scholarly journals Study of component composition and particle size distribution of dust emissions to solve the problems of environmental quality management

2014 ◽  
Author(s):  
S. Yu. Zagorodnov ◽  
A. A. Kokoulina ◽  
E. V. Popova
Keyword(s):  
Particle Size ◽  
Quality Management ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Environmental Quality ◽  
Component Composition ◽  
Dust Emissions

scholarly journals Evaluation of natural aerosols in CRESCENDO Earth system models (ESMs): mineral dust

2021 ◽  
Vol 21 (13) ◽  
pp. 10295-10335
Author(s):  
Ramiro Checa-Garcia ◽  
Yves Balkanski ◽  
Samuel Albani ◽  
Tommi Bergman ◽  
Ken Carslaw ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Dust Particle ◽  
Wet Deposition ◽  
Earth System ◽  
Dust Emissions ◽  
Dust Sources ◽  
Global Emissions ◽  
Earth System Models

Abstract. This paper presents an analysis of the mineral dust aerosol modelled by five Earth system models (ESMs) within the project entitled Coordinated Research in Earth Systems and Climate: Experiments, kNowledge, Dissemination and Outreach (CRESCENDO). We quantify the global dust cycle described by each model in terms of global emissions, together with dry and wet deposition, reporting large differences in the ratio of dry over wet deposition across the models not directly correlated with the range of particle sizes emitted. The multi-model mean dust emissions with five ESMs is 2836 Tg yr−1 but with a large uncertainty due mainly to the difference in the maximum dust particle size emitted. The multi-model mean of the subset of four ESMs without particle diameters larger than 10 µ m is 1664 (σ=651) Tg yr−1. Total dust emissions in the simulations with identical nudged winds from reanalysis give us better consistency between models; i.e. the multi-model mean global emissions with three ESMs are 1613 (σ=278) Tg yr−1, but 1834 (σ=666) Tg yr−1 without nudged winds and the same models. Significant discrepancies in the globally averaged dust mass extinction efficiency explain why even models with relatively similar global dust load budgets can display strong differences in dust optical depth. The comparison against observations has been done in terms of dust optical depths based on MODIS (Moderate Resolution Imaging Spectroradiometer) satellite products, showing global consistency in terms of preferential dust sources and transport across the Atlantic. The global localisation of source regions is consistent with MODIS, but we found regional and seasonal differences between models and observations when we quantified the cross-correlation of time series over dust-emitting regions. To faithfully compare local emissions between models we introduce a re-gridded normalisation method that can also be compared with satellite products derived from dust event frequencies. Dust total deposition is compared with an instrumental network to assess global and regional differences. We find that models agree with observations within a factor of 10 for data stations distant from dust sources, but the approximations of dust particle size distribution at emission contributed to a misrepresentation of the actual range of deposition values when instruments are close to dust-emitting regions. The observed dust surface concentrations also are reproduced to within a factor of 10. The comparison of total aerosol optical depth with AERONET (AErosol RObotic NETwork) stations where dust is dominant shows large differences between models, although with an increase in the inter-model consistency when the simulations are conducted with nudged winds. The increase in the model ensemble consistency also means better agreement with observations, which we have ascertained for dust total deposition, surface concentrations and optical depths (against both AERONET and MODIS retrievals). We introduce a method to ascertain the contributions per mode consistent with the multi-modal direct radiative effects, which we apply to study the direct radiative effects of a multi-modal representation of the dust particle size distribution that includes the largest particles.

scholarly journals Parameterization of dust emissions in the global atmospheric chemistry-climate model EMAC: impact of nudging and soil properties

2012 ◽  
Vol 12 (22) ◽  
pp. 11057-11083 ◽  
Author(s):  
M. Astitha ◽  
J. Lelieveld ◽  
M. Abdel Kader ◽  
A. Pozzer ◽  
A. de Meij
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Atlantic Ocean ◽  
Size Distribution ◽  
Atmospheric Chemistry ◽  
Soil Particle ◽  
Dust Emissions ◽  
Desert Dust ◽  
Soil Particle Size ◽  
Soil Particle Size Distribution

Abstract. Airborne desert dust influences radiative transfer, atmospheric chemistry and dynamics, as well as nutrient transport and deposition. It directly and indirectly affects climate on regional and global scales. Two versions of a parameterization scheme to compute desert dust emissions are incorporated into the atmospheric chemistry general circulation model EMAC (ECHAM5/MESSy2.41 Atmospheric Chemistry). One uses a globally uniform soil particle size distribution, whereas the other explicitly accounts for different soil textures worldwide. We have tested these two versions and investigated the sensitivity to input parameters, using remote sensing data from the Aerosol Robotic Network (AERONET) and dust concentrations and deposition measurements from the AeroCom dust benchmark database (and others). The two versions are shown to produce similar atmospheric dust loads in the N-African region, while they deviate in the Asian, Middle Eastern and S-American regions. The dust outflow from Africa over the Atlantic Ocean is accurately simulated by both schemes, in magnitude, location and seasonality. Approximately 70% of the modelled annual deposition data and 70–75% of the modelled monthly aerosol optical depth (AOD) in the Atlantic Ocean stations lay in the range 0.5 to 2 times the observations for all simulations. The two versions have similar performance, even though the total annual source differs by ~50%, which underscores the importance of transport and deposition processes (being the same for both versions). Even though the explicit soil particle size distribution is considered more realistic, the simpler scheme appears to perform better in several locations. This paper discusses the differences between the two versions of the dust emission scheme, focusing on their limitations and strengths in describing the global dust cycle and suggests possible future improvements.

scholarly journals Evaluation of natural aerosols in CRESCENDO-ESMs: Mineral Dust

2020 ◽  
Author(s):  
Ramiro Checa-Garcia ◽  
Yves Balkanski ◽  
Samuel Albani ◽  
Tommi Bergman ◽  
Ken Carslaw ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Dust Particle ◽  
Mineral Dust ◽  
Radiative Effects ◽  
Dust Emissions ◽  
Dust Sources ◽  
Global Consistency ◽  
The Difference

Abstract. This paper presents an analysis of the mineral dust aerosol modelled by five Earth System Models (ESM) within the Coordinated Research in Earth Systems and Climate: Experiments, kNowledge, Dissemination and Outreach (CRESCENDO) project. We quantify the global dust cycle described by each model in terms of global emissions together with dry and wet depositions, reporting large differences in ratio of dry over wet deposition across the models not directly correlated with the range of particle sizes emitted. The multi-model mean dust emissions was 2954 Tg yr−1 but with a large uncertainty due mainly to the difference in maximum dust particle size emitted. For the subset of ESMs without particles larger than 10 μm we obtained 1664 (σ = 650) Tg yr−1. Total dust emissions with identical nudged winds from reanalysis give us better consistency between models with 1530 (σ = 282) Tg yr−1. Significant discrepancies in the globally averaged dust mass extinction efficiency explain why even models with relatively similar dust load global budgets can display strong differences in dust optical depths. The comparison against observations has been done in terms of dust optical depths based on MODIS satellite products, showing a global consistency in terms of preferential dust sources and transport across the Atlantic. However, we found regional and seasonal differences between models and observations when we quantified the cross-correlation of time-series over dust emitting regions. To faithfully compare local emissions between models we introduce a re-gridded normalization method, that also can be compared with satellite products derived from dust events frequencies. Dust total depositions are compared with instrumental network to assess global and regional differences. We found that models agree with observations distant from dust sources within a factor 10, but the approximations of dust particle size distribution at emission contributed to a misrepresentation of the actual range of deposition values when instruments are close to dust emitting regions. The observational dust surface concentrations also are reproduced within a factor 10. The comparison of total aerosol optical depths with AERONETv3 stations where dust is dominant shows large differences between models, however with an increase of the inter-model consistency when the simulations are conducted with nudged-winds. The increase of the model ensemble consistency also means a better agreement with observations, which we have ascertained for dust total deposition, surface concentrations and optical depths (against both AERONETv3 and MODIS-DOD retrievals). We estimated the direct radiative effects of a multi-modal representation of the dust particle size distribution that includes the largest particles measured at FENNEC experiment. We introduced a method to ascertain the contributions per mode consistent with the multimodal direct radiative effects.

scholarly journals Rational crushing of mineral raw materials by well charges as a factor of environmental safety of blasting works in quarries

2021 ◽  
Vol 64 ◽  
pp. 138-153
Author(s):  
V Kolesnik ◽  
A Pavlychenko ◽  
T Kholodenko ◽  
A Kirichenko
Keyword(s):  
Particle Size ◽  
Rock Mass ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Construction Materials ◽  
Environmental Safety ◽  
Shock Adiabats ◽  
Rock Destruction ◽  
Dust Emissions

Purpose. Improving the environmental safety of blasting operations in quarries for the extraction of non-metallic and construction materials based on their rational explosive crushing, aimed at reducing the effect of overgrinding, accompanied by the formation of fine fractions of materials and significant dust emissions. The research methodology provided a theoretical analysis of the destruction processes of a rock massif by well charges of explosives on the basis of calculations of shock adiabats of an explosive wave in rocks at different speeds of detonation of explosives. Experimental verification of the identified patterns was performed by assessing the quality of blasting by the particle size distribution of the rock in the collapse. Research results. The scientific and practical task of ensuring rational explosive crushing of materials in quarries with the use of elongated borehole charges has been solved. Mechanisms for the destruction of rock massifs and the peculiarities of the distribution of destruction zones by dispersed composition have been established, which contributes to the reduction of dust emissions into the atmosphere to an acceptable level of environmental safety of blasting operations in quarries. Comparative estimates of the shock load during the explosion of the explosive charge for the main rocks at different levels of the rate of detonation of charges are given. The dependence of the volume of overgrinding rock in the zone of its adjacency to the charge on the detonation velocity of explosives has been established. An experimental verification of the identified patterns in the current quarry by assessing the quality of blasting by the particle size distribution of rock mass in its collapse after experimental explosions with different parameters is done. Scientific novelty. The multiphase process of rock destruction by explosion was investigated by the calculated determination of the parameters of the shock adiabats of the blast wave in different rocks and at different detonation velocities of explosives. It is shown that during the destruction of a rock mass by the explosion of an elongated borehole charge of explosives, several specific zones of destruction are formed, the characteristics of which differ in particle size distribution. The area of controlled crushing is highlighted, where the intensity of rock destruction can be changed by adjusting the parameters of the explosive load and the area of little or almost unregulated crushing. The possibility of managing the process of dust formation and, accordingly, the level of environmental safety of blasting works in quarries for the extraction of non-metallic and construction materials is substantiated. Practical meaning. The identified patterns and provisions to reduce the effect of mineral overgrinding were used in the development of measures to improve the environmental safety of blasting in the quarry, which, in particular, provided an increase in well spacing in the range up to 3.0-3.4 m and reduce specific energy consumption from 1.27 g/cm3 to 0.97 g/cm3.

Effects of Particle Size Distribution on Corrosion Rate of Carbon Steel in Soil

2020 ◽  
Vol 69 (4) ◽  
pp. 102-106
Author(s):  
Shota Ohki ◽  
Shingo Mineta ◽  
Mamoru Mizunuma ◽  
Soichi Oka ◽  
Masayuki Tsuda
Keyword(s):  
Particle Size ◽  
Carbon Steel ◽  
Corrosion Rate ◽  
Particle Size Distribution ◽  
Size Distribution

DENSE SPRAY CORRECTIONS FOR DIFFRACTION-BASED PARTICLE SIZE DISTRIBUTION MEASUREMENTS

1995 ◽  
Vol 5 (1) ◽  
pp. 75-87 ◽  
Author(s):  
Christine M. Woodall ◽  
James E. Peters ◽  
Richard O. Buckius
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution
Sign in / Sign up

Export Citation Format

Share Document