N x represents the weighted mole fraction of the different slag components.
Electroslag remelting (ESR) is a well-established secondary refining process for many steels and Ni-base alloys with highest requirements regarding material properties. The main purposes are a dense solidification of ingots with a low degree of segregation as well as the reduction of medium-sized and especially complete removal of large nonmetallic inclusions (NMI). The specific energy consumption of ESR is documented in the range from 880 to over 2000 kWh t À1 . [1][2][3][4][5][6][7] Rising requirements regarding sustainability, emission control, and environmental protection have triggered new awareness for this topic. [4,8,9] Besides plant geometry and design, the customarily CaF 2 -based slag plays the key role in the heat generation and energy consumption of ESR. Key properties are the melting point as well as the electrical and thermal conductivity. [2,10] Other factors such as fill ratio and the amount of slag, or the melt rate can also have a strong effect. [4,8,[11][12][13][14][15][16] According to Holzgruber, [16] rising fill ratios up to 0.4 lead to a reduction in specific energy consumption due to a better heat transfer into the electrode and less radiation losses at the free slag surface. A further increase in fill ratio surprisingly resulted in a reversed trend due to changing immersion depths. Results from Li et al., [14] both laboratory scale and industrial size, demonstrate the strong effects of fill ratio (0.24 and 0.6) and electrical conductivity on the specific energy consumption with values below 1000 kWh t À1 at higher fill ratios combined with low or no CaF 2 -containing slags. CaF 2 -free slags in Brückmann and Schwerdtfeger [17] confirmed their particular advantage in specific energy consumption with values below 1000 kWh t À1 .There are only few reports of systematic research on energy consumption in ESR on the industrial scale. A recent investigation with a wider variation of slags is documented in refs. [5][6][7], and confirms an almost linear increase with electrical conductivity. A similar but less pronounced increase is reported in Jäger and Kühnelt [18] for slag composition with a wide variety of CaF 2 contents and a significantly higher fill ratio. A recent summary on the different effects of the fill ratio and the electrical conductivity on the specific energy consumption can be found in Schneider et al., [4] indicating that the energy consumption data from laboratory scale
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.