Title: | Influence of Atmosphere and Temperature on Polycyclic Aromatic Hydrocarbon Emissions from Green Anode Paste Baking |
Author(s): | Arnesen K; Aarhaug TA; Einarsrud KE; Tranell GM; |
Address: | "Department of Materials Science and Engineering, Norwegian University of Science and Technology (NTNU), 7034 Trondheim, Norway. SINTEF Industry, 7034 Trondheim, Norway" |
ISSN/ISBN: | 2470-1343 (Electronic) 2470-1343 (Linking) |
Abstract: | "Coal tar pitch, a well-known source of polycyclic aromatic hydrocarbons (PAHs), is used as a binder of petroleum coke in prebaked anodes used for electrolysis of aluminum. Anodes are baked up to 1100 degrees C over a 20-day period, where flue gas containing PAHs and volatile organic compounds (VOCs) are treated using techniques such as regenerative thermal oxidation, quenching, and washing. Conditions during baking facilitate incomplete combustion of PAHs, and due to the various structures and properties of PAHs, the effect of temperature up to 750 degrees C and various atmospheres during pyrolysis and combustion were tested. PAH emissions from green anode paste (GAP) dominate in the temperature interval of 251-500 degrees C, where PAH species of 4-6 rings make up the majority of the emission profile. During pyrolysis in argon atmosphere, a total of 1645 mug EPA-16 PAHs are emitted per gram of GAP. Adding 5 and 10% CO(2) to the inert atmosphere does not seem to affect the PAH emission level significantly, at 1547 and 1666 mug/g, respectively. When adding oxygen, concentrations decreased to 569 mug/g and 417 mug/g for 5% and 10% O(2), respectively, corresponding to a 65% and 75% decrease in emission" |
Notes: | "PubMed-not-MEDLINEArnesen, Kamilla Aarhaug, Thor Anders Einarsrud, Kristian Etienne Tranell, Gabriella M eng 2023/05/30 ACS Omega. 2023 May 10; 8(20):18116-18121. doi: 10.1021/acsomega.3c01411. eCollection 2023 May 23" |