Smelting technology with slag of silicon-manganese and nickel iron alloys by ore furnace

Abstract

The invention relates to a slag-containing smelting process of silicon-manganese alloy, nickel-iron alloy and other alloys by a submerged-arc furnace, comprising the steps of sintering, charging, smelting, midway deslagging, recharging, smelting, discharging and casting. The midway deslagging procedure just removes slag without discharging iron and is determined by the power load of the smelting. The slag is not fully removed during the procedures of the midway deslagging and discharging, 5%-10% of the slag remains in the submerged-arc furnace. Molten iron is not completely discharged during the discharging procedure, 5%-10% of the molten iron remains in the submerged-arc furnace. The process adopts the iron-remaining operation to keep the heat which is formerly carried away by iron tapping in the furnace and reduces heat output; therefore, the power consumption is reduced. Simultaneously, compared with the original process, the power load for the primary smelting stage is increased, the alloy percent reduction is increased a little, the speed of the smelting high-temperature reduction reaction is accelerated, and the production operation efficiency of the submerged-arc furnace is raised. The process is basically identical with the conventional process in term of the specific operation links, and the smelting process is easily controlled.

Description

1. Technical field [0001] The invention relates to a ferroalloy smelting process. 2. Background technology [0002] Ferroalloys are mainly smelted by submerged arc furnaces. The main source of heat in the ferroalloy smelting process is electrical energy. Under the current background that the country advocates energy conservation and emission reduction, increasing social benefits and economic benefits of enterprises, how to reduce the loss of electric energy in submerged arc furnace smelting is an important issue faced by ferroalloy smelting enterprises. [0003] At present, most ferroalloy smelting enterprises have taken measures to reduce the power loss of submerged arc furnace smelting, mainly to transform the power supply facilities of submerged arc furnace, improve the efficiency of electrical equipment of transformers, select transformers with small no-load loss and transform short network, reduce Loop impedance and inductance etc. Relatively from the perspective of ...

AI Technical Summary

Problems solved by technology

[0004] Judging from the current process of smelting silicon-manganese alloys and nickel-iron alloys with submerged arc furnaces, the iron-tapping intervals during the smelting process are short and relatively frequent, which is not conducive to the smooth progress of electrode insertion and smelting. Take some precious heat, when the next batch of cold material is loaded, it will take more power to complete the normal smelting heating process

Complete iron tapping will also result in low power consumption in the early stage of smelting, and the power load cannot reach a high level. In ferronickel production, sometimes one phase of the three-phase electrodes even has no load within 40 minutes after the furnace is completed.

As a result, the melting speed of the furnace material is slow, the furnace feeds slowly, and the melting time is long, resulting in excessive power consumption in the entire alloy smelting process

[0005] In addition, the relatively frequent tapping of iron makes the temperature fluctuations in the submerged arc furnace large and low during the entire alloy smelting process. In the early stage of smelting, the power load is insufficient, the power density at the bottom of the furnace is insufficient, and the high-temperature reducing atmosphere of alloy elements is relatively weak, resulting in alloy The reduction output rate has decreased, and the alloy output cannot increase

[0006] Therefore, the slag smelting process of traditional submerged arc furnaces for smelting alloys such as silicon-manganese and nickel-iron generally has the problems of high energy consumption and low output.