JPH0480514A - Base metal taking device for arc furnace for melting process - Google Patents

Abstract

PURPOSE:To enable melted base metal to be taken out of a furnace without inclining the furnace by a method wherein a base end of a suction duct removably inserted into an inspection port at a side wall of an arc furnace and immersed into melted base metal accumulated at a bottom pat of the arc furnace is connected to a suction port formed at a ladle to which an air-sealed lid is installed and a vacuum pump for use in discharging the inside air of the ladle is connected to the ladle. CONSTITUTION:A suction duct 9 having an opening or closing valve 10 is inserted from an inspection port 7 into a furnace body 2 by a crane or the like and then an extreme end 9a of the suction duct 9 is immersed into melted base metal 3. Then, a ladle 11 having an air-sealed lid 13 is mounted on a boggie 12 and carried to a forward position of an inspection port 7, a suction port 14 is connected to an outlet port of an opening or closing valve 10, and a discharging port 15 is connected to an end part 17a of a discharging of a discharging pipe 17, respectively. The opening or closing valve 10 is closed, a vacuum pump 16 is operated, an inside part of ladle 11 is reduced to a predetermined vacuum pressure (for example, 110 Torr) under an operation of the vacuum pump 16, then the opening or closing valve 10 is opened, resulting in that the base metal 3 is sucked by the vacuum pressure flows within the suction duct 9 and then the base metal is taken out of the suction port 14 into the ladle 11.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for taking out base metal at the bottom of the furnace out of the furnace in an arc furnace for melting a material to be treated such as garbage incineration ash.

[Conventional technology]

For the purpose of volume reduction and stabilization of municipal waste incineration ash and sludge incineration ash, a method of melting them using arc heat in an arc furnace has been proposed in Japanese Patent Publication No. 56-91118 and Japanese Patent Publication No. 63.
This method was proposed by the applicant of the present invention in Publication No.-8365 and has been put into practical use.

When implementing these methods, it is common to store molten base metal at the bottom of the furnace as a conductive material to make the arc fly, but this base metal must be removed when repairing the bricks inside the furnace. There is. Conventionally, the only way to remove this was to cool the furnace body and then cut and bloom the solidified base metal to remove it, which was a difficult task that required a great deal of labor and time. It is also possible to discharge the molten base metal by tilting the entire furnace body like a steelmaking arc furnace, but making a large furnace with a structure that can be tilted requires a large amount of equipment cost. This poses a number of problems, including the fact that it requires a large space to install the furnace body, and it is extremely difficult to modify an existing, permanently installed furnace.

[Problem to be solved by the invention]

This invention solves the above-mentioned conventional problems, and allows the molten base metal to be taken out of the furnace using a simple and inexpensive device without tilting the furnace body, allowing the modification of existing arc furnaces. It is an object of the present invention to provide a base metal extraction device for an arc furnace for melting processing that is easy to use.

[Means to solve the problem]

However, the base metal extraction device for an arc furnace for melting processing of the present invention has a suction duct that can be inserted into and removed from an inspection hole in the furnace side wall of the arc furnace, and whose tip is immersed in the molten base metal accumulated at the bottom of the furnace. The base end of the ladle is connected to a suction port provided in a ladle covered with an airtight lid, and a vacuum pump for evacuation of the ladle is connected to the ladle.

[Effect]

In the base metal extraction system according to the present invention, if the interior of the ladle is evacuated by a vacuum pump to create a vacuum, the molten base metal at the bottom of the arc furnace is passed through the suction duct into the ladle due to the vacuum pressure. It is sucked into the furnace and discharged outside the furnace.

If an on-off valve is connected to the M end or middle part of the suction duct, the ladle can be evacuated with the on-off valve closed, and high-temperature gas can be prevented from flowing into the vacuum pump.

〔Example〕

An embodiment of the present invention will be explained below with reference to FIG.

In the figure, reference numeral 1 denotes an arc furnace for sludge incineration ash melting treatment, in which a base metal 3 is housed in the bottom 2a of a furnace body 2 fixed on the foundation, and an electrode 5 and base metal 3 are inserted through the furnace lid 4. An arc is generated during this process, and sludge incineration ash (not shown) is melted using the arc heat. Reference numeral 6 indicates the upper surface of the slag produced by this melting process, and the slag is taken out of the furnace from an outlet (not shown). Reference numeral 7 denotes an inspection port provided in the side wall 8I12b, which is closed by an inspection door 8 during operation. Reference numeral 9 denotes a suction duct, which is made by covering the inner and outer surfaces of a heat-resistant steel pipe with a refractory stamp material.A part of the suction duct is inserted into the furnace body 2 from the inspection lower, and the tip fii part 9a is drawn into the molten base metal 3. It is designed to be immersed in water. An on-off valve 10 is connected to the base end 9b of the suction duct 9. This on-off valve 10 is of the same type as a sliding nozzle that is used, for example, by being attached to the bottom of a ladle for pouring during ingot making, and the molten metal contact portion is made of or covered with a refractory material.

On the other hand, reference numeral 11 denotes a ladle placed on a trolley 12, which is equipped with an airtight lid 13 that is airtightly mounted, and a suction port 14 provided on the side wall portion 11a can be attached to and detached from the outlet portion of the on-off valve 10. It is now connected to. An end 17a of an exhaust pipe 17 leading to a vacuum pump 16 is detachably connected to an exhaust port 15 provided in the airtight lid 13, and a cyclone-type exhaust pipe for removing exhaust gas is installed in the middle of the exhaust pipe 17. Dust collector 1
8 are connected. Furthermore, the structure is such that a water cooling device 19 for cooling exhaust gas can be attached.

Next, a method for removing base metal from the arc furnace 1 after melting using the apparatus having the above configuration will be explained.

First, the suction duct 9 with the on-off valve 10 is inserted into the furnace body 2 from the inspection lower part using a crane or the like (not shown), and the tip end 9a is immersed in the molten base metal 3. Next, the take-out WA 11 covered with the airtight lid 13 is placed on the trolley 12 and carried to the front position of the inspection lower, and the suction port 14 is connected to the outlet of the on-off valve 10 and the exhaust port 15 is connected to the end 17a of the exhaust pipe 17. , connect respectively. Then, the on-off valve 10 is closed, and the vacuum pump 16 is operated to maintain a predetermined vacuum pressure (for example, 110T) inside the valve 11.
orr). When the on-off valve 10 is opened, the base metal 3 is suctioned by vacuum pressure, flows through the suction duct 9, and is taken out from the suction port 14 into the ladle 11. During this extraction, operate the vacuum pump 16 as necessary to remove the water.
A depressurization operation within A11 may be added. When a predetermined amount of base metal 3 is taken out into the ladle 11, this airtight lid 13 is removed.
Ladle with lid] 1 is removed from the on-off valve 10 and exhaust pipe 17, and if there is any remaining amount of base metal 3 in the furnace body 2, use another new ladle 11 with an airtight lid 13 and remove the base in the same manner as above. All you have to do is take out the metal 3. If the base metal is removed using a plurality of ladles 11 in this manner, the ladles 11 may be small, and there is an advantage that the ladle containing the base metal is also small in weight and easy to handle.

After reducing the pressure inside the ladle 11 to 110 Orr using the illustrated device (inner diameter of the suction duct 9 = 200 mm, total length = 1500 sm+, level difference H between the end 9a and the center of the horizontal part of the duct = 900 jWI). When the closing valve 10 was opened, 0.5 m3 of the base metal 3 made of molten steel could be taken out into the ladle 11 in about 1 minute.

The present invention is not limited to the above-described embodiment; for example, the airtight lid 13 may remain connected to the exhaust pipe 17 at all times,
The airtight lid 13 may be attached to and detached from the ladle 11 that has been transported. Further, the on-off valve 10 may be of a barrel type, or may be provided in the middle of the suction duct 9. Further, in the above embodiment, the base end 9b of the suction duct 9 is connected to the suction port 14 via the on-off valve 10, but the base end 9b is directly connected to the suction port 14 without using the on-off valve 10. Good too. Note that if the on-off valve 10 is not used, it is not possible to create a vacuum in the ladle 11 in advance, so the base metal 3 must be drawn out by suction while operating the vacuum pump 16.

Further, the present invention can be used as a base metal extraction device for an arc furnace that performs melting treatment of materials to be treated other than waste incineration ash.

〔Effect of the invention〕

As explained above, according to the present invention, molten base metal can be sucked out into a ladle using a simple and inexpensive device without tilting the furnace body, and it is possible to use an existing fixed-body arc furnace. It is also easy to modify and attach the base metal extraction device of the present invention.

[Brief explanation of the drawing]

FIG. 1 is an equipment layout diagram of a base metal extraction device showing an embodiment of the present invention. 1... Arc furnace, 2... Furnace body, 2a... Furnace bottom,
2b...Side wall part, 3...Base metal, 7...Inspection port, 9...Suction duct, 9a...Tip part, 9b...
... Base end part, 10 ... Opening/closing valve, 11 ... Ladle, 13
... Airtight lid, 14... Suction port, 15... Exhaust port,
16...Vacuum pump, 17...Exhaust pipe.

Claims (1)

[Scope of Claims] 1. The base end of the suction duct, which can be inserted into and removed from the inspection opening in the side wall of the arc furnace and whose tip is immersed in the molten base metal accumulated at the bottom of the furnace, is covered with an airtight lid. A base metal extraction device for an arc furnace for melting processing, characterized in that the device is connected to a suction port provided in a ladle on which the metal is deposited, and a vacuum pump for exhausting the inside of the ladle is connected to the ladle. 2. The base metal extraction device for a melting arc furnace according to claim 1, further comprising an on-off valve connected to the base end or intermediate portion of the suction duct.