CN-122012852-A - Method for reducing tapping hole slag discharging in tapping process of converter

Abstract

The invention discloses a method for reducing tapping hole slag discharging in the tapping process of a converter, and belongs to the technical field of metallurgy. According to the invention, aiming at the problems that molten steel vortex slag is rolled up in the later stage of the tapping process of a converter and slag from a tapping end point of the tapping hole falls into a ladle, water flow is intermittently sprayed from the outside of the converter to the outlet of the tapping hole before molten steel vortex slag begins to appear and water flow is continuously sprayed at the moment when molten steel is completely discharged and slag begins to intensively and gush out, the water vapor generated by flash evaporation and the burst kinetic energy thereof are utilized to 1) weaken the vortex strength of the molten steel surface in the converter by intermittently breaking the state of the molten steel in the tapping hole in the tapping process so as to reduce vortex slag and 2) reversely drive the slag flowing into the tapping hole from the inside of the converter at the tapping end point and continuously prevent the slag in the converter from flowing into the tapping hole again, so that the same set of water jet system device can more conveniently, economically and effectively inhibit the total amount of slag from the tapping process and the tapping end point.

Inventors

• WU LIPING
• ZHENG HONG
• WU TIANYU

Assignees

• 马鞍山乌力平冶金技术工作室

Dates

Publication Date

20260512

Application Date

20260306

Claims (4)

1. 1. A method for reducing tapping hole slag in tapping process of converter is characterized by that 1) before the molten steel vortex in the furnace is wrapped up in slag above the tapping hole, water flow is intermittently sprayed from outside the furnace into the tapping hole outlet, the state of molten steel flow in the tapping hole is periodically destroyed by utilizing water vapor generated by flash evaporation after water is heated and its explosion kinetic energy, the generation of strong vortex of molten steel liquid surface above the tapping hole is intermittently disturbed, and the slag is continuously inhibited from being involved in the tapping hole, and/or 2) at the moment that the molten steel is completely discharged from tapping end point, water flow is continuously sprayed into the tapping hole outlet from outside the furnace, and the water vapor generated by flash evaporation and its explosion kinetic energy are reversely driven back to the slag which has been poured into the tapping hole from the furnace and continuously prevented from flowing into the tapping hole again.
2. 2. The method for reducing tapping hole slag discharging during tapping of a converter as set forth in claim 1, wherein the water jet injected into the tapping hole outlet is a water jet penetrating through the tapping hole to flow out of the melt and enter the tapping hole, and an acute angle formed by the central axis of the water jet and the central axis of the tapping hole is 25-65 degrees.
3. 3. The method for reducing tapping hole slag discharging in the tapping process of a converter according to claim 1, wherein the system device for injecting water flow is composed of 1) a single-channel/double-channel water jet spray gun mechanism, 2) a spray nozzle arranged at the front end of the spray gun, 3) a water jet conveying pipeline and valve group, 4) a converter tapping tilting angle detector for controlling the start and stop of intermittent spraying, 5) a tapping steel flow slag entrainment detector for controlling the start of intermittent/continuous spraying, and 6) a water flow injection controller.
4. 4. A method for reducing tap hole slag discharging during tapping of a converter as set forth in claim 3, wherein said water jet lance mechanism is mounted on the body of the converter in the form of a fixed or fixed base telescopic/rotary/oscillating type, and said spray head is a liquid column flow spray head.

Description

Method for reducing tapping hole slag discharging in tapping process of converter Technical Field The invention relates to the technical field of metallurgy, in particular to a method for inhibiting a large amount of slag from rushing out of a tapping hole at the tapping end point of a converter. Background The converter steelmaking process is a ferrite purification process for slagging or gasifying impurities in molten iron in a strong oxidizing atmosphere, slag after blowing is enriched with various harmful compounds, and any slag entering a ladle along with molten steel during tapping can pollute the molten steel and can have various negative effects on the subsequent molten steel deoxidizing and refining processes. The method for throwing refractory material inverted cone/inverted cone slag stopping device in the prior art can inhibit the slag from entering the ladle to a certain extent, but cannot reduce the slag in the later stage of tapping, the inhibiting effect on the slag after vortex rolling of the molten steel in the middle and later stages of tapping is not ideal, and the combined method for throwing refractory material inverted cone/inverted cone slag stopping device in the prior art can well inhibit the slag from entering the ladle, but has a plurality of specific defects and defects of the method. The technical method of the slag stopping device for throwing refractory materials of inverted cone/inverted cone is that the quasi-density of the device is designed to be between molten steel and slag, a guide rod of the device is inserted into a steel outlet after the device is thrown into the furnace in the middle and later stages of tapping, the inverted cone/inverted cone which specifically bears the slag stopping function is always positioned between the interface of the molten steel and the slag, the slag rolling of the vortex of the molten steel can be restrained to a certain extent only when the inverted cone/inverted cone approaches the inlet of the steel outlet in the later stages of tapping, the slag rolling can be prevented to a certain extent, the slag can fall into the steel outlet to stop the slag from falling into a steel ladle only when the molten steel is about to be completely discharged, in principle, the moment of the slag stopping effect after the slag stopping effect is passive, the approximately smooth refractory materials of inverted cone/inverted cone which only has a plurality of shallow grooves on the side surfaces between the molten steel slag can not avoid the vortex of the molten steel, the vortex core which can not enter the molten steel to interfere the slag, the slag can not be wrapped up when the molten steel outlet is irregular, the slag can not be well blocked off the slag at the end point of tapping, and the slag can be controlled by adopting the pneumatic slag stopping method or the combined slag stopping method which can only control the slag stopping slag after the slag. The pneumatic slag blocking method is a technology developed in the last 80 th century for solving the problem of slag gushing after the tapping end point of a converter, and has the core principle of pneumatic interference and momentum transfer, namely, high-pressure gas is reversely sprayed into the outlet area of a tapping hole through a closely aligned spray nozzle when molten steel is completely discharged at the tapping end point, the slag and molten steel in the tapping hole are forced back by utilizing the airflow momentum, the slag is prevented from directly falling from the tapping hole, an air curtain or an air column is formed above the tapping hole in the furnace, and the slag is prevented from falling back into the tapping hole again to enter a ladle. Although the method has higher success rate of slag blocking of the rear slag, the method has a plurality of fatal defects, and mainly comprises 1) because the adopted high-pressure gas is much smaller than the density of slag, a large-diameter single-hole or multi-hole combined nozzle capable of blowing sufficient gas needs to be aligned closely with the outlet of a steel tapping hole from bottom to top to flow to the direction of the steel slag to blow nitrogen (in order to obtain better effect, even the front end of the nozzle needs to enter or at least be flush with the plane of the outlet of the steel tapping hole), the combined nozzle is easy to be blocked by local or partial spray holes of the combined nozzle and/or slag blocking, thereby influencing the success rate and the operation rate of slag blocking; 2) when the lower mouth of the steel tapping hole is severely reamed or irregular due to steel slag erosion and/or mechanical damage, the air flow is difficult to completely block slag, and part of slag still enters the ladle, 3) the slag and/or the steel slag at the nozzle which is not cleaned in time often impacts and damages the refractory bricks at the outlet of the steel tapping hole when the nozzle moves to the ou