Reduction Of Dust Emissions Research Articles

Utilization of deep learning tools to map and monitor biological soil crusts

Biological soil crusts (biocrusts) form a layer of only one to few centimeters depth on the soil surface and occur mostly in hot and cold deserts. Biocrusts have a major impact on different processes in these ecosystems, like carbon and nitrogen cycling, biodiversity preservation, erosion protection and soil dust emission reduction, but also react highly sensitive upon climate alterations and land use intensification. Therefore, monitoring tools are required to keep track of the changes of these specialized communities in an altering environment. In the current study, we applied a semantic image segmentation approach, using neural networks. One main problem to be solved was, that the training data and target data, on which the model is applied, are often recorded with different camera devices. This leads to different statistical properties of the image data, like different scale, resolution, brightness etc., which could significantly affect the model's performance. To solve this problem, we propose a new domain adaption method using a joint energy-based approach. To test a semantic segmentation approach in general, we utilized biocrust imagery taken in Utah (United States of America) and two sub datasets from the National Park Gesäuse (Austria). Here, we achieved highly reliable results with an overall classification accuracy of 85.9% for the USA data and 88.6% and 91.4%, respectively, for the two sub datasets of the National Park Gesäuse. To test our joint energy-based domain adaption approach, we used the two sub datasets from the National Park Gesäuse, which were recorded with different camera devices. With this newly established approach, we improved the accuracy of our segmentation on the unlabeled sub dataset from 70.4% to 75.3%. The results suggest that joint energy-based modelling is a well-suited domain adaption method for semantic segmentation that could be applied to face various deep learning and image-based biomonitoring challenges.

Long-term characteristics of dust aerosols over central China from 2010 to 2020 observed with polarization lidar

Plenty of dust aerosols are emitted into the atmosphere in East Asian regions and significantly impact the regional environment and climate. In the past decade, the frequency of dust storm outbreaks has largely declined in the sources of Asian dust. However, it is still rarely reported how the dust properties after long-range transport in the downstream regions respond to this downtrend. Here we report on the long-term characteristics of dust aerosols over central China with the observations of a polarization lidar at Wuhan (30.5°N, 114.4°E) during 2010–2020. The dust optical depths (DOD) exhibit a decrease trend with a rate of −0.011 yr−1, accounting for 22% of the decrease rate for total aerosol optical depths (AOD) in Wuhan. The mass concentration and columnar mass density of dust also decline with a rate of −2.03 μg·m−3·yr−1 and -1.97 mg·m−2·yr−1, respectively. Spring and winter are the most active seasons for dust intrusion, with seasonal mean DOD of 0.21 and 0.15, respectively. Compared with spring, dust aerosols in winter generally concentrate at lower levels below 1.0 km with a slightly smaller particle depolarization ratio of 0.11 (0.14 in spring), attributing to the weakened nonspherical shape of dust particles under wintertime high-level moisture/polluted conditions. Both the surface PM10 concentration and lidar-derived dust mass concentration at 0.3 km present a downtrend with a rate of −8.0 μg·m−3·yr−1 and -20.1 μg·m−3·yr−1, respectively. This study provides a comprehensive long-term and seasonal analysis of dust properties in central China, which can supplement our understanding of the feedback in the downstream regions to the reduction of dust emissions in the deserts of East Asia.

PROTECTION OF THE ATMOSPHERE OF URBANIZED AREAS FROM DUST EMISSIONS DURING THE MANUFACTURE OF AERATED CONCRETE STRUCTURES

The article provides a solution to the urgent task of ensuring the protection of the natural environment and vital human interests from the negative effects of dust emissions generated during the production of aerated concrete and construction products based on it. It has been established that when traditional dust emission cleaning systems with cyclones is used, dust is emitted into the atmospheric air, and up to 100 % of the mass of dust is represented with particles of up to 20 microns in size. At the same time their median diameter is 12 microns, the percentage of particles with sizes less than 10 microns (PM10) is 40 %, the percentage of particles with sizes less than 2,5 microns (PM2,5) is 0.5 %. The percentage of particles in the atmospheric air near the industrial site in the summer varies: for PM10 – from 12 % to 40 %; for PM2,5 – from 0.3 % to 0.5 %. At the border of the sanitary protection zone these values are 80 % and 0.5 %, respectively. In order to reduce dust entering the atmosphere during the production of aerated concrete and construction products based on it, two options for the layout of emission dust removal systems with two consecutively installed dust collectors with counter-rotating flows, two additional devices of smaller sizes, with the organization of suction from the hopper of the main dust collector of the second stage are proposed and from the bunker of one of the additional devices. The use of the proposed dust cleaning system showed that the content of PM10 particles in the stream, emitted into the atmosphere, was decreased by 40 %, the content of PM2,5 particles – by 20 %. At the same time, the emission of dust into the atmosphere was decreased by 8.9 times. Dependencies characterizing the degree of reduction of dust emissions into the atmosphere were established, as well as the ranges of changes in the regime and design parameters of the proposed dust cleaning systems, which ensure the least amount of dust entering the environment and the least energy costs for carrying out dust removal processes during the production of aerated concrete and building structures based on it.

Impact of dust aerosols on the Indian Summer Monsoon Rainfall on intra-seasonal time-scale

The Indian subcontinent is a major hotspot of aerosol loading and several studies have demonstrated the importance of interaction between Asian dust aerosols and the Indian Summer Monsoon Rainfall (ISMR). However, a few studies have suggested a declining trend in the pre-monsoon dust loading over the Indian region. The present study investigates how the decrease in dust emissions influences the intensity of the monsoon rainfall over the Indian region using a fully coupled Weather Research and Forecasting model coupled with chemistry (WRF-Chem). We have conducted two sets of simulation experiments for the June-July-August-September (JJAS) season of 2017: (1) a control experiment with the default dust aerosol emissions, and (2) a sensitivity experiment by reducing dust emissions by 60%. Our analyses show that the reduction in dust emissions significantly alters the spatial distribution of seasonal mean monsoon rainfall with enhanced rainfall over the Bay of Bengal (BoB) and eastern coastal regions, and decreased rainfall over the lower Indo-Gangetic Plain (IGP), and parts of Central India (CI). It is found that the low aerosol loading conditions alter the large-scale circulation patterns along the tropical/sub-tropical region centred between 15°N and 35°N and 40°E −130°E, and through dynamical feedback, strengthens the convective rainfall over the BoB region. As a result, the 10–20 days sub-seasonal mode of the ISMR strengthens, facilitating enhanced westward propagation of rain-bearing systems formed over northern BoB which provides substantial rainfall over vast regions of the Indian subcontinent.

Drivers of recent decline in dust activity over East Asia

It is essential to understand the factors driving the recent decline of dust activity in East Asia for future dust projections. Using a physically-based dust emission model, here we show that the weakening of surface wind and the increasing of vegetation cover and soil moisture have all contributed to the decline in dust activity during 2001 to 2017. The relative contributions of these three factors to the dust emission reduction during 2010–2017 relative to 2001 are 46%, 30%, and 24%, respectively. Much (78%) of the dust emission reduction is from barren lands, and a small fraction (4.6%) of the reduction is attributed to grassland vegetation increase that is partly ascribed to the ecological restoration. This suggests that the ecological restoration plays a minor role in the decline of dust activity. Rather, the decline is mainly driven by climatic factors, with the weakening of surface wind playing the dominant role.

Dust emission reduction enhanced gas-to-particle conversion of ammonia in the North China Plain

Ammonium salt is an important component of particulate matter with aerodynamic diameter less than 2.5 µm (PM2.5) and has significant impacts on air quality, climate, and natural ecosystems. However, a fundamental understanding of the conversion kinetics from ammonia to ammonium in unique environments of high aerosol loading is lacking. Here, we report the uptake coefficient of ammonia (γNH3) on ambient PM2.5 varying from 2.2 × 10−4 to 6.0 × 10−4 in the North China Plain. It is significantly lower than those on the model particles under simple conditions reported in the literature. The probability-weighted γNH3 increases obviously, which is well explained by the annual decrease in aerosol pH due to the significant decline in alkali and alkali earth metal contents from the emission source of dust. Our results elaborate on the complex interactions between primary emissions and the secondary formation of aerosols and the important role of dust in atmospheric chemistry.

Study on Fugitive Dust Control Technologies of Agricultural Harvesting Machinery

The fugitive dust generated by agricultural harvesting machinery not only causes harm to production safety, but also affects the living environment of people in agricultural areas. This is also one of the hot issues that have emerged in the green development of rural areas in recent years, which is related to agricultural safety and hygiene culture. Due to the lack of relevant research, many researchers still have considerable controversy on the issue of agricultural dust. Therefore, in combination with the actual production of agricultural mechanization, according to the cause of dust generation and particle characteristics, the selection of appropriate dust reduction technology and detection methods is of great significance for the research on the control of dust from agricultural harvesting machinery. Aiming at the dust problem in agricultural mechanization production, this research first introduces the relationship between fugitive dust and atmospheric particulate matter and the main components of fugitive dust, and then focuses on the causes of dust generated by wheat harvesters and peanut harvesters in field operations, and explains the main hazards of dust to human health, ecological environment, and climate. This study introduces four fugitive dust emission reduction technologies and five particle measurement methods, and compares and analyzes their feasibility in the application of agricultural harvesting machinery dust control. Finally, we put forward conclusions and suggestions on the dust control technology of agricultural harvesting machinery in order to provide reference for the control of agricultural harvesting machinery dust, improve the field operation environment, and promote the green development of modern agriculture.

ANALYSIS OF TECHNICAL AND TECHNOLOGICAL EQUIPMENT PROCESSES OF EXPANDED FEED PREPARATION

Extruders and expanders belong to the family of HTST (high temperature short-term) equipment capable of performing the task of cooking food and feed under high pressure. Because the effects of high temperatures occur only for a short time, the undesirable effects of denaturation of proteins, amino acids, vitamins, starch and enzymes are limited. Physical and technological aspects such as heat transfer, mass transfer, pulse transfer, temperature time have a strong influence on the properties of food and feed during extrusion and expanded cooking and can significantly affect the quality of the final product. The aim of the research is to analyze the technical and technological equipment of extrusion and expanded feed preparation processes and substantiate the feasibility of using expanders. The use of expanders in the feed pellet processing line has many advantages, the most important of which are: improved feed nutrition (better feed conversion); more efficient use of low-quality raw materials or even waste; sterilization of bacteriologically contaminated materials; better control of liquid additives; reduction of energy consumption of pellet press; increasing the productivity of the pellet press; expanding the product range; the possibility of using fibrous materials; reduction of dust emissions and losses during granulation. The economic and food aspects of the use of expanders make their use understandable and justified in the feed industry. The use of an expander-granulator kit increases the cost of production by 10-15 % compared to granulation alone. However, the overall income and expenditure account is positive due to the qualitative results that offset the costs incurred. The use of expanders in the global feed industry is growing every year, which is also reflected in the wider range of recently produced animal feed. The benefits of this technique are beginning to be appreciated in underdeveloped countries. Its usefulness is fully confirmed by feed manufacturers who have already implemented the above production methods.

Improvements of ADAM3 by Incorporating New Dust Emission Reduction Formulations Based on Real-Time MODIS NDVI

Dust events in Northeast Asia have several adverse effects on human health, agricultural land, infrastructure, and transport. Wind speed is the most important factor in determining the total dust emission at the land surface; however, various land-surface conditions must be considered as well. Recently, the Korea Meteorological Administration updated the dust emission reduction factor (RF) in the Asian Dust Aerosol Model 3 (ADAM3) using data from the normalized difference vegetation index (NDVI) of the Moderate Resolution Imaging Spectroradiometer (MODIS). We evaluated the improvements of ADAM3 according to soil types. We incorporated new RF formulations in the evaluation based on real-time MODIS NDVI data obtained over the Asian dust source regions in northern China during spring 2017. This incorporation improved the simulation performance of ADAM3 for the PM10 mass concentration in Inner Mongolia and Manchuria for all soil types, except Gobi. The ADAM3 skill scores for sand, loess, and mixed types in a 24 h forecast increased by 6.6%, 20.4%, and 13.3%, respectively, compared with those in forecasts employing the monthly RF based on the NDVI data. As surface conditions in the dust source regions continually change, incorporating real-time vegetation data is critical to improving performance of dust forecast models such as ADAM3.

Operational tests of an electrostatic precipitator reducing low dust Indexed by: emission from solid fuels combustion

The article presents the continuation of the research aimed at designing, manufacturing and selecting the operating parameters of the electrostatic precipitator for household applications. The tests were carried out in the laboratory and real conditions. The object of the research was a pre-production prototype of the electrostatic precipitator installed in the flue gas duct of a single-family building. The source of exhaust gases was a coal-fired, low-temperature water heating boiler with a nominal power of 21 kW (old generation boiler-year of production: 2007). The obtained results showed that the adopted design of the electrostatic precipitator enables the reduction of dust emissions generated in the combustion of solid fuels in households at relatively low operating costs.

Dust emission reduction in iron ore concentrate production plant using value engineering method.

Dust emission is one of the critical problems of the mining industry. Dust emission can cause respiratory diseases among workers and adjacent residents of the factory and environmental pollution in the region. This study aims to reduce dust emissions of an iron ore concentrate plant in Iran. Applying dust control methods can affect the production process. Therefore, in this study, the value engineering (VE) method has been used, which focuses on improving the processes without affecting the main functions. This method is implemented in three stages. In the pre-study stage of VE, the prerequisites of study, such as determining the management requirements, study scope, evaluation criteria, forming the VE team, and planning, were met. In the study stage, the required information was collected; the studied process functions were identified and ranked; 62 ideas were created based on the functions and then evaluated; the final scenarios for the selected device, hopper, were developed and ranked using the VIKOR method; and finally, confirmation of the results by the management was obtained. In the post-study stage, the results will be implemented. The approach of this study was based on maintaining the functions of the production process and production rate and finding the most effective solution to reduce dust and environmental hazards, the most efficient solution in terms of performance, and the most cost-effective solution in terms of fixed and variable costs. According to the results, dry and wet dust suppression systems are the best options among the scenarios to meet the objectives of this study.

Experimental evaluation of primary measures for NOX and dust emission reduction in a novel 200 kW multi-fuel biomass boiler

The aim of this work is to utilize various biogenic fuels without ash slagging and to significantly reduce NOX and particulate matter emissions in comparison to modern combustion technologies. For this purpose, a novel small-scale multi-fuel biomass grate furnace technology was developed and experimentally investigated. It employs a low oxygen concentration in the fixed-bed and a double air staging, including the supply of flue gas recirculation. In this way slagging is prevented on the grate, reducing the release of ash-forming volatiles, NOX emissions are minimized in the reduction zone and an efficient flue gas burnout is achieved in the tertiary zone. Wood pellets and chips as well as miscanthus briquettes were investigated.The measured total particle emissions showed a reduction of 68% for pellets and 70% for wood chips compared to typical small-scale furnaces. Furthermore, a reduction of NOX emissions of 39% for wood chips, 40% for wood pellets and 45% for miscanthus briquettes was achieved compared to typical small-scale furnaces. The experimental parameter study provided fundamental insights into the various mechanisms involved in this novel technology, which is close to market introduction, and proved its high fuel flexibility and great potential for particulate matter and NOX emission reduction.

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

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.

Reduction of dust emission by Coromax micro-pulse power supplies at an oil shale fired power plant

Several classes of power supplies for ESP exist and the choice of the correct class is related to the resistivity of the dust to filter. The case of a power plant with high-resistivity dust emissions, for which the replacement of the existing power supplies with micro-pulse power supplies has succeeded in halving the dust emission level, is presented. The presentation is completed with data measured before and after the installation of the new power supplies and with a simplified analytical explanation supporting the results.

New tool for reduction of harmful particulate dispersion and to improve machining quality when trimming carbon/epoxy composites

Conventional machining of carbon fiber reinforced plastic composites (CFRPs) generates minute chips that get suspended in air causing a hazard compromising operator safety. This study investigates the influence of cutting parameters (feed speed, cutting speed, radial depth of cut, tool geometry and tool wear) during trimming of CFRP on the form and quantity of harmful particles dispersed. Also, performance of two classical PCD tool geometries (two straight flutes, two helix flutes) have been compared with newly designed (in collaboration with ASAHI Company) four serrated straight flutes for the purpose of dust emission reduction. The quantification of the number of harmful particles was estimated using laser spectroscopic dust monitor. The results reveal that, trimming with a combination of higher feed speed and lower cutting speed can reduce the dispersion of harmful particles. Further, the four serrated straight flutes recorded the least number of harmful particles compared to the conventional tools.

Improved Dust Emission Reduction Factor in the ADAM2 Model Using Real-Time MODIS NDVI

The Korea Meteorological Administration has employed the Asian Dust Aerosol Model 2 (ADAM2) to forecast Asian dust events since 2010, where the dust emission flux is proportional to the fourth power of the friction velocity. Currently, the dust emission reduction factor (RF) is determined by the normalized difference vegetation index (NDVI). This study aims to improve the forecasting capability of ADAM2 by developing a daily dust RF using both monthly (January 2007 to December 2016) and real-time moderate resolution imaging spectroradiometer (MODIS) NDVI data. We also developed a look-up table to transform the RF using NDVI and a system to update the RF by producing MODIS NDVI data for the last 30 days. Using these data, new RFs can be produced every day. To examine the impact of RF modification, the current (CTL) and new (EXP) RFs are compared during the period from March to May 2017. The simulations are verified by ground-based PM10 observations from China and Korea. Accordingly, root mean square errors (RMSEs) are reduced by 11.58% when RF is updated using real-time NDVI data. The results suggest that recent daily NDVI data contribute positively to the forecasting ability of ADAM2, in the dust source and downwind regions.

Preliminary assessment of the wind conditions as a potential for using wind micro-installation to improve air quality in Poland

Poland has been struggling with the problem of exceedance of the permissible levels of air pollutions such as particulate matter (PM10, PM2.5) and benzo(a)pyrene (BaP) for several years. In the years 2007-2015 the concentrations of PM10 and BaP exceeded the European Union (EU) limit values. The vast majority of the country is characterised by wind energy zones described as very favorable and favorable. Facing the current legal regulations, wind micro-installations are becoming an opportunity to use the potential of wind energy in Poland. The micro-installations market in Poland is constantly growing. In 2017 there was recorded a nearly ten-fold increase in the number of micro-installations of renewable energy sources connected to the network in regard of 2015. The analysis based on available wind energy resources and available technologies of small wind turbines on the market showed that by installing a 10 kW turbine in the zone with the most favorable wind conditions (1000 kWh/m2/year) one can avoid 93kg of dust emissions to the air and 140 kg of CO and 6222 kg of CO2. The calculated reduction of dust emissions for 3 kW wind turbine in area of Rabka-Zdrój is about 0.8 kg, in the case of BaP 0.0003 kg, and for CO2 47.3 kg.

고등어 조리 시 발생하는 미세먼지의 입경 분석

In this study, the characteristics of the dust emission according to the presence or absence of operation of the gas stove were analyzed by particle size analysis and density estimation while the mackerel was cooked while the fan was placed on the gas stove used in the home. The experiment was carried out using 20 mackerel of normal size at home. Commercially available canola oil was used as edible oil. In order to understand the characteristics such as particle size distribution of fine dust, light scattering measurement method which can be measured at intervals of several seconds was used. Particles generated by combustion of gas stove, particles formed by heating cooking oil, and particles generated by heating mackerel fish meat are judged to be nano size particles smaller than 1 ㎛. Therefore, it is necessary to use precise measurement method rather than the measurement method using the filter which is currently being measured in the measurement of the particles discharged from the fuel combustion or food cooking in the future. Analyzing the particle size and density of the dust emitted from the cooking stove is expected to contribute technically to the reduction of dust emissions from the cooking process of gas and fuel facilities at home and commercial facilities.

Reduction of Dust Emission by Monodisperse System Technology for Ammonium Nitrate Manufacturing

Prilling is a common process in the fertilizer industry, where the fertilizer melt is converted to droplets that fall, cool down and solidify in a countercurrent flow of air in a prilling tower. A vibratory granulator was used to investigate liquid jet breakup into droplets. The breakup of liquid jets subjected to a forced perturbation was investigated in the Rayleigh regime, where a mechanical vibration was applied in order to achieve the production of monodispersed particles. Images of the jet trajectory, breakup, and the formed drops were captured using a high-speed camera. A mathematical model for the liquid outflow conditions based on a transient two-dimensional Navier–Stokes equation was developed and solved analytically, and the correlations between the process parameters of the vibrator and the jet pressure that characterize their disintegration mode were identified. The theoretical predications obtained from the correlations showed a good agreement with the experimental results. Results of the experiments were used to specify the values of the process parameters of the vibration system, and to test them in the production environment in a mode of monodispersed jet disintegration. The vibration frequency was found to have a profound effect on the production of monodispersed particles. The results of experiments in a commercially-sized plant showed that the granulator design based on this study provided prills with a narrower size range compared to the conventional granulators, which resulted in a substantial reduction in dust emission.

Effects of climate changes on dust aerosol over East Asia from RegCM3

In order to understand impacts of global warming on dust aerosol over East Asia, a regional climate model (RegCM3) coupled with a dust model is employed to simulate the present (1991–2000, following the observed concentration of the greenhouse gases) and future (2091–2100, following the A1B scenario) dust aerosol. Three experiments are performed over East Asia at a horizontal resolution of 50 km, driven by the outputs from a global model of the Model for Interdisciplinary Research on Climate (MIROC3.2_hires), two without (Exp.1 for the present and Exp.2 for the future) and one with (Exp.3 for the future) the radiative effects of dust aerosols. Effects of climate changes on dust aerosols and the feedback of radiative effects in the future are investigated by comparing differences of Exp.2 and Exp.1, Exp.3 and Exp.2, respectively. Results show that global warming will lead to the increases of dust emissions and column burden by 2% and 14% over East Asia, characterized by the increase in December–January–February–March (DJFM) and the decrease in April–May (AM). Similar variations are also seen in the projected frequencies of high dust emission events, showing an advanced active season of dust in the future. The net top-of-atmosphere (TOA) radiative forcing is positive over the desert source regions and negative over downwind regions, while the surface radiative forcing is negative over the domain, which will lead to a reduction of dust emissions and column burden.