Method for controlling slag overflow in converter tapping process

Abstract

The invention belongs to the field of converter steelmaking systems, and relates to a method for controlling slag overflow in the converter tapping process. The method comprises the following steps that after converter blowing is finished, dolomite is added into a converter mouth through an overhead bunker; a converter oxygen lance is lowered to the position of 4 m, and high-pressure nitrogen is used for purging a slag surface for 20-30 seconds; after the slag surface is purged by the high-pressure nitrogen, the lance position of the oxygen lance is lifted, and the slag surface is purged for 10 seconds; and in the tapping process of a converter body, cooling slag pressing materials are added to the slag surface of a converter dispersedly through a cooling slag pressing material feeding vehicle right opposite to the converter mouth until tapping of the converter is finished. According to the method, slag overflow during steel tapping is controlled through the steps of adding the dolomite before steel tapping to reduce slag foaming, conducting gas purging for diluting the slag, adding the cooling slag pressing materials during steel tapping to press the slag and actively receiving the slag after slag overflow happens; and due to good slag overflow control, in the converter steel tapping process, the steps of forward pouring of the converter for temperature measurement, sampling and slag pouring can be omitted, the smelting time is saved by 2.5 minutes, and meanwhile, the production cost is reduced.

Description

technical field [0001] The invention belongs to the field of converter steelmaking systems, and relates to a method for controlling slag overflow in the converter steel tapping process. Background technique [0002] The conventional smelting process of converter smelting is: blowing - turning the furnace forward for temperature measurement and sampling and dumping slag - turning the furnace backward for tapping. During the tapping process, the molten steel in the furnace flows into the ladle through the tapping port, and the slag is controlled to stay in the furnace. If the slag foam is serious, the slag will overflow from the furnace port. The main hazard is that the high-temperature slag will burn the related equipment and facilities of the converter. More seriously, it will even injure the operator behind the furnace, and the overflow of slag into the ladle will cause an accident of the P component of the molten steel. [0003] Conventional slag overflow control technolo...

AI Technical Summary

Problems solved by technology

During the tapping process, the molten steel in the furnace flows into the ladle through the tapping port, and the slag is controlled to stay in the furnace. If the slag foam is serious, the slag will overflow from the furnace port. The main hazard is that the high-temperature slag will burn the related equipment and facilities of the converter. More seriously, it may even injure the operators behind the furnace, and the overflow of slag into the ladle will cause accidents in which the P component of the molten steel is out of order.

[0003] Conventional slag overflow control technology is: before the start of converter tapping, the converter body is transferred to the front of the furnace for temperature measurement and sampling, and at the same time, the slag dumping operation is performed to reduce the amount of slag. %, so as to reduce the risk of slag overflow during the tapping process of the converter. The disadvantage of this technology is that it takes about 3 minutes for the converter to move forward to measure the temperature, take samples and dump the slag, which will have a certain impact on the overall smelting rhythm of the converter.

The patents "Slag overflow control method, device, equipment and storage medium in the process of converter tapping" and "A method for quantitatively judging the slag overflow at the furnace mouth in the process of converter tapping" are both useful for the control method of slag overflow in the process of converter tapping As mentioned, the core of the two methods is to use monitoring equipment to monitor the slag. If there is slag overflow, the converter drive equipment is controlled to adjust the tilting curve of the converter, that is, the converter mouth is driven upwards to reduce the amount of slag overflow during tapping. Both methods are based on the premise of converter slag dumping, and are passive remedial measures after slag overflow occurs. The disadvantage is that although the slag does not overflow at the furnace mouth, it increases the possibility of the slag flowing into the ladle from the tapping hole together with the molten steel. The probability of accidents increases, and slag overflow cannot be fundamentally prevented and controlled

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