JPS632431Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a molten material sampling device having a temperature measuring function, which is used in a vertical furnace such as a blast furnace or a smelting reduction furnace.

[Conventional technology]

The movement of the molten material in the molten zone in front of the tuyeres of metallurgical furnaces such as blast furnaces and smelting reduction furnaces has long been used to clarify phenomena such as melting of the tuyere and slag return to the tuyere. It was something I wanted to do.

In recent years, rapid control of hot metal components has been required in blast furnaces, and technology has been developed to inject iron ore and pulverized coal through the tuyeres. Because the hot metal composition changes due to the reaction between the powder and the dripping hot metal near the tuyere, clarifying the reaction mechanism and speed will lead to accurate control of the hot metal composition. In order to clarify the changes in the components of the dripping hot metal and the temperature during the reaction due to powder injection, it is necessary to simultaneously sample the molten metal in the operating furnace and measure the temperature.

The area in front of the tuyere is hot,
Due to the fact that the coke layer is filled and a large heat load condition occurs locally due to the flow of hot metal, etc., a sonde is inserted during the operation of the furnace.
Investigating the inside of a reactor is extremely difficult.

Regarding equipment for gas and sampling and/or temperature measurement in operating blast furnaces,
There is an apparatus disclosed in No. 50-16188. This device is primarily used to collect ore samples from blast furnace shafts and the like. In order to collect molten material in high-temperature areas such as the tuyere or molten zone, the heat resistance of the sampling container, the adhesion of molten metal to the container, or the insertion of molten metal into the boundary between the lance body and the sampling container are important. There are problems such as malfunction of the sampling container due to this, and special measures are required. Furthermore, conventionally, the time required to protrude a sampling container into a furnace to collect a sample of ore is short, and there is no need to take special consideration into heat resistance of such a sampling container.

Tuyere sondes used during wind breaks are also known. Although this device mainly samples the coke in front of the tuyere and measures the temperature at the same time, it cannot be used as a melt sampling device having a temperature measurement function used during the operation of the present invention for the following reasons.

(1) In most cases, the lance itself is not cooled because it is intended to be used during periods of rest. The lance deforms significantly during sampling, making it difficult to use while the furnace is in operation due to gas seal issues.

(2) The lance itself is cylindrical, with the opening oriented in the axial direction. When sampling coke and other furnace contents, it is possible to collect molten material that has gotten into the furnace, but it is not possible to sample with the aim of obtaining a fixed amount of molten material.

(3) Because a thermocouple is used as a temperature measuring device, it is difficult to measure the temperature near the tuyere or in the molten zone for a long period of time. If the length of the thermocouple protruding into the furnace is shortened to increase its durability, the measured value becomes inaccurate due to the influence of the lance body. Even if improvements are made to improve heat resistance, such as using a refractory protective tube, the measured temperature is limited to 1100-1600°C and within the coke layer where slag and molten iron are dripping.

[Problem that the invention attempts to solve]

The present invention improves the shortcomings of the conventional equipment as described above, and makes it possible to sample a predetermined amount of melt near the tuyere or within the melting zone in an operating vertical furnace, and simultaneously measure the temperature. The purpose is to provide equipment.

[Means for solving the problem]

FIG. 1 shows a detailed view of an embodiment of the lance body of the present invention.

A cooling lance 2 for sampling a molten material in a vertical furnace, to which the present invention is applied, has an outer tube 2a, a middle tube 2b, and an inner tube 2c arranged in a triple tube shape.
Cooling channels 22 are provided in the gap between the inner tube 2b and the inner tube 2b, and between the inner tube 2b and the inner tube 2c, so that the lance 2 itself does not melt or deform in the furnace. The present invention provides the following features a, b, c, d and e in such a cooling lance type melt sampling device.
This is a melt sampling device having a measurement function.

(a) An optical fiber protection tube 20 which is disposed from the outer end of the lance 2 to the inner end of the furnace through a cooling water passage 22 and is connected to a gas introduction tube 21 for introducing a purge gas.

(b) Optical fiber 19 for in-furnace temperature measurement housed in optical fiber protection tube 20.

(c) A melt sampling container 13 is housed in the inner tube 2c and is provided so as to be able to protrude in front of the furnace inner end of the lance 2.

(d) Moving means 24 for moving the melt sampling container 13 in the longitudinal direction of the lance 2.

(e) A tip fitted to the inner end of the lance 2 to protect the sampling container 13 and the tip of the optical fiber when the lance is inserted into the furnace, and to be able to fall off when the melt sampling container 13 is protruded into the furnace. Closure.

〔Example〕

FIG. 2 shows an overall view of an apparatus for sampling the molten material in an operating vertical furnace. FIG. 2 shows the lance body 2 inserted into the coke packed bed 1 in the vertical furnace in operation. The gas seal for the high pressure inside the furnace is sealed by a gland packing 4 when the lance is inserted, and by two ball valves 3 when the lance is pulled out. In addition, a cart 6 for moving the entire lance is attached to the rear end of the lance.
is driven back and forth by hydraulics or a chain.

A hydraulic or electric cylinder 7 is mounted on the truck 6 to drive the sampling section back and forth for sampling the melt in the lance. Further, the lance is supported by guide rollers 5 in order to prevent deformation of the lance and to prevent excessive force from being applied to the gas seal systems 3, 4 or the tuyere connection pipe.
Furthermore, in order to prevent deformation of the lance and to completely seal the furnace internal pressure, the lance itself has a triple-tube structure and water is passed inside to cool it.

The temperature measuring section will be explained with reference to FIG.

An optical fiber protection tube 20 is passed through a cooling water channel 22 in the lance 2, and its tip is opened into the furnace. An optical fiber 19 designed to provide an amount of light that allows temperature measurement with a radiation thermometer is installed inside the optical fiber protection tube 20. Further, a purging N ₂ introduction pipe 21 is connected to the optical fiber protection pipe 20 to remove dust from the tip of the optical fiber. In this way, the temperature measuring fiber 19
By installing this in the cooling water channel 22, the purging N ₂ only needs to have a purge function and does not need to have a cooling function. In addition, in conventional temperature measurements using optical fibers, an image fiber is often used in conjunction with observation inside the furnace. For this reason, the diameter of the fiber itself is large, 10 to 15 mmφ, and the opening area in the furnace is inevitably large, for example, 100 ^mm2 , and the _N2 for purging is large.
The amount increases. For this reason, there was a problem in that the charge in front of the fiber was cooled by the N ₂ for purging, making the temperature measurement inaccurate.

In contrast, in the present invention, since a fiber dedicated to temperature measurement is used, the diameter of the fiber itself is 4 to 5 mmφ, and the opening area can be suppressed to several mm ² . As a result, the amount of _N2 used for purging is reduced to about 1/100 of the conventional amount, allowing accurate temperature measurements that are not affected by the cooling of _N2 used for purging.

Furthermore, it is difficult to measure the temperature using a fiber at the same time as melt sampling using the conventional method in which the fiber is installed in the center of the cooling pipe. If the melt sampling device is installed in the center of the cooling pipe,
There was no space to install a fiber, so it was necessary to create two lances that had one function or the other. The present invention can reduce the number of optical fibers to one by providing a thin optical fiber protection tube in the cooling conduit.

In FIG. 1, the optical fiber 19 is drawn below the melt sampling container 13, but in order to avoid the influence of the sampling container 13,
It is desirable to install it diagonally above the sampling container 13 and as far away from the sampling container as possible.

Next, the sampling section will be explained.

The diameter of the lance 2 is preferably as small as possible without buckling in order to reduce the driving force, and the larger the melt sampling container 13 inside the lance 2, the more melt can be collected. For this reason, in the embodiment, the lance 2 has a distal end with an enlarged interior as shown in FIG. 1, and a melt sampling container 13 is housed therein. The melt sampling container 13 is connected via a pipe 10 to a drive handle 18 . By moving the drive handle 18 back and forth, the melt sampling container 13 is moved into and out of the lance and into the furnace.

However, if the ease of designing and manufacturing the lance 2 is more important than the amount of molten material collected, the lance 2
It is also possible to have a structure in which the inner tube is a straight tube and a melt sampling container is stored at the tip thereof.

In a vertical furnace, the amount of molten material dripped into the furnace is several g/
cm ² ·min, about 10-odd g/cm ² ·min. on the other hand,
In order to know the typical composition of the melt in the furnace or to know the rate of dripping, a sample of at least 50-100 g is required. Since the cross-sectional area of the melt sampling container 13 is several tens of cm ² , it is necessary to leave the melt sampling container 13 out of the furnace for about one minute. Since the temperature inside the furnace is as high as 1100 to 1600°C, the melt sampling container 13 is required to withstand this high temperature and not react with the melt (slag, metal). At the same time, it is exposed to sudden high temperatures (1100 to 1600°C), so it is necessary to use a material that is resistant to thermal shock.

As a container that satisfies the above requirements, it is effective to make the melt sampling container 13 from a refractory material. As the material of the refractory, graphite or SiC is preferable from the viewpoint of heat resistance and thermal shock resistance. In addition, if the temperature of the melt sampling container increases due to long exposure in the furnace, and reaction with the melt becomes a problem when graphite or SiC is used, Al ₂ O may be added to the surface of the sampling container 13. ₃ or apply MgO paste.

FIG. 3 shows a detailed view of an embodiment of the sampling container 13. The material of this sampling container 13 is graphite, and an alumina paste 15 is applied thereto to prevent reaction with the melt.

When storing the sampling container 13 in the lance, the contents in the furnace may get caught between the lance and the sampling container storage opening, making it impossible to pull back the sampling container 13. If the material of the container is refractory, the tensile strength is low, so pinching the charge will lead to destruction of the container.Prevent the solid charge from getting caught between the sampling container and the lance. Therefore, the top surface of the sampling container should have a slit shape. In addition, in order to clarify the sampling area, the top surface of the slit is slightly concave, and only the melt is sampled.

However, if the ease of designing and manufacturing the lance 2 is more important than the amount of melt to be sampled, the dimensions of the melt sampling container 3 will be smaller than the coke particle size in the furnace. For this reason, the shape of the melt sampling container 3 in the shape of a normal spoon can sufficiently prevent damage to the container.

A heat insulating packing 14 is placed between the sampling container 13 and the pipe 10 to prevent heat from being transferred to the metal parts.

Further, in this embodiment, the sampling container is fixed with bolts, but it is also possible to provide a screw in the sampling container body and fix it with a screw.

Next, the tip closure tool 9 will be explained.

When inserting the lance 2 into the furnace, a force of several tons to 10 tons is applied to the lance 2. There is also an insert at the tip of the lance,
Since the molten mixture is pressed, when the tip is open, the molten material is inserted into the gap between the lance 2 and the sampling container 13, and the sampling container 13
becomes unable to move forward. Alternatively, problems such as the sampling container 13 made of refractory material breaking occur.

For this reason, in the present invention, when inserting the lance into the furnace, a tip stopper 9 is attached to the lance 2 to protect the sampling container 13. After inserting the lance 2 to a predetermined position, as shown in FIG. 4, the lance 2 is moved back and the container 13 remains in the same position, thereby pushing the tip closure 9 into the furnace and discarding it into the furnace. do. Thereafter, the lance is retracted to the measurement position and the container 13 is placed in the furnace for one to several minutes to sample the melt. After sampling is completed, the container 13 is retracted and stored in the lance again. If necessary, an inert gas can be blown through the purge line 12 to prevent oxidation of the melt in the vessel.

In this embodiment, the case where the molten material sampling container 13 is stored at the tip is shown, but as can be easily understood, the same tip closing tool 9 can be used even when an image fiber is stored in the lance.
And the method of discharging the fuel into the reactor can be applied.

[Effect]

Next, the operation of the melt sampling device of the present invention will be explained with reference to FIGS. 4a, b, and c. Figure 4 shows
Only the lance inserted into the furnace is shown, and position 23 is the sampling position.

(a) When inserting the lance: When the lance 2 moves forward, the tip stopper 9 is attached and the lance moves forward while protecting the sampling container 13 and the optical fiber 19.

(b) Push the lance 2 beyond the measurement position 23,
While drawing back the lance 2, the sampling container 13 is pushed out and the tip closure 9 is thrown into the furnace.

(c) Further, the lance 2 is pulled back, the sampling container 13 is set at the measurement position, and the melt is sampled.

At the same time, temperature measurement using the optical fiber 19 is started. Since the measured temperature value fluctuates due to the movement of the charge in the furnace, etc., the average every 30 seconds and the fluctuation σ are processed by a computer and output.

(d) After completing the melt sampling, pull the sampling container 13 back into the lance 2.

[Effect of idea]

The present invention makes it possible to simultaneously sample the molten material in a vertical furnace and measure the temperature of the molten zone, greatly contributing to the analysis of vertical furnaces. Since the optical fiber is installed in the cooling pipe, there is no need for gas cooling, which reduces the amount of purge gas and improves measurement accuracy.

FIG. 5 shows an example of temperature measurement data. For purging
When the amount of N ₂ was reduced by half, a nearly constant value was obtained even during melt sampling, indicating that the device with the temperature measurement function of the present invention can measure with high accuracy without the influence of N ₂ purge.

Figure 6 shows the relationship between the temperature in the furnace and the [Si] concentration in hot metal when actually sampled.

Generally, there is a positive correlation between temperature and [Si] even when powder injection is not performed (indicated by a white circle in the figure). When powder (iron ore) is injected (indicated by a black circle in the figure), the temperature decreases and the relationship between temperature and [Si] also shifts to the lower temperature side. Performing such measurements has excellent effects, such as making it possible to elucidate the reaction mechanism during powder injection.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a charge sampling device according to an embodiment of the present invention, Fig. 2 is a partially sectional side view of the entire lance equipped with the sampling device of the present invention, and Fig. 3 is a side view of the sampling container. FIG. 4 is an explanatory diagram showing the operation of the melt sampling device, FIG. 5 is a graph of an example of temperature measurement, and FIG. 6 is a graph showing the relationship between the Si concentration and the furnace temperature. 1... Coke packed bed, 2... Lance, 2a...
...Outer pipe, 2b...Middle pipe, 2c...Inner pipe, 3...Ball valve, 4...Gland packing, 5...Guide roller, 6...Dolly, 7...Cylinder, 8...Guide frame, 9...Tip closure, 10...Pipe, 12...Purge piping, 13...Sampling container, 14...Insulating packing, 15...Alumina paste, 18...Drive handle, 19...
Optical fiber, 20... Optical fiber protection tube, 21...
... _N2 introduction pipe for purging, 22...Cooling water channel, 24
……transportation.

Claims (1)

[Claims for Utility Model Registration] The outer tube 2a, the middle tube 2b, and the inner tube 2c are arranged in a triple tube shape, and the gap between the outer tube 2a and the middle tube 2b and the middle tube 2
In a cooling lance-type melt sampling device for sampling the melt in a vertical path, in which a cooling water channel 22 is provided in the gap between the inner tube 2c and the inner tube 2c, the following (a):
characterized by comprising (b), (c), (d) and (e);
Melt sampling device with measurement function. (a) An optical fiber protection tube 20 is disposed extending from the outer end of the lance 2 to the inner end of the furnace, passing through a cooling water channel 22, and is connected to a gas introduction pipe 21 for introducing purge gas. (b) Optical fiber 19 for in-furnace temperature measurement housed in optical fiber protection tube 20. (c) A melt sampling container 13 is housed in the inner tube 2c and is provided so as to be able to protrude in front of the furnace inner end of the lance 2. (d) Moving means 24 for moving the melt sampling container 13 in the longitudinal direction of the lance 2. (e) A tip fitted to the inner end of the lance 2 to protect the sampling container 13 and the tip of the optical fiber when the lance is inserted into the furnace, and to be able to fall off when the melt sampling container 13 is protruded into the furnace. Closure.