VOC Emissions Research Articles

Integrated empirical and modelled determination of the human health impacts of building material VOCs

• Material VOC emission data points are extrapolated with an emission model. • Model calibration allows to fix parameters (diffusion and material-air partition coefficients). • Full exposure profiles are obtained and allow the evaluation of health impacts on building occupants. • Impacts related to gypsum wall VOC off-gassing amounts to 62 μDALY for a 15 m 2 office.

Emission Inventory of Airborne Pollutants from Biomass Combustion in Guizhou Province

With the objective to ascertain the emissions of biomass combustion in Guizhou, the activity levels were measured through data collection and field surveys, and the emission factors were acquired using actual monitoring data and data cited from previous literature. A 3 km×3 km-gridded emission inventory of nine air pollutants from biomass combustion sources in Guizhou Province in 2019 was developed in combination with GIS technology. The results showed that the total emissions of CO, NOx, SO2, NH3, VOCs, PM2.5, PM10, BC, and OC in Guizhou were estimated to be 293505.53, 14781.19, 4146.11, 8501.07, 45025.70, 39463.58, 41879.31, 6832.33, and 15134.74 t, respectively. The distribution of atmospheric pollutants emitted by biomass combustion sources in different cities was noticeably uneven, being mainly concentrated in Qiandongnan Miao and Dong Autonomous Prefecture. The analysis of variation characteristics of emissions indicated that the monthly emissions were concentrated in February, March, April, and December, and the hourly emissions peaked daily from 14:00 to 15:00. Some uncertainty remained in the emission inventory. It is necessary to perform in-depth analyses of the accuracy of obtaining activity-level data, localize the emission factors through more combustion experiments in subsequent research for improving the emission inventory of air pollutants from biomass combustion in Guizhou Province, and provide a basis for the cooperative governance of the atmospheric environment.

Assessment of Emission Reduction Effect of Major Air Pollution Control Measures on PM2.5 Concentrations During 13th Five-Year Period in Tianjin

The emission reduction effect of major air pollution control measures on PM2.5 concentrations was assessed using air quality simulations based on the calculation data of emission reductions from different air pollution control measures and the high spatiotemporal resolution online monitoring data of PM2.5 during the 13th Five-Year Period in Tianjin. The results showed that the total emission reductions of SO2, NOx, VOCs, and PM2.5 from 2015 to 2020 were 4.77×104, 6.20×104, 5.37×104, and 3.53×104 t, respectively. SO2 emission reduction was mainly due to the prevention of process pollution, loose coal combustion, and thermal power. NOx emission reduction was mainly due to the prevention of process pollution, thermal power, and steel industry. VOCs emission reduction was mainly due to prevention of process pollution. PM2.5 emission reduction was mainly due to the prevention of process pollution, loose coal combustion, and the steel industry. The concentrations, pollution days, and heavy pollution days of PM2.5 decreased significantly from 2015 to 2020 by 31.4%, 51.2%, and 60.0% compared to those in 2015, respectively. The concentrations and pollution days of PM2.5 decreased slowly in the later stage (from 2018 to 2020)as compared with those in the early stage (from 2015 to 2017), and the days of heavy pollution remained for approximately 10 days. The results of air quality simulations showed that meteorological conditions contributed one-third to the reduction in PM2.5 concentrations, and the emission reductions of major air pollution control measures contributed two-thirds to the reduction in PM2.5 concentrations. For all air pollution control measures from 2015 to 2020, PM2.5 concentrations were reduced by the prevention of process pollution, loose coal combustion, the steel industry, and thermal power by 2.66, 2.18, 1.70, and 0.51 μg·m-3, respectively, accounting for 18.3%, 15.0%, 11.7%, and 3.5% of PM2.5 concentration reductions. In order to promote the continuous improvement in PM2.5 concentrations during the 14th Five-Year Plan period, under the total coal consumption control and the goal of "peaking carbon dioxide emissions and achieving carbon neutrality," Tianjin should continue to optimize and adjust the coal structure and further promote the coal consumption to the power industry with an advanced pollution control level. At the same time, it is necessary to further improve the emission performance of industrial sources in the whole process, taking environmental capacity as the constraint; design the technical route for industrial optimization, adjustment, transformation, and upgrading; and optimize the allocation of environmental capacity resources. Additionally, the orderly development model for key industries with limited environmental capacity should be proposed, and clean upgrading, transformation, and green development should be guided for enterprises.

Emission and Mechanical Properties of Glass and Cellulose Fiber Reinforced Bio-Polyamide Composites.

Climate change, access, and monopolies to raw material sources as well as politically motivated trade barriers are among the factors responsible for a shortage of raw materials. In the plastics industry, resource conservation can be achieved by substituting commercially available petrochemical-based plastics with components made from renewable raw materials. Innovation potentials are often not used due to a lack of information on the use of bio-based materials, efficient processing methods, and product technologies or because the costs for new developments are too high. In this context, the use of renewable resources such as fiber-reinforced polymeric composites based on plants has become an important criterion for the development and production of components and products in all industrial sectors. Bio-based engineering thermoplastics with cellulose fibers can be used as substitutes because of their higher strength and heat resistance, but the processing of this composite is still challenging. In this study, composites were prepared and investigated using bio-based polyamide (PA) as a polymer matrix in combination with a cellulosic fiber and, for comparison purposes, a glass fiber. A co-rotating twin-screw extruder was used to produce the composites with different fiber contents. For the mechanical properties, tensile tests and charpy impact tests were performed. Compared to glass fiber, reinforced PA 6.10 and PA 10.10, a significantly higher elongation at break with regenerated cellulose fibers, can be achieved. PA 6.10 and PA 10.10 achieve significantly higher impact strengths with the regenerated cellulose fibers than the composites with glass fibers. In the future, bio-based products will also be used in indoor applications. For characterization, the VOC emission GC-MS analysis and odor evaluation methods were used. The VOC emissions (quantitative) were at a low level but the results of the odor tests of selected samples showed values mostly above the required limit values.

Evolution of coalescent agent-free ultra-low VOC paint with formaldehyde capturing properties

The majority of people spend a significant portion of their waking lives indoors, they are continually exposed to a higher concentration of indoor air pollutants. As new technologies emerge and more people become aware of the issue, it has become crucial to discover new methods for cleaning up polluted indoor air and minimizing people's exposure to it.This research aims to develop a waterborne, low-VOC, formaldehyde-capturing formulation for interior paint. In paint formulation, biocides, coalescing agents, ammonia, binders, and liquid phase additives are all possible sources of volatile organic compounds. In this study, formulations of coalescing agent-free and formaldehyde-free waterborne coatings with high performance characteristics and ultra-low VOC content were created by chemically adsorbing formaldehyde using an active ingredient. The colorimetric method, which is developed based on the color concentration change, and the cabin method test methods, which monitor the change of formaldehyde concentration in the interior environment, were developed within the scope of the study in order to test the effect of the product. The final formulation complies with the A + French VOC labeling and the Indoor Air Comfort Gold criteria for VOC emissions, and tests demonstrated an 87% decrease in ambient formaldehyde concentrations within 24 h of application (ISO 16000–9:2006, EN 16516:2017).

Emission trends of air pollutants and CO2 in China from 2005 to 2021

Abstract. China is facing the challenge of synergistic reduction of air pollutants and CO2 emissions. However, the studies on its historical progress and future priorities are insufficient. This study compiled China's emission inventory of air pollutants and CO2 from 2005 to 2021 (ABaCAS-EI v2.0 dataset) based on a unified emission-source framework by considering the influences of activity level, technology evolution, and emission control policies. The characteristics of air pollutants and CO2 emissions were comprehensively analyzed from multiple dimensions such as time, space, sector, and synergies between air pollutants and CO2 emissions. Mitigation policies have decoupled the emissions of air pollutants and CO2 with economic development in China since 2013. In the context of growing activity levels, energy structure adjustment and energy and material saving reduced the average annual increase rate of CO2 emissions by 7 % after 2011. Based on this, end-of-pipe control contributed 51 %–98 % of air pollutant emission reductions after 2013. Industrial boilers and residential fossil fuel combustion sectors in seven provinces (Beijing, Tianjin, Shanghai, Jilin, Henan, Sichuan, and Qinghai) achieved emission reductions in both air pollutants and CO2 during 2013–2021. The declining trends in both the sectoral and regional emission ratios of air pollutants to CO2 indicated that the potential for synergistic emission reduction in China declined from 2013 to 2021. The emission ratios in 2021 showed that residential fossil fuel combustion, iron and steel industry, and transportation exhibited relatively higher co-benefits of SO2, PM2.5, NOx, and VOC emission reductions when CO2 emissions were reduced. Most cities with a higher potential to synergistically reduce NOx, VOC, and CO2 emissions were within the Yangtze River Economic Belt, while those with a higher potential to co-control SO2 and CO2, and PM2.5 and CO2 were in southern and northeast China, respectively. Further deconstruction of the sectoral emissions in 2021 suggested future reduction measures: for example, controlling coal consumption in the energy field; promoting innovative technologies with low air pollutant emission intensities and coal-saving measures in the iron and steel industry; combining coal and carbonate replacement technologies with separated particle control measures in the cement industry; and controlling light-duty passenger vehicles, heavy-duty trucks, agricultural machinery, and inland water transport in the transportation sector. Our dataset and findings provide insights into the co-control of air pollutants and CO2 emissions in the future in China and other countries with the same demand. Our ABaCAS-EI v2.0 dataset can be accessed from https://doi.org/10.6084/m9.figshare.21777005.v1 (S. Li et al., 2022) by species, sector, and province.

Open-path dual-comb spectroscopy of methane and VOC emissions from an unconventional oil well development in Northern Colorado.

We present results from a field study monitoring methane and volatile organic compound emissions near an unconventional oil well development in Northern Colorado from September 2019 to May 2020 using a mid-infrared dual-comb spectrometer. This instrument allowed quantification of methane, ethane, and propane in a single measurement with high time resolution and integrated path sampling. Using ethane and propane as tracer gases for methane from oil and gas activity, we observed emissions during the drilling, hydraulic fracturing, millout, and flowback phases of well development. Large emissions were seen in drilling and millout phases and emissions decreased to background levels during the flowback phase. Ethane/methane and propane/methane ratios varied widely throughout the observations.

Composition for concentrated powder color with gradient color effect and color matching

A dry coating substance was applied using the powder coating method of dry finishing. The coating substance consists of finely ground resin particles, color pigments, and additional additives for particular purposes like gloss or hardness. Powder coating compositions typically include a thermosetting resin that forms a solid film and one or more pigments. However, they can also be thermoplastic. The requirement to comprehend the characteristics and uses of powder coatings as an alternative to conventional liquid coatings is stated as the difficulty. The article discusses the drawbacks of liquid coatings, including their high VOC emissions and negative environmental effects, as well as the advantages of powder coatings, including their lower environmental impact and less waste.The necessity to investigate and comprehend the potential of powder coatings as an alternative to conventional liquid coatings, as well as to give a thorough evaluation of their features and uses, constitutes the article's overall issue statement. This research has compared several published research papers, referred to those, and concluded to make changes in the existing process such as removing manufacturing process i.e Extrusion, and changes in the composition. It was observed that the existing composition lacks certain properties like Abrasion, Impact and Marking/Mar Resistance, and Chemical Resistance. The salt spray test was ineffective as well. A salt spray test was conducted for 240 Hours with 50 g of sodium chloride per liter of distilled water which was successful in the obtained and new composition. Changes were made in the concentration percentage of resin and crosslinker. A new component called filler, manufactured by Solvay and named it Blanc fixen, was used in the manufacturing process.

An Observational Constraint of VOC Emissions for Air Quality Modeling Study in the Pearl River Delta Region

AbstractVolatile organic compounds (VOCs) have crucial influences on atmospheric chemistry. Accurate quantification of the VOC emissions is critical for air pollution research, especially when applying to air quality models. However, current bottom‐up emission inventories have biases, making observational constraints of VOC emissions necessary. We conducted concurrent VOC measurements in the Pearl River Delta (PRD) region during the summer of 2018 and found large discrepancies in the spatiotemporal variations of VOCs between observations and model simulations when using the priori VOC emission inventory (Multi‐resolution Emission Inventory for China). The normalized biases of total VOC concentrations ranged from −55% to 85% across the PRD cities in the study period. To improve the simulations, we constrained the anthropogenic VOC emissions based on their measured concentrations. The observation‐constrained VOC emissions showed clear diurnal variations and resolved the spatially‐concentrated priori emissions by reducing the high emissions by 15%–36% in the central PRD cities while elevating the sparse emissions in other cities. After employing the observation‐constrained VOC emissions, the model better reproduced the spatiotemporal variations of VOCs in the PRD region, alleviating the biases to −13%–13%. Furthermore, simulations of peak ozone (O3) concentrations were amended to reduce the mean normalized bias by 5%–12% on high O3 days. Our work has effectively combined VOC field measurements with air quality modeling to achieve better simulations of VOCs and O3. Besides, the observational‐constrained emissions are flexible for studying short‐term emission changes and their subsequent impacts on air quality.

Analytical solution for one‐dimensional steady‐state VOCs diffusion in simplified capillary cover systems

AbstractThe analytical solution for a one‐dimensional and steady‐state model is proposed to investigate the diffusion of VOCs within landfill capillary cover systems under unsaturated water flow and stable conditions. Examples of coupled water flow and VOCs diffusion are evaluated by the proposed analytical solution to discuss the effects of the evaporation rate and clay thickness. The proficiency of the unsaturated cover system in minimising VOC emissions was also investigated. It was found that the non‐uniform distribution of water content can cause one order of magnitude reductions in the effective diffusion coefficient of VOCs, resulting in the attenuation of VOCs in the cover system. The concentration profile of VOCs is lower for the case with a larger evaporation rate. Ignoring the non‐uniform distribution of water content induced by water flow would underestimate the surface flux of VOCs by a factor of 1.8. The water content and VOC concentration in the cover system can be effectively diminished with the thickness of the clayey layer increasing. The surface flux of VOCs is considerably decreased with increasing thickness of clayey layer. Increasing the thickness of clayey layer from 0.2 to 1 m leads to a reduction in the surface flux of VOCs by a factor of 2.9. The sensitivity analysis provides further insights into the critical role of water flow in affecting VOC transport through the unsaturated cover system. The outcomes highlight that the impacts of unsaturated water flow within the covering system should be considered for assessment of VOC emissions.

Antifungal activity of volatile and non-volatile metabolites of endophytes of Chloranthus elatior Sw.

Agriculture crops that have fungal infections suffer significant economic losses and reduced crop output. Chemical fungicides are used to tackle the problem, although this has additional detrimental side effects. There is an urgent need for safe and novel antifungals. Volatiles from plant-beneficial endophytic fungi are considered promising alternatives for the biological control of fungal pathogens as a sustainable approach in an agroecosystem. In the present investigation, a volatile-emitting sterile endophytic fungus, Diaporthe sp. CEL3 with bio-fumigation activity, was isolated from leaves of the ethnomedicinal plant Chloranthus elatior Sw., collected from the Passighat forest of North-East India. The camphor odor volatiles of CEL3 showed an inhibitory effect against eight fungal pathogens in vitro and minimized the infections of Monilinia fructicola, a causal agent of cherry fruit rot, in VOC-exposed cherry fruits. Rhizoctonia solani, Botrytis cinerea, Pythium ultimum, and M. fructicola were maximally inhibited up to 51.5%, 55.8%, 61.9%, and 78.5%, respectively, in comparison to control by the volatiles. Another isolate, CEL7, identified as Curvularia sp., synthesized non-volatile, soluble antifungal metabolites in its cell-free extracts and exhibited antifungal action. Bioassay-guided fractionation revealed the presence of imidazole compounds- (2-aminoethyl)-1H-imidazole-2-carbaldehyde, Pyrazole 4, 5 imidazole, 1-formyl 3-ethyl, phenol compounds-Phenol, 4-[2-(methylamino) ethyl]-, 6-Nitro-3-chlorophenol, Phenol, 2,4,6-tri-tert-butyl-, etc., in the cell-free extracts, with a MIC value of 250-2,000 µg ml-1. Optimum VOC emission was achieved in a modified PDA medium with instantly smashed potato (150 g L-1), dextrose (20 g L-1), wheat husk (20 g L-1), and yeast extract (20 g L-1), with additional salts. Interestingly, endophytic CEL3 emitted different types of volatiles, and trans-verbenol (32.25%), geraniol (30.32%), trans-ocimenol (12.90%), and mentha-4,8-diene (5.16%) were the prime ones. These VOCs cause lethal leakage of protein and necessary intracellular molecules from the fungal pathogens. Thus, CEL3 could potentially be used as a bio-fumigating agent to control post-harvest infections caused by fungal pathogens. This study opens a new approach to the use of endophytic fungi in biocontrol.

Unequal Health Risks of Integrated Volatile Organic Compounds Emitted From Various Anthropogenic Sources

AbstractVolatile organic compounds (VOCs) emitted from anthropogenic sources are critical precursors to ozone and secondary organic aerosol (SOA), and potential contributors to health risks. However, quantitatively estimating the impact of these source‐derived VOCs on air quality and health is limited by their diverse chemical compositions, resulting in nonselective mass‐based VOC control strategies. To address this issue, we conducted a comprehensive study of typical VOC samples freshly emitted from various flue gases via field‐based measurements and chemical analysis under the same quality control. Our results showed that different source‐specific VOC profiles have unequal sensitivities to chemical reactivity on ozone and SOA formation potential, as well as potential health risks. Mobile sources and residential solid fuel burning were identified as the most sensitive sources of potential secondary pollutants and potential inhalation health risks, respectively. Despite accounting for only 22.7% of the total mass, residential VOCs contributed significantly to both inhalation non‐cancer risk (NCR) (57.4%) and cancer risk (CR) (47.3%). The large inequality between residential VOC emissions and their health risks highlights the necessity of continuously promoting the transition from mass‐based VOC control to effect‐oriented VOC control. This suggests that mobile sources is worth more attention for secondary pollutant formation, while residential solid fuel burning sources should receive more policy priority to reduce health risks.

Ozone response modeling to NOx and VOC emissions: Examining machine learning models

Current machine learning (ML) applications in atmospheric science focus on forecasting and bias correction for numerical modeling estimations, but few studies examined the nonlinear response of their predictions to precursor emissions. This study uses ground-level maximum daily 8-hour ozone average (MDA8 O3) as an example to examine O3 responses to local anthropogenic NOx and VOC emissions in Taiwan by Response Surface Modeling (RSM). Three different datasets for RSM were examined, including the Community Multiscale Air Quality (CMAQ) model data, ML-measurement-model fusion (ML-MMF) data, and ML data, which respectively represent direct numerical model predictions, numerical predictions adjusted by observations and other auxiliary data, and ML predictions based on observations and other auxiliary data.The results show that both ML-MMF (r = 0.93–0.94) and ML predictions (r = 0.89–0.94) present significantly improved performance in the benchmark case compared with CMAQ predictions (r = 0.41–0.80). While ML-MMF isopleths exhibit O3 nonlinearity close to actual responses due to their numerical base and observation-based correction, ML isopleths present biased predictions concerning their different controlled ranges of O3 and distorted O3 responses to NOx and VOC emission ratios compared with ML-MMF isopleths, which implies that using data without support from CMAQ modeling to predict the air quality could mislead the controlled targets and future trends. Meanwhile, the observation-corrected ML-MMF isopleths also emphasize the impact of transboundary pollution from mainland China on the regional O3 sensitivity to local NOx and VOC emissions, which transboundary NOx would make all air quality regions in April more sensitive to local VOC emissions and limit the potential effort by reducing local emissions.Future ML applications in atmospheric science like forecasting or bias correction should provide interpretability and explainability, except for meeting statistical performance and providing variable importance. Assessment with interpretable physical and chemical mechanisms and constructing a statistically robust ML model should be equally important.

Physicochemical Assessment of the Road Vehicle Traffic Pollution Impact on the Urban Environment

Vehicle traffic pollution requires complex physicochemical analysis besides emission level measuring. The current study is focused on two campaigns of emissions measurements held in May and September 2019 in Alba Iulia City, Romania. There was found a significant excess of PM2.5 for all measuring points and PM10 for the most circulated points during May, along with significant VOC and CO2 emissions. September measurements reveal threshold excess for all PM along with increased values for VOC and CO2 emissions. These are the consequences of the complex environmental interaction of the traffic. Street dust and air-suspended particle samples were collected and analyzed to evidence the PM2.5 and PM10 sources. Physicochemical investigation reveals highly mineralized particulate matter: PM2.5 fractions within air-suspended particle samples predominantly contain Muscovite, Kaolinite, and traces of Quartz and Calcite, while PM10 fractions within air-suspended particle samples predominantly contain Quartz and Calcite. These mineral fractions originate in street dust and are suspended in the atmosphere due to the vehicles’ circulation. A significant amount of soot was found as small micro-sized clusters in PM2.5 and fine micro-spots attached over PM10 particles, as observed by Mineralogical Optical Microscopy (MOM) and Fourier Transformed Infrared Spectroscopy (FTIR). GC-MS analysis found over 53 volatile compounds on the investigated floating particles that are related to the combustion gases, such as saturated alkanes, cycloalkanes, esters, and aromatic hydrocarbons. It proves a VOC contamination of the measured particulate matters that make them more hazardous for the health. Viable strategies for vehicle traffic-related pollutants mitigation would be reducing the street dust occurrence and usage of modern catalyst filters of the combustion gas exhausting system.

43 Particle and VOC Emissions During the Thermal Processing of Plastics to make Filaments for 3D-Printing

Abstract Introduction 3D-printing is continuing to grow as an industry, which creates a demand for printing material. Studies on 3D-printing have shown that printers emit nanoparticles and VOC, depending on printing method, and some adverse health effects have been reported. Emissions during production of 3D-printer filament is less studied, and interesting as it can be likened to a larger material extrusion printer. Materials and methods Measurements were made at a factory producing 3D-printer filaments, using an array of instruments to characterise the emissions and exposure for the staff. Particle emissions were assessed using condensation particle counters (20nm-1um), DataRAM (0.1-10 um) and a particle sensor (0.35-40 um). VOC emissions and exposure were assessed using Tenax tubes and VOC sensors. Measurements were performed for 1-2 days, apart from sensors, which were placed at the facility for a full working week, including after a longer break . Results High concentrations of nanoparticles were found in the production rooms (25 000-100 000 pt/ml) and close to the extruder nozzle (100 000-500 000 pt/ml). Levels of nanoparticles were also high in office rooms near production(25 000-50 000 pt/ml). VOC sensors showed the same trend in all rooms, including offices and staff kitchen, indicating spread of emissions from the source and inadequate ventilation. The particle sensor also showed variation over the week in correlation with work performed. Conclusion Production of 3D-printer filaments emit nanoparticles and VOC. Inadequate ventilation can lead to high concentrations of nanoparticles. Sensors were a useful tool to show emission trends.

An animal glycerol potassium salt without volatile organic compounds emission combined with plasma‐atomization technology and its application in green tires

AbstractIn this study, a VOC‐free animal glycerol potassium salt is introduced to replace the silane coupling agent, and the plasma is used to treat the modifier and silica. The impact of high‐energy electrons in the plasma increases the contact area between the modifier and silica. Combined with the atomization technology, the velocity difference realizes the microscopic dispersion of silica, the instantaneous thin‐layer drying reduces the oxidation of the rubber chains. XPS and SEM show that the plasma promotes the silanization reaction of silica. FTIR demonstrates that the existence of chemical bonds and hydrogen bonds between potassium oleate (PO) and silica, and there is a crosslinking between PO and sulfur. The PO/Si69‐silica/NR composites prepared by plasma‐atomization technology have better processing fluidity, mechanical properties and lower rolling resistance. The plasma‐atomization technology promotes the silanization reaction of silica, saves energy consumption and reduces dust pollution, meanwhile, the replacement of Si69 by PO reduces VOC emissions and the rolling resistance of the rubber, which provides an innovative idea for the development of green tires.

Comparison of ozonesonde measurements in the upper troposphere and lower Stratosphere in Northern India with reanalysis and chemistry-climate-model data

The variability and trend of ozone (O3) in the Upper troposphere and Lower Stratosphere (UTLS) over the Asian region needs to be accurately quantified. Ozone in the UTLS radiatively heats this region and cools the upper parts of the stratosphere. This results in an impact on relative humidity, static stability in the UTLS region and tropical tropopause temperature. A major challenge for understanding ozone chemistry in the UTLS is sparse observations and thus the representation of precursor gases in model emission inventories. Here, we evaluate ozonesonde measurements during August 2016 at Nainital, in the Himalayas, against ozone from multiple reanalyses and the ECHAM6-HAMMOZ model. We find that compared to measurements both reanalyses and ECHAM6-HAMMOZ control simulation overestimate ozone mixing ratios in the troposphere (20 ppb) and in the UTLS (55 ppb). We performed sensitivity simulations using the ECHAM6-HAMMOZ model for a 50% reduction in the emission of (1) NOx and (2) VOCs. The model simulations with NOX reduction agree better with the ozonesonde observations in the lower troposphere and in the UTLS. Thus, neither reanalyses nor ECHAM6-HAMMOZ results can reproduce observed O3 over the South Asian region. For a better representation of O3 in the ECHAM6-HAMMOZ model, NOX emission should be reduced by 50% in the emission inventory. A larger number of observations of ozone and precursor gases over the South Asian region would improve the assessment of ozone chemistry in models.

Volatile organic compounds losses simulation during storage of gasoline

This article analyses the simulation of evaporative VOCs losses from storage tanks of gasoline and its anti-knock additives using TANKS 409d software. The VOCs emissions were estimated for different types of storage tanks: internal floating roof tank (IFRT), external floating roof tank (EFRT) from the one tank farmer of Romanian oil company. The obtained results show quantities of evaporated losses of fugitive VOCs emission approximately 165 t annually, between 01 August 2021 – 31 July 2022. The hazard evaluation of some components (toluene and anti-knock additives) from commercial gasoline has done by the computerize tool ALOHA in different scenarios during the operation of storage tanks. Using MARPOL application software, the pollutant threat zone has been mapped from ALOHA Gaussian model application.

A Study on the Investigation of Air Pollutant Emissions (2015~2019) in Gunsan

Objectives : In this study, the emission status by year was analyzed using the air pollutant emission data of Gunsan for 5 years from 2015 to 2019. In addition, it is intended to identify the emission characteristics of (Jeonju and Iksan).Methods : Using the air pollutant emission data of the Clean Air Policy Support System(CAPSS) provided by the Ministry of Environment's National Fine Dust Information Center, the status of air pollutant emissions(CO, NOx, SOx, PM10, VOCs, NH3) in Gunsan was analyzed.Results and Discussion : In Gunsan, CO(car registration number), PM10(cargo transport volume) NH3(farmland using fertilizer, manure management) emissions increased. NOx(production of glass products) SOx{glass (carbon removal process)} and VOCs(whiskey, etc) emissions were reduced. In the emission characteristics, CO and NOx are mainly road transport and non-road transport pollutants(leisure, cargo) and SOx is production process{glass(carbon removal process)} and energy industry combustion(private power plant). PM10 is a non-road moving pollutant(ship, cargo), scattering dust(road scattering dust, construction work, agriculture), and VOCs are food and beverage processing(whiskey, etc) and organic solvent in the production process painting facility (ship manufacturing). NH3 is agricultural(fertilized cropland, manure management) and production processes(ammonia consumption). In the comparison of emission characteristics, Gunsan(CO, NOx, SOx, VOCs), Jeonju(PM10), Iksan(NH3) were high.Conclusion : The emission rate of air pollutants in Gunsan was in the order of VOCs > NOx > CO > SOx > NH3 > PM10. In the comparison of emissions characteristics, Gunsan, Jeonju and Iksan showed the same in NOx and NH3, but different in CO, SOx, PM10 and VOCs characteristics. This case is considered to be influenced by the size of the industrial complex, geographical characteristics of the region, economic structure, and population.

Unexpected deterioration of O3 pollution in the South Coast Air Basin of California: The role of meteorology and emissions

Tropospheric ozone (O3) pollution has long been a prominent environmental threat due to its adverse impacts on vulnerable populations and ecosystems. In recent years, an unexpected increase in O3 levels over the South Coast Air Basin (SoCAB) of California has been observed despite reduced precursor emissions and the driving factors behind this abnormal condition remain unclear. In this work, we combine ambient measurements, satellite data, and air quality modeling to investigate O3 and precursor emission trends and explore the impacts of meteorological variability and emission changes on O3 over the SoCAB from 2012 to 2020. Changes in O3 trends were characterized by declining O3 in 2012–2015, and increasing O3 afterwards with the most extreme O3 exceedances in 2020. Basin-wide increases of MDA8 O3 concentrations over warm season were depicted between 2012 and 2020, with the most significant enhancements (5–10 ppb) observed in San Bernardino County. Persistent heatwaves and weak ventilation on consecutive days were closely correlated with O3 exceedances (r2 above 0.6) over inland SoCAB. While decreasing trends in NOx (−4.1%/yr) and VOC emissions (−1.8%/yr) inferred from emission inventory and satellites during 2012–2020 resulted in a slow transition for O3 sensitivity from VOCs-limited to NOx-limited, model simulations performed with fixed meteorology indicate that unfavorable meteorological conditions could largely offset regulation benefits, with meteorology anomaly-induced monthly O3 changes reaching 20 ppb (May 2020) and the deterioration of O3 pollution in 2016, 2017, and 2020 was largely attributed to unfavorable meteorological conditions. Nevertheless, anthropogenic emission changes may act as the dominant factor in governing O3 variations across the SoCAB when net effects of meteorology are neutral (typically 2018). This work provides a comprehensive assessment of O3 pollution and contributes valuable insights into understanding the long-term changes of O3 and precursors in guiding future regulation efforts in the SoCAB.