JPH046870B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a molten metal slag removal method in which slag on a molten metal is removed by suction using a suction head.

Conventionally, in the above molten metal slag removal method, slag is sucked together with air from a suction head suction port placed close to the molten metal slag, and cooling water is jetted against the sucked slag flow in the suction head to solidify the slag into particles and remove excess slag. While the cooling water prevents slag from adhering to the inside of the pipes, the solidified slag, cooling water, air, and water vapor generated due to water cooling are sucked and transported in a three-phase mixed state to a separator, and the separator removes the solidified slag. However, since cooling water is jetted out at the suction head during the entire process of slag suction work, if suction transportation problems occur due to excessive suction of slag, etc. There will be no problem if the cooling water supply is automatically stopped and the suction head is automatically evacuated, but in the unlikely event that the emergency stop device and the automatic evacuation device used for these fail at the same time, the cooling water will fall and the water will get caught up in the high-temperature molten metal. If this occurs, it may become a dangerous situation.

In view of the above-mentioned circumstances, it is an object of the present invention to significantly improve the safety of cooling water from falling onto molten metal during slag suction work, while maintaining high slag removal and recovery efficiency through a rational improvement method. In addition, it is possible to reliably avoid adhesion of suction slag inside the pipe.

A characteristic feature of the method of the present invention is that a suction head suction port is located in the slag above the molten metal, and the slag from the suction head suction port is air-transported to a water cooling section located on the side of a separator that separates cooling water and solidified slag from gas. Alternatively, the remaining slag may be transported under static pressure, and after air begins to be sucked from the suction head suction port due to the lowering of the slag surface, cooling water is flowed from the suction head to the water cooling section to solidify the remaining slag and transport it by suction to the separator. ,
Its actions and effects are as follows.

In other words, the suction slag is not solidified by water cooling in the suction head, but is transported in its liquid state to the separator, and cooling water is supplied to the liquid slag near or within the separator to solidify the slag into particles. As a result, the amount of slag suction can be maintained at the same level as before, and the separator can function for granular solidified slag and cooling water as before, improving slag removal and recovery. Needless to say, it is possible to maintain the same high level as before, and it has become possible to almost completely prevent cooling water from accidentally entering the molten metal during slag suction work.

Moreover, after air begins to be sucked from the suction head suction port due to the lowering of the slag surface, cooling water is flowed from the suction head to the slag water cooling section to solidify the remaining slag in the pipe into particles, which are then sucked and transported to the separator. As a result, it is possible to prevent residual slag from solidifying and adhering to the inside of the pipe without compromising the ability to prevent the cooling water from falling onto the molten metal during the slag suction work described above, and it is possible to maintain high slag suction and transport performance. As a whole,
The safety of slag removal work can be greatly improved while maintaining high molten metal slag removal efficiency.

Next, embodiments of the present invention will be described in detail based on illustrative drawings.

As shown in Fig. 1, the suction head suction port 2a communicating with the suction device 1 is located in the slag S floating on the molten metal L in the ladle 3 or the torpedo car, and the slag S is suctioned and removed from the suction head suction port 2a. At the same time, the suctioned slag S is suctioned and transported to the separator 5 via the suction pipe 4.

A cooling section 6 provided at the inlet of the separator 5
, the cooling water W is jetted against the transported slag S to solidify the slag S into particles, and the solidified slag S separated from the gas G by the separator 5 and water are collected in the water tank 7, and Precipitated solidified slag S by the conveyor 8 installed in the water tank 7
The purpose is to transport and collect the waste.

In addition, numeral 9 in the figure is a condenser for condensing and discharging water vapor generated from the gas G separated by the separator 5 due to the water cooling.

To explain in more detail the slag suction removal procedure by the suction head 2, as shown in FIG. 1 and FIG. The suction head 2 is vertically lowered while supplying air A of approximately the same amount as the suction air volume from the 2a is placed in the molten metal slag S. Thereafter, the flow rate control valve Va installed in the air supply pipe 10 is gradually throttled by the automatic control device 11 to reduce the amount of supplied air, thereby increasing the degree of vacuum in the suction head 2 and the suction pipe 4. The suction of the molten slag S is started gradually and smoothly, and the suction slag S is statically transported toward the separator 5 side, thereby performing the solidification and recovery of the slag as described above.

When suction removal of the slag is almost complete and the slag surface descends until a gap is formed between the suction head suction port 2a and the upper surface of the residual slag S on the molten metal, external air A is sucked into the slag S through the gap.
The vacuum level sensor 12 attached to the front end of the suction pipe 4 detects the decrease in the degree of vacuum in the suction system path due to the suction with the suction pipe 4, and based on the detection result, the cooling water supply pipe connected to the suction head 2 is detected. The on-off valve Vw of 13 is opened and operated by the automatic control device 11, thereby sucking and flowing the supplied cooling water W from the suction head 2 toward the cooling section 6. The flowing cooling water W causes the suction head inlet to flow. The slag S sucked from 2a and the residual slag S remaining in the suction pipe 4 during the above-mentioned static pressure transportation process are solidified into particles, and the solidified slag S is sucked and transported to the separator 5 to carry out the slag removal and recovery work. It will be completed.

In other words, by eliminating the supply of cooling water to the suction head 2 during most of the slag suction removal process, the risk of cooling water accidentally falling from the suction head inlet 2a onto the molten metal L is avoided, improving safety. In addition, by flowing the cooling water W from the suction head 2 toward the separator 5 only after air starts to be sucked from the suction head suction port 2a due to the lowering of the slag surface, the residual slag S can be prevented from flowing into the suction pipe 4. This prevents solidification and adhesion and maintains good transportability of the suction tube 4.

In addition, when positioning the suction head inlet 2a within the molten metal slag S, the suction head inlet 2a is placed in close proximity to the interface between the molten metal L and the slag S with high accuracy within a range where the molten metal L will not be sucked in from now on. In this case, the second
Since the molten metal slag S can be almost completely suctioned and removed by slag suction in the static pressure transport state shown in the figure, cooling water is supplied to the suction head 2 in the final stage of the work after the suction head 2 is evacuated from above the molten metal L. As a result, it is possible to reliably prevent the cooling water from accidentally falling onto the molten metal in all the work steps, thereby further improving safety.

Further, the operation of supplying cooling water to the suction head 2 may be performed manually instead of being performed automatically based on the degree of vacuum detection as described above.

Furthermore, instead of transporting the suction slag S to the separator 5 side by completely static transport, pneumatic transport may be performed by maintaining an appropriate amount of air supplied to the suction head 2.

[Brief explanation of drawings]

The drawings show an embodiment of the molten metal slag removal method according to the present invention, FIG. 1 is a schematic system diagram of a molten metal slag removal apparatus, and FIG. 2 A, B, and C are diagrams showing the slag suction procedure, respectively. 2... Suction head, 2a... Suction head inlet, 5... Separator, 6... Water cooling section, L... Molten metal, S... Slag, W... Cooling water.

Claims (1)

[Claims] 1 A suction head inlet 2a is located in the slag S above the molten metal L, and the slag S from the suction head inlet 2a is air-transported to the water cooling section 6 located on the side of the separator 5 that separates the cooling water and solidified slag from the gas. Alternatively, the slag is transported under static pressure, and after air begins to be sucked from the suction head suction port 2a due to the lowering of the slag surface, cooling water W is flowed from the suction head 2 to the water cooling section 6 to solidify the remaining slag S and transfer it to the separator 5. A method for removing molten metal slag by suction transport.