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This research on biodiesel production aims to improve energy processes to advance towards a sustainable economy. This study focuses on improving the biodiesel conversion efficiency in a helical tubular reactor coupled with a static mixer. A 23 factorial design was used to evaluate how variables such as the molar ratio of alcohol–oil (4:1–8:1), residence time (4–8 min), and catalyst concentration (0.5–1 wt%) affect the transesterification process. Soybean oil and methanol were used, with NaOH as a catalyst at 60 °C. The results show that the residence time and catalyst concentration are key factors in increasing biodiesel production by up to 10%. An experimental yield of 84.97% was obtained with a molar ratio of 6:1 alcohol–oil, 0.9 wt% NaOH, and a reaction time of 6 min. The experimental design predicted a yield of 91% with a molar ratio of 4:1 alcohol–oil, 1 wt% NaOH, and a reaction time of 8 min, with a deviation of 1.88% from the experimental values. The fit of the experimental model was R2 = 0.9632. These findings are valuable for improving the transesterification process and the development of biodiesel in continuous flow reactors. [ABSTRACT FROM AUTHOR]

The proper selection of a relevant mixer generally requires an effective assessment of several models against the application requirements. This is a complex task, as traditional evaluation methods generally focus only on a single aspect of performance, such as pressure loss, mixing characteristics, or heat transfer. This study assesses a urea-based selective catalytic reduction (SCR) system installed on a ship, where the installation space is limited and the distance between the urea aqueous solution injection position and the reactor is low; therefore, the static mixer installed in this pipeline has special performance requirements. In particular, four evaluation indices are used in this study: The B value, C value, pressure loss correction factor (Z′), and the ratio of the required distance to the equivalent diameter of the pipe (LV/D) when the velocity field after the mixer attains uniformity. Six types of static mixers were simulated with varying concentrations, flow speeds, and positions. A fuzzy comprehensive evaluation method was introduced to evaluate and compare the related advantages and disadvantages. The results showed that 1) mixing performance was related to the shape of the mixer and had no direct relationship with flow velocity. 2) For the same mixer position, the lower the urea concentration, the greater the difficulty of evenly mixing the solution. 3) At a constant urea concentration, the mixing performance improved when the mixer was closer to the injection inlet. 4) The installation of a GK mixer in the SCR system of a 9L20C diesel engine was best. [ABSTRACT FROM AUTHOR]

Nitration of O-methylisouronium sulfate under mixed acid conditions gives O-methyl-N-nitroisourea, a key intermediate of neonicotinoid insecticides with high application value. The reaction is a fast and highly exothermic process with a high mass transfer resistance, making its control difficult and risky. In this paper, a homogeneous continuous flow microreactor system was developed for the nitration of O-methylisouronium sulfate under high concentrations of mixed acids, with a homemade static mixer eliminating the mass transfer resistance. In addition, the kinetic modeling of this reaction was performed based on the theory of NO2+ attack, with the activation energy and pre-exponential factor determined. Finally, based on the response surface generated by the kinetic model, the reaction was optimized with a conversion of 87.4% under a sulfuric acid mass fraction of 94%, initial reactant concentration of 0.5 mol/L, reaction temperature of 40 °C, molar ratio of reactants at 4.4:1, and a residence time of 12.36 minutes.

A novel static mixer is designed specifically to blend hydrogen into natural gas pipelines, and its effectiveness is validated by numerical simulation method. Firstly, the structural model of the proposed static mixer model for hydrogen-methane blending is introduced, and the evaluation indicators are defined. Secondly, the computational fluid dynamic model for the mixing process is established based on the Large Eddy Simulation(LES) method, and the accuracy of the numerical results is validated against the experimental data of a benchmark gas mixing model. Subsequently, using LES, effects structural parameters (angle and height of trapezoidal baffle, number of mixing elements, and spacing and installation distance of mixing elements) and flow parameters (main flow velocity and hydrogen blending ratio) on the mixing homogeneity and pressure drop of the static mixer are investigated systematically to explore the optimal design and operational conditions. The numerical results showed that the static mixer can significantly improve the mixing efficiency of hydrogen and natural gas with acceptable pressure loss. In the range of flow conditions concerned, a best performance of mixing could be obtained by installing the mixer at a distance of 3 D (D is the diameter of the natural gas pipeline) downstream the blending point, setting the spacing between mixing elements as 1 D and employing four mixing elements. Finally, the underlying physics of mass transportation are analyzed based on the vortex structures generated by the mixer. • A novel static mixer is designed to blend hydrogen into natural gas pipelines. • A Large eddy simulation solution procedure is proposed to solve multi-component mixing. • Effects of key parameters of the static mixer and operating conditions are revealed. • The mixing mechanism of static mixer is revealed based on vortex dynamics analysis. [ABSTRACT FROM AUTHOR]

In this work, we analyzed the influence of four connection types of Kenics static mixer, namely direct connection static mixer (DSM), transition blade static mixer (TSM), plug-in static mixer (PSM) and solder joints static mixer (SSM) on the mixing performance. The effects of transition blade diameter, groove depth and solder joint diameter on segregation scale (S) and pressure drop (Δp) were studied. The results indicated that a better mixing performance and Δp were found in the mixers of DSM and three other smallsized connection types. The smallest Δp of 1.29 MPa were found in DSM, TSM3 and SSM2. The smallest S of 0.101 mm were found in PSM0.5. In addition, Δp and S increased as the connection size increases, in TSM, PSM and SSM. The agglomeration of particles was obvious in TSM and PSM with large connection sizes, but not in SSM. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Petrochemical Universities / Shiyou Huagong Gaodeng Xuexiao Xuebao is the property of Journal Editorial Department Of Liaoning Shihua University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Blending a specific proportion of hydrogen into a natural gas (NG) pipeline network is an effective strategy for achieving long-distance, large-scale, and cost-effective hydrogen transport. Static mixers played a crucial role in this process. In this study, a coaxial shear static mixer with ring-shaped structures instead of turbulence elements is proposed. The mixer exhibited favorable mixing performance and low pressure loss. The flow characteristics of NG and hydrogen within the mixer were investigated with computational fluid dynamics (CFD) methods. The effects of the number of cavities, hydrogen pipe diameter, hydrogen blending ratio and pressure on the mixer performances were investigated, taking into account both mixing uniformity and pressure loss. When the number of cavities in the coaxial shear mixer increases to 48, the mixing uniformity reaches 95.43% (SMX is 95%), and the pressure loss is 67.02 Pa (SMX is 500 Pa). • High mixing uniformity and low pressure loss in the new coaxial shear mixer. • Effects of structural and operating parameters on mixer performance analyzed. • Coaxial shear mixer performs better than SMX mixer. [ABSTRACT FROM AUTHOR]

An uneven mixing of hydrogen-blended natural gas will lead to hydrogen embrittlement in distribution pipelines, thereby affecting the quality of terminal gas, and thus highlighting the importance of ensuring the uniformity of hydrogen and natural gas mixing. In this study, FLUENT software was used to simulate three different hydrogen filling modes, namely, T-tube, bending-tube, and static mixer, and the mechanisms underlying the mixing of hydrogen and natural gas under different filling modes were analyzed. In addition, we assessed the influences of gas velocity, hydrogen blending ratio, and mixer length and blade angle on the mixing effects of a static mixer. The results revealed that among the three mixing methods assessed, the static mixer has the best overall mixing effect. Increasing gas velocity was found to have no significant effect on the mixing of hydrogen and natural gas. With an increase of hydrogen blending ratio, the mixing uniformity of hydrogen and natural gas increased from 99.49% to 99.95%, whereas there was an increase from 84.12% to 99.05% when the length of static mixer was increased, and an increase from 59.53% to 99.78% in response to an increase in blade angle. Our findings in this study can provide a methodological reference for increasing the mixing uniformity of hydrogen and natural gas in hydrogen-blended natural gas pipeline networks, and thereby contribute to the safe and rapid development of the hydrogen energy industry. [ABSTRACT FROM AUTHOR]

This report is focused on understanding the mixing performance of Newtonian and non‐Newtonian fluids in an SMX static mixer through computational fluid dynamics (CFD) study in Simcenter STAR‐CCM+. For this, the standard SMX mixer with four mixer elements of radius 26 mm was chosen. The aspect ratio (L/D) was taken as 1. The model constructed was compared using pressure drop ratio values available in literature. First, the design was validated for Newtonian fluid, then for shear‐thinning fluid (non‐Newtonian). Mixing patterns produced through particle tracking approach revealed how blending improved as the fluid moved downstream and interacted with increasing number of mixer elements. A sensitivity study was undertaken to investigate the effect of particle injection mechanism on the mixing process. Two injection methods, vertical and horizontal, were explored to check the influence of injection position on mixing. The results indicate that for the given configuration irrespective of the injection location, at least four mixing elements are needed to achieve good mixing for both Newtonian and shear‐thinning fluids investigated in this study. Statistical reports were used to quantify mixing to understand the mixing behaviour for Newtonian and non‐Newtonian fluids with change in Reynolds number. At high Reynolds number, non‐Newtonian fluids exhibited better mixing abilities. Further, efforts were taken to optimize the various design parameters to produce the most optimum solution with a single mixer element for Newtonian fluid. [ABSTRACT FROM AUTHOR]

An uneven mixing of hydrogen-blended natural gas will lead to hydrogen embrittlement in distribution pipelines, thereby affecting the quality of terminal gas, and thus highlighting the importance of ensuring the uniformity of hydrogen and natural gas mixing. In this study, FLUENT software was used to simulate three different hydrogen filling modes, namely, T-tube, bending-tube, and static mixer, and the mechanisms underlying the mixing of hydrogen and natural gas under different filling modes were analyzed. In addition, we assessed the influences of gas velocity, hydrogen blending ratio, and mixer length and blade angle on the mixing effects of a static mixer. The results revealed that among the three mixing methods assessed, the static mixer has the best overall mixing effect. Increasing gas velocity was found to have no significant effect on the mixing of hydrogen and natural gas. With an increase of hydrogen blending ratio, the mixing uniformity of hydrogen and natural gas increased from 99.49% to 99.95%, whereas there was an increase from 84.12% to 99.05% when the length of static mixer was increased, and an increase from 59.53% to 99.78% in response to an increase in blade angle. Our findings in this study can provide a methodological reference for increasing the mixing uniformity of hydrogen and natural gas in hydrogen-blended natural gas pipeline networks, and thereby contribute to the safe and rapid development of the hydrogen energy industry.

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hydrogen-enriched compressed natural gas (HCNG) technology is one of the most critical developments in the natural gas industry. To ensure the safe utilization of HCNG, the mixing effect of the two gases must be characterized and evaluated. In this paper, five types of static mixers were developed and numerically simulated. The results showed that the velocity, hydrogen blending ratio (HBR), mixer types, element aspect ratio, torsion angle, and number of elements affected the mixing effect to different degrees. Specifically, the increase in velocity and HBR improved the mixing uniformity of hydrogen and methane, but with a limited impact. Additionally, the mixing uniformity increased with the increase in the torsion angle and the number of elements, as well as the decrease in the element aspect ratio. Overall, the torsion angle had the most significant effect on mixing uniformity. Comparing the five types of static mixers, it was found that the new LPD static mixers yielded the best mixing effect, while the Y-type static mixers had the worst mixing effect. It is noted here that all the static mixers could satisfy the mixing uniformity requirements of industrial production. [Display omitted] • The influence of five models on the gas mixing effect is comprehensively analyzed. • The gas mixing effect is analyzed by three evaluation indexes. • The effects of operating conditions and spoilers on the mixing effect are studied. • The new LPD static mixer has the best effect on gas mixing. [ABSTRACT FROM AUTHOR]

Electric desalination units in the crude oil refining process are becoming increasingly important with the growing trend towards heavy and poor crude oils. The oil–water mixing effect of the static mixer plays a crucial role in the electric desalination process. The present study investigated the effect of various variables, such as mixer type, number of mixing elements, washing water consumption, and oil viscosity and density on the oil–water mixing efficiency of a static mixer. In addition, this study also analyzed the effect of these variables on the salt washing process that occurs during mixing using a kinetic equation for the dissolution of inorganic salts. The results showed that the number of mixing elements was the most significant variable, followed by the amount of washing water injected. The density of the crude oil had a negligible effect. Based on these results, the use of four mixing elements in the SMX static mixer was recommended. The injection of washing water should be controlled at about 8%, while ensuring that the interfacial tension between oil and water remains below 0.01 N/m. Under these conditions, the salt washing efficiency reached 46.3%. This study provides a theoretical basis for designing static mixers and optimizing their operation in electric desalination processes. [ABSTRACT FROM AUTHOR]

This study investigates continuous biodiesel production from refined palm oil (RPO) using a 250-cm-length double-pipe static mixer (DPSM), mixing elements were employed first with the low-pressure drop static mixer (LPD-SM) and second with the Kenics Static Mixer (K-SM). Four key independent parameters in the transesterification reaction - methanol (MeOH) to RPO molar ratio, KOH concentration, static mixer length, and residence time - were optimized to achieve the desired methyl ester content (%E, wt.%), set at 96.5 wt.%. From response surface methodology (RSM), The optimal conditions of LPD-SM were MeOH to RPO molar ratio at 5:1, KOH concentration at 0.76 wt.% of RPO, 250 cm static mixer length, and 7.7 min residence time. Conversely, K-SM showed optimal conditions with MeOH to RPO molar ratio at 5.5:1, KOH concentration at 0.81 wt.% of RPO, 250 cm static mixer length, and 7.2 min residence time. Statistical analysis revealed KOH concentration as the most influential parameter, followed by residence time, static mixer length, and MeOH to RPO molar ratio, respectively. In summary, LPD-SM outperformed K-SM in reducing the amount of alcohol and catalyst consumption while maintaining %E at the set point, highlighting its potential as an efficient, sustainable approach for biodiesel production from RPO using a DPSM. [ABSTRACT FROM AUTHOR]

Purpose: The growing demand for effective pharmaceutical treatments, notably amidst health challenges like COVID, highlights the urgency for improved drug production techniques. This study examines the simulation of the Sulzer SMX static mixer in laminar conditions for the continuous pharmaceutical manufacturing of significant pharmaceuticals, notably imatinib. Methods: Computational fluid dynamics (CFD) were employed to assess the SMX static mixer’s hydrodynamics and mixing performance. Emphasis was on mixing efficiency and residence time distributions (RTD) in a mixer with SMX elements. We refined the model’s reliability and explored the correlation between friction factor and Reynolds number. The Definitive Screening Design (DSD) was used to determine major factors impacting mixer dynamics. Results: We established a novel correlation between friction factor and Reynolds number. The study reveal that lower flowrates significantly impact mixing efficiency, with different solvents inducing mixing delays. The RTD study identified the total inlet flowrate’s influence on distribution, with higher flowrates leading to more distinct RTD profiles and decreased axial mixing. The screening analysis highlighted flowrate’s dominance over other factors in determining mixing efficiency and residence time. Conclusions: Through precise computational fluid dynamics (CFD) simulations, the study affirms the robustness of the developed model and underscores the novel correlation between the friction factor and Reynolds number. Insights into flow rate’s pivotal role in dictating mixer efficiency and residence time distribution are discerned, culminating in a comprehensive guide for refining static mixer operations for optimized drug manufacturing. [ABSTRACT FROM AUTHOR]

This study analyzes the improvement of mixture homogeneity between natural gas and hydrogen within a pipeline by inserting a static mixer inside. Recurring to Ansys Fluent, three different cases were simulated to test the mixing. The performance of an helicoidal mixer (KMS) and a KVM mixer were analyzed and compared to the standard T-junction without static mixer. The required distance for achieving a homogeneous mixture, measured by the coefficient of variation (COV), was calculated and compared with the resulting pressure loss. The three cases were analyzed for hydrogen injection percentages until 20 % and for a gas pipeline connecting the transmission line to the distribution line (P = 18 bar). The use of static mixers facilitates a faster homogenization of the mixture. Among these mixers, the KVM mixer performed the best, achieving a homogeneous mixture over a shorter distance while incurring a lower pressure loss. • The Hydrogen injection in the natural gas network is presented with the review. • The homogenization of the mixture of hydrogen and methane in a pipe was evaluated. • CFD analysis to study the use of static mixers to enhance the mixture homogeneity. • Improved mixture homogeneity achieved by using static mixers. • The use of a KVM mixer is suggested. [ABSTRACT FROM AUTHOR]

Aiming at the problem that the suction chamber of the gas‐driven jet pump has insufficient mixing of the power gas and the sucked fluid leading to efficiency reduction, this study proposes to effectively combine the static mixer with the annular jet pump and design a new type of annular jet pump and apply it to the gas wells to improve the fluid recovery capacity. Numerical simulations based on the gas–liquid two‐phase flow model are carried out for a conventional annular jet pump (CAJP) and a new annular jet pump (NAJP). The reliability of the simulation results is verified by gas–liquid two‐phase flow experiments, and the differences between the two in terms of velocity, pressure loss, and turbulent kinetic energy are analyzed. Meanwhile, the validity of NAJP is verified, and the effects of different structures such as static mixer torsion angle, suction chamber angle, and area ratio on the performance of NAJP are analyzed. The results show that NAJP enhances the degree of mixing between the sucked fluid and the power gas through the cyclonic effect created by the static mixer compared with CAJP. It results in a 10.6% year‐on‐year increase in the velocity of the sucked fluid, a 3% year‐on‐year increase in the pressure drop, and a 12.2% year‐on‐year increase in efficiency. NAJP can significantly improve the fluid‐carrying performance. With a mixer angle of 210°, a suction chamber angle of 21°, and an area ratio of 1.77, the NAJP achieves an efficiency of 39.7%, which is a year‐on‐year increase of 7.3% compared to the structure under the same conditions before optimization. This study lays a foundation for the determination of the optimal design scheme of the annular jet pump and at the same time can provide theoretical and technical support for researchers in related fields. [ABSTRACT FROM AUTHOR]

This article deals with the mixing of a Newtonian material with a strongly viscous (nonNewtonian) material in a pipe with a static mixer. This problematic has a practical application in the food industry. CFD software ANSYS Fluent was used for numerical modeling. The mathematical model is defined using the basic balance equations, including the equation for species. The viscosity for a non-Newtonian highly viscous material (the working material) is defined using the Herschel-Bulkley model. A 3D computational model of a pipe with a static helical mixer is created in the DesignModeler program, which is part of the ANSYS software. The computational mesh was created in the Fluent Meshing program. The CFD modeling analysis is implemented for two different pipe diameters and different flow rates at the pipe inlet. The evaluation of the results is processed by the ANSYS Fluent program using the distribution of basic quantities and graphs. [ABSTRACT FROM AUTHOR]

ObjectiveAiming at the phenomenon of uneven distribution or large accumulation of water in the transportation process of water-cut crude oil, the Kenics static mixer was introduced into the transportation process of water-cut oil, and the homogenization effect was analyzed. Methods FLUENT software was used to simulate the flow field inside the pipeline, and the homogenization effect was evaluated by coefficient of variation and average droplet size. The effects of mixing unit arrangement, twist angle, aspect ratio, and quantity on the homogenization effect were analyzed. ResultsThe use of Kenics static mixers with staggered arrangement, twist angle of 240°, length to diameter ratio of 0.5, and number of 10 can not only achieve uniform distribution of the oil-water phase, but also achieve smaller average droplet size, thereby achieving better homogenization effect. ConclusionsThe best homogenization effect was achieved when the arrangement method was opposite and staggered. With the increase of torsion angle, the variation coefficient at the pipeline outlet and the average droplet size show a downward trend. With the decrease of aspect ratio and the increase of quantity, the coefficient of variation values at the outlet tend to be the same, but smaller average droplet sizes can be obtained. After homogenization treatment, the samples can more accurately reflect the water content of the crude oil in the storage tank, avoid disputes over oil handover, and ensure the completion of the oil export task. [ABSTRACT FROM AUTHOR]

Static mixers are widely used in selective catalytic reduction (SCR) systems to improve the conversion efficiency and service life of the catalyst by better mixing ammonia and the exhaust stream. However, the structure of the mixer needs to be designed carefully to minimise the loss of the system pressure caused by its installation. In this work, experiments and simulations are conducted to evaluate the mixing performance of the static mixers and the system pressure loss. The simulations and experimental results have good agreement. Four novel static mixers are designed and compared with a commercial static mixer to demonstrate their performance. The results show that the box mixer can accomplish less pressure loss (690 Pa) and more homogenous mixing (CoV = 5.4%), and it can thus be used to improve the mixing of ammonia and the exhaust stream in SCR systems. [ABSTRACT FROM AUTHOR]

This study presents a specialized mixer design for gas burners aimed at improving the efficiency of phase mixing while minimizing system resistance and energy consumption. The proposed design utilizes a multi‐cavity mixer employing both radial and axial mixing techniques, eliminating the need for additional power supply. Full premixed combustion of small gas‐fired industrial boiler has the function of "inhibiting" NOx emission from the source, and good mixing of fuel and combustion supporting air in the early stage is the primary prerequisite for realizing full premixed combustion denitration. In this article, a radial multichamber static mixer is designed following the characteristics of full premixed mixing in gas‐fired industrial boilers. The results demonstrate that the maximum pressure drop of the static mixer is 806 Pa; for gas and air branch pipes, the resistance coefficient f decreases rapidly with the increase in Reynolds number; when Re ≥ 1.2 × 103, the resistance coefficient in the air branch pipe decreases slowly; when Re ≥ 4.5 × 103, the resistance coefficient of gas branch pipe decreases slowly. Additionally, the maximum calculation error of symmetrical gas branch pipe is 9.1%. The static mixer's inlet exhibits a converted velocity of 24 m/s, and the outlet demonstrates an airflow velocity of 23.2 m/s. As a result, a kinetic energy loss of 6.5% is observed. The static mixing chamber makes the airflow rotate and causes different gases to shear and mix. The mixing channel has the function of correcting the airflow deviation, especially for the sudden expansion section. Generally, the two gases can be mixed evenly at the outlet of the mixer. The standard k‐e model and realizable k‐e model are employed to simulate the sudden expansion channel, and indicate that the standard k‐e has a wider range of influence. Further investigation is recommended to better comprehend and optimize this particular area of influence. [ABSTRACT FROM AUTHOR]

Abstract In the process of natural gas extraction, the phenomenon of liquid loading will affect the efficiency of gas well extraction and reduce the life of the well. Compared with conventional drainage gas extraction technology, the jet pump can not only reduce the bottom back pressure and ensure the stable production of gas reservoirs but also promote the final recovery rate. Since the jet pump relies on the interaction between fluid particles to transfer energy, the energy loss is large and the efficiency is low. To maximize the advantages of the gas‐driven jet pump, this study innovatively combines a static mixer with an annular jet pump. Utilizing the cyclonic effect produced by the static mixer, the original gas‐liquid axial motion is transformed into a stronger vortex motion, and the liquid droplets are changed into a liquid film that is easier to carry, which significantly improves the discharge efficiency of the jet pump. This study uses a combination of numerical simulation and experimental analysis to compare the associated effects of the new annular jet pump (NAJP) and the conventional annular jet pump (CAJP) on the liquid‐carrying performance of gas wells in terms of cyclonic effect, droplet breakage ratio, and pump efficiency. The results show that, compared with CAJP, NAJP increases the mass flow rate of the sucked fluid. The droplet breakage ratio increases by 15.4% year‐on‐year, while the critical liquid‐carrying flow rate is reduced by about 10.7%, resulting in a maximum pumping efficiency of 37%, an increase of about 30.7% year‐on‐year. At the same time, the reduction of the energy coefficient means lower energy consumption. In summary, NAJP is better than CAJP in terms of liquid‐carrying effect and efficiency.

Abstract This study presents a specialized mixer design for gas burners aimed at improving the efficiency of phase mixing while minimizing system resistance and energy consumption. The proposed design utilizes a multi‐cavity mixer employing both radial and axial mixing techniques, eliminating the need for additional power supply. Full premixed combustion of small gas‐fired industrial boiler has the function of “inhibiting” NOx emission from the source, and good mixing of fuel and combustion supporting air in the early stage is the primary prerequisite for realizing full premixed combustion denitration. In this article, a radial multichamber static mixer is designed following the characteristics of full premixed mixing in gas‐fired industrial boilers. The results demonstrate that the maximum pressure drop of the static mixer is 806 Pa; for gas and air branch pipes, the resistance coefficient f decreases rapidly with the increase in Reynolds number; when Re ≥ 1.2 × 103, the resistance coefficient in the air branch pipe decreases slowly; when Re ≥ 4.5 × 103, the resistance coefficient of gas branch pipe decreases slowly. Additionally, the maximum calculation error of symmetrical gas branch pipe is 9.1%. The static mixer's inlet exhibits a converted velocity of 24 m/s, and the outlet demonstrates an airflow velocity of 23.2 m/s. As a result, a kinetic energy loss of 6.5% is observed. The static mixing chamber makes the airflow rotate and causes different gases to shear and mix. The mixing channel has the function of correcting the airflow deviation, especially for the sudden expansion section. Generally, the two gases can be mixed evenly at the outlet of the mixer. The standard k‐e model and realizable k‐e model are employed to simulate the sudden expansion channel, and indicate that the standard k‐e has a wider range of influence. Further investigation is recommended to better comprehend and optimize this particular area of influence.

In the process of natural gas extraction, the phenomenon of liquid loading will affect the efficiency of gas well extraction and reduce the life of the well. Compared with conventional drainage gas extraction technology, the jet pump can not only reduce the bottom back pressure and ensure the stable production of gas reservoirs but also promote the final recovery rate. Since the jet pump relies on the interaction between fluid particles to transfer energy, the energy loss is large and the efficiency is low. To maximize the advantages of the gas‐driven jet pump, this study innovatively combines a static mixer with an annular jet pump. Utilizing the cyclonic effect produced by the static mixer, the original gas‐liquid axial motion is transformed into a stronger vortex motion, and the liquid droplets are changed into a liquid film that is easier to carry, which significantly improves the discharge efficiency of the jet pump. This study uses a combination of numerical simulation and experimental analysis to compare the associated effects of the new annular jet pump (NAJP) and the conventional annular jet pump (CAJP) on the liquid‐carrying performance of gas wells in terms of cyclonic effect, droplet breakage ratio, and pump efficiency. The results show that, compared with CAJP, NAJP increases the mass flow rate of the sucked fluid. The droplet breakage ratio increases by 15.4% year‐on‐year, while the critical liquid‐carrying flow rate is reduced by about 10.7%, resulting in a maximum pumping efficiency of 37%, an increase of about 30.7% year‐on‐year. At the same time, the reduction of the energy coefficient means lower energy consumption. In summary, NAJP is better than CAJP in terms of liquid‐carrying effect and efficiency. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Engineering of Oil & Gas / Shi You Yu Tian Ran Qi Hua Gong is the property of PetroChina Southwest Oil & Gas Field Company and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The work considers the results of experimental and numerical study on the hydrodynamic characteristics of a jet vortex reactor, MicroReactor with Intensively Swirled Flows MRISF-1, for which one of the application fields is the synthesis of oxide materials (e.g., perovskite-like material for solar panels). The energy-dissipation rate and micromixing quality are studied (by the iodide–iodate method) for various methods of supplying MRISF-1 and T-shaped millireactors with solutions. Numerical modeling reveals the volumes with the highest energy-dissipation rate. The quality of micromixing in the MRISF-1 is shown to be much higher than in the T-shaped millireactor, due to, among other things, the fact that the zone with the highest energy-dissipation rate is localized near the neck of the MRISF-1. [ABSTRACT FROM AUTHOR]

The current mixers in the compressed air foam system used to generate liquid foam have high flow resistance. Kenics static mixer may be a better choice for making foam because its spiral structure can lower the flow resistance. However, the effects of the structure of Kenics static mixer on the properties of liquid foam remain unclear. The primary objective of this work is to study the influences of aspect ratio, transition angle, and the number of elements of Kenics static mixer on foaming performance and make the structural design optimization. The results indicated that the aspect ratio of the Kenics static mixer had the greatest impact on the foam properties, followed by the number of elements, and the transition angle had the smallest impact. The velocity distributions were distinct at the same relative position for different aspect ratios. When the number of elements exceeded four, the increase in the number of elements hardly changed the velocity distributions. The results also emphasized the critical role of velocity distribution in improving the coefficient of variation and elucidated a strong correlation between the coefficient of variation and foaming performance. The findings can offer guidance for the optimal design of the foam generator. [ABSTRACT FROM AUTHOR]

Removing excessively produced cytokines is of paramount significance in blood purification therapy for hypercytokinemia-associated diseases. In this study, we devised a conduit that is modified with nanobodies (Nb) and incorporates static mixers (Nb-SMC) to eliminate surplus cytokines from the bloodstream. The low-pressure-drop (LPD) static mixer, with each unit featuring two 90°-crossed blades, was strategically arranged in a tessellated pattern on the inner wall of the conduit to induce turbulent mixing effects during the flow of blood. This arrangement enhances mass transfer and molecular diffusion, thereby assisting in the identification and elimination of cytokines. By utilizing computational fluid dynamics (CFD) studies, the Nb-SMC was rationally designed and prepared, ensuring an optimal interval between two mixer units (H/G = 2.5). The resulting Nb-SMC exhibited a remarkable selective clearance of IL-17A, reaching up to 85 %. Additionally, the process of Nb immobilization could be adjusted to achieve the simultaneous removal of multiple cytokines from the bloodstream. Notably, our Nb-SMC displayed good blood compatibility without potential adverse effects on the composition of human blood. As the sole documented static mixer-integrated conduit capable of selectively eliminating cytokines at their physiological concentrations, it holds promise in the clinical potential for hypercytokinemia in high-risk patients. High-efficient cytokines removal in critical care still remains a challenge. The conduit technique we proposed here is a brand-new strategy for cytokines removal in blood purification therapy. On the one hand, nanobody endows the conduit with specific recognition of cytokine, on the other hand, the build-in static mixer enhances the diffusion of antigenic cytokine to the ligand. The combination of these two has jointly achieved the efficient and specific removal of cytokine. This innovative material is the only reported artificial biomaterial capable of selectively eliminating multiple cytokines under conditions close to clinical practice. It has the potential to improve outcomes for patients with hypercytokinemia and reduce the risk of adverse events associated with current treatment modalities. [Display omitted] [ABSTRACT FROM AUTHOR]

An ideal static mixer can achieve efficient mixing at low pressure drops. Owing to the excellent performance of the tridimensional rotational flow sieve tray (TRST) in a gas–liquid two‐phase system, the TRST structure was modified into a rotational–perforated static mixer (RPSM) to enhance mixing in multicomponent liquid systems. The energy consumption characteristics of the RPSM were experimentally studied based on Reynolds numbers in the range of 986–7892, gap L = 0–80 mm, and relative angle γ = 0–45°. The effects of the element installation method, number, gap, relative angle, fluid Reynolds number, fluid properties, and other parameters on the RPSM pressure drop were also investigated. An interaction analysis of each factor was performed using the factorial design method and an empirical model of the RPSM Z‐factor was established. Additionally, pressure drop in the RPSM was compared with those of other commonly used static mixers. Results show that, when the element is backward‐installed, the pressure drop is higher than that in the forward direction because the fluid is constantly twisted. Moreover, the pressure drop increases with increasing element gap, and the average increase is 43.64% and 19.28% for the forward and backward installations, respectively. The influence of the relative angle on the pressure drop is mainly reflected when the gap L = 0. Subsequently, the degree of influence of each factor was determined, and the Z‐factor was calculated and found to be consistent with the experimental values (relative error of less than 15%). [ABSTRACT FROM AUTHOR]

A new selective catalytic reduction (SCR) system for captive power plants in the petrochemical industry was analyzed. The key components suitable for the target SCR system were obtained using computational fluid dynamics (CFD) numerical simulation combined with a cold physical model. The structural characteristics of the SCR system were studied, and corresponding design schemes were obtained for the key components, such as the guide plate, the ammonia injection grid (AIG), the static mixer, and the rectifier grille. The distributions of the flue gas velocity and the NH3 concentration within the flue cross-section in front of the first layer catalyst were studied in detail. Synchronously, the pressure loss and the temperature reduction characteristics in the SCR system were also considered. CFD results showed that the average standard deviation of the flue gas velocity was about 11.61%, and the average standard deviation of the NH3 concentration distribution could reach about 3.79% under the five operating conditions. It could be concluded that the uniformity of the flue gas velocity and the NH3 concentration distribution within the above flue cross-section was guaranteed by comparing to the design standard of 15% and 5%, respectively. It was further found that the maximum pressure loss between the inlet and the first layer catalyst was about 106.64 Pa, and the temperature reduction characteristic of the entire SCR system could be maintained within ±0.01 °C, which indicated that no extreme adverse effect arose due to the introduce of the key components. The cold physical model experiment was accordingly conducted to verify the reliability of the above CFD results. The cold physical model experiment results showed that the average standard deviation of flue gas velocity was about 8.82%, and the average standard deviation of NH3 concentration distribution could reach about 4.21%. The maximum biases for the standard deviations of the flue gas velocity and the NH3 concentration distribution were approximately 4.83% and 1.18% under the five operating conditions. Based on the good agreement of the research results via the two different methods, the designed key components of a new SCR system could be confirmed to be feasible, which would benefit the deNOx performance of the SCR system. [ABSTRACT FROM AUTHOR]

Hydrogen, as a carbon-free fuel, is significantly for replacing fossil fuels and reaching the ultimate goal of carbon neutrality, and is commonly expected to play a major role in future energy supply. Blending hydrogen into natural gas pipeline networks for end-user consumption as a means of delivering pure hydrogen to the market which not only improves the utilization rate of hydrogen energy, but also reduces the cost of hydrogen transportation. A three-dimensional model of the blending the natural gas and hydrogen with SMX mixing elements is developed to obtain homogeneous mixed gas injected into the natural gas pipeline network. The Reynolds-averaged Navier-Stokes (RANS) method is employed to investigate the flow physics in the static mixer, which was verified by experiments. The numerical results are in good agreement with the experimental data. Based on the static mixer model, the coupling relationship between mixing performance and the crucial parameters including the number of mixing elements, operating conditions and hydrogen blending volume fraction is analyzed in detail, and a compromise design scheme is proposed under the studied conditions to improve the mixing performance of natural gas and hydrogen. [Display omitted] • The mixing behavior of the natural gas and hydrogen mixing in a SMX static mixer is investigated. • The simulation results were compared and verified with the experimental data. • The internal coupling relationship between the flow loss and the crucial parameters is studied, and the flow physics inside the static mixer is clarified. • The compromise scheme and operation conditions of the static mixer design are obtained to improve the mixing performance of natural gas and hydrogen. [ABSTRACT FROM AUTHOR]

The mass transfer and mixing performance in the static mixers with three twisted leaves (TKSM) were investigated by the computational fluid dynamics coupled population balance model. A high-precision and efficient gas-liquid two phase model were evaluated by considering several drag models based on experimental bubble size distributions. The bubble size prediction matched well with experimental data and the mean relative error of Sauter mean diameter (d32) between the prediction and experiment values is 4.93 %. The drag correction factor considering hindering effect of small bubbles can improve the accuracy of cumulative probability distribution (CPD) prediction by 10.06 %. Bubble breakup capacity is quantized via gas-liquid interfacial area, and an empirical correlation between Eo and bubble aspect ratio (γ) have been proposed to predict morphological characteristics of bubble swarms. The effect of liquid Re on the mass transfer rate is much more significant than that of gas volume fraction (αd). The coefficients of variation profiles show that RL-TKSM has better mixing efficiency compared with LL-TKSM and perfect mixing could be achieved after seven mixing elements. The micro mixing efficiency of RL-TKSM is 1.06–1.14 times that of LL-TKSM, which indicates that RL-TKSM has excellent mixing and mass transfer performances. [ABSTRACT FROM AUTHOR]

In microbiology laboratories, it is essential to obtain high-quality samples where the culture media are completely homogeneous. The pour plate method includes having to melt the culture media—a mixture of agar and a nutrient solution—before seeding. A static mixer is designed for this purpose, employing CFD (Computational Fluid Dynamics) with the software OpenFOAM to simulate the fluid's behaviour in a helical static mixer with both internal and external configurations. The objective is to validate the CFD model by comparing it with the literature and provide a first approach to the mixer design. After satisfactory validation of the model, the results of the initial designs for Reynolds number 14 reveal the notably different behaviour of the fluids during mixing due to their differing properties, since agar and the nutrient solution present a high viscosity ratio. While the mixing efficiency is similar for the internal and external mixers, improved performance is demonstrated in the internal mixer, even for a shorter version. The external version of the mixer reaches a value for a mixing efficiency of 0.89 whereas the internal version performs more homogeneous mixing for the same number of mixing elements. This evaluation is based on a simplified internal design for computational simulations, whereas the external mixer is easier to manufacture but more complex to implement computationally. Finally, homogeneous mixing is achieved for the internal mixer configuration when adjusting its dimensions to those available on the market. [ABSTRACT FROM AUTHOR]

The hydrodynamic performance of turbulent flows in circular pipes equipped with screen-type static mixers is numerically assessed in this study. A three-dimensional computational fluid dynamics model is used to study the effect of changing the operating conditions and reactor configuration on the flow field. The accuracy of the numerical results is validated by comparing pressure drop predictions to empirical correlations where a maximum relative error of 13.3% is recorded. The macro-mixing performance of screen type static mixers is also assessed using residence time distributions. The study shows that the flow through screens is three-dimensional by nature with secondary flows being prominent near the pipe walls. Moreover, the presence of the screen has a major impact on the turbulent velocity profile both up- and down-stream. The flow field and velocity gradients are interpreted using strain rate and vorticity. These parameters also show that the flow through screens is highly dispersive where 39.3% of the reactor volume has an extensional efficiency value greater than 0.6. This explains their good performance in processing multiphase flows and gives an insight on how to design systems that maximize this dispersive effect in their volume. The residence time distribution study shows that the presence of screens renders the flow closer to plug flow with the effect being more pronounced using finer mesh screens operating at high flow velocities. [ABSTRACT FROM AUTHOR]

Co-current contacting of gas and liquid with a gas-continuous phase is a process with industrial relevance for natural gas processing, biogas upgrading, and carbon capture. Correlations that quantify two-phase, pressure losses under co-current flow conditions in corrugated geometries such as static mixers and structured packing at high gas-phase Reynolds numbers (R e G > 10 5 ) are currently lacking. To fill this void, two-phase pressure losses in corrugated plate geometries under co-current flow conditions were measured at: 3,000 < R e G < 320,000 and 9 < R e L < 590. Our previously developed single-phase pressure loss correlation is extended to predict the results from this multiphase scenario by utilizing the separated flow modeling framework where each phase contributes to the pressure loss in an independent manner. The previously developed single-phase correlation matches the measurements with an overall Mean-Absolute Percentage Error (MAPE) of 20% at high R e G compared to a MAPE of 24 – 109% obtained from previous literature correlations. The new proposed correlation, employing the critical gas Reynolds number for the onset of liquid entrainment, reduced the MAPE to 7% for R e G > 110,000 and 23% for R e G < 110,000 compared to the dataset. A preliminary Computational Fluid Dynamics analysis shows that a simple, reflecting droplet boundary condition provides an adequate representation of the interfacial pressure loss effects for the range of conditions investigated in this study. • Co-current two-phase flow in corrugated plate static mixers is studied. • Existing correlations do not match data well for co-current flow. • A new correlation based on the model of Lockhart & Martinelli is developed. • CFD discrete phase model predicts pressure loss well for lower liquid loading. [ABSTRACT FROM AUTHOR]

The ACHEMA 2022 was only half as large as usual, but the main trends in process technology were well represented. The research activities on the utilization of hydrogen and the use of CO2, CO and polymer waste as raw materials were highlights. Furthermore, new developments in the design of heat exchangers, mixers and reactors, the connection of digitalization and process engineering, new solutions for energy efficiency as well as sophisticated measuring techniques and demonstrations of safety engineering made the ACHEMA an exciting fair. [ABSTRACT FROM AUTHOR]

Copyright of Advanced Textile Technology is the property of Zhejiang Sci-Tech University Magazines and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Microfluidic formulation of liposomes has been extensively studied as a potential replacement for batch methods, which struggle with problems in scalability and difficulty in modulating conditions. Although microfluidic devices are considered to be able to combat these issues, an adequate replacement method has yet to be established.Methods: This paper examines the potential of a static mixer (SM) by comparing the encapsulation efficiency, loading, lamellarity, and user-friendliness with a commonly used microfluidic device, a staggered herringbone micromixer (SHM).Results: In both devices, it was found that as the initial lipid concentration increased, the particle size increased; however, the overall particle size was seen to be significantly larger in the liposomes prepared with SM. PDI remained significantly smaller in SM, however, signifying that better control of the particle size was accomplished in SM. In addition, the encapsulation efficiency was slightly smaller in SM compared to SHM, and in both devices, the values increased as the initial lipid concentration increased. The increase in encapsulation efficiencies was significantly smaller than that of the theoretical encapsulation efficiency, and this was found to be due to the increase in lamellarity as the initial lipid concentration increased.Discussion: In terms of user-friendliness, SM demonstrated significant advantages. The mixing elements could be taken out from the device, allowing for thorough cleaning of the element and device before and after experiments and ensuring experiments are conducted at virgin state in every round. Consequently, it was found that SM not only can produce uniformly distributed liposomes but has the potential to become a more practical method for liposome formulation with modifications in the mixing elements.

Abstract The effect of an in‐mold static mixer on orientation of fiber‐reinforced polypropylene (PP) was explored within the injection molding process. Several mold geometries and helical mixer designs were assessed via simulation to identify the mixing ability and the potential effect on fiber orientation. It was found that the static mixers within the runner segment could successfully mix the polymer and randomize the fibers but that the fiber alignment reduction was quickly recovered. Injection molding experiments were carried out to verify these simulations using one geometry case. Fiber orientation at different mold locations were measured using micro‐CT (μCT) scans and the degree of fiber orientation was quantified by “goodness of fit” to a normal Gaussian function approach. The experimental fiber orientation results showed good agreement with the simulations. These experiments indicated that the use of a static mixer within the runner system of a mold could be used for mixing the polymer melt after the plasticizing unit of the injection molding machine. However, its effect on changing the overall alignment of the fibers within injection molded parts could be offset by the melt flow downstream of the static mixer, suggesting the importance of mixer location with respect to the part cavity.

The production of liquid-gas mixtures with desired properties still places high demands on process technology and is usually realized in bubble columns. The physical calculation models used have individual dimensionless factors which, depending on the application, are only valid for small ranges consisting of flow velocity, nozzle geometry and test setup. An iterative but time-consuming design of such dispersion processes is used in industry for producing a liquid-gas mixture according to desired requirements. In the present investigation, we accelerate the necessary design loops by setting up a physical model, which consists of several subsystems that are enriched by dedicated experiments to realize liquid-gas dispersions with low volume fraction and small air bubble diameters in oil. Our approach allows the extraction of individual dimensionless factors from maps of the introduced subsystems. These maps allow for targeted corrective measures of a production process for keeping the quality. The calculation-based approach avoids the need for performing iterative design loops. Overall, this approach supports the controlled generation of liquid-gas mixtures. [Display omitted] • The production of desired liquid-gas mixtures places high demands on process technology. • Avoiding iterative design loops by setting up a physical model. • A dimensional analysis according to Buckingham's Pi Theorem identified. • An evaluation algorithm in which gas bubble sizes of different sizes and shapes are classified. • Calculate and measure the intermediate process points for model validation. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Complex geometries for electrodes are a great challenge in electrochemical applications. Slurry electrodes have been one example, which use complex flow distributors to improve the charge transfer between the current collector and the slurry particles. Here we use titanium‐based flow distributors produced by indirect 3D‐printing to improve further the electron transfer from highly conductive flow distributors to the slurry particles for a vanadium redox flow application. The titanium static mixers are directly coated with graphite to increase the activity for vanadium redox reactions. Increasing layers of graphite have shown an optimum for the positive and negative electrolytes. The application of heat treatment on the electrodes improves the anodic and cathodic current peaks drastically. Testing the highly conductive static mixers in a self‐made redox flow cell results in 110 mA cm−2 discharge polarization. [ABSTRACT FROM AUTHOR]

Static mixers could promote the particle mixing in industries. Experimental and numerical investigations of particle mixing and flow characteristics in the riser with static mixers are carried out. The instantaneous microscopic characteristics and energy loss in Kwerk-type static mixer (K-KSM) are evaluated by Computational Fluid Dynamics coupled with Discrete Element Method (CFD–DEM). A more suitable calculation method is proposed, which utilizes particle coordinates and the coordination number of central particles to calculate the instantaneous mixing degree of particles (P K). The P K , Residence Time Distribution (RTD) and collision correlation are analyzed at different superficial gas velocities (U g) and mass flow rates (M s). The results show that the performance of K-KSM is superior to that of KSM under current conditions. Back mixing and aggregation phenomena are eliminated at U g > 5 m/s and M s < 1.73 g/s, and the recommended regimes are U g ≥ 6.0 m/s and M s < 1.5 g/s. [Display omitted] • The particle characteristics inside a riser with the Kwerk elements are analyzed. • The images of discrete particles in a fluidized state are identified by CNNs. • The transient mixing correlation of two particles is evaluated. • A suitable method for calculating the mixing of discrete particles is proposed. [ABSTRACT FROM AUTHOR]