Blar i NTNU Open på forfatter "Tangstad, Merete"

Viser treff 61-80 av 144

    • Investigation of Two Immiscible Liquids Wetting at Elevated Temperature: Interaction Between Liquid FeMn Alloy and Liquid Slag 

      Bao, Sarina; Tangstad, Merete; Tang, Kai; Einarsrud, Kristian Etienne; Syvertsen, Martin; Onsøien, Morten Ingar; Kudyba, Artur; Bublik, Sergey (Peer reviewed; Journal article, 2021)
      The goal of the current work is to develop a methodology to study the wetting behaviour of two immiscible liquids at high temperatures, and to investigate the parameters which influence the wetting properties. The wetting ...

    • Isothermal Reduction of Nchwaning Manganese Ore in CO/CO2/H2 Atmospheres 

      Schanche, Trygve Lindahl; Tangstad, Merete (Journal article, 2021)
      In the industrial production of manganese ferroalloys, incomplete pre-reduction of higher manganese- and iron oxides in the furnace causes an excess consumption of carbon and energy. Pre-treatment of the manganese raw ...

    • Karbiddannelse i Manganovner 

      Øvrelid, Sigurd Johannes Slåtsve (Master thesis, 2019)
      Når karbon løses opp i silikomangan(SiMn)-prosessen kan det dannes titankarbid (TiC), silisiumkarbid (SiC) eller grafitt i ovnen. Silisiuminnholdet i legeringen avgjør om silisiumkarbid eller grafitt vil være den stabile ...

    • Kinetic Investigations of SiMn Slags From Different Mn Sources 

      Kim, Pyunghwa; Tangstad, Merete (Journal article; Peer reviewed, 2018)
      The kinetics of MnO and SiO2 reduction were investigated for Silicomanganese (SiMn) slags using a Thermogravimetric analysis (TGA) between 1773 K and 1923 K (1500 °C and 1650 °C) under CO atmospheric pressure. The charge ...

    • Kinetic modeling of the reaction rate for quartz and carbon pellet 

      Li, Fei; Tangstad, Merete (Journal article; Peer reviewed, 2018)
      Kinetic modeling of quartz and carbon pellet at temperatures of 1898 K, 1923 K, and 1948 K (1625 °C, 1650 °C, and 1675 °C) was investigated in this study. The carbon materials used were charcoal, coke, coal, and preheated ...

    • Kinetics of Slag Reduction in Silicomanganese Production 

      Canaguier, Vincent Yves; Tangstad, Merete (Peer reviewed; Journal article, 2020)
      In this study, the reduction of three silicomanganese charges prepared from industrial raw materials was investigated under isothermal conditions between 1783 K and 1933 K (1510 °C and 1660 °C). The main reactions examined ...

    • Kinetics of the reaction between quartz and silicon carbide in different gas atmospheres 

      Ni, Feng (Master thesis, 2015)
      This thesis examined the influence of different gas species in the kinetics of SiO2+SiC reaction. The quartz and silicon carbide were crushed to < 38µm, uniformly mixed together with weight ratio of 3:1 and pelletized into ...

    • Life cycle assessment of renewable reductants in the ferromanganese alloy production: A review 

      Surup, Gerrit Ralf; Trubetskaya, Anna; Tangstad, Merete (Peer reviewed; Journal article, 2021)
      This study examined the literature on life cycle assessment on the ferromanganese alloy production route. The environmental impacts of raw material acquisition through the production of carbon reductants to the production ...

    • Life Cycle Assessment of Renewable Reductants in the Ferromanganese Alloy Production: A Review 

      Surup, Gerrit Ralf; Trubetskaya, Anna; Tangstad, Merete (Peer reviewed; Journal article, 2021)
      This study examined the literature on life cycle assessment on the ferromanganese alloy production route. The environmental impacts of raw material acquisition through the production of carbon reductants to the production ...

    • Life Cycle Based Climate Emissions of Charcoal Conditioning Routes for the Use in the Ferro-Alloy Production 

      Surup, Gerrit Ralf; Kaffash, Hamideh; Ma, Yan; Trubetskaya, Anna; Pettersen, Johan Berg; Tangstad, Merete (Peer reviewed; Journal article, 2022)
      Renewable reductants are intended to significantly reduce CO2 emissions from ferro-alloy production, e.g., by up to 80% in 2050 in Norway. However, charcoals provide inferior properties compared to fossil fuel-based ...

    • Metal loss comprehension - metal emulsions in ferromanganese slags 

      Datin, Paul Guillaume Jean Clair (Master thesis, 2015)
      Literature review was done on metal in slag emulsions, using the surface phenomena literature in metallurgy as well as the oil and water emulsion broader literature. Several phenomena were found that could extend to the ...

    • Metal-producing Mechanisms in the Carbothermic Silicon Process 

      Vangskåsen, Jørund (Master thesis, 2012)
      The mechanisms in the carbothermic production of silicon have been examined in this report. Through the investigation of a pilot scale furnace as well as five small scale induction furnace experiments, a better understanding ...

    • Methods for K-impregnation of carbon materials and their effect on the CO2 reactivity 

      Solhaug, Emma (Master thesis, 2022)
      En veldig stor andel av det norske CO2utslippet kommer som en følge av bruk av fossile karbon materialer i metall produksjon. I den norske mangan (Mn) produksjonen er koks mest brukt til å redusere manganmalmen. Denne ...

    • Mn alloys production with the use of natural gas. - Understanding the kinetics of Mn alloy production 

      Nadir, Bilal (Master thesis, 2015)
      This research intends to develop the necessary understanding regarding the reaction kinetics involved in the production of manganese ferroalloys. The main reactions of interest are as follows: MnO_((l) )+C_((s,l))=Mn_((l ...

    • Modelling Gas Flow in Furnaces for Si Production 

      Nordhus, Astrid (Master thesis, 2022)
      Lavere energiforbruk og høyere silisium utbytte er viktig for silisium produksjonen. For å oppnå dette er det viktig med stabile ovnsprosesser. Motstand mot gass-strømning i råmaterialet fører til et økt trykk i ovnen. Om ...

    • Ore melting and reduction in silicomanganese production 

      Ringdalen, Eli; Gaal, S.; Tangstad, Merete; Ostrovski, Oleg (Journal article; Peer reviewed, 2010)
      The charge for silicomangansese production consists of manganese ore (often mixed with ferromanganese slag) dolomite or calcite, quartz, and in some cases, other additions. These materials have different melting properties, ...

    • An Overview of Currently Applied Ferrochrome Production Processes and Their Waste Management Practices 

      du Preez, Stephanus P.; van Kaam, Tristan P. M.; Ringdalen, Eli; Tangstad, Merete; Morita, Kazuki; Bessarabov, Dmitri G.; van Zyl, Pieter G.; Beukes, Johan P. (Peer reviewed; Journal article, 2023)
      Ferrochrome (FeCr) is the main source of virgin chromium (Cr) units used in modern-day chromium (Cr) containing alloys. The vast majority of produced Cr is used during the production of stainless steel, which owes its ...

    • Passivation Threshold for the Oxidation of Liquid Silicon and Thermodynamic Non-equilibrium in the Gas Phase 

      Vadon, Mathieu; Sortland, Øyvind Sunde; 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). A progressive ...

    • Phase Distribution During Slag Formation in Mn Ferroalloy Production 

      Mukono, Tichaona; Wallin, Maria; Tangstad, Merete (Peer reviewed; Journal article, 2022)
      Phase development during slag formation and reduction of Comilog and Assmang ores in a setup that simulates the conditions in an industrial SAF process under different coke bed temperatures, 1473 K (1200 °C), 1673 K (1400 ...

    • Phase Relations in Ferromanganese Production During Prereduction: South African Ores 

      Kalenga, M; Tangstad, Merete; Pan, X (Peer reviewed; Journal article, 2019)
      In the steel industry, ferromanganese is an important additive. During the production of ferromanganese the ore goes through prereduction and reduction. The prereduction step is very important, as the degree of reduction ...