JPS60210764A - Apparatus for sampling molten substance in shaft furnace - Google Patents

Abstract

PURPOSE:To certainly sample the molten substance at the desired accurate position in the vicinity of the tuyere in a shaft furnace, by adhering the molten substance to the sampling instrument provided to the leading end part of the freely advancing and retracting sampling bar in a sonde. CONSTITUTION:To the sonde 2 for searching the interior of a shaft furnace, a sampling bar 11 freely advancing and retracting along the long axis direction of the sonde 2 is provided. A cooling cylinder 12 cooled by water for forming a sampling instrument is mounted to the leading end part of said bar 11 and the molten substance 16 in the shaft furnace is adhered to the cooling cylinder 2. By this constitution, the molten substance in the shaft furnace at the desired accurate position in the vicinity of the tuyere in the shaft furnace can be sampled.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a molten material sampling device in a metallurgical furnace such as a blast furnace or a smelting reduction furnace.

In the blast furnace, the ore is melted almost at the bottom of the shaft, and the molten material flows down to the hearth through a packed bed of coke. While flowing down the coke packed bed, this melt reacts with coke and slag, causing important reactions that determine the quality of the hot metal, such as reduction of FeO remaining in the melt slag, carburization of the hot metal, silica, vulcanization, or desulfurization reaction. The reaction progresses. However, what daily operators only know is the quality of the hot metal when it is finally tapped from the hearth.
For example, when obtaining hot metal with high sulfur content and poor quality, it was unclear in which region the abnormal condition was occurring. This is because they did not have the means to sample the melt in commercial blast furnaces. Regarding a slightly smaller test blast furnace, there is an example reported by the Institute of Industrial Science, the University of Tokyo (r. Iron and Steel J.
1976, No. 5, pp. 483-494 ("Changes in state in high-temperature region due to changes in heat level"), there are devices that sample both solid and liquid at the same time, but in practical commercial blast furnaces, the loading conditions of coke in the furnace and Due to the different heat load conditions, this device could not be applied to sampling the melt of commercial blast furnaces as it was.

Apparatuses for sampling solids in commercial blast furnaces include Japanese Patent Publication No. 47259/1983 and Japanese Patent Publication No. 16188/1983.

Japanese Patent Publication No. 47-47259 uses a water-cooled device similar to the above-mentioned report, but this device has severe thermal conditions in the area where the molten material flows down inside the blast furnace.
There are problems such as bending and deformation of the sonde body, and the inability to rotate the sampling port due to adhesion and solidification of melt between the sampling port and the inner circumferential tube wall of the sonde, making it unsuitable for sampling melted materials.

In addition, in the example described in Japanese Patent Publication No. 50-16188, a rod-shaped body with a ladle at the tip is provided inside a cooling cylindrical tube so as to be able to move forward and backward, and this is an application example in which a solid sample can be sampled. It is shown as follows. In this case, bending and deformation of the sonde body can be avoided by strengthening the cooling of the outer cylinder, but (1) There is a problem with the heat resistance of the ladle when inserting it into the coke packed bed to sample the melt. , (2) Coke etc. gets caught between the ladle and the sonde, making it impossible to store the ladle inside the sonde after sampling, making the melt sampling position unclear; (3) Coke-filled bed Because the load is applied to the ladle inside,
It is necessary to increase the thickness of the ladle, which makes the ladle part larger and the sonde body itself thicker, which has the disadvantage of increasing the driving force of the sonde, and there are many problems when using it for molten material sampling. .

The present invention eliminates the above-mentioned drawbacks and provides a sonde body that (a) can clearly define the sampling position of the molten material in the blast furnace, (b) can withstand the load in the coke layer, and (c) has a small diameter sonde body. The purpose of the present invention is to provide a melt sampling device that can be accommodated in a.

The present invention is based on (a) the long-standing experience of adhering slag to the slag winding rod of an iron rod and observing the color, viscosity, etc. of the slag; (b) (C) In the region where the molten material flows down in the blast furnace, the hold-up of the molten material increases in the region filled with fine particles, and the melting Experimental results show that objects are less likely to flow down.

Based on the above, a device for sampling molten material inside a blast furnace was developed.

FIG. 1 shows an overall view of an apparatus for sampling molten material in an operating vertical furnace. The sonde body 2 is inserted into a coke packed bed l in a vertical furnace that is in operation. The gas seal for the high pressure inside the furnace is provided by gland packing 4 when the sonde is inserted, and by 2 when the sonde is pulled out.
It is sealed by a ball valve 3. A truck 6 for moving the entire sonde is attached to the rear end of the sonde, and the truck 6 is driven back and forth by hydraulic pressure or a chain.

A hydraulic or electric cylinder 7 is mounted on the truck 6 to drive the sampling parser 2 back and forth for sampling the melt in the sonde. Further, in order to prevent deformation of the sonde and prevent excessive force from being applied to the gas seal system 3.4 or the tuyere connection pipe, the sonde body is supported by guide rollers 5. In addition, in order to prevent deformation of the sonde and to completely seal the furnace internal pressure, the sonde body has a triple tube structure and a refrigerant is passed through the interior 9 for cooling.

FIG. 2 shows a detailed view of the sampling section of the embodiment of the present invention. A sampling par 11 is inserted into the sonde 2 so as to be freely forward and backward in the axial direction of the sonde. The sampling par 11 has a cooling cylinder 1 at its tip, which has a smaller diameter than the sampling par.
It is equipped with 2.

This cooling tube 12 is a sampling device according to an embodiment of the present invention, and has a shape that allows melted matter to adhere to the outer surface of the cooling tube in the form of a thin film, while making it difficult for large lumps to adhere to the cooling tube. It is unique in that it is a device that allows storage to be done without getting in the way.

The outer diameter of the sonde 2 is preferably as small as possible without buckling in order to reduce the driving force required to move the sonde forward and backward into the furnace. In order to secure the required amount of cooling medium, it is necessary to make the cross section larger than a certain size in relation to the original pressure of the cooling medium.

In addition, a space 13 is provided between the cooling cylinder 12 and the inner surface of the sonde body 2 in order to generate a solidified layer of molten material on the outer surface of the cooling cylinder 12 with a thickness proportional to the cooling capacity of the cooling cylinder 12. There is a need. The space 13 is created by making the outer diameter of the cooling cylinder 12 smaller than the outer diameter of the sampling par 11, or by making the outer diameters of the cooling cylinder 12 and sampling par 11 the same, and by increasing the diameter of the sonde inner pipe in the cooling cylinder 12 housing part. It is better to choose one of the following.

As shown in FIG. 2, the gap between the sonde and the sampling device is set to the minimum size that allows the sampling device to move. Sampling par 1 at the rear end of sonde 2
The pressure inside the furnace is sealed by a seal 10 between the probe 1 and the sonde. . The inside of the sampling par 11 constitutes a cooling medium flow path, and also serves as a water supply and drainage passage to the tip cooling cylinder 12.

Next, regarding the material of the cooling tube 12, the wettability between the outer surface of the cooling tube 12 and the molten material is a problem.For example, in the case of hot metal, it is preferable that the cooling tube 12 is made of steel rather than copper; It is effective to apply an oxide-based surface coating to the surface. Therefore, in order to efficiently sample both hot metal and slag at the same time, it is preferable to apply an oxide coating to a portion of the outer surface of the cooling cylinder 12.

The length of the cooling cylinder is closely related to the flow pattern of the melt. In other words, in a coke-packed bed like in a blast furnace, the melt flows along the surface of the coke particles, and the flow path does not wet the entire coke surface; The molten material flows down through it. When the flow rate of the melt is increased or decreased, the number of streak-like routes increases or decreases. In order to efficiently sample such a melt flow, the length of the cooling cylinder preferably satisfies the following requirements. Third
The figure shows coke particles 1 around the cooling cylinder 12 when the cooling cylinder 12 is further protruded into the furnace from the sonde 2 inserted into the furnace.
5 schematically shows the existence forms of melt 16 and melt 16. When the length of the cooling cylinder 12 is less than or equal to the radius of the existing coke particles 15, the chance of the cooling cylinder 12 coming into contact with the melt 16 decreases rapidly. Furthermore, when the flow rate of the melt 16 is small, the longer the length of the cooling cylinder 12, the greater the chance of contact with the melt 16, which is preferable. The optimum length of the cooling cylinder 12 must be within the range that the cooling capacity of the cooling cylinder 12 can absorb. The bending strength of the cooling cylinder 12 becomes long enough to withstand the bending moment due to the coke layer load.

Next, FIG. 4 shows a detailed diagram of a sampling device according to another embodiment of the present invention. In this example, the porous body 22 is removably attached to the tip of the sampling device using a screw-type joint 23. This is because, as will be described later, the molten material collected inside the porous body is collected together with the porous body, and after the porous body is crushed, the metal and slag are separated and recovered. Therefore, it is necessary to have a structure in which the porous body can be attached and detached each time a measurement is made. Further, it is better to provide some space between the porous body and the inner tube of the sonde so that fine particles attached to the porous body do not get caught when the porous body is drawn into the sonde after collecting the melt.

Next, we will discuss the structure of the porous body and the function of collecting the melt.

When the melt flows down by gravity through a space filled with granules, a certain amount of the melt is trapped in the voids of the granules even after the melt has finished flowing down, as given by the following equation, for example. The captured melt volume at this time is called the static hold up (H) of the melt.

Here, σ: Surface tension of melt DP dinuclear particle Diameter: density of melt φ: Particle shape factor (kl) θ: Contact angle between particulate matter and melt ε: Porosity of granular packed bed (1) g: Gravity conversion factor However, the applicable range of the above formula is O<H<ε.

For example, from the above equation, in order to increase the static hold up H, the particle diameter DP should be made smaller, the porosity ε should be made smaller,
It turns out that it is effective to reduce the contact angle between the melt and the granular material. In particular, the effect of particle size is significant.

Therefore, if a porous body is made by adhering granules of appropriate particle size and material, and this is inserted into a packed bed where melt flows down, the melt will accumulate inside the porous body, which corresponds to a static hold-up. The melt can be sampled.

If the material is ceramic or high-melting point metal, such a porous body can be easily manufactured by filling particles in a crucible and sintering them, or if the material is carbon-based, it can be manufactured by applying an organic adhesive. It can be easily obtained by filling the particles with the particles and then raising the temperature. Figure 6 shows an example of the carbon-based porous body produced in this way. In this example, the porous body is cut into a cylindrical shape after molding, the unevenness of the cylindrical surface is reduced, and the coke is heated in the coke-filled bed. I tried to avoid getting involved. Further, the joint portion 23 was bonded with a carbon screw prepared in advance.

The sampling procedure in an actual reactor is as follows.

First, set the sampling bar inside the sonde. At this time, it is convenient to fit a backing plate 14 having a diameter equal to the inner diameter of the ship onto the tip of the sampling bar.

The reason is that it is possible to prevent dust and coke powder from entering the space 13 before sampling the melt. Next, adjust the seals 4 and 10, make sure that the seals are complete, and close the valve 3. Open it, move the trolley, insert the sonde to a predetermined position, and stop. Next, drive the cylinder 7 and push the sampling bar 11 into the furnace together with the backing plate 14. After leaving it for a predetermined time, move the cylinder 7 and insert the sampling bar. , then move the sonde back and close valve 3.

Finally, the sonde is pulled out from the gas seal systems 3 and 4, and if a cooling cylinder is used as a sampling device, the attached solidified material is scraped off with a spatula or the like, and the metal and slag are separated and recovered.

When a porous body is used as a sampling device, the porous body is removed from the sampling bar, and then the porous body is crushed with a crusher to separate and recover metal and slag.

Example (I) A triple-pipe water-cooled sonde with a regular steel pipe with an outer diameter of 78 mm as the outermost pipe was manufactured, a sampling bar made of a regular steel pipe with an outer diameter of 22 mm was built in, and a sampling bar with an outer diameter of 14 mm was installed at the tip of the sampling bar.
A cooling cylinder made of ordinary steel pipe was installed, an internal cooling water channel was constructed integrally between the sampling bar and the cooling cylinder, and a partition plate was provided at the center of the tube to divide the tube cross section into two. The length of the cooling cylinder is 100
mm, and was cooled with 0.45 t/l of water.The sonde body was cooled with 20 t/h of water.The sonde had an internal volume of 2
While the 800m" blast furnace was in operation, the air blast was stopped, and the sampling bar was inserted up to 1.5m toward the center of the furnace. Push the sampling bar further by 105mm and hold for 40 seconds to return the sampling bar to its original position. It was pulled out. In this way, the melt inside the blast furnace could be sampled. The recovered thin film metal and slag were approximately 8 grams and 1.5 grams, respectively.

Example (II) A triple-tube water-cooled sonde similar to Example (I) was manufactured, and a sampling bar made of ordinary steel pipe with an outer diameter of 22 mm was built in. Carbon-based particles with a particle size of 5 to 10 mm were attached to the tip of the sampling bar. A porous body with an outer diameter of 20 m, to which granules were adhered, was joined by screwing. The length of the porous body was 80 mm. This sonde was installed in a blast furnace with an internal volume of 2800 m'', and while the blast furnace was in operation, it was inserted up to 2 m in the direction of the center of the furnace through the tuyere, where the air supply was stopped, and the sampling bar was further pushed in by 85 mm, held for 1 minute, and then the sampling bar was inserted. The probe was pulled back and the sonde was pulled out of the furnace.The porous body was collected and crushed, and the sampled metal and slag were collected.The weights of the metal and slag were 4.5 grams and 5 grams, respectively.

Since the apparatus for sampling the molten material in the blast furnace of the present invention is configured as described above, it is possible to sample the molten material in the blast furnace without using a ladle or the like. The sampling device, which consists of a cylindrical body with small grooves, etc., is housed inside a small-diameter sonde, so it is easy to handle and there is no problem with strength, and unlike dish-shaped instruments, there is no risk of large lumps getting stuck and making it impossible to store. In addition, the melt can be sampled from a desired and accurate location near the siding in the blast furnace.

Therefore, it is possible to clarify the reaction and other conditions in the melting zone region of the blast furnace.

[Brief explanation of drawings]

Fig. 1 is an overall configuration diagram of a sonde constituting a sampling device according to an embodiment of the present invention, Fig. 2 is a detailed vertical cross-sectional view of the melt sampling device, and Fig. 3 is a schematic explanatory diagram of the melt flow in the furnace. , FIG. 4 is a detailed longitudinal sectional view of another embodiment of the melt sampling device of the present invention, and FIG. 5 is a perspective view of the porous body. 1... Coke filled bed 2... Sonde 3... Ball valve 4... Gland packing 5... Guide roller 6... Cart 7... Cylinder 8... Guide frame 9... Inside 10... Seal member 11... Sampling bar 12... Cooling cylinder 13... Space\ 14... Backing plate 15... Coke particles 16...
Molten material 22..., porous body 23...Joint part Applicant Kawasaki Steel Co., Ltd. Agent Patent attorney Yoshi Kosugi Male patent attorney *S Kazunori Ward Figure 5

Claims (1)

[Claims] l A sampling bar that can move forward and backward in the long axis direction of the sonde is provided in the main body of the sonde for exploring the inside of the blast furnace, and the tip of the sampling bar is equipped with a sampling device that attaches the molten material inside the blast furnace. Blast furnace in-furnace melt sampling device.