Phases Reconstruction and Foaming Modification of Basic Oxygen Furnace Slag on Its Grindability

Abstract

Basic oxygen furnace (BOF) slag is a main byproduct produced during the converter steelmaking process. The poor grindability of BOF slag limits its added-value application. In this paper, the grinding characteristics of unmodified and reconstructed BOF slag were compared. Additionally, the grinding property of reconstructed steel slag was also studied after SiC foaming. The results show that the solid solution of divalent metal oxides’ RO phase, considered as the hardly grinding phase, discomposes after lime-bauxite reconstruction. The characteristics of BOF slag were tested through particle size analysis, XRD, SEM and MIP. The SSA (specific suface area) and the particle diameter of unmodified BOF slag could reach 303.1 m2/kg and 51.75 µm after 10 min of grinding, but that of reconstructed BOF slag could reach 354.5 m2/kg and 18.16 µm after the same grinding time, respectively. The grinding efficiency of steel slag was obviously increased and the particle characteristics were improved after foaming modification. BOF formed as a porous structure after SiC foaming; its porosity, SSA, and particle diameter can reach 31.79%, 424.4 m2/kg, and 24.36 μm and increased by 10.31%, 19.72%, and 39.04%, compared with the reconstructed steel slag of undoped foaming agent, respectively, and the grindability was further improved. A theoretical basis for large-scale BOF slag utilization is provided.

A Review on the Carbonation of Steel Slag: Properties, Mechanism, and Application

“…Steel slag exhibits poor grindability attributed to the presence of ferrite phase. Xiang et al [31] reviewed that due Therefore, this article reviews the carbonation of steel slag based on its physicochemical properties, and factors affecting the thermodynamic and kinetic processes of carbonation are discussed. Eventually, the potential application of carbonated steel slag is summarized.…”

“…Steel slag exhibits poor grindability attributed to the presence of ferrite phase. Xiang et al [31] reviewed that due to the high content of iron oxide and MgO-MnO-FeO solid solution (RO) phase and the high absolute density with a value of approximately 3.7 g/cm 3 on average, the grindability of converter steel slag was poor.…”

Features of Processes for Preparation and Performance of Foamed Lightweight Soil with Steel Slag Micronized Powder and Granulated Blast Furnace Slag

“…This novel construction material offers advantages such as reduced weight, adjustable density and strength, and convenient construction [6][7][8][9][10]. Consequently, foamed lightweight soil, as a filling material, effectively alleviates the selfweight of the roadbed, minimizing settlement and presenting considerable prospects for widespread application [11][12][13][14].…”

“…However, during the preparation and mixing of foam light soil, part of the foam is broken because of the many edges and corners on the surface of the prepared steel slag [9]. Baalamurugan thought that steel slag morphology could be changed by grinding steel slag to reduce foam loss [10], but the grindability of steel slag is poor [14]. Hence, the balance between the fineness of steel slag and the loss of foam is worth exploring.…”