Dust Collection Research Articles

Fine dust collection capacity of a moss greening system for the building envelope: An experimental approach

Air pollution is one of the most impactful environmental issues worldwide in terms of mortality. Numerous studies have assessed the benefits of vertical greening systems within urban areas for mitigating air pollution, but their widespread adoption is limited by high costs and maintenance requirements. The current study assesses the air pollution mitigation capacity within urban areas of three moss species: Barbula unguiculata, Grimmia pulvinata and Homalothecium sericeum, used in the moss envelope system called MosSkin. Following a three-months exposure of the three moss species samples in a highly trafficked area, phyllids were analysed with Field Emission Scan Electron microscopy to quantify number, dimension, and nature of particle deposition on leaves on their different portions (base, centre, apex). The moss species chosen collected up to 45,580 particles per mm2 with the trend H. sericeum ≥ G. pulvinata > B. unguiculata, showing a similar tendency in terms of classes and order of magnitudes. However, specific higher affinities for PM fractions 2–7.5 μm were shown by G. pulvinata. The PMx collection can be related to species-specific shape of leaves within stems, and it depends on the leaf portions (highest capture in apex), 45–55 % consisting of PM0.5 μm, indicating a significant collecting capacity of such fractions.

Assessment of the microbial contamination in "Do It Yourself" (DIY) stores - a holistic approach to protect workers' and consumers' health.

In "Do-It-Yourself" (DIY) stores, workers from the wood department are considered woodworkers. Given the health risks associated with woodworking, particularly from fungi and their metabolites, this study aims to assess microbial contamination and health risks for both workers and customers. The study was developed in 13 DIY stores in Lisbon Metropolitan Area, Portugal. It employed a comprehensive sampling approach combining active (MAS-100, Andersen six-stage, Coriolis μ, and SKC Button Aerosol Sampler) and passive (electrostatic dust collectors, surface swabs, e-cloths, settled dust, filters from vacuumed dust, filtering respiratory protection devices, and mechanical protection gloves) methods to assess microbial contamination. A Lighthouse Handheld Particle Counter HH3016- IAQ was used to monitor the particulate matter size, temperature, and humidity. The wood exhibition area presented the highest fungal load, while the payment area exhibited the highest bacterial load. MAS-100 detected the highest fungal load, and surface swabs had the highest bacterial load. Penicillium sp. was the most frequently observed fungal species, followed by Aspergillus sp. Mycotoxins, namely mycophenolic acid, griseofulvin, and aflatoxin G1, were detected in settled dust samples and one filter from the vacuum cleaner from the wood exhibition area. Cytotoxicity evaluation indicates the wood-cutting area has the highest cytotoxic potential. Correlation analysis highlights relationships between fungal contamination and particle size and biodiversity differences among sampling methods. The comprehensive approach applied, integrating numerous sampling methods and laboratory assays, facilitated a thorough holistic analysis of this specific environment, enabling Occupational and Public Health Services to prioritize interventions for accurate exposure assessment and detailed risk management.

Investigation of the potential of in-line particle concentration measurements in gas particle separation processes by using low-cost particulate matter sensors

In addition to the costly laboratory-based particle measurement devices, low-cost particulate matter sensors for ambient air quality measurements can also be employed for the detection of PM in gas cleaning devices. The ability to spatially resolve the actual level of particle number concentration with high temporal resolution within a gas-particle separation process is of significant value for process monitoring and control. The quantitative reliability of the measurement data from low-cost particulate matter sensors remains uncertain when the particle concentrations in the apparatus exceed the upper measurement limit of the sensors, whether temporarily or permanently. This study examines the potential of low-cost particulate matter sensors for in-line particle concentration measurements in gas-particle separation processes. The measurement performance of the low-cost particulate matter sensors is initially examined under idealised conditions in a dust chamber. This is done in order to quantify the deviations of the low-cost particulate matter sensors in comparison to a state-of-the-art precision laboratory high-cost sensor. Subsequently, both sensor types are installed at a wet separator test facility, following the quantification of their respective measurement performances. The low-cost particulate matter sensors are capable of measuring particle number concentration above their specified limit (up to ≈6.1×104cm−3), depending on the measurement conditions. By applying a 3rd polynomial correction function, obtained from the initial quantification measurement, the low-cost particulate matter sensors are able to reproduce the particle number concentration measured by the high-cost sensor. Furthermore, the low-cost particulate matter sensors are capable of reproducing short-term fluctuations in the particle number concentration.

Acoustic characteristics of the operating noise of vacuum cleaners that evoke the feeling of suction

Vacuum cleaner noise is mostly assessed by the sound when the cleaner is not picking up dust. However, users usually hear the operating noise when the cleaner is picking up dust, and this noise is used to recognize that the cleaner is working properly. Therefore, the vacuum cleaner operating noise during dust collection should be evaluated. Psychoacoustical experiments were conducted on three vacuum cleaner models to evaluate the sound quality of the operating noise when beads or pieces of paper were vacuumed. The results showed a strong influence of loudness. We therefore standardized the loudness of the operating noise at around 20 sone and carried out similar experiments. A relationship was found between the suction feeling and the impression of luxury. Most of the stimuli that evoked both the impression of luxury and the suction feeling were the noises made when there was no suction object. When comparing the acoustic properties of stimuli that evoked strong and weak suction feelings, the operating noise of the appliance itself, especially those with components in the low frequency range up to 500 Hz and in the high frequency range around 10 kHz, was rated as strong suction feeling.

Research on ash accumulation surface measurement methods based on the dot laser principle

Dust collectors are essential environmental protection equipment in thermal power plants. However, in recent years, collapses caused by excessively high material levels in the ash hopper in dust collectors have increased frequently, resulting in serious casualties and significant economic losses. The level gauge of the ash hopper is a crucial device for detecting the material level in the ash hopper and plays a vital role in preventing the ash hopper from collapsing due to excessive material load. However, level gauges of the ash hopper currently in use have various problems. Laser-ranging technology is characterized by concentrated energy, a small divergence angle, and the ability to penetrate dust. We have proposed a new material-level measurement method based on the dot matrix laser ranging principle. This method utilizes dot-matrix laser ranging and visualizes the optimized measurement data to ultimately derive information about the material surface's morphology and level. A physical hopper model is used to conduct verification experiments on various material surface morphologies, material levels, and the material hanging on the hopper wall. The results indicate that this method can accurately identify the material level and the material hanging on the hopper wall, preventing false alarms due to “false material levels.”

Investigation into the hydrogen inhibition mechanism of Platycladus orientalis leaf extract as a biodegradation inhibitor for waste aluminum-silicon alloy dust in wet dust collectors

This study investigates the risk of hydrogen explosion caused by waste metal dust encountering water in wet dust collectors. It proposes using renewable plant extracts to suppress hydrogen evolution from aluminum-silicon (Al-Si) alloy dust, aiming to achieve intrinsically safer production. Platycladus orientalis leaf extract (POLE) was prepared using water as a solvent. Hydrogen inhibition experiments, material characterization, and theoretical calculations were conducted to evaluate the effect of POLE on waste Al-Si dust. The inhibition experiments demonstrated that POLE exhibits excellent inhibitory performance. At a POLE concentration of 2.0 g/L, the hydrogen inhibition efficiency reaches 97.71 % after 22 h, with a reaction rate constant of 8.9708 × 10−5, approaching zero. This efficiency remained stable over 5 days. POLE formed a uniform, dense protective film on the Al-Si dust surface, with a contact angle of 99.23°. FTIR spectra revealed absorption peaks corresponding to POLE functional groups and Al-O bonds, indicating that successfully adsorption of POLE through both physical and chemical interactions. Finally, theoretical calculations were performed to further explain the hydrogen inhibition mechanism of POLE, supplementing and confirming the characterization data. This study inhibited hydrogen production from waste dust, offering a new approach to enhancing the hydrogen production rate from recycled Al scraps.

TREATMENT OF COPPER FLUE DUST FROM FLASH FURNACE WASTE HEAT BOILER FOR IMPURITIES CONTROL

During the pyrometallurgical processing of copper sulphide raw materials, part of the charge leaves the furnace space together with the exhaust gases in the form of dust entrainment. Volatile components also pass into the dust-gas flow, due to which it is enriched with impurities, some of which are harmful to the technological process. The formed dust-gas flow passes through dust collection equipment, where the main part of it is captured. Most often, the captured dust is recirculated, which leads to a decrease in the productivity of the furnace unit and a gradual increase in the content of impurities in the condensed products of the smelting. To overcome these disadvantages, it is necessary to take part or all the recirculating dust out of the melting cycle and process it independently to extract the valuable metals and dispose of the harmful substances. In metallurgical practice, industrial application for the processing of recirculating dust entrainment has mainly been accomplished by hydrometallurgical methods based on treating the flue dust in aqueous solutions of acid or alkaline reagents. In the present research work, laboratory results on hydrometallurgical leaching of flue dust from a flash furnace waste heat boiler (FF-WHB) are presented. The effect of the main technological parameters affecting the degrees of recovery of the main metals in solution was studied. Based on the experimental results, the optimal conditionsfor hydrometallurgical treatment of the FF-WHB flue dust were determined. By treating the dust under optimal conditions, the main tasks of the research are achieved - removal of impurities harmful to the technological process and reduction of the amount of flue dust processed in the flash furnace.

大型贮罐清理机器人吸尘系统的设计与研究

Taking the large storage tank as the cleaning object, a cleaning robot integrating shoveling, crushing, sweeping and dust-absorbing was developed, and its dust-absorbing system was analyzed and optimized. Firstly, Fluent-EDEM gas-solid coupling was utilized to simulate the dust-absorbing system. By analyzing the fluid distribution and particle trajectory, the internal structure of the dust collection box was optimized to reduce the dust particles entering the fan box. Then, by analyzing the structural parameters of the suction nozzle, the influence of the nozzle shoulder angle, nozzle length, and shoulder height on the dust-absorbing effect was explored, and the parameters were determined, so as to reduce the energy loss and increase the flow rate on both sides of the nozzle. Finally, through the dust suction test, different models of nozzles were tested for dust suction, and the wind speed at the nozzle was measured, and the leakage of dust particles on both sides of the nozzle was significantly reduced after optimization, which verified the reliability of the simulation results and provided a theoretical basis for the design of the sweeping robot.

Effect of High-Voltage Electrostatic Precipitator Dust Collection Plate Structure on Collection Efficiency.

To investigate the effect of changes in the dust collector structure on the flow field and electric field distribution resulting from the secondary flow generated by the corona discharge in the collector coupled with the main flow and to improve the dust collection efficiency of the ESP, a folding plate design has been adopted. A multiphysics-coupled corona discharge and flow field numerical model was analyzed to analyze the internal flow and electric field characteristics of linear flat plates and folded plates with three different pole configurations. The study indicates that the dust collecting plate's structure significantly affects the dust collector's internal flow field and electric field distribution within the dust collector. The near-plate electric field and flow field inside the folded plate type are superior to those of the linear flat electrostatic precipitator. With the augmentation of the inlet velocity, the ionic wind disturbance on the flow field inside the electrostatic precipitator channel gradually decreases. Additionally, the folding plate has a certain inhibitory effect on the influence of the ionic wind. At an inlet velocity of 0.5 m/s, the speed near the folding plate is approximately 20% lower than that of the traditional linear flat plate. The folding plate can effectively reduce the flow velocity near the dust collection plate, thereby reducing the occurrence of particle re-entrainment and improving dust removal efficiency. By comparing the speed at the center line of the plate and near the plate, it is obvious that the speed of model B decreases significantly, and as the number of discharge electrodes increases, the speed decreases more obviously. At the same time, when the dust collection efficiency of the two models was compared, it was found that the working efficiency of the B model has been significantly improved, among which the B3 model has the best dust collection effect.

Methods And Techniques for Collecting Cosmic Dust: Insights from Stratospheric Interplanetary Dust Collections

Methods And Techniques for Collecting Cosmic Dust: Insights from Stratospheric Interplanetary Dust Collections

Hydrogen inhibition of wet Al[sbnd]Li alloy dust collector systems using a composite green biopolymer inhibitor based on chitosan/sodium alginate: Experimental and theoretical studies

Aluminum‑lithium (AlLi) alloy polishing and grinding processes in wet dust collector systems could cause hydrogen fire and explosion. From the fundamental perspective of preventing hydrogen explosions, a safe, nontoxic, and sustainable modified green hydrogen inhibitor based on chitosan (CS) and sodium alginate (SA) was developed in this study and was used as a hydrogen evolution inhibitor for the processing of waste dust from AlLi alloys. The structure and elemental distribution of the synthesized material were characterized through characterization experiments. Hydrogen evolution experiments and a hydrolysis kinetic model were used to explore the inhibitory effect of modified CS/SA on AlLi alloy dust, and the results revealed that the inhibitory concentration of the hydrogen explosion lower limit was 0.40 wt%, with an inhibition efficiency of 91.93 %, indicating an 11.88–61.44 % improvement over that of CS and SA. As the inhibitor concentration increased and the temperature decreased, the hydrogen inhibition effect increased. Characterization experiments and density functional theory showed that CS/SA primarily formed a dense physical protective barrier on the dust surface through chemical adsorption and complexation reactions, interrupting the hydrogen evolution reaction between the metal and water. This study introduces a novel green modified hydrogen inhibitor that fundamentally addresses hydrogen generation and explosion.

Evaluation of Airborne Lead Pollution and Its Association with Children's Urinary Lead Levels

Despite the measures taken by most countries, lead pollution still poses an environmental and health risk to humans, especially children. Therefore, the current study aims to evaluate lead in the air and its impact on children's health. Lead samples from the air and children's urine were collected from three different areas within Kerbala Governorate: the urban city center residential areas, and rural areas as a reference area for comparison. A suspended dust collector was used to collect lead samples, and then the lead concentration was measured using an atomic spectrometer after digesting them with acids. The results of the study showed that the highest concentration of lead was in the center of the urban area (3.150 ?g/m3) and its mean concentration in the air was 1.703 (?g/m3), which is higher than the US Environmental Protection Agency limits, with statistically significant differences between the study areas p < 0.01. The mean concentration of lead in children's urine was 0.622 (?g/dL) with statistically significant differences between the areas p < 0.01. Pearson's correlation coefficient indicated a significant positive correlation between the concentration of lead in the air and children's urine (r = 0.651; p < 0.05). This means that high lead concentrations in children's urine are due to lead air pollution and are an indicator of lead pollution in the environment and warn of potential risks to children's health. Therefore, the study recommends reducing lead emission sources and conducting periodic examinations.

An active-type dust collector that reduces brake wear particle (BWP) emission

An active-type dust collector that reduces brake wear particle (BWP) emission

Study on the application of atomized corona discharge combined with screen electrode in dust collection

This paper presents the design of a novel atomized corona discharge coupled screen electrode dust collector, which integrates electrostatic capture and wet electrostatic dust removal technologies. The upper part of the dust collector features an atomized corona discharge electrode utilizing a threaded-wire hole design with uniform water distribution. This design effectively addresses the issue of electrode fatness that may arise from uneven distribution of the discharge electrode. In contrast, the lower part of the collector is equipped with four side-by-side silk screen electrodes, which serve to expand the dust collection area, facilitate secondary particle capture, and consequently enhance dust removal efficiency. The study delves into a detailed analysis of the impact of various parameters on discharge characteristics and dust removal efficiency, culminating in the identification of optimal parameters.

Development and Performance Evaluation Experiment of a Device for Simultaneous Reduction of SOx and PM

Mitigating air pollutants such as SOx and PM emitted from ships is an important task for marine environmental protection and improving air quality. To address this, exhaust gas after-treatment devices have been introduced, but treating pollutants like SOx and PM individually poses challenges due to spatial constraints on ships. Consequently, a Total Gas Cleaning System (TGCS) capable of simultaneously reducing sulfur oxides and particulate matter has been developed. The TGCS combines a cyclone dust collector and a wet scrubber system. The cyclone dust collector is designed to maintain a certain distance from the bottom of the wet scrubber, allowing exhaust gases entering from the bottom to rise as sulfur oxides are adsorbed. Additionally, the exhaust gases descending through the space between the cyclone dust collector and the wet scrubber collide with the scrubbing solution before entering the bottom of the wet scrubber, facilitating the absorption of SOx. In this study, the efficiency of the developed TGCS was evaluated, and the reduction effects based on design parameters were investigated. Furthermore, the impact of this device on ship engines was analyzed to assess its practical applicability. Experimental results showed that increasing the volume flow rate of the cleaning solution enhanced the PM reduction effect. Particularly, when the height of the Pall ring was 1000 mm and the volume flow rate was 35 L/min, the sulfur oxide reduction effect met the standards for Sulfur Emission Control Areas (SECA). Based on these findings, suggestions for effectively controlling atmospheric pollutants from ships were made, with the expectation of contributing to the development of systems combining various after-treatment devices.

Study of spray atomization law and dust suppression effect of a wet dust catcher on a hydraulic support

To control effectively large dust concentrations and their diffusion during coal cutting and shifting of shearers at fully mechanized mining faces, a wet dust catcher on a hydraulic support was developed. The spray nozzle suitable for wet dust collection devices was optimized through spray experiments, and the effects of the spray pressure Pw and nozzle tilt angle θ on the droplet size and fog field concentration were analyzed with Fluent. The numerical simulation results show that the wide-angle solid cone nozzle (with an X-type swirl core) with a diameter of 2.4 mm, water pressure Pw of 6 MPa, and nozzle tilt angle θ of 10° toward the windward side can form a better water curtain. Finally, the wet dust catcher was applied at a 22104 fully mechanized mining face of the Shangwan Coal Mine. The dust removal rate of the shearer driver reached 86.20 %, and that at other positions reached 85 % on average. Evidently, the hydraulic support wet dust catcher can effectively control the diffusion of coal dust at fully mechanized mining faces.

베인-와이어 적층 구조형 엘리미네이터의 경량설계 및 집진성능

베인-와이어 적층 구조형 엘리미네이터의 경량설계 및 집진성능

Influence of Particle Surface Energy and Sphericity on Filtration Performance Based on FLUENT-EDEM Coupling Simulation

The adhesion of dust particles on the surface of the dust collector tends to cause great resistance to the dust collector and affects the operating efficiency. In order to visualize particles in the filtration process and to grasp the mechanism of particle viscosity and sphericity on filtration performance, a numerical simulation study was conducted to investigate the deposition behavior of particles during filtration, employing FLUENT-EDEM coupling technology. By examining the deposition process, the role of particle characteristics on dust behavior within the entire filtration system was elucidated. The effects of varying particle surface energy and particle sphericity on filtration pressure drop and cake porosity were analyzed. The findings reveal that under the force of the air, particles on the surface of the filter membrane experience compaction, leading to a reduction in the porosity of the formed cake layer. The diminution of porosity serves to impede the air, consequently augmenting the pressure drop across the filtration system and hindering the operational efficacy of the dust collector. As the surface energy of the particles increases, the adhesive forces between particles are intensified, leading to an elevation in the porosity of the cake layer and a subsequent decrease in the pressure drop. When the surface energy of the particles is increased from 0.01 J/m2 to 0.04 J/m2, the porosity experiences a modest increase of only 9.1%, yet the pressure drop is significantly reduced by half, amounting to a decrease of 1594 Pa. Under high particle surface energy, as filtration air velocity increases, particles are compressed, resulting in a decrease in cake porosity and an increase in pressure drop. Concurrently, our findings indicate that as the sphericity of particles increases, their surfaces become increasingly smooth which in turn results in a decreased porosity of the cake layer and, consequently, an elevation in the filtration pressure drop.

Research on the explosion vent external composite disaster induced by dust explosion inside the dust collector

With the help of computational fluid dynamics (CFD) technology, this research focuses on the quantitative effects of the explosion venting area (S), static opening pressure of the vent (Pstat) and dust cloud concentration (CD) on the explosion overpressure, high-speed airflow and high-temperature flame in the explosion venting zone. The results show that the explosion disaster along the explosion venting zone in general shows an oscillating fluctuating trend of attenuation, and the closer to the explosion vent explosion disaster is more serious. The increase of S will enhance the nonlinear change of explosion disaster, and the change law of explosion overpressure is completely opposite to that of high-speed airflow and high-temperature flame. With the increase of Pstat, the coupling effect of air intake pipe and dust collector is strengthened, which further aggravates the spread of explosion disaster. The change of CD has both promoting and restraining effects on the spread of explosion disaster. The maximum overpressure (P), maximum wind speed (V), maximum flame speed (Fs) and maximum flame distance (Fd) in the explosion venting zone are 0.022 MPa, 494.5 m/s, 112.9 m/s and 10.9 m, respectively, and the venting safety distance is more than 11 m. In addition, the degree of impact on explosion disaster is in the following order: Pstat > A > CD. This research can provide a reference basis for the effective prevention and control of the composite disaster external the explosion vent induced by dust explosion inside the dust collector.

Evaluation of pulse-jet baghouse dust collectors' contribution to CO2 emissions

Dust cleaning systems are mandatory for use almost in any manufacturing process. Their market size is expected at US$10.77 billion by 2030 growing from US$7.28 billion in 2022. Removing dust particles is the main purpose of these systems and they make an invaluable contribution to environmental safety. However, while cleaning the air from solid particles, industrial pulse-jet baghouse collectors have an additional impact on the environment that usually is not considered. An analysis of energy consumption at the manufacturing and operation stages of the baghouse dust collectors allows for the evaluation of CO2 emissions. The analysis shows that, given the current state of affairs in the industry, by 2030 manufacturing and operation of baghouse dust collectors over the world will emit 70+ million tons of carbon dioxide additionally to the levels of 2021. To reduce the CO2-related environmental impact of industrial pulse-jet baghouse collectors, among all scientific and technical measures, it is recommended to simply scale up the dust collection system, which involves replacing several low-capacity collectors with one general-capacity collector within one industrial enterprise. This allows for a reduction in energy consumption at the collector manufacturing stage from 3 to 10 times and also ensures a significant reduction in operation energy consumption of the dust collector during its service life.