Dust Removal Performance Research Articles

Analysis of fabric movement and dust removal performance due to twist motion in a clothing care system

This study aims to explore effective dust removal methods for the improvement of clothing care systems by analyzing the fabric movement caused by the twist motion and examining its influence on dust removal performance. The finite element method simulation was used to model the tension at different vertical and horizontal positions of the fabric as a spring array, to calculate the fabric movements at each position over time when a twisting force was applied and enable comparison with experiments. When observing the fabric movement due to the twist motion with actual fabrics, silk showed the greatest movement, followed by cotton and linen. Cotton experienced decreasing force from the top to the bottom, with increased amplitude at the bottom due to fluttering caused by the bottom not being fixed. When examining the fabric movement according to the velocity, slower velocity did not effectively transmit twist force to the bottom, while faster velocity resulted in more small movements. The analysis revealed that greater force at faster velocity led to better dust removal performance. Therefore, for efficient dust removal, the force transmitted to the fabric should be increased. Most dust is removed within the first 10 min, so exerting a strong force for a short duration is important.

Maintaining solar cell efficiency realized by high-transparency dual-function SiO2 coating with self-cleaning and dust removal

Addressing the issue of dust deposition on photovoltaic (PV) panels is of profound scientific significance and practical value for enhancing PV power generation. Transparent superhydrophobic coating is expected to be applied in the self-cleaning of PV panels. However, developing the transparent superhydrophobic dust removal coatings remains a challenge. Herein, we developed a highly transparent F-SiO2 coating with dual self-cleaning and dust removal functions, composed of polydimethylsiloxane (PDMS) and SiO2. The coating demonstrates a high transmittance of 97 %. After self-cleaning and dust removal tests, conversion efficiency of F-SiO2 coated PV decreased by only 0.03 % and 0.01 %, respectively, demonstrating excellent self-cleaning and dust removal performance. Additionally, the F-SiO2 exhibits high stability. Mechanism analysis of dust removal performance reveals that the decreased effective dielectric constant from the porous structure and the reduced actual contact area between the particles and the superhydrophobic surface, thereby effectively reduces the van der Waals force between dust and coating. This work provides a novel strategy to prepare self-cleaning and dust removal coatings on PV cover plate.

Analysis of the influence of dust particles in the peanut pickup harvester with a self-designed axial-flow dust-fall box on its dust suppression performance

The atmospheric particulate pollution poses a serious threat to human health and ecological environment. The dust particle pollution caused by the operation of agricultural machinery is becoming increasingly severe and the peanut pickup harvesters are widely used in agricultural operation. Therefore, it is necessary to reduce the concentration of dust particles in the work of peanut pickup harvesters. In this study, a self-designed dust-fall box composed of multipleaxial flow cyclone tubes in parallel was integrated with the peanut pickup harvester. Based on the CFD-DPM model, simulation analysis was conducted to explore the effects of different inlet velocities, different numbers of swirling blades, and two types of exhaust port on the dust removal performance of the cyclone. The Box-Behnken design was used to determine the optimal structural parameters of the axial flow cyclone. The influence of the pressure distribution and velocity variations of the internal flow field on the dust removal efficiency of the two schemes was simulated and analyzed. Thereafter, a reasonable parallel scheme of multiple axial flow cyclone tubes in the dust-fall box was determined. The drone was used to monitor dust in peanut harvesting operations, and dust particle concentrations at 8 detection points under varying working conditions were recorded. The distribution and diffusion rules of dust in harvesting operations were explored through cluster analysis, and the test data obtained were compared with numerical calculation results to verify the accuracy of numerical calculation. The results showed that for a single axial flow cyclone, when the inlet wind speed was 6 m/s to 8 m/s and the number of swirling blades was 4, the structural parameters of the cyclone separator had significant influence on the separation efficiency. The influencing factors ranking in descending order were cylinder diameter, cylinder length, and exhaust pipe insertion depth, respectively. To be more precisely, the separation efficiency was best when the cylinder diameter was 60 mm, the cylinder length was 150 mm, the insertion depth of the exhaust pipe was 50 mm and the cone angle was 20°. It was more reasonable to use 8 axial flow cyclone tubes in parallel, and the maximum separation efficiency can reach 84.21 %. Field operations showed that the numerical calculation results were similar to the actual harvesting process. The dust particle concentration in the peanut harvesting operation equipped with a dust-fall box was always lower than 10 mg/m3. The dust particle concentration was the highest at the rear of the whole machine and the lowest near the cab. Compared conventional harvesters, the harvester with a dust-fall box reduced its dust particle concentration by 64.37 %; the concentration of 30 μm dust particles was reduced by 69.31 %; the dust particle concentration at the rear of the whole machine also effectively reduced. This study can provide reference for controlling dust emissions during peanut harvesting operations and agricultural machinery harvesting operations.

Experimental study of drag characteristics and dust removal performance of a hybrid wet-filter precipitator

Experimental study of drag characteristics and dust removal performance of a hybrid wet-filter precipitator

Research of dust removal performance and power output characteristics on photovoltaic panels by longitudinal high-speed airflow

Photovoltaic (PV) panels' photoelectric conversion efficiency will decrease as dust deposition on their surface. An approach to dust removal on the PV panel's surface by longitudinal high-speed airflow was investigated to increase the output power. In this paper, commercial CFD software was used to numerically simulate the characteristics of dust removal by longitudinal high-speed airflow. The PV panels' output characteristic model under the action of dust removal by high-speed airflow is established by Simulink software, and the influence of high-speed airflow on the output characteristic is studied. Firstly, the dust removal mechanism of the PV panel under high-speed airflow is studied. Secondly, the impact of different tilt angles of the PV panel, dust particle size, airflow velocity, and blowing time on the dust removal effect of the PV panel surface were studied. The optimal airflow velocity and blowing time were obtained according to the airflow velocity and blowing time and their influence on the dust removal rate. Finally, the effect of high-speed airflow dust removal on PV power generation's efficiency and output characteristics is studied. The findings demonstrate that as the tilt angle increases, so does the dust removal rate increases continuously. In addition, the rate at which dust is removed increases with airflow velocity and blowing time. When the tilt angle is 30°, the best airflow velocity of dust removal is 5 m/s, and the best blowing time is 8 s. When the tilt angle is 45°, the best airflow velocity of dust removal is 10 m/s, and the best blowing time is 5 s. With the increase in airflow velocity and blowing time, the output power of PV panels continues to increase. When the airflow velocity is 10 m/s, and the blowing time is 5 s, 7.5 s, 12.5 s, and 15 s, the maximum output power after dust removal is increased by 15.44 %, 23.05 %, 23.38 %, and 23.39 %. This paper's research results can guide the design of the practical engineering application of longitudinal blowing high-speed airflow in the dust removal of PV panels.

Dust removal by water spray, condensation and defrosting based on superhydrophobic fin surface

Dust deposition on the fin surface of the outdoor heat exchanger seriously affects the operating efficiency of the air source heat pump (ASHP). Considering the operation characteristics of ASHP in summer for cooling and in winter for heating, a dust removal strategy is proposed based on superhydrophobic fin surface (SFS). In summer, the SFS is sprayed to remove dust by collecting the condensate water of air conditioning. In winter, by coupling the dust deposition with the condensation or frosting/defrosting phenomenon on SFS, the self-propelled motions of condensate droplets or the peeling off of the frost layer in defrosting is used to realize the dust removal. The experiment results show that the water spray on SFS has excellent dust removal performance, and the deposited dust is completely removed after 2 sprays. The dust is carried away by the jumping or gliding of the water droplets. The condensation has poor dust removal performance and takes long removal time. After several hours of condensation, the dust removal rate is 89.6 % and 40.0 % on SFS under different dust deposition levels. Due to the peeling off of the frost layer from the SFS at beginning of defrosting, the melting water at the bottom of the frost layer carries the dust away from the fin surface effortlessly. After 2 defrosting cycles, the dust removal rate reaches 99.6 %, while it is 50.1 % on the bare surface. Therefore, the strategy of dust removal by water spray in summer and defrosting in winter is suitable for ASHP.

Robust and transparent dust removal coating applied to polyimide-based photovoltaic modules for lunar rovers

Dust removal coatings for polyimide (PI)-based photovoltaic modules used in lunar rovers were fabricated successfully through the blade-coating method using silicon dioxide (SiO2) nanoparticles and γ-aminopropyltriethoxysilane (KH550). The dust removal performance, morphology, transparency, and adhesive force of the coating can be optimized by adjusting the pH and the mass ratios of SiO2 and KH550. The designed coating demonstrates excellent dust removal performance, achieving an percentage of over 85 %. Moreover, the coating has minimal impact on the transparency of the PI substrate and exhibits strong adhesion to it. Additionally, the coating shows remarkable resistance to both high and low temperatures. Even after undergoing five cycles of thermal treatment ranging from −196 to 160 °C, there were no significant changes in the morphology or dust removal performance of the coating. Therefore, this coating exhibits tremendous potential for application in the dust removal of photovoltaic modules in lunar rovers.

Dispersion and migration characteristics of multisource respirable dust in development panels during tunnelling processes

Underground miners in Australia are facing continued threats from dust-related diseases. To address these issues, improved knowledge of airflow migration patterns and respirable dust dispersion characteristics within a continuous-miner-driven heading under an exhausting ventilation system is required. Based on site-specific conditions of a development heading in New South Wales, a three-dimensional computational fluid dynamics (CFD) model was constructed and validated with onsite dust monitoring data, where a good agreement was achieved. Three scenarios of coal cutting at the middle, floor and roof positions were considered and simulated, with dust generated at four different sources. The simulation results indicated that the operators on the left-hand-side (LHS) with the extraction duct should be equipped with fit-for-purpose personal protective equipment and stay behind the ventilation duct inlet during coal cutting process, while miners standing at the right-hand-side (RHS) of the continuous miner for roof and rib bolting and machine operating should stay immediately behind the roof and rib bolting rig where dust concentration is relatively low. In addition, an increase in airflow rate through the exhausting ventilation duct or a reduction in the distance from the duct inlet to the heading face assisted in reducing dust levels within the heading, particularly at the LHS of the continuous miners. Finally, compared to the scenario of the current ventilation scheme, an on-board exhausting ventilation system could improve dust removal performance, with dust concentration at the breathing level reducing by approximately 43.6%. This modelling study can advance the understanding of multi-source dust diffusion characteristics in the heading face and provide guidance on dust mitigation, thus improving the health and safety of miners and creating a cleaner underground working environment.

Performance and mechanism of atomizing dust removal from APG12/Active Water: Experimental and molecular simulation study

Coal mining processes produce large amounts of dust particles that seriously pollute the environment and threaten health. Spraying technology is a primary technique for dust removal. To date, experimental methods are mainly applied to study the atomization and dust removal properties of water droplets, but the intermolecular mechanism involved is unclear. First, a test platform was assembled to evaluate the atomization and dust removal performance of APG12/active water. Then, APG12 droplet and APG12 droplet/anthracite molecular models were constructed, and the underlying mechanism was elucidated through molecular simulation. The experimental results showed that the droplet diameter of the APG12/active water spray decreased by 14.15%, and the dust removal efficiencies of total dust and respirable dust increased by 39.55% and 61.51%, respectively. The simulation results indicated that APG12 molecules and H2O molecules exhibited attractive interactions. This interaction weakened the electrostatic attraction between the H2O molecules in the APG12/active water droplets. Moreover, the interaction enhanced the repulsive van der Waals interactions, reduced the number of hydrogen bonds, and increased the diffusion coefficient of H2O molecules. As a result, the droplets were relatively easy to break. In addition, APG12 molecules covered the surfaces of anthracite molecules, thus increasing the surface oxygen content and the electrostatic attraction, van der Waals forces and hydrogen bonding between H2O and coal molecules. This enhancement, in turn, improved the wettability of coal dust. Herein, the molecular mechanism of dust removal from APG12/active water was analysed, providing guidance for the development of new dust suppressants.

An empirical study on thermal efficiency and dusty moisture removal efficiency using enthalpy wheel in industrial waste incineration plant

In this work, an empirical study is conducted on the waste heat recovery and moisture removal performance of an enthalpy wheel installed in an industrial waste incineration plant. The enthalpy wheel made of a metal mesh is placed in parallel with the wet scrubber of the incineration plant to exchange heat with high-temperature exhaust at 200 °C. In the enthalpy wheel, exhaust gas and external air exchange heat in the form of a counter flow, and the condensation effect is maximized by installing a water-spray nozzle at the inlet of the enthalpy wheel. Empirical data were collected over 100 days spanning July to October. To evaluate the performance of the enthalpy wheel, thermal efficiency, moisture removal efficiency, and dust removal efficiency were tested under high-temperature humid conditions. In some results, the overall thermal efficiency reached peaked at 61.2 %. Regarding moisture removal performance, the average moisture removal rate was 493 kg/h, affording an efficiency of 49.2 %. In terms of dust removal performance, the average dust removal efficiency was 79.6 %.

Research and application of bag filter system for railway ballast bed coal suction vehicles: An optimization and application study.

The current bag filter system used by railway ballast bed coal suction vehicles for cleaning coal dust from railway tunnels has low operational efficiency and generates significant volumes of dust. This paper describes a simulation test unit designed to enhance the dust removal performance in railway tunnels. The flow field inside the simulation test unit is investigated under different operating conditions through numerical simulations, and the variations in air volume and working resistance, total dust collection efficiency, and optimal operating parameters of a pulse cleaning system are identified through a series of experiments. The numerical results show that the pulse cleaning system does not significantly affect the uniformity of the flow field distribution at the bottom of the filter cartridge during the process of operation. The experimental research indicates that the simulation test unit satisfies the design requirements, achieving an average total dust removal efficiency of 99.93%. A field application shows that the total dust mass concentration at the operator position can be reduced from 335.8 mg∙m-3 to 4.2 mg∙m-3, effectively improving the operating environment within the tunnel.

Influences of voltage allocation and magnetic field introduced position on the dust removal performance of multi-electric field ESP

Improving the removal efficiency of PM2.5 particles is significant for the limitation of particle emissions from coal-fired power plants. This work reports a multiple electric field electrostatic precipitator (ESP) enhanced by magnetic confinement effect to efficiently remove PM2.5 particle from flue gas. Firstly, the electromagnetic dust removal mechanism of PM2.5 capture in multi-electric field ESPs is revealed, and the theoretical and numerical models of the multifield coupling under the effect of magnetic field are established. Secondly, the potential distribution law under different working voltages and the dust removal performance for PM2.5 are analyzed, and the magnetic field effect under the optimal voltage allocation is numerically simulated. Finally, the best magnetic field introduction position under the optimal voltage allocation is investigated. The numerical results show that the optimal voltage allocation and the best magnetic field position are determined to achieve the full effect of magnetic field to improve the PM2.5 dust removal efficiency in the multi-electric field ESP under the premise of ensuring the decrease of voltage load. The relevant results can provide ideas and references for greatly reducing PM2.5 emissions and voltage power consumption in thermal power plants.

Dust-removal performance of an improved spherical cylindrical ECP under magnetic confinement effect

In order to further improve the trapping effect of fine particles, an improved electrostatic cyclone precipitator (ECP) was proposed. The electromagnetic dust-removal mechanism of spherical cylindrical ECP was revealed, and the influences of flue gas velocity on the dust-removal effect of fine particles with and without magnetic confinement effect were discussed. The results show that the overall efficiency curve of fine particles shows a ' hump ' type with the change of flue gas velocity, and the increase of magnetic induction intensity promotes the hump to move to the low flue gas velocity area. Increasing magnetic induction intensity can improve the trapping performance of spherical cylindrical magnetically constrained ECP, and the improvement effect weakens gradually when the same amplitude increases.

Influence of aerodynamic pressure on dust removal by supersonic siphon atomization

At present, there are many problems in coal mine operation, such as formation of large amounts of dust, complex dust migration behavior, severe respiratory harm, poor on-site performance of spray dust removal technology under windy conditions, and low collection efficiency of respirable dust. To solve the above problems, the finite element method of computational fluid dynamics (CFD) was used. The Spalart-Allmaras turbulence model of COMSOL software and the tracking module for atomized particles broken by droplets were used. They were combined with the Fraunhofer diffraction principle to study the distributions of the velocity of the airflow field, droplet size, droplet velocity and wind resistance for a supersonic water siphonic atomization device. The influence of the above factors on dust removal at different aerodynamic pressures was studied experimentally. The relationships between spray characteristics, flow field velocity distribution, dust removal effect and spray characteristics were revealed. The research showed that with increasing pressure, the supersonic component accounted for an increased proportion of the flow field inside the nozzle, average velocity of the flow field increased, atomization efficiency increased, droplet particle size decreased, and droplet velocity increased. The particle size of the droplets first increased, then decreased and then increased with increasing spraying distance. Additionally, the range of high-speed fine droplet size fog increased with increasing pressure. At the same transverse wind speed, with increasing pressure, the deflection point of the fog field moved backward, and the wind resistance of the spray was enhanced. With the increase in aerodynamic pressure, the dust isolation and negative pressure effect of spray and the dust collection efficiency increased, and there was an optimal value for dust removal in a limited space. The reason was that when the pressure increased to a certain extent, the air flow reversed in the coil at the bottom of the limited space, which blew the dust that was not aggregated at the bottom away from the area where dust was falling. Thus, the dust was entrained in fog droplets but could not be removed from the air flow. The dust dispersion in the air flow after purification differed greatly at different pressures because the removal efficiency of dust in the 2.5–10 μm particle size range was mainly affected by the pressure. In a field study of a fully mechanized mining face, the fog curtain formed by the device covered the whole section under the condition of airflow disturbance with large transverse velocity, and the comprehensive respirable dust removal efficiency of the working area reached 92.3%. Thus, this method showed good wind resistance and dust removal performance. The study of this technology can provide a clean working environment and theoretical guidance for the safe production of coal in the future, especially for fully mechanized mining faces.

Experimental study on the atomization characteristics and dust removal efficiency of a fan-shaped nozzle for purifying working environment

The inadequacy of the existing research in characterizing the atomization performance of the whole atomization field by the local region at nozzle axis hinders the improvement of dust removal performance of a spray system, especially for fan-shaped nozzles with large atomization angle. To solve this inadequacy, 88 measuring points were designed in this study to reveal the spatial distribution characteristics of atomization parameters of a fan-shaped pressure atomization nozzle using a 3D Fiber Phase-Doppler Anemometer. Moreover, the atomization performance and dust removal performance of the whole atomization field under different spray pressures were characterized. The results showed that the spatial distribution of atomization parameters in the axis and radial direction of the nozzle was inhomogeneous. As the axial distance from the nozzle outlet increased, the average droplet size showed a trend of first decreasing and then increasing, the proportion of the droplet of 15-70 μm showed a trend of first increasing and then decreasing, while the average droplet velocity and droplet flux showed a decreasing trend. In addition, the spray orientation was perpendicular to gravity, and the atomization field was parallel to gravity, resulting in a significant difference in the average droplet size between the upper region and the axis. Compared with the upper and lower regions, the atomization effect at the axis was superior, manifested by higher average droplet velocity and droplet flux, indicating that characterizing nozzle atomization performance with atomization parameters at the axis will lead to overestimation. The increase of spray pressure can improve atomization performance and dust removal efficiency to a certain extent, but the improvement effect had a limit. The atomization field can be divided into atomization region, expansion region and contraction region, and the expansion region was considered as an effective dust removal region. These findings provide reference for the design and operation of a spray system.

Study on the wet dust collection mechanism of metal-based filter screens and the effect of its inclination angle on dust removal performance

The wet filter dust collector (WFDC) is widely used in dust control in various industries, but its dust collection mechanism is unclear, and the influence of the metal-based filter screen (MBFS) inclination angle on the dust removal performance is still uncertain. In this paper, the liquid film crushing and collecting dust mechanism of MBFS and the influence of its inclination angle on the dust removal performance of WFDC are studied. The results show that with the increase of inclination angle (30° to 150°), the average pressure drop of WFDC first decreases and then increases, the average dust concentration first increases and then decreases, and the MBFS dust removal performance is optimal at 90°. The optimized WFDC was applied on-site in a coal preparation plant, which exceeded the dust suppression efficiencies of 91 % and 88 % for total dust and respirable dust, respectively. The research results are expected to provide theoretical guidance for WFDC design and improvement.

Design and fabrication of dust removal nanoarray structure on the surface of solar cell glass cover

A nanoarray structure was constructed on the quartz glass cover surface, which had both strong dust removal ability and significant anti-reflection. Firstly, a structure model of dust removal nanoarray was established to investigate the effects of the structural parameters such as the period, the depth, and the duty ratio. Then a nanoarray structure was prepared on the glass surface with nano-imprinting and plasma etching, then modified with atomic layer deposition to adjust its structural parameters. The results show that the dust removal performance of the glass cover improved by about 14% after being constructed a 500-nm period nanoarray structure. As the etching time and the number of deposited layers increased, the dust removal performance first increased and then decreased. After 30 min etching and 50 layers of atomic deposition, the nanoarray improved the dust removal performance of the glass cover by about 45%. Moreover, this nanoarray structure also had an obvious anti-reflection function, improving the transmittance within 350–1100 nm of the glass cover by 0.63% before dust fall, by 1.23% after the dust fall at a 30° inclination angle, and by 1.51% at a 60° inclination angle.

Investigation of velocity distribution in channels and chambers of the electrostatic precipitator at TPP Nikola Tesla Unit A1

To achieve the optimum dust removal performance of an electrostatic precipitator, the flue gas should be distributed uniformly over its vertical cross-section. The flow in the upstream flue gas ducts has a significant influence on the downstream gas distribution in the chamber of the precipitator. This paper presents the results of homogeneity assessment of velocity distribution in the ducts and vertical cross-sections of the electrostatic precipitator of Unit A1 at the Nikola Tesla thermal power plant in Obrenovac. The measurements confirmed that the reconstruction of the vertical chamber at the front of the precipitator, which was carried out during the overhaul in 2020, effectively solved the problem of the original asymmetric arrangement of the vertical flue gas ducts. Nevertheless, the analysis revealed poor homogeneity of the flow field through the chambers. Therefore, additional measures must be taken to increase the dust removal efficiency of the precipitator.

Research on Effects of Dust Removal Using Ultrasonic Vibrators.

This work presents two types of ultrasonic vibrators in order to comparatively analyze their dust removal properties for microscopic particles. The vibrators were constructed by pasting four piezoceramic (PZT) plates onto the upper surface of a rectangular metal substrate. The longitudinal or bending mode is excited to form a standing wave in the vibrators. The superposition of the longitudinal and bending modes generates a traveling wave. Because the bending and longitudinal vibrations are two different modes, the process of tuning their resonant frequencies to be close is necessary for the traveling wave vibrator. The structural parameters of the vibrators were optimized by the finite element method. During experiments, the dust removal performances of these vibrators were evaluated by dumping cigarette ash or alumina powders randomly on the surface of the prototype vibrators. The measured experimental results indicate that the dust removal performance of the traveling wave oscillator is better than that of the standing wave oscillator. The two operating modes of the traveling wave vibrator produce orthogonal vibration displacements on the vibrator driving points. Vibration in one direction generates friction force, which drives adherent dust particles. Vibration in the other direction provides intermittent contact pressure between the vibrators and deposited dust particles. The synthesized elliptical motion of vibrator particles helps to improve the dust removal characteristics of the vibrators. The simple structure of the developed vibrators makes them the most promising candidates for dust removal from engines, camera lenses, car windows, and navigation systems.

An Efficient Ash Cleaning Method for Flat Box Cartridge Filter: Structure, Parameters and Cleaning Mechanism of Slotted Blowing

The problem of serious ash accumulation at the lower part of flat box filter cartridges is an important limitation for the improvement of ash cleaning efficiency in this kind of filter. To solve the above-mentioned problem, the type of slotted blowing hole impacting the performance of the ash removing under the same ash cleaning area was studied. In the present work, a total of four types of slotted blowing holes with different length were designed. The influence of blowing distance and blowing pressure on dust removal performance were investigated. Numerical simulation was conducted to demonstrate the mechanism of the dust removal process. An industrial coating test was also carried out to investigate and verify the actual ash cleaning performance under the optimal conditions as obtained from the above investigations. The results showed that: (1) the performance of dust cleaning produced by a three-slit blowhole was better than that by a four-slit blowhole; (2) 0.2 MPa was determined to be the optimal blowing pressure, which meets the requirement of ash cleaning; (3) 20 mm was selected as the optimal blowing distance, as this was the distance at which the surface side wall pressure at the non-positive-to-blow hole area was obviously increased, indicating that the whole performance of ash cleaning could be improved. The results obtained in this study are of great significance for improving the efficiency of dust removal in the use of flat box filters, promoting the development of dust removal technology, protection of environment, and reduction of human health damage.