SU1643507A1 - Method of production of high-refractory fused material - Google Patents

Abstract

This invention relates to the production of highly inelastic fused material. The purpose of the invention is to reduce the cost of the gas, expand the raw material base, increase the economic performance of the process and stabilize the component composition of the material obtained. This is achieved by first conducting the ore recovery of the poor alumina raw material, removing the ferrosilicon, and adding to the corundum melt mdgnezit, then 8-16 wt.% of the magnesia-zirconium composition of the eutectic composition are injected into the melt of the obtained spinel, incubated for 15-25 minutes, 8-16 wt.% of the eutec magnesiyl-chromium composition are introduced. tic composition, incubated for 5-10 min and poured into molds. Electricity consumption 2840-3250 kWh / t. 1 tab.

Description

The invention relates to the manufacture of refractories for metallurgical plants and glass melting furnaces.

The aim of the invention is to reduce the cost of the charge, expand the raw material base, increase the technical and economic indicators of the process and stabilize the component composition of the material obtained.

The method is as follows.

A primary melt of aluminum magnesia spinel is obtained: alumina raw materials with an Al content of less than 40 wt.% — Clay, kaolin, etc. Natural aluminosilicates blend with a carbon-containing component. (The obtained agglomerate or briquettes are subjected to ore-smelting smelting in electric furnaces with the addition of cast iron chips to the resulting melt.

the electric smelting of agglomerate or briquettes consisting of a mixture of initial components, in the presence of iron, silicon is reduced long before the restoration of the main component (). and, combined with iron, forms a ferrosilicon melt which separates with the melt of the melted material due to mutual non-dissolvability and a difference in specific mass. The resulting ferrosilicon release through the tap hole, located in the lower part of the bath furnace. After the release of ferrosilicon from the electric furnace, magnesite powder is introduced into the corundum melt with a temperature of 2200 ° C to obtain a melt of aluminum-magnesium spinel of stoichiometric composition of 72 wt.% And May 28, MgO.

. After that, it was deciduous.

Spinel injected pre-prepared magnesia-zirconium composition of eutectic composition (50 mol,% MgO, 50 mol.%. 2gO) in an amount of 8-16 wt.% in the form of granules or pieces of irregular shape with a size of 5-20 mm . After holding the melt for 15–25 min, the magneto-chromium composition of the eutectic composition (40 mol.% MgO, 60 mol.%) In an amount of 8–16 wt.% Is introduced in the form of granules or pieces of irregular shape with a size of 5 -20 mm. After that, the melt is kept for 5-10 minutes, poured into molds and cooled at an arbitrary rate.

Batching the introduction of MgO in the composition of eutectic compositions into the melt of alumino magnesia spinel is due to the fact that a sufficiently high fluidity of the melt is maintained, allowing for the production of stabilized component fused material. MgO has a melting point of 2800 ° C, ZrO is 26806С, and the eutectic is MgO - 2yr (50 to 50 mol.%) Has so-pl. 2150 ° C. When a magnesia-zirconium composition of eutectic composition is introduced into the melt instead of a mechanical mixture of MgO and Zr02, the degree of evaporation of MgO decreases both by reducing the assimilation time of the additive due to the lower melting point, and because MgO is in the form of alloy eutectic composition.

In a similar way, the assimilation of MgO by the melt of aluminum magnesia is improved.

oval spinel when entering it in the form

magnesia-chromic composition of eutectic composition (8-16 May,%): so pl. MgO 2800 ° C, so pl. Cr 203 2300 C m.p. eutectic MgO - (40 to 60 mol.%) 2250 ° C, it also increases the degree of absorption of Cr203 and reduces the degree of reduction to chromium metal.

The pre-calcined bauxite with a particle size of 2-0, mm of the following chemical composition,% is set into the charge: A1203 59.0; SiOa 8.0; 24.2; Ti02 2.4; CaO 1.18; ppt 6.0.

A sulfite-alcohol bard (density 1.18 g / cm9) is used as a binder. The composition of the briquetting mixture is introduced into the ground (16 µm) low-coking angle in an amount that provides

d

Q Q

five

0

five

0

dim reduction of impurity oxides by carbon during electrofusion.

The weighed components of the mixture are mixed in a ganek mixer with the gradual introduction of sulfite-alcohol bards. The resulting mixture is bri-ketiru on a two-roller roller press. The briquettes are naturally dried to a moisture content of 1.6% and then smelted in a 250 kVA large-laboratory electric furnace. Melting is carried out by a periodic process with full penetration of the charge and release of the melt of ferrosilicon into graphite molds. The current load is gained at the sixth step (71.3 V), simultaneously loading the charge. After the top furnace has been melted in order to warm up the melt, the furnace is transferred to the fourth transformer voltage level (49.6 V). The degree of melt heating is determined by the thickness of the rod samples. When the normal coriculate fluidity of the electrocorundum is reached, magnesite powder is applied to it at the rate of obtaining a melt of aluminum-magnesium spinel of stoichiometric composition: 72 wt.% AlgCVj and 28 wt.% MgO. After full absorption of the magnesite powder, the previously prepared magnesia-zirconium composition of the eutectic composition in solid form is introduced into the resulting alumina-magnesia spinel melt, after which the furnace is transferred to the fourth step (49.6 V) voltage. After holding, the electric furnace is transferred to the sixth step of the transformer voltage (71.3 V) and the previously prepared magnesia-chromic composition of the eutectic composition is introduced in solid form, after which the furnace is transferred to the fourth step of the voltage (49.6 V) and maintained. The obtained high-alloyed melt A120 - MgO - CrЈ05-ZrO, g is poured into molds.

The values of the bottoms for the production of highly refractory fused material are given in the table.

The technical and economic efficiency of the proposed method lies in the fact that the process of obtaining highly refractory fused material is cheapened both by using poor alumina raw material to produce an aluminum-magnesium spinel melt, and as a result of reducing energy consumption during heat recovery from aluminum silicate aluminosilicates, which allowed reduce electricity by 500-600 kW / h (compared to a known method),

Claims (1)

Invention Formula The method of obtaining high-refractory fused material, including obtaining a homogeneous melt expanding the raw material base, improving the technical and economic indicators of the process and stabilizing the component composition of the material obtained, first carry out the ore recovery of the poor alumina raw material, remove the ferrosilicon, and add magnesite to the corundum melt, then add 8-16 wt. to the melted aluminum magnesia spinel. % magnesian-zirconium composition of the eutectic composition, hold Impurities 8.6.