Slag high-heat-strength blast-furnace magnesium filler

Abstract

The invention discloses a slag high-heat-strength blast-furnace magnesium filler which is prepared from the following raw materials in percentage by mass: 70-90% of light-burned magnesium powder, 1-8% of binding agent, 5-12% of aggregate and 2-11% of water. The slag high-heat-strength blast-furnace magnesium filler comprises the following components in percentage by mass: 60-75% of MgO, 4-14% of SiO2, 2-6% of CaO, 2-8% of H2O, and 12-17% of binding agent and other components. The raw materials are pressed into oblate spheroids under the mechanical force of a briquetting machine; and the physical dimension of the oblate spheroid magnesium filler is 35-65mm, and the compression strength at room temperature is 1500-3500N. The magnesium filler has the advantages of small volume and high compression strength, is convenient for addition, does not increase the thermal energy consumption of the blast-furnace smelting, improves the comprehensive metallurgical properties of furnace slag, relieves the wind resistance of the blast furnace, promotes the yield increase, consumption reduction and effect enhancement of the blast furnace, and enhances the economic benefit of the blast furnace.

Description

technical field [0001] The invention relates to a flux used in blast furnace ironmaking, in particular to a magnesium filler which is mechanically pressed and formed by high-grade magnesium oxide powder, aggregate, binder, etc. under a specific ratio. Background technique [0002] Blast furnace slagging is an important part of blast furnace ironmaking, and flux is an important component of raw materials for blast furnace slagging. Whether the blast furnace can maintain long-term stable and smooth production is closely related to the performance of the blast furnace slag, and the performance of the slag is affected by many factors, the most important of which is the composition of the slag. In recent years, the low-cost iron ore fines in the ore blending of domestic iron and steel enterprises has increased year by year, making the A1 with a high melting point in the blast furnace slag 2 o 3 The content is greatly increased, which exceeds the normal requirements of blast fur...

AI Technical Summary

Problems solved by technology

[0003] The magnesium oxide content in the blast furnace slag of most domestic iron and steel enterprises is directly determined by the magnesium oxide content in the sintered ore. If the requirements for the magnesium oxide content of the blast furnace are to be met, the quality of the finished product of the sintered ore cannot be guaranteed, and the productivity of the sintering machine will be greatly reduced.

If the traditional method is adopted—dolomite or magnesite whose main components are calcium carbonate and magnesium carbonate are directly fed into the blast furnace, the carbon dioxide generated during the thermal decomposition of the incidental carbonate radicals will cause a decrease in the utilization rate of the chemical energy of the gas, As a result, the carbon efficiency is reduced, the direct reduction rate is increased, and the coke ratio is significantly increased, and the strength of dolomite or magnesite after light burning is low, and it is easy to be pulverized prematurely, which makes the air permeability of the blast furnace worse, resulting in abnormal conditions of the blast furnace