REWAS 2022:Decarbonizing the Materials Industry: Alternative Reduction and Carburization Sources
Sponsored by: TMS Extraction and Processing Division, TMS: Recycling and Environmental Technologies Committee, TMS: Energy Committee, TMS: Process Technology and Modeling Committee, TMS: Aluminum Committee
Program Organizers: Camille Fleuriault, Eramet Norway; Christina Meskers, SINTEF; Mertol Gokelma, Izmir Institute of Technology; Elsa Olivetti, Massachusetts Institute of Technology; Jesse White, KTH Royal Institute of Technology; Chukwunwike Iloeje, Argonne National Laboratory; Neale Neelameggham, IND LLC; Kaka Ma, Colorado State University

Tuesday 2:30 PM
March 1, 2022
Room: 212A
Location: Anaheim Convention Center

Session Chair: Jesse White, KTH Royal Institute of Technology

2:30 PM Introductory Comments

2:35 PM  Invited
HIsarna: A Technology to Meet Both the Climate and Circularity Challenges for the Iron and Steel Industry: Johan van Boggelen1; 1Tata Steel
     Over the past decade the European Union has set the ambition to become a carbon neutral and fully circular economy. To achieve this, it will be necessary to develop new technologies and processes that address both issues simultaneously. In this paper the HIsarna ironmaking technology is used as an example where the reduction of CO2 emissions, the use of secondary raw materials as well as the valorisation of by-product streams is considered in the early stages of the process development.In the light of climate change, sustainability, resource efficiency and circularity these aspects should be part of the considerations for any new process being developed, even if their economic viability still needs to be established.

3:05 PM  
Tecno-economic Pre-feasibility Study of a Hydrogen Plasma Based Ferromanganese Plant: Halvor Dalaker1; Nils Eldrup1; Roar Jensen1; Rannveig Kvande1; 1Sintef
     Hydrogen is a candidate to replace carbon in metal production, as it can reduce some metal ores (e.g. iron ore); MeOx + XH2(g) = Me + XH2O(g). However, many metals, like manganese (Mn), cannot easily be reduced by H2(g) since very high activation energies are required to break the metal-oxide bond. By using hydrogen in the plasma state rather than the gas-phase, the reactivity of the hydrogen species increase significantly. For example, reduction of manganese by monoatomic hydrogen is thermodynamically favourable: MnO + 2H = Mn + H2OA prerequisite for the introduction of hydrogen plasma in metal production is a good financial case. In this work we present a scheme for a possible industrial scale ferromanganese plant based on hydrogen plasma reduction. Through mass and energy balances we demonstrate that such a plant can be economically competitive with current industrial state of the art.

3:25 PM  Invited
PreMa-project Development of New Technologies to Reduce CO2 Emissions in Mn-alloy Production : Eli Ringdalen1; 1Sintef
     PreMa is an EU Horizon 2020 project developing technologies to reduce CO2 emissions and consumption of electrical energy in Mn-alloy production. The main concept is to pretreat Mn-ores in a separate unit prior to final alloy production in submerged arc furnace. Various pretreatment technologies using different energy sources like CO-rich industrial off-gas, bio-carbon and solar thermal are investigated and will be developed and demonstrated. Investigations of selected industrial Mn-ores are done on different scales. Kinetic parameters are determined and effect of various pretreatment conditions on industrial materials are investigated in laboratory scale. Different pretreatment technologies and subsequent alloy production from produced materials are tested in pilot scale. Environmental effects are assessed, and process flow sheets compared by modelling. The paper gives an overview over the process concept, how the different parts are linked, and main results from the investigations.

3:55 PM Break

4:15 PM  
Towards Green Ferroalloys: Replacement of Fossil Reductants in the Pre-reduction Process of Chromite by Bio-based Alternatives: Marcus Sommerfeld1; Bernd Friedrich1; 1IME Process Metallurgy and Metal Recycling, Institute of RWTH Aachen University
    The production of ferrochrome via carbothermic reduction in submerged arc furnaces is an energy-intensive process relying on the usage of coal and coke as reducing agents. The pre-reduction of chromite in a rotary kiln is currently carried out to decrease the specific electric energy consumption in the smelting furnace. However, as fossil reductants are still needed for reduction, CO2 is emitted. The usage of bio-based carbon with a faster carbon cycle compared to fossil reductants could be an option to decrease the specific CO2-footprint of ferrochrome production. In this paper, the pre-reduction of chromite was investigated using various bio-based reducing agents and lignite coke as a fossil reference. Isothermal reduction trials were conducted at 1000 C, 1150 C and 1300 C and different reaction times. X-ray diffraction was carried out to investigate the obtained product.

4:35 PM  Invited
Pyrometallurgy-based Research Conducted at Mintek towards Decarbonizing the Metals Industry: Joalet Steenkamp1; Pieter Johannes Andries Bezuidenhouta2; Itumeleng Thobadi2; Lunia Malaka2; Susanna Hockaday3; Glen Michael Denton2; Buhle Xakalashe2; Elias Matinde1; Thokozile Penelope Kekana2; Sonwabo Bambazala2; Aditya Kale2; Quinn Gareth Reynolds4; 1Mintek; University of the Witwatersrand; 2Mintek; 3University of Stellenbosch; 4Mintek; University of Stellenbosch
    One of the focus areas for research conducted by the Pyrometallurgy Division at Mintek in South Africa is decarbonisation of the metals industry. In a country with a large Pyrometallurgical industry, based primarily on carbonaceous primary reduction processes and electricity generated primarily by coal-fired power stations, the challenge can be viewed from a number of perspectives. The paper will provide a summary of the projects currently underway, where the Technology Readiness Levels (TRL) ranges from TRL 1 to TRL6.

5:05 PM  
Solid Oxide Membrane (SOM) Based Technology for Carbon-free Efficient Production of Solar-grade Silicon: Haoxuan Yan1; Michelle Sugimoto1; Uday Pal1; Adam Powell2; 1Boston University; 2Worcester Polytechnic Institute
    State-of-the-art Solar-grade silicon production is energy intensive and has a negative impact on the environment. Due to the robust and rapid growth of the Si-based photovoltaic (PV) industry, it is necessary to develop a greener technology for Silicon production. Solid oxide membrane (SOM) electrolysis is a proven versatile green technology that can be developed to economically produce many important metal or metal compounds from their oxides. This work will discuss application of SOM electrolysis to produce solar-grade silicon from silica in a single-step resulting in net-zero-carbon emission. The high-temperature SOM electrolysis cell employs stable molten oxide-fluoride bath with silicon wafer cathode and stabilized zirconia membrane-based novel anodes. The cell design and process parameters are selected to enable uniform and dense Silicon deposition on the Si-wafer cathode. Electrochemical characterization of the process will be presented.