• Korean Journal of Materials Research
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• v.16 no.5
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• pp.336-340
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• 2006

Fluorspar has been essential flux in steelmaking process. The main effects of fluorspar addition are lowering of the viscosity and melting temperature of slag. In recent years, due to the increasing price and environmental problem of fluorspar, various types of fluorspar substitute have been investigated. In this study, iron oxide by-products such as sinter dust, basic oxygen furnace (BOF) sludge and mill scale were developed as a substitute in terms of waste recycling. Several plant trials were carried out by addition of briquetted substitutes of $4{\sim}6$ kg/ton to compare with the fluorspar of $0.7{\sim}1$ kg/ton. The substitutes showed a similar behavior of slag formation, phosphorus removal and MgO saturation content.

• Journal of the Korean Chemical Society
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• v.8 no.3
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• pp.109-112
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• 1964

A volumetric method of the determination of calcium carbonate and calcium fluoride in fluorspar concentrate is described. The carbonate is converted into solution by treatment of the sample in HNO$_3$-acetone (l% by volume) mixture, and the fluoride by treating the residue with H$_3BO_3$-HCl mixture. The calcium in the solution is determined volumetrically using EDTA standard solution. The selective dissolution of calcium carbonate by HNO$_3$-acetone mixture is superior to Bidtel's acetic method and little correction for the dissolution of calcium fluoride is needed. Triethanolamine is found to be superior to KCN in masking heavy metal ions.

• Resources Recycling
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• v.10 no.3
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• pp.37-42
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• 2001

Current iron and steelmaking operation was re-evaluated on the basis of slag engineering technology to optimize slag operations. In blast furnace process, increase in the basicity of slags (C/S) could obtain progressed fluidity and hot metal quality. COREX process would be stabilized in view of slag fluidity and hot metal quality by reducing input content of $SiO_2$and $A1_2$$O_3$In STS-AOD process, addition of small amount of lime could improve refining capacity of the slag; also calcium aluminate flux could be taken into account as a potential substitute for fluorspar, without degradation of operation efficiency and steel quality.

• Journal of environmental and Sanitary engineering
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• v.23 no.3
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• pp.9-22
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• 2008

This study was conducted to develop a system that processes harmful gases and dust, which being generated in the production of micro-inorganic fabric. This can be obtained by melt spinning raw materials such as agalmatolite, fluorspar, limestone, silica under high temperature at $1500-1600^{\circ}C$ in a glass recuperator using a dry method by Cyclone Reactor or Envelope Type (ET) type Bag Filter. If the number of the members of Korea Glass Industry Association reaches up to 45, the damage of the harmful gas being generated in recuperator should not be small. In addition, research of existing facilities showed the most of harmful gas treatment facilities which adopt wet treatment or semi-dry treatment process. This was caused the problems for wastewater and the second pollutive materials. Moreover, in the dust collecting facility behind recuperator, it is also problematic that electric dust collector requires enormous initial investment. We have researched various methods to show both economic and efficient new processes for the preventive facilities of recuperator. As the result of the experiments, the removal efficiencies of HF and SOx were 99% and 87%, respectively. Although it was insignificant reaction, a pretty much interesting result that NOx showed an absorption reaction with $Ca(OH)_2$(removal efficiency was more than 25%) was obtained.