Assessing the Impact of Fugitive Dust Emissions from Cement Silos at Cluster of Concrete Batching Facilities Using Air Dispersion Modeling

This research assessed the environmental impact of cement silos emission on the existing concrete batching facilities in M35-Mussafah, Abu Dhabi, United Arab Emirates. These assessments were conducted using an air quality dispersion model (AERMOD) to predict the ambient concentration of Portland Cement particulate matter less than 10 microns (PM10) emitted to the atmosphere during loading and unloading activities from 176 silos located in 25 concrete batching facilities. AERMOD was applied to simulate and describe the dispersion of PM10 released from the cement silos into the air. Simulations were carried out for PM10 emissions on controlled and uncontrolled cement silos scenarios. Results showed an incremental negative impact on air quality and public health from uncontrolled silos emissions and estimated that the uncontrolled PM10 emission sources contribute to air pollution by 528958.32 kg/Year. The modeling comparison between the controlled and uncontrolled silos shows that the highest annual average concentration from controlled cement silos is 0.065 μg/m3, and the highest daily emission value is 0.6 μg/m3;both values are negligible and will not lead to significant air quality impact in the entire study domain. However, the uncontrolled cement silos’ highest annual average concentration value is 328.08 μg/m3. The highest daily emission average value was 1250.09 μg/m3;this might cause a significant air pollution quality impact and health effects on the public and workers. The short-term and long-term average PM10 pollutant concentrations at these receptors predicted by the air dispersion model are discussed for both scenarios and compared with local and international air quality standards and guidelines.

Analysis on emission factor of fugitive dust from road traffic

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Comparative Analysis of PM10 Emission Rates from Controlled and Uncontrolled Cement Silos in Concrete Batching Facilities

This research study quantifies the PM10 emission rates (g/s) from cement silos in 25 concrete batching facilities for both controlled and uncontrolled scenarios by applying the USEPA AP-42 guidelines step-by-step approach. The study focuses on evaluating the potential environmental impact of cement dust fugitive emissions from 176 cement silos located in 25 concrete batching facilities in the M35 Mussafah industrial area of Abu Dhabi, UAE. Emission factors are crucial for quantifying the PM10 emission rates (g/s) that support developing source-specific emission estimates for areawide inventories to identify major sources of pollution that provide screening sources for compliance monitoring and air dispersion modeling. This requires data to be collected involves information on production, raw material usage, energy consumption, and process-related details, this was obtained using various methods, including field visits, surveys, and interviews with facility representatives to calculate emission rates accurately. Statistical analysis was conducted on cement consumption and emission rates for controlled and uncontrolled sources of the targeted facilities. The data shows that the average cement consumption among the facilities is approximately 88,160 (MT/yr), with a wide range of variation depending on the facility size and production rate. The emission rates from controlled sources have an average of 4.752E-04 (g/s), while the rates from uncontrolled sources average 0.6716 (g/s). The analysis shows a significant statistical relationship (p < 0.05) and perfect positive correlation (r = 1) between cement consumption and emission rates, indicating that as cement consumption increases, emission rates tend to increase as well. Furthermore, comparing the emission rates from controlled and uncontrolled scenarios. The data showed a significant difference between the two scenarios, highlighting the effectiveness of control measures in reducing PM10 emissions. The study’s findings provide insights into the impact of cement silo emissions on air quality and the importance of implementing control measures in concrete batching facilities. The comparative analysis contributes to understanding emission sources and supports the development of pollution control strategies in the Ready-Mix industry.

The underappreciated role of fugitive VOCs in ozone formation and health risk assessment emitted from seven typical industries in China

Fugitive emission from industrial sources may result in ozone formation and health risk,while the exact contribution of this source remains incompletely understood.In this study,emission characteristics,ozone formation potential(OFP)and health risk of fugitive VOCs in7 representative industries were investigated.Chemical material industry was the dominant contributor to VOCs of fugitive emission in comparison with other industries.The OFP of VOCs from fugitive emission was in the range of 1.45×10^(3)-3.98×10^(5)μg/m^(3),with a higher value than that of organized emission in seven industries except for the coking industry and the chemical material industry,suggesting that fugitive VOCs should be taken into account while developing control strategies.Acetaldehyde,m,p-xylene,n-nonane,ethylene,vinyl chloridethe and other high OFP-contributing species were the major reactive species that should be targeted.Health risk assessment investigated non-cancer and cancer risks of fugitive VOCs in 7 industries were all above safe level(HR>1 and LCR>1×10^(-4)),posing remarkable health threats to human health.OVOCs were the main contributor to non-cancer risk,while halohydrocarbons and aromatics contributed most to cancer risks,posing remarkable health threat on human health.Our findings highlighted the contribution of fugitive VOCs on ozone formation and health risk was underestimated,indicating which should be considered in emission control strategies of industrial sources.

Exploring Win-Wins from Trade-Offs? Co-Benefits of Coalbed Methane Utilization for the Environment, Economy and Safety

With policy incentives for the coalbed methane in energy industry,coalbed methane from coal production has been effectively improved by technology innovations in coalbed methane extraction and utilization.The progress of coalbed methane promotes the clean construction of energy system and contributes to carbon neutrality target.To quantitatively measure the contributions of the coalbed methane in energy industry,this paper builds a carbon emissions accounting system for coalbed methane in China and assesses the historical co-benefits of coalbed methane utilization from the aspects of emissions reduction,safety and economy.By using the parameters of gas content,raw coal production,gas extraction rate and utilization rate over the years,emissions reduction potential and economic viability of coal seam gas are estimated and the safety benefits of coal mine gas extraction are analyzed by using data for gas accidents and economic losses.The results reveal that with the increase in raw coal production,the great emission reduction potential of coalbed methane is expected to benefit clean energy system and the development of carbon neutrality by means of policy incentives and technology innovations.The co-benefit evaluation indicates the huge profitability of coalbed methane from 2012 to 2015 and the significance of emissions reduction and safety gain internalization.Safety benefits are obvious in the negative exponential function between the annual drainage quantities of coalbed methane and annual death tolls from coal mine gas accidents.Based on these results,relevant suggestions are put forward for sustainable development of the coalbed methane in energy industry.

Underestimated contribution of fugitive emission to VOCs in pharmaceutical industry based on pollution characteristics, odorous activity and health risk assessment

Fugitive emission has been becoming an important source of volatile organic compounds(VOCs) in pharmaceutical industry,but the exact contribution of fugitive emission remains incompletely understood.In present study,pollution characteristics,odorous activity and health risk of stack and fugitive emissions of VOCs from four functional units (e.g.,workshop,sewage treatment station,raw material storage and hazardous waste storage) of three representative pharmaceutical factories were investigated.Workshop was the dominant contributor to VOCs of fugitive emission in comparison with other functional units.Extreme high concentration of VOCs from fugitive emission in unsealed workshop (94.87 mg/m^(3))was observed relative to sealed one (1.18 mg/m^(3)),accounting for 31%and 5%of total VOCs,respectively.Fugitive emission of VOCs in the unsealed workshop mainly consisted of nhexane,1-hexene and dichloromethane.Odorous activity indexes and non-cancer hazard ratios of these VOCs from fugitive emission in the unsealed workshop were as high as that from stack exhaust.Furthermore,cancer risk of dichloromethane from fugitive emission and stack exhaust was up to (1.6-1.8)×10^(-5).Odorous activity or health risk index of the VOCs from fugitive emission was up to 13 or 11 times of the corresponding threshold value,posing remarkable health threat on pharmaceutical workers.Our?ndings highlighted the possibly underestimated contribution of fugitive emission on VOCs in the pharmaceutical industry.

INFLUENCE OF AIR HUMIDITY ON THE SUPPRESSION OF FUGITIVE DUST BY USING A WATER-SPRAYING SYSTEM

One of the main origins of fugitive dust emission arises from bulk handling in quarries or mines, in particular, from bulk materials falling from a hopper or a conveyor belt. Water-spraying systems, using two-phase nozzles, are one of the methods to suppress such dust emission. In this work we tried to develop a mathematical model to correlate air humidity, water flux through the nozzle and the dust （in particular PM10） emission, in order to improve the application and efficiency of these systems. Sand from the Yellow River in China was dropped from a conveyor belt into a dust chamber at 1 kg·min^-1, wherefrom the emitted dust was sucked off and quantified via a cascade impactor. A two-phase nozzle was installed in the dust chamber with a water flux through the nozzle of 1.2 to 3 L·h^-1, whereas the relative air humidity changed between 55 and 73%. Dust emission was found to be linearly dependent on relative air humidity. Furthermore model equations were developed to describe the dependence of PM10 emission on water flux and relative air humidity.

Particulate matter characterization in a steelworks using conventional sampling and innovative lidar observations

Particulate matter （PM） emissions from steelworks cause public concern. Although end-of-pipe and pro- cess integrated measures have led to a significant drop in emissions of large particles from stacks, fine aerosols were not specifically considered, nor were emissions from fugitive and open sources. In this study, we deployed aerosol samplers together with a scanning ultra-violet （UV） lidar to characterize total suspended particles （TSP）, PM10, and PM2.5, in emissions from a large integrated steelworks in Spain over a 16-day period. We determined the content of carbonaceous, soluble inorganic, mineral dust, and metal species. A positive matrix factorization was carried out on our dataset. Despite mineral dust being predominant in all size fractions, the steelworks was clearly a source of carbonaceous species, resulting in production of secondary inorganic aerosols. In particular, stack emissions were a major contributor of fine particles, while open sources dominated the emissions of TSP, yielding up to 80% of particles larger than PM10. UV lidar provided 2D maps of aerosols in real time, with an ability to detect PM emissions and to visualize complex plumes. We suggest that air quality management of steelworks needs to focus on controlling large and coarse oarticle emissions, esoeciallv those from onen sources.