Browsing NTNU Open by Author "Einarsrud, Kristian Etienne"
Now showing items 21-40 of 77
-
Electrical Resistivity of Materials in the Silicon Furnace
Hoover, Haley (Doctoral thesis, 2023)Silicon is becoming an increasingly important part of the modern world through its applications in electronics, solar cells, and silicones, to name a few. Norway is a significant producer of silicon, competing with much ... -
Electrodialytic Energy Storage System: Permselectivity, Stack Measurements and Life-Cycle Analysis
Krakhella, Kjersti Wergeland; Morales, Marjorie; Bock, Robert; Seland, Frode; Burheim, Odne Stokke; Einarsrud, Kristian Etienne (Peer reviewed; Journal article, 2020)Reverse electrodialysis and electrodialysis can be combined into a closed energy storage system, allowing for storing surplus energy through a salinity difference between two solutions. A closed system benefits from simple ... -
Electrolysis in reduced gravitational environments: current research perspectives and future applications
Akay, Ömer; Bashkatov, Aleksandr; Coy, Emerson; Eckert, Kerstin; Einarsrud, Kristian Etienne; Friedrich, Andreas; Kimmel, Benjamin; Loos, Stefan; Mutschke, Gerd; Röntzsch, Lars; Symes, Mark D.; Yang, Xuegeng; Brinkert, Katharina (Peer reviewed; Journal article, 2022)Electrochemical energy conversion technologies play a crucial role in space missions, for example, in the Environmental Control and Life Support System (ECLSS) on the International Space Station (ISS). They are also vitally ... -
Energy generation and storage by salinity gradient power: A model-based assessment
Jalili, Zohreh; Krakhella, Kjersti Wergeland; Einarsrud, Kristian Etienne; Burheim, Odne Stokke (Journal article; Peer reviewed, 2019)Three energy storage systems based on mixing and desalination of solutions with different salt concentrations are presented, namely, reverse electrodialysis, pressure retarded osmosis and capacitive Donnan potential, coupled ... -
Experimental and Numerical Study on Tapping of Two Liquids through a Single Tap-Hole
Loomba, Varun; Olsen, Jan Erik Øvrebø; Reynolds, Quinn Gareth; Oxtoby, Oliver; Einarsrud, Kristian Etienne (Journal article; Peer reviewed, 2023)The production of industrial metals in pyrometallurgical smelting furnaces is central to modern industry. Tapping of metal and slag from smelting furnaces is a complex and difficult process. Any variations from tap to tap ... -
Explanation of Bubble Nucleation Mechanisms: A Gradient Theory Approach
Vachaparambil, Kurian J.; Einarsrud, Kristian Etienne (Journal article; Peer reviewed, 2018)A Helmholtz free energy description of the four nucleation mechanisms used to explain the bubble nucleation in electrochemical systems is presented. The mechanisms are compared based on the nucleation energy barrier and ... -
Feeding of Alumina in Molten Cryolite Bath
Gylver, Sindre Engzelius (Doctoral theses at NTNU;2023:21, Doctoral thesis, 2023)Alumina is the principal raw-material used for the production of aluminum in the Hall- Héroult process and is fed to the electrolytic bath in batches regularly. Maintaining a stable concentration in the bath is important ... -
Flue Gas Recirculation for the Silicon Process
Andersen, Vegar (Doctoral theses at NTNU;2023:135, Doctoral thesis, 2023)Metallurgical-grade silicon is a critical material for modern society. It is used as an alloying agent in aluminium alloys, feedstock for silicones, photovoltaics and electronics. Silicon is produced by carbothermal reduction ... -
The Formation and Disintegration of Rafts from Different Aluminas and Fines
Gylver, Sindre Engzelius; Bekkevoll, Simen; Rørvik, Stein; Einarsrud, Kristian Etienne (Peer reviewed; Journal article, 2022)Raft formation is a frequently encountered problem during alumina feeding in the Hall-Héroult-process and will delay alumina from being dissolved into the melt. The mechanisms for the formation and disintegration of rafts ... -
Gas Flow and Pressure Drop in Charge Material in Silicon Production
Ringdalen, Eli; Einarsrud, Kristian Etienne; Nordhus, Astrid (Peer reviewed; Journal article, 2022)Gassing, outbursts of high-rate gas flows through the taphole, is a phenomenon that sometimes occurs during tapping of silicon furnaces. In addition to being an HSE challenge, this might also affect the tapping, while the ... -
Heat to H2: Using Waste Heat for Hydrogen Production through Reverse Electrodialysis
Krakhella, Kjersti Wergeland; Einarsrud, Kristian Etienne; Burheim, Odne Stokke; Seland, Frode; Bock, Robert (Journal article; Peer reviewed, 2019)This work presents an integrated hydrogen production system using reverse electrodialysis (RED) and waste heat, termed Heat to H2. The driving potential in RED is a concentration difference over alternating anion and cation ... -
Heating New Anodes Using the Waste Heat of Anode Butts: Establishing the Interface Thermal Contact Resistance
Dupuis, Marc; Gudbrandsen, Henrik; Einarsrud, Kristian Etienne (Peer reviewed; Journal article, 2021)In order to be able to assess the rate of heat transfer between a new anode and an anode butt, it is critical to measure the interface thermal contact resistance between them. For that purpose, a lab experiment has been ... -
Influence of Atmosphere and Temperature on Polycyclic Aromatic Hydrocarbon Emissions from Green Anode Paste Baking
Arnesen, Kamilla; Aarhaug, Thor Anders; Einarsrud, Kristian Etienne; Tranell, Maria Gabriella (Peer reviewed; Journal article, 2023)Coal tar pitch, a well-known source of polycyclic aromatic hydrocarbons (PAHs), is used as a binder of petroleum coke in prebaked anodes used for electrolysis of aluminum. Anodes are baked up to 1100 °C over a 20-day period, ... -
Innovative Utilization of Aluminum-Based Secondary Materials for Production of Metallurgical Silicon and Alumina-Rich Slag
Philipson, Harald; Solbakk, Gjermund L.; Wallin, Maria; Einarsrud, Kristian Etienne; Tranell, Maria Gabriella (Journal article; Peer reviewed, 2022) -
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 Behaviour in Ferroalloys: The Influence of FeMn Slag Composition
Bublik, Sergey; Tangstad, Merete; Einarsrud, Kristian Etienne (Peer reviewed; Journal article, 2022)The present study investigated the interfacial interaction between FeMn alloy and slags of different compositions and basicity from 0.4 to 1.2 in a sessile drop furnace. Interfacial tension between the FeMn alloy and the ... -
Interfacial Behaviour in Ferroalloys: The Influence of Sulfur in FeMn and SiMn Systems
Bublik, Sergey; Bao, Sarina; Tangstad, Merete; Einarsrud, Kristian Etienne (Peer reviewed; Journal article, 2021)The present study has investigated the influence of sulfur content in synthetic FeMn and SiMn from 0 to 1.00 wt pct on interfacial properties between these ferroalloys and slags. The effect of experimental parameters such ... -
Inverse modelling of interfacial tension between ferroalloy and slag using openfoam
Bublik, Sergey; Einarsrud, Kristian Etienne (Chapter, 2020)The entrainment of molten ferroalloy droplets in slag during tapping operations is strongly related to turbulence and interfacial forces between alloy and slag. Therefore, interfacial phenomena are of great importance for ... -
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 ... -
Lab Scale Experiments on Alumina Raft Formation
Gylver, Sindre Engzelius; Solheim, Asbjørn; Gudbrandsen, Henrik; Follo, Åste Hegglid; Einarsrud, Kristian Etienne (Chapter, 2020)During feeding of alumina into a Hall-Héroult cell, rafts floating on the bath surface may be formed. In this study, rafts were created in a laboratory furnace by adding 4 g secondary alumina in industrial bath. Samples ...