Dust Particles Research Articles

Research on characteristics and influencing factors of road dust emission in a southern city in China.

One of the primary causes of urban atmospheric particulate matter, which is harmful to human health in addition to affecting air quality and atmospheric visibility, is road dust. This study used online monitoring equipment to examine the characteristics of road dust emissions, the effects of temperature, humidity, and wind speed on road dust, as well as the correlation between road and high-space particulate matter concentrations. A section of a real road in Jinhua City, South China, was chosen for the study. The findings demonstrate that the concentration of road dust particles has a very clear bimodal single-valley distribution throughout the day, peaking between 8:00 and 11:00 and 19:00 and 21:00 and troughing between 14:00 and 16:00. Throughout the year, there is a noticeable seasonal change in the concentration of road dust particles, with the highest concentration in the winter and the lowest in the summer. Simultaneously, it has been discovered that temperature and wind speed have the most effects on particle concentration. The concentration of road dust particles reduces with increasing temperature and wind speed. The particle concentrations of road particles and those from urban environmental monitoring stations have a strong correlation, although the trend in the former is not entirely consistent, and the changes in the former occur approximately 1 h after the changes in the latter.

Effects of spherical fillers reinforcement on the efficacy of thermal conductivity in epoxy and polyester matrices: Experimental validation and prediction using finite element method

AbstractThe creation of a theoretical heat conduction model for polymers embedded with spherical inclusions is described in this study. It also contains the experimental confirmation of the suggested correlation for utilizing the model to estimate the effective thermal conductivity (K) of such composites. According to ASTM‐E‐1530, composites are made with varying amounts of aluminium oxide and pine wood dust reinforced in polyester resin. The effective thermal conductivities (Keff) of the composites are then determined using the Unitherm TM model 2022. Ansys 19.R2 software is used to evaluate the effective thermal conductivity of these composites with a uniform filler distribution, while Digimat‐FE software is used determine the thermal conductivity values of such particle filled polymer composites with a random filler distribution. After comparison and validation with experimental data, these values are shown to be fairly good agreement with the theoretical values from the suggested correlation. The investigation is further expanded to determine the thermal conductivities for epoxy composites using wood apple shell dust and coir dust particle. Also epoxy and polyester composites reinforced with SiO2 and TiO2 have been investigated in the similar manner. The main thrust of this report to validate the numerical results of composites by varying numerous polymers. The thermal conductivity all the composites grow monotonically with increase in filler content. The thermal conductivity of silicon dioxide, titanium oxide, and aluminium oxide filled epoxy composites is measured as 1.5, 7, and 35 W/m‐K respectively.Highlights In this study spherical fillers are successfully used as a potential filler material in polyester composites The thermal conductivity predicted by proposed mathematical model of polyester is validated with measured value and found better agreement. The Ansys 19.R2 and digimat software are used to predict the thermal conductivity values of these composites. The mathematical model is further used to predict thermal conductivity of epoxy composites to check the accuracy of the model.

Experimental study of discharge current oscillations with dust particles

We present a detailed experimental study of discharge current oscillations in a planar cathode plasma with poly-dispersed alumina dust particles. The dominant frequency of oscillation depends on the discharge voltage, operating pressure, and amount of dust particles placed on the cathode. The power-law variation in the dominant frequency with different external operating parameters is presented. Experimental observations suggest that the dominant mechanism behind the generation of these oscillations is the cathode spot injection of sub-micron-sized dust particles. The cathode spots also aid in the generation of fine dust particles. The threshold limit on dust particle density dispersed on the cathode suggests that below the threshold limit, the fine particles depleting the electrons play an important role and lead to the generation of self-excited oscillations. Operating above the threshold limit, a stable dust cloud was observed together with the suppression of self-excited oscillations.

Reactive Molecular Dynamics Simulations of Micrometeoroid Bombardment for Space Weathering of Asteroid (162173) Ryugu

Remote sensing observations by Hayabusa2 and laboratory measurements have revealed that the phyllosilicates on asteroid (162173) Ryugu are dehydrated/dehydroxylated due to space weathering. Reactive molecular dynamics simulations were performed to evaluate the magnitude of the dehydroxylation of Mg-rich serpentine by micrometeoroid impacts. When micrometeoroids were not coupled with interplanetary magnetic fields, serpentine could be dehydroxylated by micrometeoroids as small as 2 nm in size. In particular, ∼200 O–H bonds dissociated when the meteoroids were derived from cometary activity (the impact velocity was ∼20 km s−1). When nano-sized dust particles were accelerated to ∼300 km s−1 by the magnetic fields of solar wind plasma, the number of dissociated O–H bonds increased by 1 order of magnitude. Consequently, even 1 nm-sized dust particles can contribute to the space weathering of Ryugu. In all cases, Si–OH, H2O, and free OH were generated from the hydroxyls initially connected to Mg, which could partially offset dehydration. Despite the limitations of our computational resources, which restricted the simulation timescale to 1 ps, reactive molecular dynamic simulations demonstrated that micrometeoroid bombardment could influence the space weathering of asteroids.

Development and application of diffusive gradients in thin-films for in-situ monitoring of 6PPD-Quinone in urban waters

The occurrence and risk of N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine-quinone (6PPD-Q), derived from the oxidation of the tire antidegradant 6PPD, has raised significant concern since it was found to cause acute mortality in coho salmon when exposed to urban runoff. Given the short half-life period and low solubility of 6PPD-Q, reliable in situ measurement techniques are required to accurately understand its occurrence and behaviour in aquatic environments. Here, using the diffusive gradients in thin-films (DGT) method with HLB as a binding agent, we developed a new methodology to measure 6PPD-Q in urban waters. 6PPD-Q was rapidly and strongly adsorbed on the HLB-binding gel and was efficiently extracted using organic solvents. The HLB-DGT accumulated 6PPD-Q linearly for >7 d and its performance was not significantly affected by pH (6.5–8.5), ionic strength (0.0001–0.5 M) or dissolved organic matter (0–20 mg L−1). Field evaluation of the DGT method demonstrated its effectiveness in urban runoff, detecting 6PPD-Q levels of 15.8–39.5 ng L−1 in rivers. In snowmelt, DGT detected 6PPD-Q levels of 210 ng L−1 which is two times higher than the value obtained by grab sampling. 6PPD-Q levels were much higher in snowmelt than those in rivers. This indicates that snowfall constitutes an important transport pathway for 6PPD-Q and that DGT effectively captured the fraction continuously released from dust particles in the snow samples. 6PPD-Q posed a substantial risk to migratory fish in urban waters, and its release from tire wear particles requires further investigation. This study is the first to develop a DGT-based in situ measurement method for 6PPD-Q in urban waters, and the method can ensure an accurate measurement of the release of 6PPD-Q to the environment, particularly in rainfall or snowmelt, important pathways for its entry into the aquatic environment.

Optimization of the intake system for the Setra NS 913 bus

Abstract The paper presents the implementation on buses of a dynamic air transfer system (SDTA) brand Air by Corneliu. That system is the subject of a patent entitled Dynamic Air Transfer Device RO 200900028. At the initiative of the Alba Iulia public Transport society, with a fleet of about 100 buses, we started a study on the efficiency of air intake in the internal combustion engine by implementing an SDTA. Since the air filter location on this bus model, Setra NS 913, is behind the rear axle wheels, the filter is exposed to dust, water and other particles thrown by the drive wheels, which leads to premature clogging and blockage of the filtration area, in the context in which the bus runs mainly on asphalt-free roads. The gas-dynamic resistance (filter permissiveness) would increase considerably, resulting in a severe reduction in the degree of filling of the engine cylinders. In order to eliminate the disadvantages mentioned above, respectively to increase the life of the air filter with implications on the performance of the engine, we have designed a dynamic system consisting of the following components: the air collector, located on the top of the bus; the grid housing, located on the suction grid; tubing, connecting element between the air collector and the grid housing. In order to realize the 3D model of SDTA, the specialized software VISI - CAD / CAM was used.

Monitoring and control of air filtration systems: Digital twin based on 1D computational fluid dynamics simulation and experimental data

This study presents the development of a digital model based on one-dimensional computational fluid dynamics for the monitoring and control of filtering systems used for removing flour, dust, and other particulates from the airflow arriving from various sections of industrial production plants.Focusing on a pilot plant equipped with a cyclone bag filter, historical experimental data was integrated with the results of a one-dimensional fluid dynamics simulation model to create a digital twin capable of real-time control and regulation of industrial plants. In particular, measured pressure drop data under different clogging conditions were interpolated to generate the characteristic curves of the filter under various clogging conditions, to be implemented within the digital model of the plant. The generated model, validated through a dedicated experimental campaign, accurately predicted the airflow rate and pressure distribution across the plant. The system’s capability to adapt to changing operational conditions, such as clogging, was demonstrated through simulation, highlighting the model’s utility in maintaining the desired operation levels while minimizing the need for extensive sensor networks.The analyzed case study in the field of air filtration systems aims to fill the gap in the scientific literature related to the application of Digital Twin technology to the control of industrial manufacturing plants. The findings highlight the potential of digital twins in monitoring and control, as well as predictive maintenance, of industrial systems. The findings highlight the potential of Digital Twins in monitoring and control, as well as predictive maintenance, of industrial systems. Future research activities will explore the model’s applicability in failure and anomaly detection, to further enhance predictive maintenance of air filtering systems.

Effect of Dust Particles in Soliton Reflection in the Presence of Trapped Electrons in an Inhomogeneous Plasma

Effect of Dust Particles in Soliton Reflection in the Presence of Trapped Electrons in an Inhomogeneous Plasma

Consequence of Cattaneo-Christov heat and mass flux models on bioconvective flow of dusty hybrid nanofluid over a Riga plate in the presence of gyrotactic microorganisms and Stephan blowing impacts

This study investigates the impact of the Stephan blowing and Cattaneo-Christov flux model on bioconvective flow of dusty hybrid nanofluid over a Riga plate in the presence of gyrotactic microorganisms and variable dust particles volume friction. Mass and heat phenomena are explored in the context of Stefan blowing impacts. The hybrid nanofluid consists of nanoparticles of MgO and Ag base fluid water. The Cattaneo-Christov mass and heat flux model has a significant impact on the bioconvective flow. The model predicts a slower temperature distribution and a higher concentration gradient than the traditional Fick's law and Fourier's law, respectively. The occurrence of gyrotactic microorganisms enhance the flow characteristics. This model is important for optimizing mass and heat transfer in a variety of engineering systems, including heating and cooling technologies, where effective thermal control is essential. It can be used by employing the regulated migration of microbes. By maximizing the removal of impurities, it helps with the design of sophisticated water purification systems in environmental engineering. The amalgamation of gyrotactic microorganisms and Stefan blowing effects augments the comprehension of intricate fluid dynamics, maybe resulting in advancements in microfluidic apparatuses and bio-inspired technologies. In order to transform the controlling PDEs into nonlinear ODEs, a new set of non-dimensional variables is used. The MATLAB (RKF-45th) technique is then used to resolve the ODEs numerically. As the Stephan blowing parameter (0.1≤Sb≤1.9) increases, the outcomes show that the flow distributions upsurge for both the dust and fluid phases, but the dust and fluid phase thermal distributions drop.

Direct in-scope suction: an in vitro evaluation of a single use flexible ureteroscope with integrated suction capability.

To evaluate the stone clearance rate and limitations of a novel integrated suction capability within a single-use flexible ureteroscope according to stone particle size. Varying sized stone particles were created using a stone phantom (Begostone Plus, Bego ©, Lincoln, RI, USA). Particle size ranged as follows: 63-125µm, 125-250µm, 250-500µm, 500µm- 1mm and 1-2mm. These were mixed with Normal saline (0.9%) to mimic in vivo conditions. The suction enabled single-use flexible ureteroscope (Pusen, Zhuhai, China) was used to aspirate stone fragments in three trials. Firstly, aspiration of 5g of each dust range was attempted. Secondly, a direct comparison of the integrated suction to a manual syringe technique was applied to 1g of each size range. Finally, aspiration was applied to 5g of a heterogenous 1:1:1:1:1 mixture. Endoscopic clearance rate (g/min) and number of blockages were recorded. Each challenge was repeated three times. The integrated suction cleared 100% of dust < 250µm. Endoscopic clearance rates were significantly faster than manual aspiration (3.01g/min versus 0.41g/min) for dust between 125 and 250µm (p = 0.008). Complete endoscopic clearance by 180s (without encountering test limiting blockages) was unsuccessful for particles > 250µm. Clearance rates were greatly limited by stone particle size heterogeneity above 250µm, to 0.09g/min. This technology works better in vitro than previously DISS evaluated methods when challenged by stone dust < 250µm. However, this adaptation is significantly challenged in the presence of stone dust particles > 250µm.

Antimoniosis: Radiological Insights into a Rare Pneumoconiosis in Miners.

Pneumoconiosis describes diseases caused by the accumulation of inorganic dust particles in the lungs, leading to tissue damage. The diagnosis relies on a history of exposure and compatible radiological findings. We aimed to investigate the radiological findings in individuals exposed to antimony-inert dust relative to their working periods. Fifty-six symptomatic male antimony miners were retrospectively evaluated for demographics and chest computed tomography (CT) scans. The demographic and radiological data of patients with a history of antimony mining, who presented at our pulmonary clinic between June 2017 and June 2023, were analyzed according to the duration of exposure. The study included 56 male patients with a mean age of 58.5±13.02 years and a mean exposure duration of 13.63 ± 6.82 years. CT scans showed that 73.2% (n=41) had upper and middle lung zone involvement, and 55.4% (n=31) had extensive involvement. Micronodules with centriacinar ground-glass opacities were the most common finding (n=37, 66.1%), followed by nodular opacities with irregular margins (n=22, 39.3%) and solid micronodules (n=20, 35.7%). Patients with over 20 years of exposure had significantly higher rates of respiratory and cardiovascular disease (p<0.05). Increased exposure time correlated with more extensive parenchymal involvement and higher rates of calcification in mediastinal lymph nodes, solid micronodules, nodular opacities with irregular margins, honeycombing, and conglomerate mass appearance. Radiological findings in pneumoconiosis generally worsen with longer exposure. Given the scarcity of up-to-date information on antimony pneumoconiosis, further studies focusing on radiological findings and chemical analyses of those exposed to antimony mine dust are essential to identify related pathologies.

Self-Oxidation of the Atmospheres of Rocky Planets with Implications for the Origin of Life.

Rocky planets may acquire a primordial atmosphere by the outgassing of volatiles from their magma ocean. The distribution of O between H2O, CO, and CO2 in chemical equilibrium subsequently changes significantly with decreasing temperature. We consider here two chemical models: one where CH4 and NH3 are assumed to be irrevocably destroyed by photolysis and second where these molecules persist. In the first case, we show that CO cannot coexist with H2O, since CO oxidizes at low temperatures to form CO2 and H2. In both cases, H escapes from the thermosphere within a few 10 million years by absorption of stellar XUV radiation. This escape drives an atmospheric self-oxidation process, whereby rocky planet atmospheres become dominated by CO2 and H2O regardless of their initial oxidation state at outgassing. HCN is considered a potential precursor of prebiotic compounds and RNA. Oxidizing atmospheres are inefficient at producing HCN by lightning. Alternatively, we have demonstrated that lightning-produced NO, which dissolves as nitrate in oceans, and interplanetary dust particles may be the main sources of fixed nitrogen in emerging biospheres. Our results highlight the need for origin-of-life scenarios where the first metabolism fixes its C from CO2, rather than from HCN and CO.

Environmental risk estimation of potentially toxic metal(loid)s (PTMs) in fine particulate dust on the surface of children's playgrounds in parks

To determine the priority control factors for risk control and management of potentially toxic metal(loid)s (PTMs) in fine particulate dust (FPD) on the surface of children's playgrounds in parks, a comprehensive study was conducted on the pollution, risks, and sources of 12 PTMs in the FPD, taking Xi’an, China as a case. The pollution, ecological and health risks of PTMs were assessed using Nemerow integrated enrichment factor, modified Nemerow integrated eco–risk index, and health risk evaluation model, combined with Monte Carlo simulation. The sources of PTMs in the FPD were quantitatively apportioned using a positive matrix factorization model. Priority control factors for PTMs risk control and management were determined based on the results of source–oriented pollution and risk assessment. The results showed that the average contents (mg kg–1) of Cd (1.9), Cr (99.8), Cu (96.3), Hg (0.2), Pb (61.1), and Zn (239.4) in the FPD were considerably greater than local background values. The sources of PTMs in the FPD are industrial emission, coal combustion and medical activities, mixed source, and natural source, contributing 24.7%, 18.2%, 35.1%, and 22.1% to the total content of PTMs in the FPD, respectively. PTMs in the FPD posed a certain cancer risk to the elderly and children. Industrial emissions and mixed sources are priority control sources, while Cd and Cr are priority PTMs. It is recommended that local eco–environmental departments strengthen environmental monitoring of playgrounds, as well as management of industrial and transportation emissions, to ensure the health of residents.

Effect of airflow velocity in vessel-pipelines on dust explosion during pneumatic conveying

In order to investigate the flame propagation and pressure characteristics of dust particles during airflow transportation, a dust explosion experimental apparatus simulating dust handling processes was designed. The system is supplied with a stable airflow by a high-pressure fan, capable of continuously transferring dust from the vessel to the pipeline at a controllable speed. Dust explosion experiments were meticulously executed by applying 1 kJ of ignition energy to the transported dust particles at airflow velocities of 5, 10, and 15 m/s. This study examines the effects of airflow velocity, pipe diameter, and ignition position on explosion characteristics and delves into the mechanisms of these effects through a detailed analysis of experimental results. For the maximum explosion pressure, an increase in airflow velocity causes the maximum explosion pressure to rise. As the pipe diameter increases, the maximum explosion pressure first rises and then falls. The maximum explosion pressure occurs in the case of bottom ignition. The range of maximum explosion pressure values is expected to provide a reference for explosion detection and explosion venting. For flame propagation, the flame undergoes five processes within the vessel, including ignition of dust particles, spherical flame development, flame stretching towards the mouth of the pipe, complete combustion of particles, and near exhaustion of particle combustion. The higher the airflow velocity and the larger the pipe diameter, the more pronounced the flame stretching and development towards the pipe opening become. Within the pipe, two distinct flame propagation behaviors were observed under conditions of high and low airflow velocities. Compared with the experimental results of high-pressure pneumatic powder spraying forming a dust cloud within a vessel-pipeline, this study measures the maximum explosion pressure at specific turbulence levels and establishes a quantitative relationship between airflow velocity and explosion characteristics. Utilizing this correlation can provide a reference for predicting industrial-grade dust explosion characteristics at different airflow velocity levels, thereby offering a more optimized design basis for the design and safety protection of industrial equipment.

The Effect Of Pm2.5 Dust Exposure On Mda And 8-Ohdg Urine as an Oxidative Stress Indication Of Brick Workers in Mojokerto District, 2024

Exposure to PM2.5 dust could enter the human body through inhalation and have a negative impact on health through the mechanism of the formation of reactive oxygen species (ROS) in the respiratory tract, where the remaining ROS could burn cell nuclei and produce a byproduct in the form of malondialdehyde (MDA). In addition, oxygen radicals that could enter cells could burn DNA and produce 8-hydroxy-2'-deoxyguanosine (8-OHdG). High levels of MDA and 8-OHdG in the body reflect high levels of oxidative stress. Analyze sis influence on pap a ran PM 2.5 was an indication of oxidative stress through examination of urine MDA and 8-OHdG levels in brick-making workers in Mojokerto. Regency This type of research was observational and analytical, with a cross-sectional approach. There was an influence of exposure to PM 2.5 dust particles on MDA and 8-OHdG levels. MDA and 8-OHdG levels in the urine of workers at exposed locations were higher compared to workers at unexposed locations. The oxidative stress of workers in exposed locations was higher than that of workers in unexposed locations.

Per- and polyfluoroalkyl substances (PFAS) in Indian environment: Prevalence, impacts and solutions

Per- and polyfluoroalkyl substances (PFAS) pose a significant and growing environmental challenge worldwide due to their remarkable persistence, widespread presence, and potential to adversely affect human health. This review offers a holistic investigation of current knowledge regarding PFAS in India. Existing research demonstrates the presence of PFAS in various environmental compartments, including water bodies, soil/sediment, atmosphere, and even wildlife. Furthermore, the review explores the potential ecological and human exposure pathways. Some of these pathways include consumption of contaminated drinking water, PFAS-laden food, and inhalation of dust particles containing PFAS. The potential health impacts on humans and biota are then elaborated, highlighting developmental problems, endocrine disruption, and even an increased risk of certain cancers. The findings strongly suggest that industrial activity, urbanization, and consumer product usage are significant contributors to environmental PFAS contamination. A critical gap identified within this review is the absence of established regulations for PFAS usage and disposal within the Indian environment. The review summarizes existing remediation techniques, providing a comprehensive strategy for managing PFAS in the Indian context. The implementation of stringent regulations governing PFAS production, use, and environmental discharge, coupled with the exploration of non-fluorinated alternatives, is imperative. Additionally, the deployment of advanced water treatment technologies specifically designed for PFAS removal and the fostering of collaborative research and development efforts are crucial steps towards mitigating PFAS contamination. In conclusion, this review emphasizes the urgent need for a multifaceted approach to manage PFAS in India.

Influence of radiation and thermal slip on electrically conductive dusty Walter’s B fluid moving peristaltically through an asymmetric channel

MotivationThe motivation of this recent article is to study dusty Walter’s B fluid flow due to its wide range of applications in biology and polymer industry. The fluid is traveling peristaltically through an asymmetric channel with wall slip. A discussion is also presented to examine heat transfer effects with thermal radiation and slip. MethodologyThe regular perturbation technique is employed to evaluate the mathematical model of the problem, which is first simplified by using stream functions. Mathematical results are simulated to illustrate flow characteristics of fluid and solid particles in salient quantities. Also, graphs of temperature distribution of fluid and dust particles have been discussed to study the impacts of various parameters. OutcomesWalter’s B fluid parameter reduces speed of both fluid and dust particles. By increasing thermal slip parameter, temperature transference becomes slower through the fluid, while Brinkman number significantly raises the temperature profile of both fluid and particles. This article presents a theoretical analysis of the problem. Moreover, the characteristics of liquids involved in the plastic industry and medical science can also be understood using the current analysis. Originality/ValueWalter’s B fluid with dust particle suspension has not been investigated for slip and thermal radiation effects.

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.

Self-ignition behaviour of corn cob, wheat bran and rice husk residues in ambient air from biomass gasification

The possibility of different agrowastes to self-ignite under ambient condition, due to exothermic reactions between their surface molecules and air or other oxidizing agents which are conveyed into the void volume between the particles, exists. It is imperative to investigate the self-ignition ability of these harzadous waste products causing environmental pollution after the milling process to avoid sudden fire outbreaks. In this study, the self-ignition attributes of corn cob, wheat bran and rice husk residues in ambient air from biomass gasification was investigated by evaluating their self-ignition temperatures using DIN EN 15188:2021 standard and Frank-Kamenetzkii's theory of thermal explosion at varying basket volume. The results revealed decrease in the ignition temperature of dust samples as ignition time and dust basket volume were increased. Sample C (rice husk dust residue) was considered to be the most hazardous with respect to its propensity to self-heating possessing the lowest self-ignition temperature of 173 °C at 800 mL cubic mesh. Its moisture content and activation energy of 1.41 % and 46.52 kJ/mol respectively were the lowest. Its thermal conductivity, carbon content, heating value and bulk density of 0.07 W/mK, 78.98 wt%, 26,895 kJ/kg and 255.4 kg/m3 respectively were the highest. Correlation coefficient from the Arrhenius plot showing the self-ignition behaviour of dust samples using the model of Frank-Kamenetzkii were 0.9976, 0.9910 and 0.9962 for corn cob, wheat bran and rice husk residues respectively. In conclusion, the data presented are effective in predicting the self-ignition ability of corn cob, wheat bran and rice husk residues in ambient air from biomass gasification in order to prevent sudden fire attack that may arise based on storage of their dust particles in food processing industries.

Effect of large particle mixing on cloud ignition and explosion of fine rice husk

Large particles mixed with fine dust are commonly found in the processing and transportation of grain dust. The mixture of dust is exposed to the risk of dust explosions when suspended in the environment. Using a 20 L spherical explosion device and the dust cloud minimum ignition energy (MIE) experimental platform, this study examines the effects of crushed brown rice mixture on the ignition and explosion of fine rice husk dust. The discovery of large granules of crushed brown rice being lifted up to form flow "obstacles" in the mixed dust cloud has a similar inhibitory effect to inert materials, causing the MIE of the dust cloud to increase from 40 mJ to 150 mJ. However, 5 % of crushed brown rice will lower the 10 mJ dust cloud's ignition energy when the concentration of dust clouds is 500 g/m3. Through testing the dispersibility of mixed dust clouds, it was found that fine dust particles adsorbed on the surface of large particles will peel off after being lifted, improving the dispersibility of the mixed dust cloud and forming a system of mixed dust clouds with finer effective particle size, thereby promoting ignition. Furthermore, due to the improvement in the dispersibility of mixed dust clouds by large particles, at mixing ratios below 30 %, large particles will also significantly increase the maximum rate of pressure rise (dP/dt)max, increasing the likelihood of dust ignition and the consequences of an explosion. Therefore, these findings should be taken into consideration during the process of grain processing and transportation.