JPH02101104A - Method and device for measuring combustion zone depth in a blast furnace - Google Patents

Abstract

PURPOSE:To measure depth of combustion zone under safe work without making furnace condition unstable by inserting a measuring rod into the furnace from a tuyere while preventing the furnace contents from spouting out by higher pressure gas than inner pressure of the furnace. CONSTITUTION:A peel hole cock 1 in the tuyere in the blast furnace and a branching pipe 2 are connected, and the tip part of the measuring rod 21 is inserted into a sealing metal fitting 6. A cock 5 is wholly closed and a compressed gas main valve 11 is wholly opened. The peep hole cock 1 in the tuyere and the cock 5 are opened and the tip part of the measuring rod 21 is inserted to the deepest part 15 in the combustion zone through the tuyere 14 in the furnace. Under this condition, marking is executed on the measuring rod 21 at the tip position of the sealing metal fitting 6 and the measuring rod 21 is pulled out. When the tip part of the measuring rod 21 reaches to the position of the sealing metal fitting 6, the cocks 1, 5 are wholly closed. The measuring rod 21 is perfectly pulled out and the compressed gas main valve 11 is closed and a valve 10 for discharging remaining pressure is opened. The distance from the tip part of the measuring rod 21 to the marked position is measured. By this method, the depth of the combustion zone can be measured without needing the pressure reduction.

Description

Detailed Description of the Invention (Field of Application of Industry-1-) The present invention uses a gas having a higher pressure than the internal pressure of the blast furnace to increase the depth of the combustion zone in the blast furnace without reducing the internal pressure of the blast furnace. Also, is it easy and safe to release the pressure inside the furnace to the outside air? A method and apparatus for measuring this.

(Prior art) Conventional depth measurements in the combustion zone of a blast furnace require the high-pressure blast furnace to be partially opened, and from the standpoint of health and safety for the human bodies of those measuring nearby, the pressure inside the furnace is lower than the normal 3. , 5 Kg/
We have reduced the pressure (wind reduction) from the "cm" level to I, OKy, /ct*'.This is shown in Figures 2, 3, and 4.
This will be explained using figures.

First, the internal pressure of the blast furnace is reduced (air reduction) to I, OKg/cm2, and a worker wearing ear plugs and a heat-resistant windshield opens the measurement port 17 installed in the metal fittings 16 of the tuyere 1 through the tuyere 1-
1 peep] - 1 Move to the mouth of the 1 window cock. This is done by removing the mounting bolt 19 that fixes the tuyere viewing hardware 16 and loosening the fulcrum bolt 18 that allows the tuyere viewing hardware 16 to move.

Next, the operator operates the lever 20 for moving the tuyere metal fittings, aligns the measurement-dedicated opening 17 with the opening of the tuyere viewing window cock 1, inserts the measuring rod (round steel) 21, and - In-furnace tuyere 14
Measurement round steel 21 up to the deepest part 15 of the combustion zone ahead of
is pushed in, a mark is made on the measuring rod 21 using the measuring port 17, and the measuring rod 21 is immediately pulled out to the outside of the blast furnace.

Next, the tuyere metal fitting 16 is returned to its original position, the mounting bolt 19 is attached, and the fulcrum bolt 18 is tightened. After confirming that no high-temperature hot air is blown out from inside the furnace, the measurement of the combustion zone is completed.

After that, the pressure of the blast furnace is increased (air increase) to the original operating level, i.e. 1
, 0 Kg/an'' to 3.5 Kg/cm', the depth measurement work of the combustion zone is completed.

In this case, the operator operates the lever 20 for moving the tuyere hardware and aligns the measurement opening 17 with the opening of the tuyere peephole cock 1, then inserts the measuring rod 21 and pulls it out to measure. In the conventional working environment, until the tuyere fitting I6 is returned to its original position and the mounting bolt 19 and mounting fulcrum bolt 18 are tightened, the user is exposed to the ejected high-temperature hot air 24 and in-furnace fuel 25. This is the reality.

(Problem to be Solved by the Invention) In the conventional method for measuring the depth of the combustion zone, measurement cannot be performed unless the pressure inside the furnace is reduced (reduced air) and the pressure inside the furnace is further released to the atmosphere. However, by reducing the pressure inside the furnace (reducing air), the rate of descent of the contents in the furnace and the ventilation inside the furnace change, which disturbs the flow of gas generated inside the furnace.

As a result, the furnace conditions become unstable, causing fluctuations in the heat level and composition of the hot metal slag, and problems such as a delay in pressure increase (air increase) often occur. These factors also caused an increase in the cost of hot metal.

In addition, since depressurization (air reduction) is always required, it is difficult to carry out numerous measurements, and the number of data is small, and the measured values are on average about 5% lower than the measured values during normal operation.
It was found that the depth of the 2% combustion zone became shallower.

Comparing the measurement results of the combustion zone during normal operation and when the furnace pressure is reduced to 1.0 Kg/am'' using the combustion zone depth measuring device according to the present invention, the average depth measurement result during normal operation is 111.
At 5 m/s, the average speed at reduced pressure was 584 m/m, and the difference was 531 yh/m on average. Therefore, the conventional method has a problem in that the measured values are unreliable and cannot be used effectively for analysis of blast furnace operations. For this reason, it is necessary to increase the number of measurements of the combustion zone in order to ensure stable operation of the blast furnace, but it is not possible to increase the number of measurements, and there is a method to measure the depth of the combustion zone under normal operating conditions without reducing the pressure (air reduction). It has been desired for many years.

In addition, by releasing the pressure inside the furnace to the atmosphere, the measurement operator can
In addition to significant noise (more than 120 horns) due to the release of the furnace internal pressure to the atmosphere, high-temperature hot air mixed with red-hot dust blows out 24 (approx.
The work was both mentally and physically painful as they were exposed to temperatures of 25,000 degrees Celsius and in-furnace fuel (coke, etc.).

(Means for Solving the Problems) The present invention is a method for measuring the depth of a combustion zone by inserting a measuring rod from a blast furnace tuyere. prevents the eruption of
This is a method of measuring the depth of the combustion zone in a blast furnace without reducing the pressure inside the furnace, and in order to carry out this method, a cock and seal hardware are installed on the horizontal leg of the bifurcated pipe that can be connected to the tuyere peephole cock. , and a high-pressure gas introduction part is disposed at the other foot of the bifurcated tube, and the measuring rod is inserted into the furnace while being sealed by the sealing hardware.

The present invention solves the problems that have been sought for many years but could not be solved at once by using a combustion zone depth measuring device as described below. The entire structure of the combustion zone depth measuring device will be explained with reference to FIG.

(a) Nipples 3-1 are installed at both ends of the bifurcated leg of the bifurcated tube 2, which has an inner diameter thicker than the outer diameter of the measuring rod (usually a round steel) 21.
Connect.

(b) The remaining end of the bifurcated pipe 2 is constructed by screws or other means so that it can be tightly connected to the tuyere sight port cock 1 of the blast furnace.

(c) Nipples 3 connected to both ends of the forked foot of the forked tube 2
Connect cock 5 to one side (horizontal direction) of -1, and
Connect nipple 3-2 to. A nipple 4 with a different diameter is connected to the nipple 3-2, and then a metal seal 6 containing a seal packing 7 having a function of suppressing leakage of the gas pressure source from the direction of the cock 5 is connected to the nipple 4 with a different diameter.

(d) A seal packing 7 is housed inside the seal metal fitting 6 in the form of a ring having the same inner diameter as the outer diameter of the measuring rod 21.

(E) The other nipple 31 at the foot of the bifurcated tube 2 has a
The fitting 8, which can be connected with one touch, forms a high-pressure gas introduction section.

(f) Attach the other end of the joint 8 to the rubber pose 9.

(g) A pressure gauge 13 is installed in the compressed gas supply pipe 12 to check the supply pressure, and then the compressed gas source valve I+ is installed as shown in the figure.
, a joint 8 is provided, and a residual pressure relief valve IO is provided therebetween.

(Function) Combustion zone depth measuring device - Measuring rod 2 inside seal hardware 6
When the cock 1 is inserted, the cocks 1 and 5 are fully closed.

Then, by fully opening the compressed gas source valve +1,
Between them there is a compressed gas, e.g. a pressure cuff higher than the furnace pressure.
, 0 Kg/cm' of compressed air will be applied,
When the window cock 1 is fully opened at once, the compressed gas pressure overcomes the pressure inside the furnace, and compressed gas enters the inside of the furnace. The reason why the bifurcated portion of the -membrane tube 2 is angled is to allow the maximum compressed gas pressure to enter the tuyere peephole cock l side (inside the furnace).

Even when the cock 5 is fully open and the measuring rod 21 is inserted into the deepest part 15 of the combustion zone through the tuyere 14 in the furnace, the compressed gas pressure is greater than the pressure inside the furnace, so hot air from inside the furnace and The depth of the combustion zone can be measured without any ejection of material.

Note that as the compressed gas, gases such as air, nitrogen, and carbon dioxide can also serve the same purpose.

(Example) An example of the present invention will be described with reference to FIG. Fully close the tuyere peep cock L, confirm that the pointer on the pressure gauge I3 of the compressed gas supply pipe 12 is 7.0 Kg/cm or more, and close the compressed gas source valve If and residual pressure release valve IO. Check that it is fully closed.

The tuyere peep cock I and the bifurcated pipe 2 are connected, and both ends of the rubber hose 9 are connected to the joint 8 and the joint 8 on the compressed gas supply pipe side.

Then, the tip of the measuring rod 21 is inserted into the seal metal fitting 6. The above is the set state of the combustion zone depth measuring device before measurement.

Next, the procedure of measurement work will be explained.

Confirm that the cock 5 is fully closed, and close the compressed gas source valve 11.
is fully opened. Then, fully open the tuyere sight cock 1 and the cock 5, carefully insert the tip of the measuring rod 21 into the furnace through the tuyere 14 to the deepest part 15 of the combustion zone, and in this state, close the end of the sealing hardware 6. Make a mark on the measuring stick 21 at the location, and insert the measuring stick 2
Pull it out every time.

When the tip of the measuring rod 21 passes through the cock 5 and reaches the position of the seal metal fitting 6, the pulling operation is temporarily interrupted and the tuyere viewing window cock 1 and the cock 5 are fully closed. Next, measuring rod 2
1 is completely pulled out from inside the seal hardware 6, the compressed gas source valve 11 is fully closed, and the residual pressure release valve 10 is opened. Measure and record the distance from the tip of the measuring stick 21 to the engraved spot.

Thus, the work of measuring the depth of the combustion zone in the blast furnace is completed.

(Effects of the Invention) The present invention (a) eliminates the need for pressure reduction (air reduction), and does not require complicated operations to reduce or increase air.

(b) As a result of the fact that those who measure depth in the combustion zone can now work safely, they no longer need to use safety equipment more than necessary.
The physical load was greatly reduced.

(c) There is no need for pressure reduction (air reduction), and there is no longer any fear that the furnace condition will become unstable by measuring the depth of the combustion zone.

(d) The effects of (a), (b), and (c) make it possible to safely measure the depth of the combustion zone whenever necessary,
In addition, the reliability of the measurement results is improved, which contributes to blast furnace operation analysis, making it possible to operate the blast furnace stably, secure production volume, and stabilize quality.

(e) There is no increase in the cost of hot metal due to depth measurement of the combustion zone.

[Brief explanation of the drawing]

Figures 1 (a) and (b) are side views of the embodiment of the present invention, Figure 2 is a schematic sectional view of the blast furnace main body, Figure 3 is an explanatory diagram of the conventional method, and Figure 4 is the tuyere opening according to the conventional method. It is a front view of hardware equipment. l...Tuyere peephole window cock 2...Bifurcated pipe 5...Cooker...Seal hardware 12...Compressed gas feed tube Furnace tuyere combustion zone Measuring rod dedicated to measuring the deepest part of fuel spewed out inside a high-temperature hot blast furnace - Person Nippon Steel Corporation

Claims (2)

[Claims] (1) In the method of measuring the depth of the combustion zone by inserting a measuring rod from the blast furnace tuyere, gas at a pressure higher than the internal pressure of the blast furnace is used to prevent ejected materials from inside the blast furnace. A method of measuring combustion zone depth in a blast furnace without reducing pressure. (2) A cock and a sealing hardware are provided on the horizontal leg of the bifurcated pipe that can be connected to the tuyere peephole cock, and a high-pressure gas introduction part is provided on the other leg of the bifurcated pipe, and measurements are taken using the sealing hardware. A device that measures the depth of the combustion zone in a blast furnace, configured so that the rod can be inserted into the furnace while being sealed.