Academic literature on the topic 'Non-methane volatile organic compounds (NMVOCs)'
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Journal articles on the topic "Non-methane volatile organic compounds (NMVOCs)"
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Lanz, V. A., S. Henne, J. Staehelin, C. Hueglin, M. K. Vollmer, M. Steinbacher, B. Buchmann, and S. Reimann. "Statistical analysis of anthropogenic non-methane VOC variability at a European background location (Jungfraujoch, Switzerland)." Atmospheric Chemistry and Physics 9, no. 10 (May 28, 2009): 3445–59. http://dx.doi.org/10.5194/acp-9-3445-2009.
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Abstract. In-situ measurements of 7 volatile hydrocarbons, CxHy, and 3 chlorinated organic compounds, CxHyClz, were performed at Jungfraujoch (Switzerland) during eight years (2000–2007). The analysis of 4-h resolved non-methane volatile organic compounds (NMVOCs) was achieved by using gas-chromatography coupled with mass spectrometry (GC-MS). Variabilities in the NMVOC time series dataset were modeled by factor analysis (positive matrix factorization, PMF). Four factors defined the solution space and could be related to NMVOC sources and atmospheric processes. In order to facilitate factor interpretations the retrieved contributions were compared with independent measurements, such as trace gases (NOx, CO, and CH4) and back trajectories. The most dominant factor (accounting on average for ~42% of the total mixing ratio of the considered NMVOCs) was found to be most active in winter, co-varying with CO and CH4 and could be related to aged combustive emissions as well as natural gas distribution. The other three factors represent both industrial and evaporative sources. Trajectory statistics suggest that the most influential anthropogenic NMVOC sources for Jungfraujoch are located in Eastern Europe, but the Po Valley has been identified as a potential source region for specific industrial sources as well. Aging of the arriving NMVOCs, the derived factors as well as limitations of the methods are discussed. This is the first report of a PMF application on NMVOC data from a background mountain site.
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Fry, M. M., M. D. Schwarzkopf, Z. Adelman, and J. J. West. "Air quality and radiative forcing impacts of anthropogenic volatile organic compound emissions from ten world regions." Atmospheric Chemistry and Physics 14, no. 2 (January 16, 2014): 523–35. http://dx.doi.org/10.5194/acp-14-523-2014.
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Abstract. Non-methane volatile organic compounds (NMVOCs) influence air quality and global climate change through their effects on secondary air pollutants and climate forcers. Here we simulate the air quality and radiative forcing (RF) impacts of changes in ozone, methane, and sulfate from halving anthropogenic NMVOC emissions globally and from 10 regions individually, using a global chemical transport model and a standalone radiative transfer model. Halving global NMVOC emissions decreases global annual average tropospheric methane and ozone by 36.6 ppbv and 3.3 Tg, respectively, and surface ozone by 0.67 ppbv. All regional reductions slow the production of peroxyacetyl nitrate (PAN), resulting in regional to intercontinental PAN decreases and regional NOx increases. These NOx increases drive tropospheric ozone increases nearby or downwind of source regions in the Southern Hemisphere (South America, Southeast Asia, Africa, and Australia). Some regions' NMVOC emissions contribute importantly to air pollution in other regions, such as East Asia, the Middle East, and Europe, whose impact on US surface ozone is 43%, 34%, and 34% of North America's impact. Global and regional NMVOC reductions produce widespread negative net RFs (cooling) across both hemispheres from tropospheric ozone and methane decreases, and regional warming and cooling from changes in tropospheric ozone and sulfate (via several oxidation pathways). The 100 yr and 20 yr global warming potentials (GWP100, GWP20) are 2.36 and 5.83 for the global reduction, and 0.079 to 6.05 and −1.13 to 18.9 among the 10 regions. The NMVOC RF and GWP estimates are generally lower than previously modeled estimates, due to the greater NMVOC/NOx emissions ratios simulated, which result in less sensitivity to NMVOC emissions changes and smaller global O3 burden responses, in addition to differences in the representation of NMVOCs and oxidation chemistry among models. Accounting for a fuller set of RF contributions may change the relative magnitude of each region's impacts. The large variability in the RF and GWP of NMVOCs among regions suggest that regionally specific metrics may be necessary to include NMVOCs in multi-gas climate trading schemes.
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Fry, M. M., M. D. Schwarzkopf, Z. Adelman, and J. J. West. "Air quality and radiative forcing impacts of anthropogenic volatile organic compound emissions from ten world regions." Atmospheric Chemistry and Physics Discussions 13, no. 8 (August 13, 2013): 21125–57. http://dx.doi.org/10.5194/acpd-13-21125-2013.
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Abstract. Non-methane volatile organic compounds (NMVOCs) influence air quality and global climate change through their effects on secondary air pollutants and climate forcers. Here we simulate the air quality and radiative forcing (RF) impacts of changes in ozone, methane, and sulfate from halving anthropogenic NMVOC emissions globally and from 10 regions individually, using a global chemical transport model and a standalone radiative transfer model. Halving global NMVOC emissions decreases global annual average tropospheric methane and ozone by 36.6 ppbv and 3.3 Tg, respectively, and surface ozone by 0.67 ppbv. All regional reductions slow the production of PAN, resulting in regional to intercontinental PAN decreases and regional NOx increases. These NOx increases drive tropospheric ozone increases nearby or downwind of source regions in the Southern Hemisphere (South America, Southeast Asia, Africa, and Australia). Some regions' NMVOC emissions contribute importantly to air pollution in other regions, such as East Asia, Middle East, and Europe, whose impact on US surface ozone is 43%, 34%, and 34% of North America's impact. Global and regional NMVOC reductions produce widespread negative net RFs (cooling) across both hemispheres from tropospheric ozone and methane decreases, and regional warming and cooling from changes in tropospheric ozone and sulfate (via several oxidation pathways). The total global net RF for NMVOCs is estimated as 0.0277 W m−2 (~1.8% of CO2 RF since the preindustrial). The 100 yr and 20 yr global warming potentials (GWP100, GWP20) are 2.36 and 5.83 for the global reduction, and 0.079 to 6.05 and −1.13 to 18.9 among the 10 regions. The NMVOC RF and GWP estimates are generally lower than previously modeled estimates, due to differences among models in ozone, methane, and sulfate sensitivities, and the climate forcings included in each estimate. Accounting for a~fuller set of RF contributions may change the relative magnitude of each region's impacts. The large variability in the RF and GWP of NMVOCs among regions suggest that regionally-specific metrics may be necessary to include NMVOCs in multi-gas climate trading schemes.
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Huang, Ganlin, Rosie Brook, Monica Crippa, Greet Janssens-Maenhout, Christian Schieberle, Chris Dore, Diego Guizzardi, Marilena Muntean, Edwin Schaaf, and Rainer Friedrich. "Speciation of anthropogenic emissions of non-methane volatile organic compounds: a global gridded data set for 1970–2012." Atmospheric Chemistry and Physics 17, no. 12 (June 26, 2017): 7683–701. http://dx.doi.org/10.5194/acp-17-7683-2017.
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Abstract. Non-methane volatile organic compounds (NMVOCs) include a large number of chemical species which differ significantly in their chemical characteristics and thus in their impacts on ozone and secondary organic aerosol formation. It is important that chemical transport models (CTMs) simulate the chemical transformation of the different NMVOC species in the troposphere consistently. In most emission inventories, however, only total NMVOC emissions are reported, which need to be decomposed into classes to fit the requirements of CTMs. For instance, the Emissions Database for Global Atmospheric Research (EDGAR) provides spatially resolved global anthropogenic emissions of total NMVOCs. In this study the EDGAR NMVOC inventory was revised and extended in time and in sectors. Moreover the new version of NMVOC emission data in the EDGAR database were disaggregated on a detailed sector resolution to individual species or species groups, thus enhancing the usability of the NMVOC emission data by the modelling community. Region- and source-specific speciation profiles of NMVOC species or species groups are compiled and mapped to EDGAR processes (detailed resolution of sectors), with corresponding quality codes specifying the quality of the mapping. Individual NMVOC species in different profiles are aggregated to 25 species groups, in line with the common classification of the Global Emissions Initiative (GEIA). Global annual grid maps with a resolution of 0.1° × 0.1° for the period 1970–2012 are produced by sector and species. Furthermore, trends in NMVOC composition are analysed, taking road transport and residential sources in Germany and the United Kingdom (UK) as examples.
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Stewart, Gareth J., W. Joe F. Acton, Beth S. Nelson, Adam R. Vaughan, James R. Hopkins, Rahul Arya, Arnab Mondal, et al. "Emissions of non-methane volatile organic compounds from combustion of domestic fuels in Delhi, India." Atmospheric Chemistry and Physics 21, no. 4 (February 18, 2021): 2383–406. http://dx.doi.org/10.5194/acp-21-2383-2021.
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Abstract. Twenty-nine different fuel types used in residential dwellings in northern India were collected from across Delhi (76 samples in total). Emission factors of a wide range of non-methane volatile organic compounds (NMVOCs) (192 compounds in total) were measured during controlled burning experiments using dual-channel gas chromatography with flame ionisation detection (DC-GC-FID), two-dimensional gas chromatography (GC × GC-FID), proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF-MS) and solid-phase extraction two-dimensional gas chromatography with time-of-flight mass spectrometry (SPE-GC × GC–ToF-MS). On average, 94 % speciation of total measured NMVOC emissions was achieved across all fuel types. The largest contributors to emissions from most fuel types were small non-aromatic oxygenated species, phenolics and furanics. The emission factors (in g kg−1) for total gas-phase NMVOCs were fuelwood (18.7, 4.3–96.7), cow dung cake (62.0, 35.3–83.0), crop residue (37.9, 8.9–73.8), charcoal (5.4, 2.4–7.9), sawdust (72.4, 28.6–115.5), municipal solid waste (87.3, 56.6–119.1) and liquefied petroleum gas (5.7, 1.9–9.8). The emission factors measured in this study allow for better characterisation, evaluation and understanding of the air quality impacts of residential solid-fuel combustion in India.
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Sebos, I., and L. E. Kallinikos. "Modelling of NMVOC emissions from solvents use in Greece." IOP Conference Series: Earth and Environmental Science 1123, no. 1 (December 1, 2022): 012072. http://dx.doi.org/10.1088/1755-1315/1123/1/012072.
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Abstract The use of solvents and other volatile organic chemicals is a significant source of Non-Methane Volatile Organic Compounds (NMVOCs) emissions. Due to the wide spectrum of applications of solvents and numerous locations where these occur, the estimation of NMVOCs emissions can be challenging. The aim of this paper is to present the methodological framework used in Greece for the estimation of NMVOCs emissions. It covers processes and products that use solvents and other volatile organic chemicals in several industries, as well as in households. The framework is based both on existing methods found in the literature and on new emission factors developed in order to reflect the mitigation potential of EU Directives and national legislation aiming at the reduction of NMVOCs emissions. The developed framework was verified by comparing it with solvent emission estimates from the European Solvent Industry Group.
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Sebos, Ioannis, and Leonidas Kallinikos. "NMVOC Emissions from Solvents Use in Greece: Monitoring and Assessment." Atmosphere 14, no. 1 (December 23, 2022): 24. http://dx.doi.org/10.3390/atmos14010024.
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The use of solvents and other volatile organic chemicals is a significant source of Non-Methane Volatile Organic Compounds (NMVOCs) emissions. Due to the wide spectrum of applications of solvents and numerous locations where these occur, the estimation of NMVOCs emissions can be challenging. The aim of this paper is to present the methodological framework used in Greece for the estimation of NMVOCs emissions. It covers processes and products that use solvents and other volatile organic chemicals in several industries, as well as in households. The framework is based both on existing methods found in the literature and on new emission factors developed in order to reflect the mitigation potential of EU Directives and national legislation aiming at the reduction of NMVOCs emissions. The developed framework was used to forecast future NMVOCs emissions and assess the implemented mitigation actions. Results were verified by comparison with solvent emission estimates from the European Solvent Industry Group.
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Mo, Ziwei, Ru Cui, Bin Yuan, Huihua Cai, Brian C. McDonald, Meng Li, Junyu Zheng, and Min Shao. "A mass-balance-based emission inventory of non-methane volatile organic compounds (NMVOCs) for solvent use in China." Atmospheric Chemistry and Physics 21, no. 17 (September 14, 2021): 13655–66. http://dx.doi.org/10.5194/acp-21-13655-2021.
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Abstract. Non-methane volatile organic compounds (NMVOCs) are important precursors of ozone (O3) and secondary organic aerosol (SOA), which play key roles in tropospheric chemistry. A huge amount of NMVOC emissions from solvent use are complicated by a wide spectrum of sources and species. This work presents a long-term NMVOC emission inventory of solvent use during 2000–2017 in China. Based on a mass (material) balance method, NMVOC emissions were estimated for six categories, including coatings, adhesives, inks, pesticides, cleaners, and personal care products. The results show that NMVOC emissions from solvent use in China increased rapidly from 2000 to 2014 then kept stable after 2014. The total emission increased from 1.6 Tg (1.2–2.2 Tg at 95 % confidence interval) in 2000 to 10.6 Tg (7.7–14.9 Tg) in 2017. The substantial growth is driven by the large demand for solvent products in both industrial and residential activities. However, increasing treatment facilities in the solvent-related factories in China restrained the continued growth of solvent NMVOC emissions in recent years. Rapidly developing and heavily industrialized provinces such as Jiangsu, Shandong, and Guangdong contributed significantly to the solvent use emissions. Oxygenated VOCs, alkanes, and aromatics were the main components, accounting for 42 %, 28 %, and 21 % of total NMVOC emissions in 2017, respectively. Our results and previous inventories are generally comparable within the estimation uncertainties (−27 %–52 %). However, there exist significant differences in the estimates of sub-categories. Personal care products were a significant and quickly rising source of NMVOCs, which were probably underestimated in previous inventories. Emissions from solvent use were growing faster compared with transportation and combustion emissions, which were relatively better controlled in China. Environmentally friendly products can reduce the NMVOC emissions from solvent use. Supposing all solvent-based products were substituted with water-based products, it would result in 37 %, 41 %, and 38 % reduction of emissions, ozone formation potential (OFP), and secondary organic aerosol formation potential (SOAP), respectively. These results indicate there is still large potential for NMVOC reduction by reducing the utilization of solvent-based products and implementation of end-of-pipe controls across industrial sectors.
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Pecorini, Isabella, Elena Rossi, and Renato Iannelli. "Mitigation of Methane, NMVOCs and Odor Emissions in Active and Passive Biofiltration Systems at Municipal Solid Waste Landfills." Sustainability 12, no. 8 (April 15, 2020): 3203. http://dx.doi.org/10.3390/su12083203.
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Biofiltration systems are emerging technological solutions for the removal of methane and odors from landfill gas when flaring is no longer feasible. This work analyzed and compared two full-scale biofiltration systems: biofilter and biowindows. The emission mitigation of methane, non-methane volatile organic compounds (NMVOCs) and odors during a two-year management and monitoring period was studied. In addition to diluted methane, more than 50 NMVOCs have been detected in the inlet raw landfill gas and the sulfur compounds resulted in the highest odor activity value. Both systems, biofilter and biowindows, were effective for the oxidation of methane (58.1% and 88.05%, respectively), for the mitigation of NMVOCs (higher than 80%) and odor reduction (99.84% and 93.82% respectively). As for the biofilter monitoring, it was possible to define the oxidation efficiency trend and in fact to guarantee that for an oxidation efficiency of 80%, the methane load must be less than 6.5 g CH4/m2h with an oxidation rate of 5.2 g CH4/m2h.
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An, Jingyu, Yiwei Huang, Cheng Huang, Xin Wang, Rusha Yan, Qian Wang, Hongli Wang, et al. "Emission inventory of air pollutants and chemical speciation for specific anthropogenic sources based on local measurements in the Yangtze River Delta region, China." Atmospheric Chemistry and Physics 21, no. 3 (February 10, 2021): 2003–25. http://dx.doi.org/10.5194/acp-21-2003-2021.
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Abstract. A high-resolution air pollutant emission inventory for the Yangtze River Delta (YRD) region was updated for 2017 using emission factors and chemical speciation based mainly on local measurements in this study. The inventory included 424 non-methane volatile organic compounds (NMVOCs) and 43 fine particulate matter (PM2.5) species from 259 specific sources. The total emissions of SO2, NOx, CO, NMVOCs, PM10, PM2.5, and NH3 in the YRD region in 2017 were 1552, 3235, 38 507, 4875, 3770, 1597, and 2467 Gg, respectively. SO2 and CO emissions were mainly from boilers, accounting for 49 % and 73 % of the total. Mobile sources dominated NOx emissions, contributing 57 % of the total. NMVOC emissions, mainly from industrial sources, made up 61 % of the total. Dust sources accounted for 55 % and 28 % of PM10 and PM2.5 emissions, respectively. Agricultural sources accounted for 91 % of NH3 emissions. Major PM2.5 species were OC, Ca, Si, PSO4, and EC, accounting for 9.0 %, 7.0 %, 6.4 %, 4.6 %, and 4.3 % of total PM2.5 emissions, respectively. The main species of NMVOCs were aromatic hydrocarbons, making up 25.3 % of the total. Oxygenated volatile organic compounds (OVOCs) contributed 21.9 % of the total NMVOC emissions. Toluene had the highest comprehensive contribution to ozone (O3) and secondary organic aerosol (SOA) formation potentials, while other NMVOCs included 1,2,4-trimethylbenzene, m,p-xylene, propylene, ethene, o-xylene, and ethylbenzene. Industrial process and solvent-use sources were the main sources of O3 and SOA formation potential, followed by motor vehicles. Among industrial sources, chemical manufacturing, rubber and plastic manufacturing, appliance manufacturing, and textiles made significant contributions. This emission inventory should provide scientific guidance for future control of air pollutants in the YRD region of China.
Dissertations / Theses on the topic "Non-methane volatile organic compounds (NMVOCs)"
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Marais, Eloise Ann. "Non-methane volatile organic compounds in Africa: a vew from space." Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11313.
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Isoprene emissions affect human health, air quality, and the oxidative capacity of the atmosphere. Globally anthropogenic non-methane volatile organic compounds (NMVOC) emissions are lower than that of isoprene, but local hotspots are hazardous to human health and air quality. In Africa the tropics are a large source of isoprene, while Nigeria appears as a large contributor to regional anthropogenic NMVOC emissions. I make extensive use of space-based formaldehyde (HCHO) observations from the Ozone Monitoring Instrument (OMI) and the chemical transport model (CTM) GEOS-Chem to estimate and examine seasonality of isoprene emissions across Africa, and identify sources and air quality consequences of anthropogenic NMVOC emissions in Nigeria.Earth and Planetary Sciences
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Petrea, Dana Monica Violeta [Verfasser]. "Emissions of non-methane volatile organic compounds (NMVOC) from vehicular traffic in Europe / by Dana Monica Violeta Petrea." 2007. http://d-nb.info/985159413/34.
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Blunden, Jessica. "Characterization of non-methane volatile organic compounds at swine facilities in eastern North Carolina." 2003. http://www.lib.ncsu.edu/theses/available/etd-07282003-105055/unrestricted/etd.pdf.
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Rumsey, Ian Cooper. "Characterizing reduced sulfur compounds and non-methane volatile organic compounds emissions from a swine concentrated animal feeding operation." 2010. http://www.lib.ncsu.edu/theses/available/etd-02042010-235630/unrestricted/etd.pdf.
Full textBooks on the topic "Non-methane volatile organic compounds (NMVOCs)"
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Agency, Ireland Environmental Protection. Estimation of emissions of non methane volatile organic compounds (NMVOCS) from SNAP Sector 06: Solvent & other product use for Ireland in 1998. Johnstown Castle: Environmental Protection Agency, An Gníomhaireacht um Chaomhnú Comhshaoil, 2001.
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Jean, Finn, Cork RTC. Clean Technology Centre., and Ireland Environmental Protection Agency, eds. Estimation of emisions of non methane volatile organic compounds (NMVOCS) from snap sector 06: Solvent & other product use for Ireland in 1998 : final report. Johnstown Castle, Co. Wexford: Environmental Protection Agency, 2001.
Find full textBook chapters on the topic "Non-methane volatile organic compounds (NMVOCs)"
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Gulia, Sunil, Richa Sehgal, Sumit Sharma, and Mukesh Khare. "Emission Inventorisation and Modelling of Non-Methane Volatile Organic Compounds from Petrol Distribution Centres in an Urban Area." In Environmental Pollution, 243–52. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-5792-2_21.
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Lelieveld, Jos. "Air Pollution and Climate." In The Physical Geography of the Mediterranean. Oxford University Press, 2009. http://dx.doi.org/10.1093/oso/9780199268030.003.0038.
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It has long been known that atmospheric pollutants can be hazardous to human health and ecosystems. This includes effects from episodic peak levels as well as the long-term exposure to relatively moderate concentration enhancements. Environmental issues related to air pollution include acidification, mostly by the strong acids from sulphur and nitrogen oxides, eutrophication by the deposition of reactive nitrogen compounds, the reduction of air quality by photo-oxidants and particulate matter, and the radiative forcing of climate by increasing greenhouse gases and by aerosol particles. Many air pollutants are photochemically formed within the atmosphere from emissions by traffic, energy generation, industry, the burning of wastes, and forest fires. The Mediterranean basin in summer is largely cloudfree, and the relatively intense solar radiation promotes the photochemical formation of ozone (O3) and peroxyacetyl nitrate (PAN); O3 being health hazardous at levels in excess of about 100 μg/m3. Ozone is formed in the lower atmosphere as a by-product in the oxidation of reactive carbon compounds such as carbon monoxide (CO) and non-methane volatile organic compounds (NMVOC), catalysed by nitrogen oxides (NOx ≡ NO + NO2). In summer, notably the period from June to August, transport pathways of air pollution near the earth’s surface are typically dominated by northerly winds, carrying photo-oxidants and aerosol particles from Europe into the Mediterranean basin. Aerosol particles with a diameter of less than ∼10 μm (PM10) can have adverse health effects at a concentration of about 30 μg/m3 or higher. The fine mode particles (<2 μm diameter) are mostly composed of sulphates, nitrates, and particulate organic matter, whereas the coarse mode particles (≥2 μm) often contain substantial amounts of sea salt, Saharan dust (Chapter 14), and other mineral components. The aerosols can form widespread hazes that scatter and absorb solar radiation, thus reducing downward energy transfer and surface heating. Increased aerosol scattering causes a negative radiative forcing of climate (cooling tendency), to be weighted against the positive radiative forcing (warming tendency) by increasing greenhouse gases such as carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), halocarbons, and tropospheric ozone (IPCC 2001).
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Sinha, Vinayak, Haseeb Hakkim, and Vinod Kumar. "Advances in Identification and Quantification of Non-methane Volatile Organic Compounds Emitted from Biomass Fires through Laboratory Fire Experiments." In Advances in Atmospheric Chemistry, 169–97. WORLD SCIENTIFIC, 2019. http://dx.doi.org/10.1142/9789813271838_0003.
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Bianchi, Thomas S. "Dissolved Gases in Water." In Biogeochemistry of Estuaries. Oxford University Press, 2006. http://dx.doi.org/10.1093/oso/9780195160826.003.0012.
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Dissolved gases are critically important in many of the biogeochemical cycles of estuaries and coastal waters. However, only recently have there been large-scale collaborative efforts addressing the importance of coupling between estuaries and the atmosphere. For example, the Biogas Transfer in Estuaries (BIOGEST) project, which began in 1996, was focused on determining the distribution of biogases [CO2, CH4, CO, non-methane hydrocarbons, N2O, dimethyl sulfide (DMS), carbonyl sulfide (COS), volatile halogenated organic compounds, and some biogenic volatile metals] in European estuaries and their impact on global budgets (Frankignoulle and Middelburg, 2002). The role of the estuaries and other coastal ocean environments as global sources and/or sinks of key greenhouse gases, like CO2, have also been a subject of intense interest in recent years (Frankignoulle et al., 1996; Cai and Wang, 1998; Raymond et al., 1997, 2000; Cai, 2003; Wang and Cai, 2004). Similarly, O2 transfer across the air–water interface is critical for the survival of most aquatic organisms. Unfortunately, many estuaries around the world are currently undergoing eutrophication, which commonly results in low O2 concentrations (or hypoxic ≤ 2 mg L−1), due to excessive nutrient loading in these systems (Rabalais and Turner, 2001; Rabalais and Nixon, 2002). To understand how gases are transferred across the air–water boundary we will first examine the dominant atmospheric gases and physical parameters that control their transport and solubility in natural waters. The atmosphere is also composed of aerosols, which are defined as condensed phases of solid or liquid particles, suspended in state, that have stability to gravitational separation over a period of observation (Charlson, 2000). Chemical composition and speciation in atmospheric aerosols is important to understanding their behavior after deposition, and is strongly linked with the dominant sources of aerosols (e.g., windblown dust, seasalt, combustion). The importance of aerosol deposition to estuaries and coastal waters, via precipitation (rain and snow) and/or dry particle deposition, has received considerable attention in recent years. For example, dry and wet deposition of nutrients (Paerl et al., 2002; Pollman et al., 2002) and metal contaminants (Siefert et al., 1998; Guentzel et al., 2001) has proven to be significant in biogeochemical budgets in wetlands and estuaries.
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Su, Chunming, Robert W. Puls, Thomas A. Krug, Mark T. Watling, Suzanne K. O'Hara, Jacqueline W. Quinn, and Nancy E. Ruiz. "Long-Term Performance Evaluation of Groundwater Chlorinated Solvents Remediation Using Nanoscale Emulsified Zerovalent Iron at a Superfund Site." In Waste Management, 1352–71. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-1210-4.ch061.
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This chapter addresses a case study of long-term assessment of a field application of environmental nanotechnology. Dense Non-Aqueous Phase Liquid (DNAPL) contaminants such as Tetrachloroethene (PCE) and Trichloroethene (TCE) are a type of recalcitrant compounds commonly found at contaminated sites. Recent research has focused on their remediation using environmental nanotechnology in which nanomaterials such as nanoscale Emulsified Zerovalent Iron (EZVI) are added to the subsurface environment to enhance contaminant degradation. Such nanoremediation approach may be mostly applicable to the source zone where the contaminant mass is the greatest and source removal is a critical step in controlling the further spreading of the groundwater plume. Compared to micro-scale and granular counterparts, NZVI exhibits greater degradation rates due to its greater surface area and reactivity from its faster corrosion. While NZVI shows promise in both laboratory and field tests, limited information is available about the long-term effectiveness of nanoremediation because previous field tests are mostly less than two years. Here an update is provided for a six-year performance evaluation of EZVI for treating PCE and its daughter products at a Superfund site at Parris Island, South Carolina, USA. The field test consisted of two side-by-side treatment plots to remedy a shallow PCE source zone (less than 6 m below ground surface) using pneumatic injection and direct injection, separately in October 2006. For the pneumatic injections, a two-step injection procedure was used. First, the formation was fluidized by the injection of nitrogen gas alone, followed by injection of the EZVI with nitrogen gas as the carrier. In the pneumatic injection plot, 2,180 liters of EZVI containing 225 kg of iron (Toda RNIP-10DS), 856 kg of corn oil, and 22.5 kg of surfactant were injected to remedy an estimated 38 kg of chlorinated volatile compounds (CVOC)s. Direct injections were performed using a direct push rig. In the direct injection plot, 572 liters of EZVI were injected to treat an estimated 0.155 kg of CVOCs. Visual inspection of collected soil cores before and after EZVI injections shows that the travel distance of EZVI was dependent on the method of delivery with pneumatic injection achieving a greater distance of 2.1 m than did direct injection reaching a distance of 0.89 m. Significant decreases in PCE and TCE concentrations were observed in downgradient wells with corresponding increases in degradation products including significant increases in ethene. In the pneumatic injection plot, there were significant reductions in the downgradient groundwater mass flux values for chlorinated ethenes (>58%) and a significant increase in the mass flux of ethene (628%). There were significant reductions in total CVOCs mass (78%), which was less than an estimated 86% decrease in total CVOCs made at 2.5 years due to variations in soil cores collected for CVOCs extraction and determination; an estimated reduction of 23% (vs.63% at 2.5 years) in the sorbed and dissolved phases and 95% (vs. 93% at 2.5 years) reduction in the PCE DNAPL mass. Significant increases in dissolved sulfide, volatile fatty acids (VFA), and total organic carbon (TOC) were observed and dissolved sulfate and pH decreased in many monitoring wells. The apparent effective destruction of CVOC was accomplished by a combination of abiotic dechlorination by nanoiron and biological reductive dechlorination stimulated by the oil in the emulsion. No adverse effects of EZVI were observed for the microbes. In contrast, populations of dehalococcoides showed an increase up to 10,000 fold after EZVI injection. The dechlorination reactions were sustained for the six-year period from a single EZVI delivery. Repeated EZVI injections four to six years apart may be cost-effective to more completely remove the source zone contaminant mass. Overall, the advantages of the EZVI technology include an effective “one-two punch” of rapid abiotic dechlorination followed by a sustained biodegradation; contaminants are destroyed rather than transferred to another medium; ability to treat both DNAPL source zones and dissolved-phase contaminants to contain plume migration; ability to deliver reactants to targeted zones not readily accessible by conventional permeable reactive barriers; and potential for lower overall costs relative to alternative technologies such as groundwater pump-and-treat with high operation and maintenance costs or thermal technologies with high capital costs. The main limitations of the EZVI technology are difficulty in effectively distributing the viscous EZVI to all areas impacted with DNAPL; potential decrease in hydraulic conductivity due to iron corrosion products buildup or biofouling; potential to adversely impact secondary groundwater quality through mobilization of metals and production of sulfides or methane; injection of EZVI may displace DNAPL away from the injection point; and repeated injections may be required to completely destroy the contaminants.
Conference papers on the topic "Non-methane volatile organic compounds (NMVOCs)"
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Kamel, Merhane, and Khalid Al Shehhi. "VOC Recovery System for Crude Oil Tanker Loading." In ADIPEC. SPE, 2022. http://dx.doi.org/10.2118/210906-ms.
Full textAbstract:
Abstract During offshore and onshore loading of crude oil tankers, huge volumes of valuable Volatile Organic Compounds (VOC) are emitted to the atmosphere maybe up to 330 ton per Very Large Crude Oil Carrier (VLCC). When these emissions are liquified, they will be equal to hundreds of barrels of oil. They are a substantial source of financial loss and destructive environmental impact. The objective of this paper is to introduce a Vapor Recovery System concept which can limit & recover the emissions of VOC up to 90% at the Fujairah Terminal. All loading and unloading of oil on offshore, on Floating Storage Offloading Unit (FSOs) and Floating Production Storage Offloading (FPSOs), on onshore storage tanks and terminals, and on shuttle tankers contribute to significant emissions of VOCs. It is possible to install Vapor Recovery Unit (VRU) on each of these applications to capture and recover VOCs. There are two generic approaches to VOC recovery, known as ‘Active’ and ‘Passive’ VOC recovery technology. The Active Vapor Recovery Unit VRU systems typically include a compression step followed by condensation, absorption and/or adsorption. The Passive VRU systems use vapor-balanced loading/unloading with VOC as blanket gas for storage vessels. The VOCs are a combination of Methane and Non-Methane components which evaporate from crude oil and are typically vented into the atmosphere during routine ship loading activities, causing emissions of harmful vapor to the environment. These vapors also represent a fire/explosion hazard. The methodology will be to apply a new concept to limit and recover the VOC emissions during loading of crude oil tankers alongside a Single Point Mooring (SPM). The VOC recovery technology is a unique combination of a modern offshore Supply Vessel (OSV) which considers both hydrocarbon recovery as well as power generation.