Dust Ratio Research Articles

Classification of aerosol types using AERONET version 3 data over Kuwait City

The particle linear depolarization ratio (PLDR) and single scattering albedo (SSA) at 1020 nm are retrieved by the AERONET (Aerosol Robotic Network) Version 3.0 level 1.5 inversion products are used to categorize different types of aerosols and investigate their temporal distribution for the atmospheric particles of Kuwait City. The results show that when PLDR increases in the atmosphere, the amount of SSA at 440, 670, 870, and 1020 nm wavelength channels and the contribution of coarse-mode particles increased. Also, the spectral behavior of SSA changes from a negative to positive slope by increasing PLDR. The highest density of aerosol incidence rate in the two-dimensional histogram diagram occurs in the range with low fine mode fraction and dust ratio. The main objective of this study is to present that the atmosphere of Kuwait City is strongly affected by pure dust (PD) and polluted dust plumes, namely, dust-dominated mixture (DDM), pollution dominated mixture (PDM), all with an occurrence frequency of 85%. The annual average incidence rate of different aerosol types is 32.2% for DDM, 31% for PD, 21.8% for PDM, 10.3% for SA, 2.5% for MA, 1.3% for WA, and 0.9% for NA, from 2006 to 2019. However, the distribution of different types of pollution particles varies with the seasons change. The incidence rate of pure and polluted dust is more than 85% from March to October. In addition, the annual average incidence rate of dust-free pollution aerosols (NA, WA, MA, and SA) is 15%. The highest amount of dust-free pollution particles in different months is related to the SA that constitutes about 40% in the cold months.

Ocean Dust Deposition Rates Constrained in a Data‐Assimilation Model of the Marine Aluminum Cycle

AbstractAluminum (Al) is delivered to surface ocean waters by aeolian dust, making it a promising tracer to constrain dust deposition rates and the atmospheric supply of trace metal micronutrients. Over recent years, dissolved Al has been mapped along the GEOTRACES transects, providing unparalleled coverage of the world ocean. However, inferring atmospheric input rates from these observations is complicated by a suite of additional processes that influence the Al distribution, including reversible particle scavenging, biological uptake by diatoms, hydrothermal sources, sediment resuspension. Here we employ a data‐assimilation model of the oceanic Al cycle that explicitly accounts for these processes, allowing the atmospheric signal to be extracted. We conduct an ensemble of model optimizations that test different dust deposition distributions and consider spatial variations in Al solubility, thereby inferring the atmospheric Al supply that is most consistent with GEOTRACES observations. We find that 37.2 ± 11.0 Gmol/yr of soluble Al is added to the global ocean, dominated in the Atlantic Ocean, and that Al fractional solubility varies strongly as a function of atmospheric dust concentration. Our model also suggests that 6.1 ± 2.4 Gmol Al/yr is injected from hydrothermal vents, and that vertical Al redistribution through the water column is dominated by abiotic reversible scavenging rather than uptake by diatoms. Our results have important implications for the oceanic iron (Fe) budget: based on the soluble Fe:Al ratio of dust, we infer that aeolian Fe inputs lie between 3.82 and 9.25 Gmol/yr globally, and fall short of the biological Fe demand in most ocean regions.

Research on dust control of mobile straw granulator

High particle concentrations, large sizes and coupled flows areproduced in mobile straw granulators during operation. To control the dust emissions and reduce the mass ratio of the dust into the press device of the granulator, an Eulerian multiphase flow model was first used to analyze the effects of the storage cage structure, flow velocity at the duct outlet, ambient wind speed and particle size on dust emissions. The flow characteristics of the particle distribution, particle trajectory and particle concentration were studied and verified by experiments. Second, a diversion duct was designed to reduce the phenomenon of dust emission and sedimentation by using the principle of gravity settlement. The results showed that the structure of the diversion duct and dense storage cage could improve the flow characteristics at the outlet, change the coupled effect between flow and particles, and play a key role in reducing dust concentration. The diffusion distance of dust emission could be restrained, and the mass ratio of dust entering the press device could be increased by reducing the outlet wind speed. When the air flow velocity at the duct outlet was reduced from 7.5 to 2.9 m∙s−1, the horizontal dispersion distance of dust was reduced to 4.33 m, and the mass of dust entering the press device accounted for approximately 60%. The difference in diffusion distance between particles with diameters of 30 and 5 μm was only 0.47 m, and the particle size had little effect on the dust emission distance. The spread of dust emissions could be inhibited in breezy and calm weather. The results provide a reference for the modification of farm equipment.

Fines content, plasticity index and dust ratio influencing the modulus and permanent deformation behavior of aggregates

Resilient modulus (Mr) and permanent deformation (PD) characteristics of unbound aggregates under repetitive traffic loads dictate the structural response and performance of pavement base and subbase layers. Aggregate material behavior is dependent on the amount of fines in particulate matrix, also referred to as fines content (percent passing number 200 sieve), as well as plasticity index, dust ratio (percent passing number 200 sieve to percent passing number 40 sieve), material type, aggregate gradation/packing and the interactions of these properties with each other. In this study, repeated load triaxial tests were conducted on crushed limestone and crushed gravel aggregates. Fines content and plasticity index were varied from 5% to 12% and 5% to 9%, respectively. Two most typical gradations of aggregates used in roadway construction in Illinois were utilized with dust ratios ranging from 0.4 to 1.0. The results of these tests were analyzed using the shakedown theory for evaluating typical base/subbase permanent deformation or rutting trends linked to practical design considerations. Charts were also established for the modulus and deformation characteristics of unbound aggregates to designate the material quality with performance trends. Such guiding charts were compared with others developed in previous studies by authors for determining aggregate behavior under monotonic loading tests such as California Bearing Ratio (CBR). The comparisons provide valuable insights on how each aggregate property influences strength, modulus and permanent deformation behavior under different loading conditions.

Improvement of traditional clay bricks’ thermal insulation characteristics by using waste materials

This study aims to improve clay bricks' thermal insulation properties by using waste materials. Laboratory scale samples were produced by an extrusion process, which simulates a feasible industrial production technique. The study results reveal that the unit weight of brick was reduced, and thermal properties were improved by introducing grapevine twig and poplar dust by forming pores in the brick mud after firing. When the substitution ratio of waste materials increased from 2.5 %–15 % by volume gradually, it was determined that the thermal conductivity coefficient (λ), dry bulk specific gravity, and compressive strength value of the clay brick decreased. However, the moisture content for extrusion and the water absorption ratio increased. The amount of waste material in clay brick mud was optimized, and the effect of these waste materials on the plastic and hardened properties of clay bricks were investigated. As a result, the optimum mix ratio of grapevine twig and poplar dust was 7.5 % by volume considering extrudability, physical, thermal and mechanical properties of the final product. It was shown that the bricks' weight was reduced by 25 %, and the thermal conductivity coefficient was decreased by 22 % at a 7.5 % substitution ratio by volume, respectively. With the addition of waste materials, drying shrinkage values decreased due to waste materials restricting effect, while firing shrinkage values increased due to increased porosity. Moreover, it was determined that these two waste materials could be used at similar dosages because they have introduced similar characteristics to traditional clay bricks.

Three-Year Investigation of Tillage Management on the Soil Physical Environment, Earthworm Populations and Crop Yields in Croatia

The aim of this study was to determine the environmental suitability of conservation tillage systems. A 3-year experiment was conducted in Croatia, to study the effects of different tillage treatments on soil properties, with the following: deep (DC), shallow tine cultivation (SC) and ploughing (P). Soil penetration resistance (SPR) was significantly greater in P compared to DC in all three years. In 2016, it was found at 30–40 and 40–50 cm; in 2017 at 10–20 cm; in 2018 at 0–10 and 10–20 cm. However, SC was significantly greater at 20–30, 30–40 and 40–50 cm compared to P and DC in 2017. The greater surface coverage in DC and SC (>30%) as compared to P (<1%) provided significantly higher soil moisture content (SMC) in maize (2016) and soybean (2018). In 2017, SMC in SC was significantly lower than in P and DC. Regarding all the 3 years, the agronomic structure in DC and SC had significantly greater crumb ratio compared to P, whereas P had significantly higher dust ratio than DC and SC. Throughout the 15 measurements, DC provided the most favorable soil habitat (11 occasions out of 15). In 2017, the earthworm abundance was significantly higher in DC compared to SC. In all the three years, DC resulted the highest yield, however the difference was not significant. Higher surface coverage and SMC positively impacted the ratio of agronomic structure (decreased dust and increased crumb ratio) and earthworm abundance. It can be concluded that DC and SC provided greater soil coverage which positively affected SPR, SMC, agronomic structure and earthworm abundance as compared to P.

Electrical and Mechanical Effects of Carbon Powder in F and C Class Fly Ash Reinforced Mortars

This study was carried out to investigate the effects of carbon powder on the electrical conductivity and mechanical properties of fly ash reinforced mortars used as mineral additives. Samples were created by replacing CEM I 42.5 R cement, water and Cen standard sand with 0.5%, 1%, 3% carbon powder by weight. Class F and Class C fly ash were added separately at the rate of 10% and 20% by weight of cement to the formed carbon dust series. 20 different series were created with the reference sample. Electrical resistivity measurements were made to the oven dry and natural humid conditions of the samples that completed their 7,28 and 56 days curing period. The physical properties of the samples were determined and bending and compressive strength tests were made. The results obtained were evaluated and it was observed that with the increase of the carbon dust ratio compared to the reference sample, the electrical conductivity ratio increased, but the conductivity decreased depending on the time. It has been observed that the F class fly ash combination series are more conductive than the C class combination series. It was observed that the compressive and tensile strength values ​​of F and C class fly ash carbon dust free samples increased with time. Carbon dust has been shown to increase compressive strength in fly ashless series. There was an increase in the 56th day reading in the tensile strength. It was observed that F class increased tensile and compressive strength in fly ash and carbon dust combination series. Keywords: Carbon dust, F class fly ash, C class fly ash, Electrical conductivity. DOI: 10.7176/CER/13-2-02 Publication date: April 30 th 2021

Thermodynamic simulation of complex Pb−Bi concentrate oxidative bath smelting process

Abstract The element partitioning in a Pb−Bi concentrate oxygen-rich bath smelting process was studied using thermodynamic equilibrium simulation method. Effects of oxygen to feed ratio (OFR) and sulfur dioxide partial pressure (pSO2) on the partitionings of Bi, Pb, As, Sb, Cu and Ag were analyzed and compared with industrial data. The results suggested that the optimal OFR was between 6.3 and 6.8 kmol/t to maximize Bi, Pb, Cu and Ag partitioning in the metal phase. Further increase of OFR led to the drop of metal partitioning and increase of slag liquidus temperature. High pSO2 led to high deportment of Bi and Pb in the gas phase mainly in the form of sulfides, suggesting that a low pSO2 was conducive for reducing the dust ratio.

Removal process and mechanism of lead in Zn-containing rotary hearth furnace dust

To deal with the removal of PbO2 during the purification process of the Zn-containing rotary hearth furnace (RHF) dust, this study adopts a choline chloride-urea (ChCl-urea) based deep eutectic solvent system and water-washed Zn-containing RHF dust as the main target of investigations, preparing ZnO nanoparticles using a Zn-induced PbO2 removal and thermal treatment of the precursor. The effects of the mass ratio of Zn particles and Zn dust (maked as Zn particles - Zn dust), reaction temperature, and reaction time on the removal of PbO2 were also investigated. The ZnO nanoparticles and the PbO2-removed products were characterized by X-ray diffractometry, X-ray fluorescence spectroscopy, scanning and transmission electron microscopy. The results showed that the optimal conditions for efficient removal of PbO2 included the reaction temperature of 80 °C, The Zn particles - Zn dust is 1.6, with a reaction time of 3 h. The final product had a ZnO content of 98.332% with a particle size distribution in the range of 10–100 nm with an average diameter of 39 nm, belonging to the Category-II ZnO nanoparticles. The PbO2 removal mechanism mainly involved the dissolving of PbO2 in ChCl-urea, forming [Pb(ClO·urea)2]2−, and the replacement reaction between Zn particles and [Pb(ClO·urea)2]2−, producing metallic Pb and [ZnClO·urea]−.

Gypsum Boards Reinforced with Cotton Dust Fiber

This research was aimed to study the production of gypsum boards mixed with cotton dust fiber for construction purposes. The cotton dust fiber 5, 10, 15, and 20% by weight was mixed with gypsum plaster and cast in the size 300 × 400 × 9 cubic millimeters. The water content was added 77 % by weight of the mixture. The ultimate strength, modulus of rupture, and weight of the gypsum board were investigated. The results showed that the ultimate strength and modulus of rupture of the gypsum boards without cotton dust fiber were 168.78 Newton and 3.66 Mega Pascal, respectively, which met the criteria for standard gypsum board under TIS 219-2524. However, the ultimate strength and modulus of rupture of the gypsum board mixed with cotton dust fiber were lower than the standard gypsum board. The weight of the gypsum board was decreased when the cotton dust fiber content was increased. It was found that the appropriate ratio of gypsum plaster and cotton dust was 90:10 incorporated with 6 wt. % PVA. The ultimate strength and modulus of rupture of the appropriate gypsum board were 135.31 N and 3.13 MPa, which was the criteria standard gypsum board products (TIS. 219-2524). The weight of the appropriate gypsum board was lighter than the gypsum board without cotton dust fiber addition about 289.75 grams (21 percent). Therefore the gypsum board mixed with cotton dust fiber could be developed for the construction, ceiling, and wall.

A design of in-situ detector of charged lunar dust (DCLD)

Charged dust widely exists on the surface of the moon, which is considered to be closely related with many natural phenomena. China's Chang’E-5 lunar mission plans to monitor the charged characteristics of electrostatically levitated dust on the lunar surface in an economical and effective way. The designed detector consists of two probes, the reference probe and the measuring probe. Each single probe consists of two grids and a sticky quartz crystal microbalance. The sensitivity coefficient of measuring probe is SM=(8.002±0.510)×10−9g/Hz·cm2, and that of reference probe is SR=(9.137±0.369)×10−9 g/Hz·cm2 under the test. By comparing the measurement results of two sets of probes, the mass proportion of dust with different charge/mass ratio of suspended lunar dust can be obtained. These results measured on the lunar surface would be helpful for analyzing the levitation mechanisms and motion characteristics of lunar dust.

Physicomechanical properties of composite tiles produced from granite dusts and municipal wastes

The present economic use of wastes all over the world is to reduce the environmental pollution through waste recycling. This research sought to produce and study alternative form of recycling tree pruning and bamboo waste as partial substitute materials for granite dust in composite tiles. Composite tiles of 190 × 98 mm were produced from various ratios of granite dust, tree pruning and bamboo wastes using cement as a binder. The density, water absorption, flexural strength and compressive strength analyses were carried out on the composite tiles following different ISO standards. Thermal conductivity was done using an Armfield computer compatible linear heat conduction tester. The density and water absorption capacity of the composite tiles ranges from 0.70 to 1.89 g/cm3 and 8.25 to 97.71%, respectively. The results of this study also showed that the partial substitution of tree pruning and bamboo wastes for granite dust lowered the flexural and compressive strength of the composite tiles. The maximum flexural (1.53 MPa) and compressive strength (1.12 MPa) obtained were from sample produced from 70% granite and 10% tree pruning with 20% cement. The composite tiles have relatively low thermal conductivity that ranges from 0.02197 to 0.02213 W/m K. This makes it a suitable candidate for low load-bearing insulating construction material.

Physico-mechanical properties of cement bonded ceiling board developed from teak and African locust bean tree wood residue

Abstract Over the years, the pursuit for locally sourced economical and environmentally safe materials has been on the increase in the development of composite boards. These locally sourced materials are organic materials from plants and livestock such as wood residue, feathers, rice husk, maize husk and bamboo fiber. Therefore, this study utilizes species of wood residue in the development composite ceiling boards. Ceiling boards were developed from teak and African locust bean tree wood residue using cement as a binder. The ceiling boards were made by varying the composite mass of the mix and mixing ratio of wood dust to cement. A constant load of 5 kN was used for the compaction process using a hydraulic pressing machine. Physico-mechanical properties of the ceiling boards such as moisture content, density, water absorption, drying shrinkage, tensile strength, and compressive strength were evaluated. The percentage of moisture content were 9.50 and 14.50% for teak and African locust bean tree wood dust, respectively. The values of density varied from 0.56 − 0.68 g/cm3. The water absorption ranged from 9.0 to 39.8% after 24 h immersion and drying shrinkage ranged from 8.60 to 35%. The maximum impact energy obtained is 98 J. The highest tensile, compressive and flexural strengths for the ceiling boards were 1.09, 0.82, and 0.56 MPa, respectively. The composite samples showed that ceiling boards made from teak wood dust is most suitable for interior use. Cement was found to be suitable as a binder for the development of ceiling boards.

Determination of Soil, Litter Properties and Carbon Stock Capacities of Different Stand Types in Western Black Sea Region

The aim of the study is to reveal how some of the physical and chemical properties of the soil and litters in the Pinus nigra, Pinus sylvestris and Pinus sylvestris-Pinus nigra stand mixture and how the amount of carbon stored varies according to the tree type. In this context, soil samples were collected from two different levels, litter examples were collected from two different layers including leaf and fermentation+humus and undisturbed soil samples were collected from three different depths. pH, electrical conductivity, organic matter, texture, bulk density, carbon rate and carbon content values were determined in soil and litter samples. According to the soil samples analysis results, the highest ph (7.74), electrical conductivity (147.85 μs/cm), organic matter (3.03%), carbon ratio (1.76%), carbon amount (6.72 t/ha), clay (24.81%) and silt (11.49%) values were determined in Pinus sylvestris-Pinus nigra stand mixtures. The highest sand value (73,60%) in Pinus sylvestris and bulk density value (1.42 gr/cm³) in Pinus nigra has been identified. The average values of pH (6.93) and carbon ratio (30.38%) in litter samples were determined in the highest Pinus sylvestris-Pinus nigra stand mixtures. According to the statistical analysis, it was determined that there was no statistically significant difference (p>0.05) in carbon amount, dust ratio and bulk density values in soil samples. In other analyzes, it was determined that there were significant differences between the groups (p 0.05). Key Words: Litter, Soil, Carbon, Pinus sylvestris, Pinus nigra, Mixture stand DOI: 10.7176/JSTR/6-12-06

Experimental Research and Numerical Simulation of Ejector Precipitator in a Fully Mechanized Mining Face

In order to effectively reduce the coal dust concentration in a fully mechanized mining face, this research used laboratory experiment, numerical simulation, and field test to conduct an in-depth exploration of the ejector precipitator installed at the low-level caving coal hydraulic support. Firstly, through the experimental platform in the laboratory, the dust removal effect of the nozzle with different structural parameters was tested, and the 3D particle dynamic analyzer was adopted to verify its atomization characteristics; then, the structural parameters corresponding to the nozzle in the best test results were obtained. Secondly, by using Fluent, the negative pressure flow field in the ejector barrel was numerically simulated. The results indicated that when the pressure of supply water was 12 MPa, the negative pressure value formed in the flow field was the lowest and the inspiratory velocity was the largest, which was conducive to dust removal. Finally, the tests of liquid–gas ratio and dust removal ratio were carried out in a fully mechanized mining face. The results showed that when the nozzle specification recommended by the experiment and the pressure of supply water recommended by the numerical simulation were used, the removal ratios of the total coal dust and the respirable coal dust were 89.5% and 91.0%, respectively, at the measuring point of the highest coal dust concentration. It indicates that the ejector precipitator has a good application effect in reducing the coal dust concentration in a fully mechanized mining face and improving the work environment of coal mine workers.

Protostellar collapse: the conditions to form dust-rich protoplanetary disks

Context. Dust plays a key role during star, disk, and planet formation. Yet, its dynamics during the protostellar collapse remain a poorly investigated field. Recent studies seem to indicate that dust may decouple efficiently from the gas during these early stages. Aims. We aim to understand how much and in which regions dust grains concentrate during the early phases of the protostellar collapse, and to see how this depends on the properties of the initial cloud and of the solid particles. Methods. We used the multiple species dust dynamics MULTIGRAIN solver of the grid-based code RAMSES to perform various simulations of dusty collapses. We performed hydrodynamical and magnetohydrodynamical simulations where we varied the maximum size of the dust distribution, the thermal-to-gravitational energy ratio, and the magnetic properties of the cloud. We simulated the simultaneous evolution of ten neutral dust grain species with grain sizes varying from a few nanometers to a few hundreds of microns. Results. We obtain a significant decoupling between the gas and the dust for grains of typical sizes of a few tens of microns. This decoupling strongly depends on the thermal-to-gravitational energy ratio, the grain sizes, and the inclusion of a magnetic field. With a semi-analytic model calibrated on our results, we show that the dust ratio mostly varies exponentially with the initial Stokes number at a rate that depends on the local cloud properties. Conclusions. We find that larger grains tend to settle and drift efficiently in the first-core and in the newly formed disk. This can produce dust-to-gas ratios of several times the initial value. Dust concentrates in high-density regions (cores, disk, and pseudo-disk) and is depleted in low-density regions (envelope and outflows). The size at which grains decouple from the gas depends on the initial properties of the clouds. Since dust cannot necessarily be used as a proxy for gas during the collapse, we emphasize the necessity of including the treatment of its dynamics in protostellar collapse simulations.

The Power Spectra of Polarized, Dusty Filaments

Abstract We develop an analytic model for the power spectra of polarized filamentary structures as a way to study the Galactic polarization foreground to the cosmic microwave background. Our approach is akin to the cosmological halo-model framework, and reproduces the main features of the Planck 353 GHz power spectra. We model the foreground as randomly oriented, three-dimensional, spheroidal filaments, accounting for their projection onto the sky. The main tunable parameters are the distribution of filament sizes, the physical aspect ratio of filaments, and the dispersion of the filament axis around the local magnetic field direction. The abundance and properties of filaments as a function of size determine the slopes of the foreground power spectra, as we show via scaling arguments. The filament aspect ratio determines the ratio of B-mode power to E-mode power, and specifically reproduces the Planck-observed dust ratio of one-half when the short axis is roughly one-fourth the length of the long axis. Filament misalignment to the local magnetic field determines the TE cross-correlation, and to reproduce Planck measurements we need a (three-dimensional) misalignment angle with an rms dispersion of about 50°. These parameters are not sensitive to the particular filament density profile. By artificially skewing the distribution of the misalignment angle, this model can reproduce the Planck-observed (and parity-violating) TB correlation. The skewing of the misalignment angle necessary to explain TB will cause a yet-unobserved, positive EB dust correlation, a possible target for future experiments.

CFD Simulation of the Dispersion of Binary Dust Mixtures in the 20 L Vessel

There are at least two main requirements for repeatable and reliable measurements of flammability and explosibility parameters of dusts: a uniform dispersion of solid particles inside the test vessel, and a homogeneous degree of turbulence. In several literature works, it has been shown that, in the standard 20 L sphere, the dust injection system generates a non-uniform dust cloud, while high gradients characterize the turbulent flow field. In this work, the dust dispersion inside the 20 L sphere was simulated for nicotinic acid/anthraquinone mixtures (with different pure dust ratios, while keeping the total dust concentration constant) with a validated three-dimensional CFD model. Numerical results show that the fields of dust concentration, flow velocity and turbulence are strongly affected by both diameter and density of the pure dusts. These different dust properties lead to segregation phenomena with the formation of zones richer in one component and leaner in the other one and vice versa, and also result in preferential paths for the solid particles inside the sphere. Overall, the obtained results highlight the need for developing a dust injection system able to overcome the shortcomings of the actual one even when testing dust mixtures.

The Guarantee Strategy for Reliable Operation of the Precipitation withMobile Electrode Electrostatic Technology

Research in view of the conventional electrostatic precipitator for ultra fine dust, dust ratio resistance and high viscosity difficult removal, secondary problems such as dust, and domestic environmental protection professional factory introduction, digestion and innovation, a new type of electrostatic precipitator, based on the technology of moving electrode has the following characteristics: low operating cost, the filter processing efficiency, equipment, the advantages of the small resistance, but the moving parts, in order to promote its reliability, the research for mobile motor technology principle and innovative design, this paper discusses the moving electrode duster guarantee reliable operation strategy, in order to offer reference to related staff.

Source apportionment of potentially toxic elements in street dust of a coal mining area in Chhattisgarh, India, using multivariate and lead isotopic ratio analysis.

Street dust of Korba, Chhattisgarh, an urban industrial hub in one of India's major coal mining areas, has been analysed for profiling and sourcing of Pb and other potentially toxic elements (PTEs). Lead isotopic ratio of dust, coal, diesel, fly ash and human blood of Korba is being reported for the first time in this study. The mean concentrations (in mg/kg) of Al, V, Cr, Fe, Mn, Ni, Cu, Zn, Cd and Pb were higher than World Background soil and Reference soil USA values and decreased in the order of Al (17000) > Fe (7550) > Mn (2740) > Cr (833) > Ni (571) > Zn (231) > Cu (152) > V (145) > Pb (98.6) > U (7.9) > Cd (1.34). About 25% of the sampled dust had Pb Igeo belonging to class IV category of heavy contamination. Dust from industrial areas was highly enriched with Cr, Cu, Pb and Mn, while those from coal mining areas had high mean V concentration. Principal component analysis extracted Al, Fe, Mn, Zn, Pb and U with the highest loading factors in Component 1 indicative of their lithogenic and anthropogenic sources. The lead isotopic ratios of the dust, coal, diesel, fly ash and eight human blood samples clustered linearly in the 207Pb/204Pb vs 208Pb/204Pb and 206Pb/204Pb vs 208Pb/204Pb plots. Airborne lead deposition from diesel-based traffic exhausts and fly ash contributed to the human blood lead level besides coal mining activities. Geospatially, while Pb was mainly concentrated in the residential, industrial and coal-mining areas, Zn and Mn were mainly distributed in the roadside areas of industrial centres.