• 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 ...
    • Bubble Evolution on Different Carbon Anode Designs in Cryolite Melt 

      Stanic, Nikolina; Jevremovic, Ivana; Martinez, Ana Maria Cuellar; Sandnes, Espen (Peer reviewed; Journal article, 2020)
      The anode potential has been shown to be highly dependent on anode geometry and orientation in the Hall–Héroult process. This work is an experimental laboratory scale study of the effect of anode geometry and orientation ...
    • CO and CO2 Anode Gas Concentration at Lower Current Densities in Cryolite Melt 

      Stanic, Nikolina; Bø, Embla Knutsdotter Øi Tharaldse; Sandnes, Espen (Peer reviewed; Journal article, 2020)
      This work aims to study the CO-CO2 gas composition at low potentials and low current densities in cryolite melt with relatively low alumina content (≤2 wt%). There is a scarcity of data in the literature regarding the low ...
    • 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 ...
    • 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 ...
    • Interface resolved simulations of continuum scale electrochemical hydrogen evolution 

      Vachaparambil, Kurian J. (Doctoral theses at NTNU;2020:363, Doctoral thesis, 2020)
      An important aspect of improving the efficiency of water electrolysis is to remove the electrochemically generated hydrogen and oxygen bubbles. The evolution of these gases, which are associated with increased electrical ...
    • 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 ...
    • PFC Evolution in the Aluminium Production Process 

      Åsheim, Henrik (Doctoral theses at NTNU;2017:137, Doctoral thesis, 2017)
      Improvements in the Hall-Héroult process for electrowinning of aluminium have drastically reduced the anode effect duration, frequency and its associated perfluorocarbon (PFC) evolution, especially over the past 50 years. ...
    • 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 ...
    • Study of a Graphite Sensor for Alumina Concentration Measurements in Cryolite Melts 

      Nilsen, Karoline Aasen (Master thesis, 2018)
      Alumina dissolution is one of the most crucial processes taking place in the Hall-Héroult process for the production of primary aluminium. One of the key issues for advanced aluminium electrolysis is therefore to understand ...
    • The anode process on carbon in chloride-oxide melts 

      Sandnes, Espen (Doktoravhandlinger ved NTNU, 1503-8181; 2008:120, Doctoral thesis, 2008)
    • 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 ...
    • The Influence of Polarization on the Wetting of Anodes in the Hall-Héroult Process 

      Eidsvaag, Ingrid Andersen (Master thesis, 2016)
      Improvements in the Hall Héroult process for aluminium electrolysis has lead to a reduction in energy consumption from 20-25 kWh/kg Al 70 years ago, down to around 13-14 kWh/kg Al on average today. In order to further ...
    • 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 ...
    • 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 ...