Composite additive for sintering iron ore powder and method of manufacturing the same

Abstract

The invention relates to a compound additive for sintering iron ore powder and a preparation method thereof, and provides the following technical scheme: the compound additive is prepared by evenly stirring the following raw materials: 30wt% to 50 wt% of combustion-supporting agent, 15wt% to 25wt% of oxygen-increasing agent, 3wt% to 10wt% of strengthener, 10wt% to 20wt% of catalytic agent, 5wt% to 10wt% of coarse rice hull, 5wt% to 10wt% of calcium fluoride, 2wt% to 5wt% of SHN pellet binder and 5wt% to 10wt% of boric anhydride. The invention has the characteristics of simple preparation process and low cost; and by applying the prepared compound additive in sintering the iron ore powder, the vertical sintering speed can be increased by more than 12%, the production yield can be increased by more than 4%, the tumbler index can be increased by more than 5%, the sintering iron grade can be improved by 1 to 1.5, the fuel consumption can be reduced by more than 10%, the emission of SO2 can further be reduced and the compound additive is free from materials causing damage on blast furnace production, such as K, Na and other elements, therefore, the invention can improve the air permeability of sintering beds, increasing the combustion speed and the reaction speed of the mineralizing process and improving the yield and the quality of the sintering ore.

Description

technical field [0001] The invention belongs to the technical field of metallurgical iron ore powder sintering. In particular, it relates to a composite additive for iron ore powder sintering and a preparation method thereof. Background technique [0002] Iron ore powder sintering is a mineralization process involving complex physical and chemical reactions, including solid phase reaction and new phase formation at low temperature, binder phase and liquid phase formation at high temperature, and Condensation, recrystallization and phase change processes formed during cooling. Therefore, there are many factors affecting sintering mineralization and consolidation, such as mineral type, ingredient combination, raw material particle size, mixture moisture, alkalinity, fuel addition amount, ignition temperature, sintering negative pressure, material layer height and cooling method, etc. [0003] With the rapid development of the iron and steel industry, resources and energy are...

AI Technical Summary

Problems solved by technology

According to the industrial tests conducted by some domestic sintering plants, these sintering additives have certain effects in increasing the strength and output of sintering ore and reducing energy consumption, but there are still some unresolved problems, such as: the chemical composition of some additives is: oxidizing agent Sodium nitrate (NaNO 3 ), potassium permanganate (KMnO 4 ), potassium nitrate (KNO 3 ), etc.; catalysts include sodium chloride (NaCl), potassium chloride (KCl), sodium carbonate (NaCO 3 ), etc.; zinc oxide (ZnO), sodium borate (NaB 4 o 7 10H 2 O), etc.; binders include bentonite, etc. Most of these chemical compositions contain K, Na, Zn, Si, Al and other elements that are harmful to blast furnace smelting, and even contain substances that will have adverse effects on the environment. The ore is brought into the blast furnace and enriched in a cycle in the furnace, which has a great adverse effect on the life of the blast furnace lining and technical and economic indicators