Abstract
Current Tier 2 algorithms calculate CF4 emission factors based on average anode effect minutes or average millivolts Overvoltage per cell day. Both the “slope” and “overvoltage” algorithms are based on the assumption that CF4 emission rates remain constant for anode effect durations ranging from less than one second to more than 1000 s. Detailed analysis of PFC measurements made over the past decade has shown conclusively that CF4 emission rates decrease rapidly with increasing reported anode effect duration. Average duration or average overvoltage can be skewed by changes in the mix of anode effect durations, particularly the mix of anode effects mitigated by automatic process control and those much longer anode effects requiring manual intervention. This study analyzes measurement data from individual anode effects from more than 2000 individual anode effects from more than 30 different measurements to develop a new exponential algorithm that better reflects changes in emission rate with anode effect duration. The exponential calculation should prove to be more robust resulting in more accurate calculation of PFC emissions than previous models.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
B P Leber, A T Tabereaux, J Marks, B Lamb, T Howard, R Kantmaneni, M Gibbs, V Bakshi and E J Dolin. “PFC Generation at primary Aluminium Smelters.” Light Metals 1998:277–286.
Intergovernmental Panel on Climate Change, “2006 IPCC Guidelines for National Greenhouse Gas Inventories, Volume 3 Industrial Processes and Product Use, Chapter 4, Metal Industry Emissions,” available at http://www.ipcc-nggip.iges.or.jp/public/2006gl/vol3.html, April 2010.
Li, W., Zhao, Q., Yang, J., Qiu, S., Chen, X., Marks, J. and Bayliss, C., “On Continuous PFC Emission Unrelated to Anode Effects, in Light Metals,” Light Metals 2011:307–314.
L Dion, László I. Kiss, Sándor Poncsák, Charles-Luc Lagacé, “Prediction of Low-Voltage Tetrafluoromethane Emissions Based on the Operating Conditions of an Aluminium Electrolysis Cell,” JOM 68 (9):2472–2482.
David Wong and Jerry Marks, “CONTINUOUS PFC EMISSIONS MEASURED ON INDIVIDUAL 400KA CELLS,” Light Metals 2013:865–870.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2018 The Minerals, Metals & Materials Society
About this paper
Cite this paper
Marks, J., Nunez, P. (2018). New Algorithm for Calculating CF4 Emissions from High Voltage Anode Effects. In: Martin, O. (eds) Light Metals 2018. TMS 2018. The Minerals, Metals & Materials Series. Springer, Cham. https://doi.org/10.1007/978-3-319-72284-9_193
Download citation
DOI: https://doi.org/10.1007/978-3-319-72284-9_193
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-72283-2
Online ISBN: 978-3-319-72284-9
eBook Packages: Chemistry and Materials ScienceChemistry and Material Science (R0)