Three-phase alternating-current ore smelting furnace and method for controlling furnace condition thereof

Abstract

The invention discloses a method for controlling a furnace condition of a three-phase alternating-current ore smelting furnace. Electrodes are vertically arranged in a hearth of the three-phase alternating-current ore smelting furnace, a burden layer in the hearth is longitudinally divided into a plurality of smelting zones, the smelting zones are insulated from one another, and each smelting zone corresponds to one electrode. The invention further discloses the three-phase alternating-current ore smelting furnace which comprises the electrodes and high-temperature-resistant insulation devices. The electrodes are vertically arranged in the hearth of the three-phase alternating-current ore smelting furnace, the high-temperature-resistant insulation devices are arranged in the hearth, the corresponding burden layer of the hearth is longitudinally divided into the multiple smelting zones by the high-temperature-resistant insulation devices, accordingly, the smelting zones are insulated from one another, and each smelting zone corresponds to the corresponding single electrode. The method and the three-phase alternating-current ore smelting furnace have the advantages that the problem of influence of branch currents of a burden layer on running of an existing three-phase alternating-current ore smelting furnace can be solved by the method and the three-phase alternating-current ore smelting furnace, the stability of the furnace condition can be improved, secondary running voltages of the three-phase alternating-current ore smelting furnace can be increased, electric energy of reaction zones of lower ends of the electrodes can be greatly increased, unit energy consumption of products can be reduced, and the yield of the products can be increased.

Description

technical field [0001] The invention relates to a method for controlling the furnace condition of a submerged arc furnace and the submerged arc furnace, in particular to a method for controlling the condition of a three-phase AC submerged arc furnace and a three-phase AC submerged arc furnace. Background technique [0002] Three-phase AC submerged arc furnace is a kind of submerged arc furnace. The smelted products include silicon-based, chromium-based, manganese-based and other ferroalloys, calcium carbide, yellow phosphorus, etc. When working, the electrodes are inserted into the furnace charge in the furnace to implement submerged arc Operation, the electric energy is input into the furnace through the electrode, and the arc generated between the end of the electrode and the charge and the resistance heat of the charge are used as the heat source for heating, so it is also called resistance electric arc furnace. After the charge is melted, it is divided into three layers ...

AI Technical Summary

Problems solved by technology

For the three-phase AC submerged arc furnace, with the change of charge and method operation, the resistance of the charge layer, the temperature of the charge layer, the gas permeability of the charge layer, etc. will also change, and the resistance characteristics of the charge layer will also change, resulting in repeated furnace conditions. A little carelessness will cause the furnace condition to deteriorate, the electrode will not fall, the temperature of the bottom of the furnace is not enough, and it will be difficult to release the furnace. At this time, it is reflected from the instrument that the current fluctuates greatly and the transformer gear is low (the secondary voltage of the electric furnace is biased). Low), the power factor of the electric furnace is low, the electrode rises and falls frequently, and the phenomenon in the furnace is: the furnace material layer is overheated (the furnace material surface is crusted, the furnace material surface is full of red materials, and local melting holes are formed), the material is seriously collapsed, and the temperature of the furnace gas is high. , the electrode is lifted seriously, and the furnace temperature is low; when it comes out of the furnace, it shows that the liquid product is not smooth, the flow rate is slow, the product is sticky and easy to block the furnace hole, and the round steel cannot reach the center of the furnace when the hole is pierced. High energy consumption and low output make operators feel very troubled by this. The main reasons for this result are: the poor electrical conductivity of the cold charge, the molten mixture is a good conductor, and the resistance characteristic of the mixed charge is that the resistance increases with the increase of temperature. When the furnace material layer is overheated, the current in the branch circuit of the furnace material layer is too large, which affects the stable operation of the electrode and leads to poor stability of the furnace condition. This feature determines the complexity and difficulty of the three-phase AC submerged arc furnace condition control , and it is also the reason why many pioneers engaged in the furnace condition control of submerged arc furnaces have not succeeded so far

[0003] In order to improve the unstable condition of the three-phase AC submerged arc furnace, which leads to high energy consumption per unit and low output, the traditional method is to strengthen the maintenance of the charge surface, adjust the formula, strengthen the furnace, adjust the secondary operating voltage, and lift the electrode, etc. However, these measures are only taken passively when the furnace condition shows a deteriorating trend or has already deteriorated. These measures have to go through a period of adjustment from the implementation to the normal furnace condition, or when the furnace condition is judged inaccurately and When improper treatment measures are adopted, the furnace condition will further deteriorate. This is done entirely by the practical experience of the method operator, which also causes the strange phenomenon that the furnace condition varies from person to person. Therefore, the traditional method is unstable to the furnace condition. The effect of problem improvement is not very satisfactory, so that there are still problems of high energy consumption per unit of product and low output

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