The viscous behavior of CaO–SiO2–FeO–MgO slags saturated with dicalcium silicate (2CaO·SiO2) with 8 mass% MgO at 1873 K, and CaO–SiO2–FeO–Al2O3–MgO slags are measured under the conditions of highly basic slag compositions with regard to the fluidity of BOF slag and slag coating technology. The experiment shows that slag viscosities increase with decreasing temperature for almost all the slags that have been investigated over a range of temperature range, and the slag viscosity has exhibited different behavior in the temperature range lower and higher than 1773 K. The viscosity of the present slag systems has decreased with increasing FeO content. The viscosities depended on Al2O3 and FeO contents more strongly than on MgO content. The slag basicity has a more significant effect on increasing slag viscosity. A thermodynamic approach for the constants of the Einstein–Roscoe equation has resulted in a reasonable relationship between the relative viscosity and the volume fractions of solid phases estimated from the slag compositions. Thus, the present study confirms that the viscosities of highly basic slags can be estimated in terms of the slag compositions by predicting the fraction of solid phases in the slags for the stable BOF operation and the reliable coating of vessel lining.

Viscosity of Highly Basic Slags

An electric furnace comprising a container having electrically isolated wall segments useful for melting materials, particlularly ceramics, is disclosed. The electric fornace's side walls are constructed from electrically isolated segments, which cause electric current from a plasma torch to be concentrated on the material in the furnace to be melted rather than diverted to the walls of the furnace.

Segmented electric furnace

In a copper converting furnace, the (i) reduction of copper oxide in and the removal of copper metal from the slag, and (ii) conversion of copper sulfide in and the elimination of mineral waste from the blister copper is enhanced by introducing a gas, e.g. nitrogen, into at least one of the blister copper and slag such that the gas increases the turbulence or mixing at the blister copper/slag interface and promotes a lowering of the sulfur dioxide equilibrium pressure within the blister copper and slag phases. In one embodiment, the gas is introduced into both the molten blister copper and slag through a porous-wall injector.

Enhanced phase interaction at the interface of molten slag and blister copper, and an apparatus for promoting same

During the last decades, the continuous casting process has made enormous advances and more than 90% of the world steel production is now continuously cast [1]. In this process, the liquid steel is poured into a water-cooled copper mould through a submerged entry noz‐ zle (SEN), see Figure 1 [2]. At this stage the solidification process begins. In this way semi‐ finished products with specific characteristics such as slabs and billets are obtained. During this process the mould fluxes perform several critical functions to obtain products with the quality required.

https://www.intechopen.com/citation-pdf-url/38132

Mould Fluxes in the Steel Continuous Casting Process

A method and apparatus for processing a contaminated free-flowing material and, in particular, filter dust from industrial metallurgical waste and domestic waste incineration plants are disclosed. In order to ensure that the end product of the plant can be reused or disposed of in an environmentally sound manner, the free-flowing material is mixed in the dry state with a reducing agent; the resulting mixture is inserted through the bore of a hollow electrode extending into a metallurgical vessel, so that the interior end of the electrode is immersed in the slag in the vessel, and the mixture is pneumatically injected through the electrode into the molten slag; heat is supplied to the mixture during the reaction between the mixture and the slag; evaporated components of the mixture are exhausted from the vessel; mixture components precipitated into the molten metal are tapped together with the molten metal; and the remaining components of the mixture which remain in the slag are discharged from the vessel together with the slag. The throughbore of the hollow electrode is connected to an arrangement for feeding and discharging gaseous media into the electrode. A power supply system includes components for maintaining a constant current and for regulating the electrical output thereof.

Method and device for processing free-flowing materials

A process for treating metal comprises applying a positive DC potential to an ionic melt layer disposed on the surface of a liquid metal. The application of this potential provides a plasma phase above the ionic melt layer and induces a flow of electrons from the liquid metal towards the plasma phase. The ionic melt layer is capable of being maintained in a liquid state when it is in contact with the liquid metal. The process can be used either to remove impurities from the liquid metal, to alloy the liquid metal by adding metal compounds in the ionic melt layer, to recover metals from waste, or to perform a combination of these functions. An apparatus for treating liquid metals is also provided.

Process for treating liquid metals

During continuous casting of steel, the properties of mold fluxes strongly affect the casting performance, steel quality and environment of casting operation. The high temperature microscopy technique was used to investigate the melting behaviour of mold fluxes, and drip test method was used to determine their melting rate. The results showed that free carbon is a dominant factor in governing the melting behaviour of fluxes, and the melting rate is increased with increasing carbon reactivity and decreasing carbon content.

Effect of Carbon Properties on Melting Behavior of Mold Fluxes for Continuous Casting of Steels

Experiments were carried out at 1175-1350°C to study the phosphate capacity of CaO-CaCl 2 slags and the sulphide capacity was calculated according to the correlation between the two capacities. At 1200°C the logarithm of the phosphate capacity increased from 24.5 to 26.5 with increasing CaO mole fraction from 0 to 0.22 in the slags and it decreased with increasing temperature. Sulphide capacity increased both with increasing CaO mole fraction and temperature. A good linear correlation was found between slag carbonate capacity and phosphate capacity as well as sulphide capacity. Optical basicity was used to evaluate the property of the CaO-CaCl 2 slag in the present study. The value of optical basicity of CaCl 2 is established as 0.63. The correlations of optical basicity with above mentioned three capacities were found to be linear

I.D. Sommerville

Papers

Process for treating liquid metals

Effect of Carbon Properties on Melting Behavior of Mold Fluxes for Continuous Casting of Steels

Study on phosphate and sulphide capacities of CaO-CaCl2 slags

Phosphate and sulphide capacities of CaO-CaCl2-CaF2 slags

Liquid steel transfer—the delivery of quality