Preparation method for producing low-grade ferroniobium by using ferroniobium concentrate

Abstract

The invention relates to the technical field of smelting ferroalloy, in particular to a production method of low-grade ferrocolumbium by using ferrocolumbium ore concentrate. The method is that ferrocolumbium ore concentrate is taken as primary raw material, which is characterized in that the power of ferrocolumbium ore concentrate, the coal power and a little of bond are blended, heated and pressed into block; after being preheated and selective solid-state deoxidated in high-temperature furnace, the block is loaded into an electric furnace and mixed with the molten iron to get rich niobium-bearing slag and phosphorous semi-steel, the rich niobium-bearing slag, mild-phosphor molten iron, reducer and agent of fusion are put into the electric furnace, and the rich niobium-bearing slag is deeply deoxidated to produce the low-grade ferrocolumbium alloy with high ration of Nb to phosphor. The invention has the advantages of saving energy, shortening the time of process flow and improving the recovery rate of Nb.

Description

technical field [0001] The invention belongs to the technical field of ferroalloy smelting, and specifically relates to a method for producing low-grade ferro-niobium from ferro-niobium concentrate. Background technique [0002] Metal Nb has a high melting point (Tm = 2468 ℃), low electron work function, good corrosion resistance and plasticity. As a strategic resource and a scarce resource, it is widely used in metallurgy, chemical industry, machinery, electronics, Aviation, atomic and other fields, in the field of metallurgy, when the steel contains a small amount of Nb elements, the yield strength, impact toughness, processing performance, welding performance, corrosion resistance, etc. of the steel can be significantly improved. Heat-sensitive materials are also valued and favored by various related industries at home and abroad, so they need to be actively developed and utilized. [0003] The traditional ferroniobium smelting process mostly uses ferroniobium concentrat...

AI Technical Summary

Problems solved by technology

However, these mature niobium smelting processes in the past are not ideal. For example, the traditional blast furnace-converter-electric furnace smelting process route of niobium manganese ferromanganese has disadvantages such as complex process, long process, and high equipment cost. More importantly, niobium oxide NbO in minerals It cannot be fully restored, so scarce resources are not fully utilized, which is contrary to the construction of a resource-saving society, and the energy consumption of the entire process is high

However, there are also some problems in the process of smelting niobium-manganese ferromanganese that are easy to occur in the process of cold consolidation pellets-rotary kiln selective reduction-electric furnace melting deferrification and dephosphorization-electric furnace deep reduction of niobium-rich slag, first of all, in the process of raw material agglomeration A large amount of binder is added, which leads to an increase in the cost of cold-consolidated pellets and a significant increase in the amount of slag during smelting; secondly, the reduction process of cold-consolidated pellets in the rotary kiln takes a long time, and the binder is extremely high under high temperature conditions. It is prone to failure and makes the high-temperature strength of the cold-consolidated pellets worse, resulting in the occurrence of inherent accidents in the production of the rotary kiln, such as pulverization, ring formation inside the rotary kiln, etc., which reduces the equipment operating rate and affects labor productivity; the third electric furnace reduction The melting process only uses solid metallized pellets as raw materials, which makes it difficult to start the arc of the electrode, the formation of the molten pool is slow due to its poor electrical conductivity, the power consumption is high, and the recovery rate of niobium resources is low; There are disadvantages such as high smelting temperature and long smelting cycle when reducing niobium-rich slag