). The increase of oxygen concentration at the permeate side of the membrane while increasing the feed air flow rate leads to a reduction of syngas selectivity, along with an increase in fuel conversion. The fuel conversion showed a sharp reduction from ∼53% to ∼5% for an increase in sweep gas flow rate from 5 L/h to 30 L/h at a fixed sweep fuel concentration of 10% (by volume). The selectivities of CO and H2 decrease to <5% for sweep flow rates of >30 L/min. This indicates insufficient availability of oxygen for fuel conversion at higher sweep gas flow rates, because of reduced temperature within the CMR. For sweep flow rates of >30 L/h, the gas temperature even cools in the axial direction toward the membrane, resulting in deteriorated performance of the CMR.

Extracorporeal Life Support Organization (ELSO): Guidelines for Neonatal Respiratory Failure.

Extracorporeal Life Support Organization (ELSO): Guidelines for Neonatal Respiratory Failure.