Average Separation Efficiency Research Articles

Numerical study of influencing geometry of separator elements for cleaning dust of food production on its efficiency

At modern food enterprises, the task of providing high-quality air cleaning from dust is relevant. The paper proposes an original dust separator, the peculiarity of which is the presence of structural elements of different shapes, arranged in a chess order. This design solution ensures the formation of a wave-like structure of the gas-dust flow within the device. The separation of solids from air is due to inertial and centrifugal forces. The aim of the work is to evaluate the fractional efficiency of this separator with structural elements of different geometric shape during the dust capture process. The paper considers I-shaped, P-shaped, arc-shaped and V-shaped structural elements. The study is carried out by numerical simulation at a gas dust flow rate of 0.5 to 3 m/s and a particle size of 10 to 200 ?m. During the work it has been found that the shape of the structural elements largely determines the efficiency of separation of dust material from the gas stream. The V-shaped design elements have shown the highest average separation efficiency compared to other shapes under other equal conditions. This is due to the fact that in such a separator the particles are directed to their apex, where the velocity of the particles decreases contributing to their subsequent settling into the bunker. The maximum efficiency for V-shaped elements is on average 80.1 % at a gas dust inlet velocity of 0.5 m/s. The lowest efficiency is observed for I-shaped elements, as particles return to the air stream after rebounding from the walls.

Effect of Different Outlet Structure of Axial Flow Cyclone Separator in Drying Tower

The axial flow cyclone separator used in drying tower is characterized by the diameter of the dust outlet at the tail is larger than that of the cylinder, and the dust removal efficiency is increased by a series dust outlet. The numerical analysis of its separation characteristics is carried out by using the RSM model of CFD. The results show that the separation efficiency can be increased by appropriately increasing the diameter of the dust outlet, and the separation efficiency will not change when the diameter of the dust outlet increases to a certain value. When the insertion depth of the air outlet is reduced from 150mm to 100mm, the average separation efficiency of particles with a diameter of 15-30um is reduced by 4.5%. When the insertion depth of the air outlet is greater than the width of the dust outlet, the insertion depth has no effect on the dust removal efficiency. The tandem dust outlet and parallel dust outlet have the same separation effect on small particles, and the gas flow rate is equivalent to twice the gas flow rate of a single dust outlet. The average particle separation efficiency of 1 - 30um is increased by 16.5% compared with that of a single dust outlet. The flow velocity of the tandem dust outlet is higher than that of the parallel dust outlet.

Minimum Minutes Machine-Learning Microfluidic Microbe Monitoring Method (M7).

Frequent outbreaks of viral diseases have brought substantial negative impacts on society and the economy, and they are very difficult to detect, as the concentration of viral aerosols in the air is low and the composition is complex. The traditional detection method is manually collection and re-detection, being cumbersome and time-consuming. Here we propose a virus aerosol detection method based on microfluidic inertial separation and spectroscopic analysis technology to rapidly and accurately detect aerosol particles in the air. The microfluidic chip is designed based on the principles of inertial separation and laminar flow characteristics, resulting in an average separation efficiency of 95.99% for 2 μm particles. We build a microfluidic chip composite spectrometer detection platform to capture the spectral information on aerosol particles dynamically. By employing machine-learning techniques, we can accurately classify different types of aerosol particles. The entire experiment took less than 30 min as compared with hours by PCR detection. Furthermore, our model achieves an accuracy of 97.87% in identifying virus aerosols, which is comparable to the results obtained from PCR detection.

Design Methodology for a Low-Shear Rotating Swirler

The tubular dynamic hydrocyclone (TDH) holds great potential for the pre-deoiling of offshore oil platforms. However, the shear and turbulence in the flow field can cause the oil droplets, the dispersed phase in water, to break up when the swirling flow is produced by the swirler. A design method is proposed for the low-shear rotary swirler (LSRS) of TDH, the aim of which is to reduce the shear force and local turbulence during the fluid forming swirling flow. The blade setting angle of the LSRS is calculated based on the relative velocity vector between the fluid and the swirler. The distribution characteristics of the tangential velocity and turbulence in the TDH with LSRS are simulated by Computational Fluid Dynamics (CFD). The maximum stable droplet diameter is analyzed. The results show that the shear stress and turbulence energy dissipation rates are reduced by 74.6% and 68.5%, respectively, and that the stable droplet diameter is increased by more than 60%, compared to the conventional rotating swirler. In addition, a TDH prototype with LSRS was tested in an offshore oil field by continuous operation for more than 36 h. The average separation efficiency was 83%, and the average underflow oil concentration was 27 mg/L. The research also found that the drastic changes in the tangential velocity along the axial direction were critical to shear. Moreover, the results make up for the deficiency of the spatial variation of the tangential velocity in the dynamic cyclone separator.

Particle combination characteristics on PM2.5 granular bed filtration efficiency and pressure drop

Granular bed filters are widely utilized in hot gas dust removal due to their low cost, high temperature resistance, and simple structure compared with other dust removal methods. Conventional granular bed filtration is usually only applicable to the separation of particulate matters above PM10, and its PM2.5 efficiency separation needs to be improved. A new method for efficiently separating PM2.5 is developed in this study by combining different filter media. The effects of filter deck thickness, filter mediums diameter, and granular bed combination characteristics on PM2.5 separation efficiency and separation pressure drop are systematically studied. A group of single-deck filtration experiments show that the average separation efficiency for PM2.5 can reach 92.9% with an average separation pressure drop of 0.53 kPa. Double-deck granular bed filtration can also offer an average separation efficiency for PM2.5 91.2%, but the average separation pressure drop is significantly reduced to 0.4 kPa. The results prove that compared with a single granular bed; double granular beds demonstrate evident advantages in energy consumption ratio. This study provides references for studying PM2.5 in depth separation and granular bed filtration.

Internal reuse of methanol-to-olefin wastewater based on micro-channel separation coupling hydrocyclone regeneration

Methanol-to-olefin (MTO) is a typical new coal chemical industry example. Due to the large volume of generated wastewater, complex composition including catalysts, aromatics and various oxygen-containing compounds, and serious environmental hazard, wastewater recycling is critical for sustainable industrial development and ecological protection. Herein, a swirl regenerating micro-channel separation (SRMS) technology was proposed to integrate deep filtration and hydrocyclone-enhanced regeneration. A small-scale experimental investigation was first conducted to verify the feasibility of the MTO wastewater treatment. A pilot SRMS device with a treatment capacity of 20 m3/h was constructed, and the device's continuous operation effect and stability were comprehensively evaluated. The separation performance of the SRMS device at different solution pH values and the impact of the hydrocyclone-enhanced regeneration of separation media were discussed in detail. At low solution pH values (<7), the SRMS device exhibits an average separation efficiency of 92.0% for fine particulate matter in wastewater, and the median particle size, d50, decreases from 1.55 to 0.6 μm. As the solution pH increases, the repulsive energy barrier for the medium-contaminant and contaminant-contaminant increases, inhibiting the deposition behavior of particulate pollutants. In addition, hydrocyclone desorbs contaminants deposited on the separation media and the average contaminant residual rate decreases from 3.3 to 0.2 wt%. We propose an industrial application for treating and reusing MTO wastewater (200 m3/h) using the SRMS technology based on the experimental results. The costs of the wastewater treatment process are as low as 0.25 CNY/m3, and the wastewater reuse rate is over 97% without chemical consumption. This work can provide an environmentally friendly and economically sustainable approach to the source management of MTO wastewater.

Photoswitchable and reusable superhydrophobic/hydrophilic TiO2-coated stainless-steel mesh as oil–water separator

This study fabricated a superhydrophobic/hydrophilic stainless-steel mesh with a TiO2-coated surface for efficient oil–water separation. The mesh manifested both hydrophobic and hydrophilic properties upon incorporating fluorine- and amine-containing silanes, respectively. The photoswitching speed and recovery of surface properties were evaluated by adjusting the UV irradiation period. Additionally, the mesh was subjected to ultrasonic treatment to enhance the photoswitching speed. After alternating UV irradiation and ultrasonification treatments, the variations in contact angle confirmed the feasibility of reversible surface conversion: 158° → 15° → 149.4° → 9.1° → 146.8° → 8.4° → 147.3°. Furthermore, the oil–water separation efficiency of the fluorine-modified mesh was assessed using water and n-hexane solutions. Over eight cycles, the hydrophobic/hydrophilic mesh achieved an average separation efficiency of 95.3% and 96.7%, respectively. The separation process occurred within approximately 5 s. Thus, this study proposed a comprehensive approach for developing a single superhydrophobic mesh capable of facile and rapid photoswitching between hydrophilic and hydrophobic properties. The developed mesh offers precise filtration, durability, and reusability, contributing to sustainable oil–water separation processes.

132 Evaluation of the Effectiveness of a New Technical Solution to Reduce Dust Emission from Road Planers

Abstract A planer equipped with a rotating cutting drum is used to remove about ten cm thick of road surfaces. This process generates dust likely to contain crystalline silica. The machine operator and people around may be particularly exposed. It is therefore essential to promote effective preventive solutions, in particular from dust collection and filtration systems, to reduce dust exposure. Tests were realized to evaluate the performance of technical devices designed to capture and filter dust emitted by road planers. The measurements were carried out on a road planer equipped with an air collection device located next to the milling drum, supplemented by an electrostatic separator to trap collected dust. The dust collection efficiency of the venting system was determined by gas tracing. The efficiency of the electrostatic separator was both evaluated in laboratory conditions (static machine) from a reference dust generated upstream of the system, and in the field during road surface planing. The tests conducted on the planer showed the effectiveness of the dust collection and filtration devices implanted on the machine and tested both in static and in the field. The capture efficiency determined by gas tracing is about 90 % and the separation efficiency of the electrostatic precipitator, determined on the static machine from test dust, is respectively 60 and 90% at aerodynamic diameters 1 and 4 μm. The average separation efficiency obtained from the measurements with the machine in real operation is 91% for respirable dust and 95% for respirable crystalline silica.

Determination of Separation Efficiency of Hydrocyclone Used Pre-Filter in Micro Irrigation at Different Inlet Velocities and Sand Diameters

Hydrocyclones are used as pre-filter to reduce suspended particles in irrigation water on the subsequent filters. The aim of the study was to determine separation efficiency (SE) of hydrocyclones, called H1, H2 and H3 according to inlet/outlet diameters, at water velocities of 1.0 (V10), 1.5 (V15) and 2.0 (V20) ms-1, and sands diameter of 0.5 (D05), 1.0 (D10), 1.5 (D15), 2.0 (D20) and 2.5 (D25) mm. Therefore, a hydrocyclone laboratory test system was constituted using a water tank, motor pump, inverter, flowmeter, valve, hydrocyclone, disk filter, and polythene pipe. Separation efficiencies were calculated by dividing amounts of sand collected in collection box by feeding amount of sand. The lowest average separation efficiency was determined as 37% at H1V10D05 treatment and the highest ones as 97% at both H2V20D10 and H3V20D20, and the other ones changed between two values. Average separation efficiencies resulted as 69%, 88% and 88% for H1, H2 and H3 hydrocyclones, and 71%, 84% and 90% for V10, V15 and V20 water velocities, and 78%, 82%, 82%, 83% and 84% for D05, D10, D15, D20 and D25 sand diameters, respectively. Besides these, average separation efficiency for three parameters was 82%. Since the inlet size of H2 is smaller than that of H3 and its SE was higher than that of H1 and equal to that of H3, the most suitable hydrocyclone was determined as H2 to be used in the micro irrigation. The highest average separation efficiency was 90% at a water velocity of 2.0 ms-1. According to separation efficiency of the hydrocyclone, the optimum water velocity in the inlet of the hydrocyclone was determined as 2.0 ms-1. The separation efficiency of hydrocyclone showed that the efficiencies increased with increasing water velocity from 0.5 ms-1 to 2.0 ms-1 and sand diameters from 0.5 to 2.5 mm. In separation efficiency for micro irrigation, water velocities and suspended materials play crucial roles as well as hydrocyclone mechanical properties.

Numerical Simulation of an Oil Mist Particle Emission and Gas-Oil Separation Device of a Closed Machine Tool in the Post-Environmental Area.

Owing to the airflow field within airtight machines, oil mist particles escape with the airflow from the machine shell gaps and are emitted externally to the post-environmental area, causing air pollution and threatening workers' health. The existing local exhaust system is ineffective in capturing oil mist particles. This study proposes a gas-oil separation device that can "in-situ control" the oil mist particles in situ and weaken their outgoing emission and that uses numerical simulations to compare and analyse the emission characteristics of oil mist particles, before and after the addition of the separation device at different exhaust air volumes and particle emission speeds, and to design the structural parameters of the device to improve the separation efficiency of oil mist particles. The structural parameters of the proposed device are designed to improve the separation efficiency of oil mist particles. Studies have shown that for every 200 m3/h increase in exhaust air volume, the capture efficiency increases by around 3%, and the particle concentration at the gap in the machine loading door decreases from 9.4 × 10-7 kg/m3 to 7.7 × 10-7 kg/m3. The overall escape rate of oil mist particles is in the range of 10-13% after the addition of a pressure relief device. Numerical simulations are performed to analyse the effects of inlet airflow velocity, folding plate spacing, and folding plate angle on the separation efficiency of oil mist particles. Results show that an increase in the inlet velocity of the airflow increases the particle separation efficiency. The most suitable structural parameters for the separation device and the machine are as follows: 60° angle of the folding plate and 30 mm distance between plates, where the separation efficiency is above 80%, and the average separation efficiency is about 86%. The results of this study can be used as a reference for the study of the emission of oil mist particles from enclosed mechanical cutting machines.

Preparation and research of Mn-TiO2/ Fe membrane with high efficiency light-oil/water emulsion separation

To control the water pollution caused by industrial oily wastewater, scientific research in the field of oil-water separation has begun all over the world, which has also attracted extensive attention to green advanced separation materials. Herein, we used stainless steel mesh as one of the reactants to load metal oxide particles formed by tetrabutyl titanate (TBT), and manganese acetate on cotton mesh under acidic conditions to prepare a membrane material with excellent oil-water separation. The results showed that the 0.1/0.3/0.5 Mn-TiO2/Fe membranes prepared by high-temperature hydrothermal reaction had an excellent separation effect in the light oil and water separation after 10 cycles, and its maximum oil-water separation efficiency was 89.87%, 92.65% and 96.96% respectively. At the same time, the membrane still had good hydrophobicity after acid, alkali and high temperature and low-temperature treatment. In the light oil and water separation experiment measured after 15 times of friction with sandpaper, the 0.5Mn-TiO2/Fe membrane showed good durability, and the average separation efficiency was 93.82% respectively. This diversified wettability and separation process of stainless steel mesh load on the membrane surface has a wide range of potential applications in environmental protection, energy utilization, industrial manufacturing and so on.

Separation of fine waste catalyst particles from methanol-to-olefin quench water via swirl regenerating micro-channel separation (SRMS): A pilot-scale study

From the perspective of resource reserves, the development of coal-based methanol-to-olefins (MTO) technology is regarded as an important direction for the sustainable development of the chemical processing industry in China. However, the wastewater generated in the process of industrial operation has a significant impact on the stability of the process. To remove the fine waste catalyst particles from MTO quench water, a swirl regenerating micro-channel separation (SRMS) technology was developed. A 25 m3/h pilot-scale study was conducted to examine the separation and regeneration effects under different operating parameters and verify the feasibility of this technology through a long-duration experiment. Results showed that for filtration velocities ranging from 11 to 15 m/h, the total separation efficiency was 95–99 %, the removal efficiency of 0.2 μm particles was 83–90 %, and the regeneration cycle was 24–40 h while the waste catalyst particle concentration in quench water was 300–600 mg/L. The optimum regeneration water and gas speeds were determined to be 11–15 m/h and 56.6 m/h, respectively. Moreover, the performance of the pilot plant over 600 h continuous operation effect of was tested, and an average separation efficiency > 95 % with excellent regeneration was obtained.

The effect of fluctuating boundary on flow field and performance parameters of cyclone separator

In this study, fluctuation with three frequencies is applied to the boundaries of the cyclone separator. Flow field including dominant frequency and amplitude of vortices at three regions (vortex finder, main cylinder, and cone) and performance parameters (collection efficiency and pressure drop) are studied. Lagrangian-Eulerian Frame is applied, and Large Eddy Simulation (LES) is used for turbulence modeling. Three inlet flows of 4, 6, and 8 [g/s] are considered. The Power Spectral Density (PSD) of fluctuations has been increased by increasing the inlet flow rate. The fluctuating flow will make vortices with higher amplitude than the uniform flow. Because the high amplitude vortex breaks into and transmits energy to the small vortex, pressure drop increases with frequency increment. The pressure drop equations in the non-uniform flow of the cyclone are derived based on the existing pressure drop relationships. The average separation efficiency in non-uniform flow is less than uniform flow.

Purification of black alkali liquor by microchannel filtration to promote energy savings and consumption reduction in lye cleaning systems

Traditionally, multistage plate-frame filtration or centrifugal treatment methods are used to remove fiber from black alkali liquor with high viscosity and high fiber impurity content. However, these methods are limited by the long processes and high consumption of energy and materials. Therefore, in this paper, a new microchannel (deep) filtration process and device were proposed and used to replace the original “three-step” separation process (i.e., metal plate-frame filtration, first-stage polypropylene filtration and second-stage polypropylene filtration) and device. Separation media with different particle sizes were used to carry out online separation experiments. Results showed that an effective separation could be realized by using the combined multiparticle media with a length-diameter ratio of <30. Specifically, the average separation efficiency was higher than 90%. The workload was reduced by 66%. The floor area was decreased by 52%. The energy consumption was reduced by 64%. The material consumption was nearly zero. It is hoped that this study can not only benefit energy savings and cleaner production in the viscose fiber industry but also serve as a useful guide for other chemical industries.

Optimizing the structural parameters of downhole vortex tool in gas well using a genetic algorithm

Structural parameters of vortex tools affect the drainage of water producing gas wells, while previous research mostly focused on the optimization of individual parameters. This study aimed at establishing the optimal sizes of downhole vortex tools. The gas-liquid separation efficiency (SE) model and pressure loss model of the vortex tool were also established. A multi-objective genetic algorithm (GA) optimization process was designed to achieve the maximum SE and minimum pressure loss of the vortex tool. A sensitivity analysis was performed to investigate the impact of structural parameters on SE and pressure loss of vortex tools. It was found that an increase in the spindle diameter (DVT) and/or the helical height (HVT) and/or a decrease of the flow channel width (WFC) improved the SE of the vortex tool. In addition, reducing DVT and/or HVT and/or increasing WFC reduced the pressure loss of the vortex tool. A set of optimum combinations of structural parameters was obtained through GA with an average SE of 0.9982, an average pressure loss of 1513.3 Pa, and an average fitness function value of 0.0068. Field results showed that the optimized vortex tools were conducive for gas well drainage and improved gas production. An optimized method for designing the structural parameters in vortex tools has been proposed in this study. Our study findings are of great significance in improving the drainage capacity of water producing gas wells.

Forming and stripping of the wall film and the influence on gas–liquid separation

AbstractThe paper aims to investigate re‐entrainment mechanisms of wall films. The computational fluid dynamics method was adopted to study the gas–liquid separation process considering the wall film model. The interaction between the droplets and gas was solved by Euler–Lagrange method, whereas the forming and stripping of the wall film was studied by Eulerian wall film model. The results reveal that superficial velocity affects the re‐entrainment significantly, and there is a critical superficial velocity determining the occurrence of wall film stripping. According to this work, the critical velocity for air continuous phase is 11.2 m/s. It is found that the discrete phase content and droplet size have no effect on film thickness but affect the separation efficiency. The molecular viscosity and the density of continuous phase affect the Eulerian wall film on two aspects. First, the critical stripping velocity decreases with the increase in molecular viscosity. Second, the film average thickness and separation efficiency decrease with the increase in the product of viscosity and density of the continuous phase. Because the high velocity causes some unsteady of the results, the bulk velocities lower than 20 m/s are recommended. The development of re‐entrainment mechanism provides a good understanding of inertia separation.

UU-type parallel mini-hydrocyclone group for oil-water separation in methanol-to-olefin industrial wastewater

Methanol to olefin (MTO) process is a chemical technology for producing low-carbon olefins from coal-based or natural gas-based methanol. It has changed the pattern of low-carbon olefins relying on petroleum cracking, and opened a new process for producing low-carbon olefins. However, the wastewater generated in the MTO process is difficult to handle. Numbering-up of mini-hydrocyclone is often used to enhance the processing capacity of wastewater treatment when mini-hydrocyclone is used for oil-water separation in methanol-to-olefin process. In this paper, the efficiency and pressure drop distribution of a single mini-hydrocyclone were studied in the laboratory. In addition, according to the UU parallel configuration model, 150 mini-hydrocyclones arranged in parallel were established and used for the oil-water separation process of methanol-to-olefin reaction wastewater. The industrial operation results show that the average flow rate of long-period operation is 282 m3/h, the average pressure drop was 0.31 MPa, and the average separation efficiency of the mini-hydrocyclone group was 90 %. Especially for heavy components such as alkanes and aromatics, it had a good separation effect. Thus, it is shown that the mini-hydrocyclone group has good applicability in oil-water separation.

Efficient in-situ separation design for long-term sophorolipids fermentation with high productivity

Until now, the production of microbial biosurfactants has been limited to the use of first-generation (food) substrates. Moreover, the results on sophorolipids yield and productivity reported by state-of-the-art fed-batch processes for sophorolipids production remain unsatisfactory and lead to a significantly high cost per kg of the product. With an aim to address these problems, this study demonstrates a long-term and high-efficiency sophorolipids production method using a semi-continuous integrated production-separation system which utilizes food waste as a substrate. An average volumetric productivity of 2.43 g L −1 h −1 and the overall sophorolipids yield on the substrate (i.e. the combination of glucose and oleic acid as carbon source) of 0.73 g g −1 was achieved within 240 h by fed-batch and separation fermentation. Moreover, the potential of sustaining high production efficiency during long-term fermentation times (480 h) was investigated. No reduction in process efficiency was observed, i.e. average volumetric productivity and an overall sophorolipids yield of 2.39 g L −1 h −1 and 0.73 g g −1 were obtained, respectively. Notably, a very high biomass concentration of 117.2 g L −1 was observed in fed-batch fermentation and separation, which is the highest cell density ever reported for Starmerella bombicola . The separation efficiency was also calculated to evaluate the in-situ separation performance of the developed process quantitatively. In 480-h fermentation, the average separation efficiency of 74.3% and overall separation efficiency of 93.0% was achieved after six separation cycles, suggesting that both separation design and process control were successful in laboratory-scale fermentation. These findings demonstrate the potential of the developed sophorolipids fermentation-separation system for application at industrial scale. • Food waste was used for sophorolipids (SL) fermentation. • Combination of fed-batch with an in-situ separation strategy was developed. • An average productivity of 2.4 g L −1 h −1 was obtained in 480 h fermentation. • A yield of 0.73 g g −1 of carbon added was achieved. • A cell density of 117.2 g L −1 and separation efficiency of 93.0% were achieved.

Efficient separation of tumor cells from untreated whole blood using a novel multistage hydrodynamic focusing microfluidics

Significant progress on circulating tumor cells (CTCs) has profound impact for noninvasive tumor profiling including early diagnosis, treatment monitoring, and metastasis recognition. Therefore, CTCs based liquid biopsy technology is taking a rapid growth in the field of precision oncology. The label-free approaches relied on microfluidic chip stand out from a crowd of methods that suffer from time consuming, extensive blood samples, lost target cells and labor-intensive operation. In this paper, a label-free separation microfluidic device was developed using multistage channel, which took full advantage of inertial lift force. Our strategy demonstrated CTCs were efficiently isolated from untreated human blood samples including antibody conjugation and erythrocyte lysis. This device was applied for isolating human brain malignant glioma cells that were spiked in human peripheral blood samples. The experimental condition was optimized and exhibited an average separation efficiency of ≥ 90% across cell morphological analysis, up to 84.96% purity of collected CTCs and the viability of all cells is >95%, which was better than other one-step CTCs separation methods. Furthermore, the CTCs were successfully separated from untreated clinical blood sample of cancer patient on the proposed microfluidic device. The entire experimental procedures are extremely low-cost and easy manipulation. It is believed that the proposed multistage microfluidic chip can become a promising tool for CTCs separation and early diagnosis of cancer.

A performance analysis of inverse two-stage dynamic cyclone separator

On account of low removal efficiency of fine coal, low available pressure and large range of gas fluctuation during the CBM exploitation process, an inverse two-stage dynamic cyclone separator is proposed to solve these questions. In the present study, the mechanisms and performance of the separator are investigated through the combination of experimental and numerical methods. The results show that the average separation efficiency of the 5 μm particles in the inverse two-stage dynamic cyclone separatr is 91% when the inlet flow rate of 20, 000 m3/d and rotational speed is 1500 rpm. Moreover, it is found that the pressure drop increases with the increase of the impeller speed and flow rate, and it is roughly linear. The internal rotational flow field of the separator is controlled by adjusting an external motor so that the device can adapt to a wide range of fluctuations. When the impeller speed is 1500 rpm, the separation efficiency of the particle with a mean diameter of 10 μm reduces by 3% when the flow rate increases to 125% of the nominal flow and the separation efficiency increases by 3.5% when the flow rate reduces to 75% of the nominal flow.