• A multiscale numerical approach of the dripping slag in the coke bed zone of a pilot scale Si-Mn furnace 

      Letout, Sebastien Romain; Ratvik, Arne Petter; Tangstad, Merete; Johansen, Stein Tore; Olsen, Jan Erik (Chapter, 2017)
      The Si-Mn alloy process production in submerged arc furnaces (SAF) is investigated. The aim of the studies currently in progress is an enhancement of the knowledge about the key reactions and the mass transport phenomenon ...
    • AMADEUS: Next generation materials and solid state devices for ultra high temperature energy storage and conversion 

      Datas, Alejandro; Cristobal, Ana Belen; del Cañizo, Carlos; Antolin, Elisa; Beaughon, Michel; Nikolopoulos, Nikolaos; Nikolopoulos, Aristeidis; Zeneli, Myrto; Sobczak, Natalia; Polkowski, Wojciech; Tangstad, Merete; Safarian, Jafar; Trucchi, Daniele M; Bellucci, Alessandro; Girolami, Marco; Marx, Roman; Bestenlehner, Dominik; Lang, Stephan; Vitulano, Aniello; Sabbatella, Gianfranco; Marti, Antonio (Journal article; Peer reviewed, 2018)
      Starting in January 2017, AMADEUS (www.amadeus-project.eu) is the first project funded by the European Commission to research on a new generation of materials and solid state devices for ultra-high temperature energy storage ...
    • As-tapped Liquid Silicon Temperature Measurements in an Industrial Furnace 

      Werner, Tobias (Master thesis, 2019)
      Denne oppgaven tar for seg temperaturmålinger av smeltet silisium i rennen fra en industriell ovn. For at silisiumindustrien skal kunne oppfylle egne og myndigheters mål om forbedret energieffektivitet og lavere ...
    • Boron Removal from Silicon Melts by H2O/H2 Gas Blowing: Mass Transfer in Gas and Melt 

      Sortland, Øyvind Sunde; Tangstad, Merete (Journal article; Peer reviewed, 2014)
      Metallurgical routes for solar grade silicon production are being developed as alternatives to chemical processes for their potential to achieve cost reductions, increased production volume, and reduced environmental and ...
    • CFD Modeling of boron removal from liquid silicon with cold gases and plasma 

      Vadon, Mathieu; Sortland, Øyvind Sunde; Nuta, Ioana; Chatillon, Christian; Tangstad, Merete; Chichignoud, Guy; Delannoy, Yves (Journal article; Peer reviewed, 2018)
      The present study focuses on a specific step of the metallurgical path of purification to provide solar-grade silicon: the removal of boron through the injection of H2O(g)-H2(g)-Ar(g) (cold gas process) or of Ar-H2-O2 ...
    • Characterization of a Si-SiO2 mixture generated from SiO and CO 

      Broggi, Andrea; Tangstad, Merete; Ringdalen, Eli (Journal article; Peer reviewed, 2019)
      The reaction between SiO(g) and CO(g) is a relevant intermediate reaction in the silicon production process. One of the products generated from this gas mixture is called by its color, brown condensate. In this paper, ...
    • Compatibility Study of Carbon-Based Refractory Materials utilized in Silicomanganese Production Furnaces 

      Mølnås, Håvard (Master thesis, 2011)
      Tap hole refractories constitute critical parts of the refractory lining in submerged arc furnaces. For several hours every day, molten slag and metal flow through the tap hole calling for thorough selection of refractory ...
    • Damring formation during rotary kiln chromite pre-reduction: Effects of pulverized carbonaceous fuel selection and partial pellet melting 

      van Staden, Yolindi; Beukes, Johan Paul; van Zyl, Pieter Gideon; Ringdalen, Eli; Tangstad, Merete; Kleynhans, Ernst L.J.; Bunt, John Reginald (Journal article; Peer reviewed, 2018)
      Electricity consumption is the largest cost contributing factor in the production of ferrochrome. Currently the pelletized chromite pre-reduction process (solid-state reduction of chromite) is the process option with the ...
    • Dissolution kinetics of carbon materials in FeMn 

      Kaffash, Hamideh (Doctoral theses at NTNU;2019:226, Doctoral thesis, 2019)
      Submerged electric arc furnace (SAF) is the main process for industrial production of ferroalloys, in which metal oxides are reduced by carbon. To decrease the production cost and reduce the CO2 emissions, a variety of ...
    • Dynamic Current and Power Distributions in a Submerged Arc Furnace 

      Tesfahunegn, Yonatan; Magnusson, Thordur; Tangstad, Merete; Saevarsdottir, Gudrun (Journal article; Peer reviewed, 2019)
      Most submerged arc furnaces used for the production of ferroalloys run on three-phase alternating current. This affects the electrical operation of the furnace and thus it is of interest to study alternating current ...
    • Dynamic Current Distribution in the Electrodes of Submerged Arc Furnace Using Scalar and Vector Potentials 

      Tesfahunegn, Yonatan; Magnusson, Thordur; Tangstad, Merete; Saevarsdottir, Gudrun (Journal article; Peer reviewed, 2018)
      This work presents computations of electric current distributions inside an industrial submerged arc furnace. A 3D model has been developed in ANSYS Fluent that solves Maxwell’s equations based on scalar and vector potentials ...
    • Effect of Charge Basicity of Two Compositions on MnO Reduction During Smelting Ferromanganese 

      Mwana Bute Ngoy, D; Kalenga wa Kalenga, M; Tangstad, Merete (Journal article; Peer reviewed, 2018)
      The effect of basicity of two different basic charges for reduction of MnO by solid carbon during smelting ferromanganese is considered. The effect of different charge compositions on MnO reduction in the temperature range ...
    • Electrical Resistivity of Carbonaceous Bed Material at High Temperature 

      Surup, Gerrit Ralf; Pedersen, Tommy Andre; Chaldien, Annah; Beukes, Johan Paul; Tangstad, Merete (Peer reviewed; Journal article, 2020)
      This study reports the effect of high-temperature treatment on the electrical properties of charcoal, coal, and coke. The electrical resistivity of industrial charcoal samples used as a reducing agent in electric arc ...
    • Electrode paste behaviour in Søderberg electrodes in ferroalloys production 

      Skjeldestad, Aslak (Doctoral thesis, 2019)
      The main goal of this work has been to study the melting behavior of electrode paste used in Søderberg electrodes in ferroalloy production. It has been done by first measuring temperatures in an industrial electrode and ...
    • Elektrisk resistivitet i industrielle SiC-lag 

      Krokstad, Magnus Austheim (Master thesis, 2014)
      Det antas at 1% av strømmen som går gjennom en ovn som produserer silisiumslegeringer vil gå gjennom chargen mellom elektrodene, resten vil gå gjennom lysbuen som går fra elektroden og til metallbadet. Det er ukjent hvor ...
    • Energy Distribution in HC FeMn and SiMn - Energy vs Exergy Analyses 

      Larssen, Trine Asklund; Kero, Ida; Tangstad, Merete (Peer reviewed; Journal article, 2019)
      The metal producing industry is a high consumer of energy and large amounts of excess heat are produced. Increasing the energy efficiency would be beneficial, both in terms of the environment and also from an economical ...
    • Formation and characterization of β-and α-Silicon Carbide produced during Silicon/Ferrosilicon process 

      Jayakumari, Sethulakshmy (Doctoral theses at NTNU;2020:252, Doctoral thesis, 2020)
      Silicon carbide (SiC) is one of the main intermediate compounds generated during primary silicon (Si) production in submerged arc furnaces. Carbon materials, either biomass-based (charcoal and wood chips) or based on fossil ...
    • Formation of Silicon Carbide and Graphite in the Silicomanganese Process 

      Einan, Jonas (Master thesis, 2012)
      When a liquid SiMn alloy is cooled, carbon is dissolved from the melt. The dissolved carbon either forms graphite or reacts with silicon from the melt to form SiC. The goal of this thesis has been to determine how temperature ...
    • Formation of Silicon Carbide in the Silicomanganese Process 

      Davidsen, Jens Erik (Master thesis, 2011)
      As the silicon content in a silicomanganese alloy increase, silicon carbide becomes the stable carbon phase. Little work is published on the formation of silicon carbide in the SiMn process. This thesis examines the formation ...
    • Gaseous reduction of Mn ores in CO-CO2 atmosphere 

      Larssen, Trine Asklund; Tangstad, Merete; Kero, Ida (Chapter, 2018)
      The efficiency in production of manganese ferroalloys is dependent on the gaseous reduction of the higher manganese oxides in the ores used as raw materials. The materials, descending in the furnace, will meet the furnace ...