The Experts below are selected from a list of 2655 Experts worldwide ranked by ideXlab platform
Huali Wang - One of the best experts on this subject based on the ideXlab platform.
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achieving enhanced denitrification via Hydrocyclone treatment on mixed liquor recirculation in the anoxic aerobic process
Chemosphere, 2017Co-Authors: Yi Liu, Huali Wang, Xiurong CheAbstract:Abstract This work presents the novel application of Hydrocyclones for mixed liquor recirculation (MLR) treatment in the anoxic/aerobic (A/O) process to enhance the denitrification process. An exhaustive investigation on treated activated sludge and A/O effluents was conducted in batch and continuous operation tests. The median diameter of the sludge flocs was decreased from 78.82 μm to 15.77–23.31 μm, and the extracellular polymeric substances (EPS) desorption was observed, thus leading to the release of the soluble chemical oxygen demand (SCOD). A marked increase in the BOD 5 /TN ratio was consequently achieved, which supplied the carbon source and improved the biodegradability of the MLR. The Hydrocyclone treatment also enabled a 7.17% ± 0.93% specific oxygen utilization rate (SOUR) increase at the optimal Hydrocyclone intensity of 0.13 MPa, owing to the desorption of positioned microbial secretion from the microorganism cells. The nitrate reductase and nitrite reductase were also improved by 15.13% ± 1.16% and 17.61% ± 1.55%, respectively. The nitrate removal efficiency was enhanced by 13.6%, and the nitrogen oxide gases varied slightly; this behavior was consistent with the variations in the key enzymes involved in denitrification. The A/O process operated in the mode of Hydrocyclone-treated MLR, compared with in the conventional mode, resulted in a 15.56% higher TN removal, and the other effluent parameters remained stable. Hydrocyclone disruption is thus a convenient and energy-efficient process with broad implications in denitrification development.
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high speed particle rotation for coating oil removal by Hydrocyclone
Separation and Purification Technology, 2017Co-Authors: Yua Huang, Yanhong Zhang, Huali WangAbstract:Abstract Hydrocyclone not only achieves centrifugal separation of solids and liquids but also purifies oil-coated particles through rotational shear flow, resulting in high-speed particle rotation. This study develops a method to detect microsphere rotation assisted by microfluidic and high-speed imaging techniques. The developed method is applied to investigate the intensification mechanism of particle rotation on de-oiling oil-coated particles by using Hydrocyclone. Results show that the microspheres exhibit high rotation speed of more than 1000 rad/s when translating near the wall. The conical structure and inlet flow rate of Hydrocyclone significantly affect the magnitude and distribution of rotation speed in the equipment. An experiment on de-oiling real oil-coated spent catalysts verifies the de-oiling intensification of the Hydrocyclone, with the de-oiling efficiency being promoted by a minimum of 12.87% based on stirred hydrothermal tank. The de-oiling intensification mechanism is attributed to the strong resultant centrifugal force, whose direction periodically changes because of particle rotation and revolution. Overall, this study provides guidance for the design of washing Hydrocyclones for oil-coated particles.
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on the laboratory and field studies of removing fine particles suspended in wastewater using mini Hydrocyclone
Separation and Purification Technology, 2013Co-Authors: Qiang Yang, Huali WangAbstract:Abstract Developments in different industries are leading to increased fine particles in industrial wastewater. Fine particle grading, separation, and recycling involve many problems, and the separation quality is directly related to the economic benefits and environmental effects. In this study, a mini-Hydrocyclone with a nominal diameter of 25 mm was designed and tested for the separation of fine catalyst particles from water in the laboratory. The method was also used in the industrial methanol-to-olefin (MTO) quench water treatment process. Under certain feed conditions in the laboratory experiment, the separation efficiency of the mini-Hydrocyclone was around 88% and the particle cut size d 50 was 1.70 μm. The removal rate of particles larger than 3 μm reached ⩾85%. The two stages of the mini-Hydrocyclone separation process (i.e., clarification and concentrating) were examined, and the results showed that the process had high throughput and low loss. Recovery of MTO quench water by mini-hydroyclone and steam-stripping treatment were performed in an industrial plant. The cut size d 50 in the industrial application was 1.68 μm, which was close to that in the laboratory experiment. The stripping process removed ketone and methanol, which are poisonous and harmful components that prevent MTO quench water recovery. Furthermore, catalyst particles larger than 5 μm were almost completely recycled. The recovery process of MTO quench water by mini-hydroyclone and steam-stripping treatment was successful. These results demonstrated that mini-Hydrocyclone separation can be combined with other methods for the efficient treatment of industrial wastewater with fine particles.
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pressure drop and flow distribution in a mini Hydrocyclone group uu type parallel arrangement
Separation and Purification Technology, 2013Co-Authors: Cong Huang, Junye Wang, Jiangang Wang, Cong Che, Huali WangAbstract:Abstract Miniature Hydrocyclones have received increasing attention due to their advantages of improved separation precision, low cost, easy operation and high stability. However, because of small treatment capacity of a single mini-Hydrocyclone, numerous mini-Hydrocyclones need to be connected in parallel to meet capacity of treatment for industrial applications. Thus, optimal method of parallel design of the numerous mini-Hydrocyclones becomes a major challenge. In this paper, a general mathematical model was developed for a UU-type parallel mini-Hydrocyclone group. Detailed analytical solutions were obtained to predict the pressure drop and flow distribution under different flow conditions and geometrical structures. Furthermore, an experimental apparatus with 12 HL/S25-type mini-Hydrocyclones parallel in the UU-type arrangement was set up to verify the model under different inlet pressures. The results showed that the inlet pressure could be used to adjust uniformity of flow distribution. It was found that the theoretical pressure drop and flow distribution were in good agreement with the experimental data at 0.10 MPa. The percentage of relative error was within 8% and less than 5% for pressure drop distribution and for flow distribution, respectively. The present model also studied the influence of the split ratio on pressure drop and flow distribution since there were two exhaust headers. The uniformity of these distributions increased as the split ratio increased. The present methodology and results provide a simple yet powerful analysis that could assist in the design and optimization of new mini-Hydrocyclone systems for industrial applications and commercialization.
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cfd study on separation enhancement of mini Hydrocyclone by particulate arrangement
Separation and Purification Technology, 2013Co-Authors: Qiang Yang, Huali WangAbstract:Abstract Several mini-Hydrocyclones are designed to improve fine particle separation using computational fluid dynamics. This article based on the idea of particle arrangements at the entrance of a Hydrocyclone, designed a common mini-Hydrocyclone (CM-Hydrocyclone), positive rotation mini-Hydrocyclone (PRM-Hydrocyclone), with particle size increasing from the inside to the wall at the entrance, and a reverse rotation mini-Hydrocyclone (RRM-Hydrocyclone), which with an opposite-particle arrangement. The particles’ arrangement and separation-strengthening mechanism are studied with FLUENT software. The governing equations are coupled using the SIMPLE algorithm, while the Reynolds Stress Model is employed for the Hydrocyclone turbulent model due to its anisotropic nature. Particle trajectories are simulated based on a Lagrangian frame considering continuous phase interactions. The results show that the particles closer to the outer wall or to the lower part of the entrance tend to be separated with the underflow. The particles injected from upside of the inlet tend to be trapped in the under-cover flow with a long path and get discharged with the shortcut flow. The main separation zone for the mini-Hydrocyclone located in the region between the vortex finder tip and the upper quarter of the cone. Particle arrangements at the entrance of Hydrocyclone have a significant impact on separation efficiency of fine particles. RRM-Hydrocyclone with particle size that increases from the wall to the inside of the entrance can improve separation efficiency. RRM-Hydrocyclone demonstrated 83% separation efficiency when the average particle size is 0.53 μm. This is much higher than the values demonstrated by CM-Hydrocyclone and PRM-Hydrocyclone. However, PRM-Hydrocyclone, with particle size that decreases from the wall to the inside of the entrance, can eliminate short circuit flow.
Hualin Wang - One of the best experts on this subject based on the ideXlab platform.
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experimental study of mini Hydrocyclones with different vortex finder depths using particle imaging velocimetry
Separation and Purification Technology, 2020Co-Authors: Jianggang Wang, Shaofan Li, Hualin Wang, Fengqin He, Xiao XuAbstract:Abstract Characterization of flow field inside the Hydrocyclone is helpful in optimizing Hydrocyclone structure design. In this work, flow patterns in a mini-Hydrocyclone with various vortex finder depths were studied with Particle Image Velocimetry (PIV). Axial velocity and radial velocity distributions of the central plane orthogonal to the inlet of mini-Hydrocyclone were acquired, streamline diagrams were constructed from the measured vectors, and calculated from the experimental data. An analysis of the experimental data shows that the structural parameters of Hydrocyclones have a critical impact on the flow field structure, and the experiment operation conditions only have an influence on strength of the flow fields. Vortex finder depth has a significant influence on the volume of the main separation zone and separation performance of mini-Hydrocyclone. The optimal depth of the vortex finder was found to be a ratio of vortex finder depth to mini-Hydrocyclone cylindrical section diameter L0/D of 1.0.
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pressure drop and flow distribution in a group of parallel Hydrocyclones z z type arrangement
Separation and Purification Technology, 2013Co-Authors: Junye Wang, Hualin Wang, Cong Chen, Cong HuangAbstract:Abstract The mini-Hydrocyclone has received increasing attention due to its clear advantages of high efficiency, separating precision and relatively low cost. However, its handling capacity decreases as the nominal diameter of a Hydrocyclone decreases. Therefore, a group of mini-Hydrocyclones are often employed to meet industrial handling capacity which imposes the difficulty of prediction, analysis, and design of such a group of the mini-Hydrocyclone system. There is no theoretical model to evaluate design and operation of the system. The objective of this paper is to develop a general theoretical model to evaluate the flow distribution and the pressure drop in parallel mini-Hydrocyclone groups with Z-Z-type arrangement. Detailed analytical solutions were obtained so that they can be easily used to predict the pressure drop and flow distribution under the different flow conditions and geometrical parameters. Furthermore, an experimental apparatus with 12 HL/S25-type mini-Hydrocyclones parallel in the Z-Z-type arrangement was set up to verify the model under different inlet pressures. It was found that the theoretical pressure drop and flow distribution were in good agreement with the experimental data. Meanwhile, with the combination of the different theoretical calculation cases, the percentage of relative error will be controlled within 1%. The present model also studied the influence of the split ratio on pressure drop and flow distribution since there were two exhaust headers. The uniformity of these distributions increased as the split ratio increased. This paper provided an easy-to-use design guidance to investigate the interactions among structures, operating conditions and manufacturing tolerance, in order to improve the performance of a parallel mini-Hydrocyclone separator group.
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the coordinated relationship between vortex finder parameters and performance of Hydrocyclones for separating light dispersed phase
Separation and Purification Technology, 2011Co-Authors: Qiang Yang, Hualin Wang, Jiangang Wang, Zhiming LiAbstract:Abstract Hydrocyclones for separating light dispersed phase are applicable to various processes in the separation of light dispersion. The relationship of the structure parameters and flow field is in the frontier of the research and not clear so far. In this paper, Phase Doppler Particle Analyzer (PDPA) was used for the first time to systematically study the influence of the change of structure and size of vortex finder on the zero axial velocity wave zone (ZAVWZ), the tangential velocity gradient, the centrifugal separation factor and the size distribution of dispersed phase. The Hydrocyclone was designed with diameter of Φ 35 mm, hollow glass beads ( d 50 = 30.61 μm, ρ = 0.82 g/cm 3 ) were used as the dispersed phase and water was used as the continuous phase. The test results were used as the evaluation index to optimize the depth of vortex finder at 0.143 L s and its diameter at 0.071 D . The performance of the Hydrocyclone was also examined under the same material and flow condition as the PDPA test for flow field, which showed the separation performance of the optimized Hydrocyclone reached up to 92.3%, while the inlet flow rate was 1.5 m 3 /h and the split ratio was 8%. At last, the reliability for taking the test results, the length of zero axial velocity wave zone (ZAVWZ), the centrifugal separation factor and the tangential velocity gradient as the evaluation index were also verified.
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solid liquid separation performance of Hydrocyclones with different cone combinations
Separation and Purification Technology, 2010Co-Authors: Qiang Yang, Hualin Wang, Zhiming LiAbstract:Abstract Hydrocyclones used for solid–liquid separation are usually composed of a single cone. In this paper, we designed Hydrocyclones with two cone combinations for solid–liquid separation and studied the flow field and separation performance. Simulation and experimental results showed that when the second cone remained unchanged, the angle change of the first cone had significant effect on the value of three-dimensional velocities, flow split, separation efficiency, energy consumption, and separation sharpness, but little effect on the distribution of pressure and that of three dimensional velocities, the capacity and cut size. The bigger of the first cone's angle, the smaller of the flow split and the higher the separation efficiency, the stronger of the centrifugal force, and the more the small particles in underflow. The smaller the angle change between the two cones, the larger the sharpness of the grade efficiency curve, i.e., the Hydrocyclone is more suitable for the classification process.
Fengqin He - One of the best experts on this subject based on the ideXlab platform.
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experimental study of mini Hydrocyclones with different vortex finder depths using particle imaging velocimetry
Separation and Purification Technology, 2020Co-Authors: Jianggang Wang, Shaofan Li, Hualin Wang, Fengqin He, Xiao XuAbstract:Abstract Characterization of flow field inside the Hydrocyclone is helpful in optimizing Hydrocyclone structure design. In this work, flow patterns in a mini-Hydrocyclone with various vortex finder depths were studied with Particle Image Velocimetry (PIV). Axial velocity and radial velocity distributions of the central plane orthogonal to the inlet of mini-Hydrocyclone were acquired, streamline diagrams were constructed from the measured vectors, and calculated from the experimental data. An analysis of the experimental data shows that the structural parameters of Hydrocyclones have a critical impact on the flow field structure, and the experiment operation conditions only have an influence on strength of the flow fields. Vortex finder depth has a significant influence on the volume of the main separation zone and separation performance of mini-Hydrocyclone. The optimal depth of the vortex finder was found to be a ratio of vortex finder depth to mini-Hydrocyclone cylindrical section diameter L0/D of 1.0.
Qiang Yang - One of the best experts on this subject based on the ideXlab platform.
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on the laboratory and field studies of removing fine particles suspended in wastewater using mini Hydrocyclone
Separation and Purification Technology, 2013Co-Authors: Qiang Yang, Huali WangAbstract:Abstract Developments in different industries are leading to increased fine particles in industrial wastewater. Fine particle grading, separation, and recycling involve many problems, and the separation quality is directly related to the economic benefits and environmental effects. In this study, a mini-Hydrocyclone with a nominal diameter of 25 mm was designed and tested for the separation of fine catalyst particles from water in the laboratory. The method was also used in the industrial methanol-to-olefin (MTO) quench water treatment process. Under certain feed conditions in the laboratory experiment, the separation efficiency of the mini-Hydrocyclone was around 88% and the particle cut size d 50 was 1.70 μm. The removal rate of particles larger than 3 μm reached ⩾85%. The two stages of the mini-Hydrocyclone separation process (i.e., clarification and concentrating) were examined, and the results showed that the process had high throughput and low loss. Recovery of MTO quench water by mini-hydroyclone and steam-stripping treatment were performed in an industrial plant. The cut size d 50 in the industrial application was 1.68 μm, which was close to that in the laboratory experiment. The stripping process removed ketone and methanol, which are poisonous and harmful components that prevent MTO quench water recovery. Furthermore, catalyst particles larger than 5 μm were almost completely recycled. The recovery process of MTO quench water by mini-hydroyclone and steam-stripping treatment was successful. These results demonstrated that mini-Hydrocyclone separation can be combined with other methods for the efficient treatment of industrial wastewater with fine particles.
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cfd study on separation enhancement of mini Hydrocyclone by particulate arrangement
Separation and Purification Technology, 2013Co-Authors: Qiang Yang, Huali WangAbstract:Abstract Several mini-Hydrocyclones are designed to improve fine particle separation using computational fluid dynamics. This article based on the idea of particle arrangements at the entrance of a Hydrocyclone, designed a common mini-Hydrocyclone (CM-Hydrocyclone), positive rotation mini-Hydrocyclone (PRM-Hydrocyclone), with particle size increasing from the inside to the wall at the entrance, and a reverse rotation mini-Hydrocyclone (RRM-Hydrocyclone), which with an opposite-particle arrangement. The particles’ arrangement and separation-strengthening mechanism are studied with FLUENT software. The governing equations are coupled using the SIMPLE algorithm, while the Reynolds Stress Model is employed for the Hydrocyclone turbulent model due to its anisotropic nature. Particle trajectories are simulated based on a Lagrangian frame considering continuous phase interactions. The results show that the particles closer to the outer wall or to the lower part of the entrance tend to be separated with the underflow. The particles injected from upside of the inlet tend to be trapped in the under-cover flow with a long path and get discharged with the shortcut flow. The main separation zone for the mini-Hydrocyclone located in the region between the vortex finder tip and the upper quarter of the cone. Particle arrangements at the entrance of Hydrocyclone have a significant impact on separation efficiency of fine particles. RRM-Hydrocyclone with particle size that increases from the wall to the inside of the entrance can improve separation efficiency. RRM-Hydrocyclone demonstrated 83% separation efficiency when the average particle size is 0.53 μm. This is much higher than the values demonstrated by CM-Hydrocyclone and PRM-Hydrocyclone. However, PRM-Hydrocyclone, with particle size that decreases from the wall to the inside of the entrance, can eliminate short circuit flow.
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the coordinated relationship between vortex finder parameters and performance of Hydrocyclones for separating light dispersed phase
Separation and Purification Technology, 2011Co-Authors: Qiang Yang, Hualin Wang, Jiangang Wang, Zhiming LiAbstract:Abstract Hydrocyclones for separating light dispersed phase are applicable to various processes in the separation of light dispersion. The relationship of the structure parameters and flow field is in the frontier of the research and not clear so far. In this paper, Phase Doppler Particle Analyzer (PDPA) was used for the first time to systematically study the influence of the change of structure and size of vortex finder on the zero axial velocity wave zone (ZAVWZ), the tangential velocity gradient, the centrifugal separation factor and the size distribution of dispersed phase. The Hydrocyclone was designed with diameter of Φ 35 mm, hollow glass beads ( d 50 = 30.61 μm, ρ = 0.82 g/cm 3 ) were used as the dispersed phase and water was used as the continuous phase. The test results were used as the evaluation index to optimize the depth of vortex finder at 0.143 L s and its diameter at 0.071 D . The performance of the Hydrocyclone was also examined under the same material and flow condition as the PDPA test for flow field, which showed the separation performance of the optimized Hydrocyclone reached up to 92.3%, while the inlet flow rate was 1.5 m 3 /h and the split ratio was 8%. At last, the reliability for taking the test results, the length of zero axial velocity wave zone (ZAVWZ), the centrifugal separation factor and the tangential velocity gradient as the evaluation index were also verified.
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solid liquid separation performance of Hydrocyclones with different cone combinations
Separation and Purification Technology, 2010Co-Authors: Qiang Yang, Hualin Wang, Zhiming LiAbstract:Abstract Hydrocyclones used for solid–liquid separation are usually composed of a single cone. In this paper, we designed Hydrocyclones with two cone combinations for solid–liquid separation and studied the flow field and separation performance. Simulation and experimental results showed that when the second cone remained unchanged, the angle change of the first cone had significant effect on the value of three-dimensional velocities, flow split, separation efficiency, energy consumption, and separation sharpness, but little effect on the distribution of pressure and that of three dimensional velocities, the capacity and cut size. The bigger of the first cone's angle, the smaller of the flow split and the higher the separation efficiency, the stronger of the centrifugal force, and the more the small particles in underflow. The smaller the angle change between the two cones, the larger the sharpness of the grade efficiency curve, i.e., the Hydrocyclone is more suitable for the classification process.
Chao Shen - One of the best experts on this subject based on the ideXlab platform.
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experimental study on liquid flow fields in de foulant Hydrocyclones with reflux ejector using particle image velocimetry
Separation and Purification Technology, 2020Co-Authors: Jinyi Tian, Long Ni, Chao Shen, Tao SongAbstract:Abstract Hydrocyclone has been extensively used in various separation processes. For example, in the sewage source heat pump system, a De-Foulant Hydrocyclone with Reflux Ejector (DFHRE) can fully use the kinetic energy of its overflow to suck its underflow and flush away the foulants flowing out with the underflow. Our previous experiments in 2018 showed that the reflux ejector could prevent the underflow orifice from blocking, and reducing the suction angle could increase the separation efficiency by approximately 10% whereas decreasing its energy consumption markedly. To date, however, its mechanism is still unclear. Therefore, in this study, we used the Particle Image Velocimetry (PIV) method to study the flow field in DFHREs with different suction angles and compared it with that in the traditional Hydrocyclone without reflux ejector. Results indicated that, in all the tested DFHREs, there was a negative-axial-velocity area in the center of Hydrocyclones, which was not found in the center of the tested traditional Hydrocyclone. The negative axial velocity produced by the overflow-suck-underflow decreased with increasing suction angle whereas increased with increasing inlet velocity. The split ratio and total pressure drop of the DFHRE are respectively and approximately 18.5% and 28.3kPa greater than those of the traditional Hydrocyclones at the suction angle of 30°. This proved that the experimental performance of the sewage suction ejector used in Hydrocyclone, that is, the suction effect of the reflux ejector and the separation efficiency of DFHRE were the best at the suction angle of 30°. Besides, the obtained change of flow field caused by the reflux ejector provided a new idea for enhancing Hydrocyclone separation.