Fant 9747 publikasjoner. Viser side 357 av 390:
2021
2015
2004
2004
Analysis of station classification and network design in Europe. ETC/ACM Technical Paper, 2013/18
2013
2016
Analysis of public interest in environmental health information: Fine tuning content for dissemination via social media. Lecture Notes in Computer Science, Vol. 10078
2016
2003
Flue gas recirculation (FGR) is a method used in several industries to control emissions and process conditions, such as NOx reduction and temperature levels, and increase the CO2 concentration in the off-gas, to be better suited for methods of carbon capture. In this study, the influence of FGR, varying levels of flue gas flow and oxygen concentration on the emissions of polycyclic aromatic hydrocarbons (PAHs) was investigated during Si alloy production. In addition, computational fluid dynamics (CFD) modeling was performed using OpenFOAM for combustion of C2H2 and H2 with varying O2 levels to simulate FGR and to gain better insight into the impact of furnace operations on the PAH evolution. Experimental results show that increasing FGR (0–82.5%) and decreasing levels of oxygen (20.7–13.3 vol %) increase the PAH-42 concentration from 14.1 to 559.7 μg/Nm3. This is supported by the simulations, where increased formation of all PAHs species was observed at high levels of FGR, especially for the lighter aromatic species (like benzene and naphthalene), due to the lower availability of oxygen and the reduction in temperature. Residence time was identified as another key parameter to promote complete combustion of PAHs. Benzene oxidation can be prevented with temperatures lower than 1000 K and residence times smaller than 1 s, while complete oxidation is found at temperatures of around 1500 K.
American Chemical Society (ACS)
2023
2005
2005
Analysis of per- and polyfluorinated substances in articles. Nordiske Arbejdspapirer, 2015:911
2015
2007
Silicon alloys are produced by carbothermic reduction of quartz in a submerged arc furnace. This high-temperature pyrolytic process is a source of polycyclic aromatic hydrocarbons (PAHs), which are a group of aromatic organic molecules with known mutagenic and carcinogenic properties. In this study, the emission of oxy- and nitro-PAHs from a pilot-scale Si furnace, with varying process conditions such as oxygen level, flue gas recirculation (FGR), and off-gas flow, was investigated. Analysis shows the presence of both oxy- and nitro-PAH species in all experiments, believed to be formed from radical-induced substitution reactions initiated by SiO combustion and NOx formation. During Si production without FGR, the levels of oxy- and nitro-PAHs range between 1.1 and 4.4 μg Nm−3, independent of the flue gas flow rate. With increasing FGR (0–82.5%) and decreasing oxygen level (20.7–13.3%), the concentrations of both oxy- and nitro-PAHs increase to 36.6 and 65.9 μg Nm−3, respectively. When the levels of substituted PAHs increase, species such as 4-nitropyrene and 1,2-benzanthraquinone are in abundance compared to their parent PAHs. Experiments at lower flue gas flow (500 Nm3 h−1 versus 1000 Nm3 h−1) generally produce less substituted PAHs, as well as SiO2 particulate matter and NOx, where the latter two parameters have a 99% correlation in this study.
Royal Society of Chemistry (RSC)
2023
Analysis of nanoparticle-induced DNA damage by the comet assay. Methods in Pharmacology and Toxicology
2014
This report provides a summary of the quality analysis of the EU Member States’ submission under 18 (1) (b) of the Regulation on the Governance of the Energy Union and Climate Action (EU) 2018/1999 conducted in 2021. Under this obligation EU Member States have to submit updated GHG projections and related information biennially. The reported information undergoes several phases of QA/QC checks consisting of checks on timeliness, accuracy, completeness, consistency and comparability. Details on the underlying QA/QC procedure are described in ETC/CME Eionet Report 7/2021.
ETC/CME
2021
2005
2003
2004