Direct current electric arc furnace bottom electrode structure and application thereof

Abstract

The invention relates to a direct current electric arc furnace bottom electrode structure. A bottom electrode structure is a composite bottom anode structure. The bottom electrode structure comprises a plurality of metal conduction elements vertically installed at the furnace bottom at intervals. The intervals between the metal conduction elements are filled with fireproof materials. The lower portions of the intervals are filled with non-conduction fireproof materials. The upper portions of the intervals are filled with first conduction fireproof materials. A layer of second conduction fireproof material is laid on the top of each metal conduction element. The second conduction fireproof materials are used for heat repairing. The invention further relates to application of the direct current electric arc furnace bottom electrode structure. By adoption of the conduction fireproof materials, a metal bottom anode is changed into a composite bottom anode in which metal and the conduction fireproof materials are combined, a metal bottom anode which cannot be repaired is changed into a bottom anode capable of being subjected to cold state repairing and heat state repairing, and therefore the service life of the bottom anode is greatly prolonged, the operation rate of steelmaking of an electric furnace is increased, the steelmaking cost is reduced, and the equipment utilization rate is increased.

Description

technical field [0001] The invention relates to the technical field of a DC electric arc furnace, in particular to a DC electric arc furnace bottom anode, in particular to a DC electric arc furnace bottom electrode structure and its application. Background technique [0002] So far, there are four types of DC arc furnaces: [0003] (1) ABB type: The entire bottom of the furnace is built with conductive magnesia-carbon materials. This structure has the following undesirable results: a) Its ideal state is that the current is evenly distributed at the bottom of the furnace, but in fact this is difficult to achieve. In the process of construction and use, especially after hot repair, it is difficult to achieve uniform thickness and consistent density of the furnace bottom. In addition, the current has the characteristics of a low-resistance channel, so the current density distribution at the bottom of the electric furnace is uneven. In the center of the furnace bottom (right ...

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Problems solved by technology

This structure has the following disadvantages: a) The current is only concentrated in the center of the furnace bottom, which causes the center of the furnace bottom to overheat and the molten steel to flow rapidly, and the electrode part of the furnace bottom cannot be hot repaired, so the service life of the bottom electrode is relatively low, generally only 500~ 1500 heats

This cannot be used as an electrode material, or it cannot guarantee the normal operation of the DC electric furnace at all, or even cannot operate; 3) In the case where the bulk material composed of magnesia carbon brick, magnesia and graphite cannot operate, it is either non-conductive or weak Conductivity and may be broken down at any time, causing the graphite block to be exposed to the molten steel, which will quickly dissolve the graphite block into the molten steel, resulting in the formation of a large pit under the electrode, the furnace bottom temperature is too high, and safety accidents may occur Appear at any time; 4) Whether there is a strong static fit between the graphite block and the metal rod, coupled with the large difference in thermal expansion between the two, this may lead to a large interface resistance, which will cause the bottom of the furnace to heat up and cause the electrode to wear out too quickly , very short service life

In short, such DC arc furnace bottom anode either cannot work, or even if it can work, it may lead to excessive consumption of the bottom anode, high furnace bottom temperature and short service life

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