• A method for comparing the HF formation potential of aluminas with different water contents 

      Sommerseth, Camilla; Osen, Karen Sende; Rosenkilde, Christian; Meyer, Astrid J.; Kristiansen, Linda; Aarhaug, Thor Anders (Chapter, 2012)
      In the aluminium industry today, smelters often have to rely on more than one alumina supplier. This creates diversity in the properties of smelter grade alumina (SGA). A method has been developed to compare the HF formation ...
    • An EXAFS and XANES Study of V, Ni, and Fe Speciation in Cokes for Anodes Used in Aluminum Production 

      Jahrsengene, Gøril; Wells, Hannah C.; Sommerseth, Camilla; Ratvik, Arne Petter; Lossius, Lorentz Petter; Sizeland, Katie H.; Kappen, Peter; Svensson, Ann Mari; Haverkamp, Richard G. (Journal article; Peer reviewed, 2019)
      Lower-quality petroleum coke with higher levels of sulfur and metal impurities will have to be used for the manufacturing of anodes for aluminum production in the future. The sulfur and metallic impurities affect the anode ...
    • Bubble evolution and anode surface properties in aluminium electrolysis 

      Thorne, Rebecca Jayne; Sommerseth, Camilla; Ratvik, Arne Petter; Rørvik, Stein; Sandnes, Espen; Lossius, Lorentz Petter; Linga, Hogne; Svensson, Ann Mari (Journal article, 2015)
      One significant contribution to the anodic potential during aluminum electrolysis is the formation of CO2 bubbles that screen the anode surface. This effect creates an additional ohmic resistance as well as an increased ...
    • Comparing Anodic Bubble Behavior of Anodes from Anisotropic and Isotropic Cokes in Laboratory Scale Aluminum Electrolysis Cells 

      Sommerseth, Camilla; Thorne, Rebecca Jayne; Ratvik, Arne Petter; Rørvik, Stein; Linga, Hogne; Lossius, Lorentz Petter; Svensson, Ann Mari (Journal article; Peer reviewed, 2019)
      During production of aluminum in Hall-Héroult cells, carbon anodes electrochemically oxidize to form mainly CO2. The CO2 bubbles block the anode working surface during growth and coalescence, leading to cell voltage loss ...
    • Correlation between coke type, microstructure and anodic reaction overpotential in aluminium electrolysis 

      Thorne, Rebecca Jayne; Sommerseth, Camilla; Ratvik, Arne Petter; Rørvik, Stein; Sandnes, Espen; Lossius, Lorentz Petter; Linga, Hogne; Svensson, Ann Mari (Journal article; Peer reviewed, 2015)
      Although the anode process during aluminum electrolysis has a substantial overpotential that increases the energy demand and production cost of aluminum, properties of the coke that can influence the electrochemical ...
    • Direct Method for Producing Scandium Metal and Scandium-Aluminium Intermetallic Compounds from the Oxides 

      Martinez, Ana Maria Cuellar; Osen, Karen Sende; Gudbrandsen, Henrik; Sommerseth, Camilla; Wang, Zhaohui; Darell, Ove (Journal article; Peer reviewed, 2018)
      The electrochemical de-oxidation process, also called FFC-Cambridge process, has been proposed previously to produce reactive metals and their alloys through reduction of their metal oxides. The process works by introducing ...
    • Electrochemical Behaviour of Carbon Anodes Produced with Different Mixing Temperatures and Baking Levels—A Laboratory Study 

      Sommerseth, Camilla; Thorne, Rebecca Jayne; Gebarowski, Wojciech; Ratvik, Arne Petter; Rørvik, Stein; Linga, Hogne; Lossius, Lorentz Petter; Svensson, Ann Mari (Chapter, 2019)
      Anodes fabricated from a single source coke were used for investigations of effect of porosity and surface roughness on the electrochemical performance in laboratory scale cells. In order to fabricate anodes differing in ...
    • Electrochemical Reactivity and Wetting Properties of Anodes Made from Anisotropic and Isotropic Cokes 

      Sommerseth, Camilla; Thorne, Rebecca Jayne; Ratvik, Arne Petter; Sandnes, Espen; Rørvik, Stein; Lossius, Lorentz Petter; Linga, Hogne; Svensson, Ann Mari (Journal article, 2016)
      High quality anodes require stable raw materials. As the quality of the coke available for production of anodes is changing, future production will rely on cokes that are more isotropic with higher impurity levels than ...
    • HF Formation Upon Addition of Different Industrial Aluminas to Cryolitic Baths 

      Sommerseth, Camilla (Master thesis, 2011)
      The aluminium smelter at Hydro Sunndal has experienced problems with an unexpected increased loss of AlF3 from the electrolyte when using a certain quality of alumina. One hypothesis considered was that the fluoride loss ...
    • Interfacial Boundary between Carbon Anodes and Molten Salt Electrolyte 

      Gebarowski, Wojciech; Sommerseth, Camilla; Ratvik, Arne Petter; Sandnes, Espen; Lossius, Lorentz Petter; Linga, Hogne; Svensson, Ann Mari (Journal article, 2016)
      The properties of calcined petroleum cokes (CPC), used in the anodes in the Hall-Héroult process, are important for the electrochemical behaviour of the anodes. CPCs from different sources vary not only in impurity level ...
    • Perfluorocarbon Formation During Rare Earth Electrolysis 

      Osen, Karen Sende; Martinez, Ana Maria Cuellar; Gudbrandsen, Henrik; Støre, Anne; Sommerseth, Camilla; Kjos, Ole Sigmund; Aarhaug, Thor Anders; Gaertner, Heiko; Chamelot, Pierre; Gibilaro, Mathieu; Massot, Laurent (Journal article; Peer reviewed, 2018)
      A challenge during rare earth (RE) electrolysis is to avoid emissions of perfluorocarbon (PFC) green-house gases. The objective of this work was to study how to operate the RE electrolysis process with neither PFC formation ...
    • PFC evolution characteristics during aluminium and rare earth electrolysis 

      Kjos, Ole Sigmund; Solheim, Asbjørn; Aarhaug, Thor Anders; Osen, Karen Sende; Martinez, Ana Maria Cuellar; Sommerseth, Camilla; Gudbrandsen, Henrik; Støre, Anne; Gaertner, Heiko (Journal article; Peer reviewed, 2018)
      In addition to aluminium electrolysis, the electrolysis of rare earth (RE) metals from fluoride melts is a significant source of perfluorocarbon (PFC) emissions to the atmosphere. These processes have many similarities, ...
    • Spatial methods for characterising carbon anodes for aluminium production 

      Sommerseth, Camilla; Thorne, Rebecca Jayne; Rørvik, Stein; Sandnes, Espen; Ratvik, Arne Petter; Lossius, Lorentz Petter; Linga, Hogne; Svensson, Ann Mari (Journal article, 2015)
      Pilot test anodes were designed by Hydro Aluminium for laboratory studies using controlled blends of <2 mm aggregate from two single source cokes. Spa- tial and imaging methods were used to characterise anode surfaces with ...
    • The Effect of Production Parameters on the Performance of Carbon Anodes for Aluminium Production 

      Sommerseth, Camilla (Doctoral thesis at NTNU;2016:108, Doctoral thesis, 2016)
      Carbon anodes are essential when producing aluminium. Oxygen from dissolved aluminium oxide reacts electrochemically on the carbon anode forming CO2. The carbon anode is consumed during the process. The production of ...
    • The Effect of Varying Mixing Temperatures and Baking Level on the Quality of Pilot Scale Anodes - A Factorial Design Analysis 

      Sommerseth, Camilla; Thorne, Rebecca Jayne; Ratvik, Arne Petter; Sandnes, Espen; Linga, Hogne; Lossius, Lorentz Petter; Svensson, Ann Mari (Journal article; Peer reviewed, 2017)
      Identifying optimum anode baking level and mixing temperature are important when producing high quality anodes. The effect of varying mixing temperature and baking level were investigated in terms of the resulting apparent ...
    • Understanding Anode Overpotential 

      Thorne, Rebecca Jayne; Sommerseth, Camilla; Svensson, Ann Mari; Sandnes, Espen; Lossius, Lorentz Petter; Linga, Hogne; Ratvik, Arne Petter (Journal article, 2014)
      In aluminium electrolysis cells the anodic process is associated with a substantial overpotential. Industrial carbon anodes are produced from a blend of coke materials, but the effect of coke type on anodic overpotential ...
    • Vanadium Speciation in Petroleum Cokes for Anodes used in Aluminium Electrolysis 

      Jahrsengene, Gøril; Wells, Hannah C.; Sommerseth, Camilla; Ratvik, Arne Petter; Lossius, Lorentz Petter; Haverkamp, Richard G.; Svensson, Ann Mari (Journal article, 2017)
      The expanding aluminium industry is facing challenges with availability in raw materials. A wider range of petroleum cokes are being taken into use, blurring the border between anode grade and fuel grade coke in anode ...
    • Wetting testing of wettable cathodes for aluminium production 

      Haslund, Vilde Stubberud (Master thesis, 2017)
      The aim of this work has been to assess the wettability of a set of carbon-TiB2 composites towards aluminium. In order to do so, further improvements to the immersion-emersion method, a method used to assess the wetting ...