JPH08100180A - Measuring of amount of coke shrinkage - Google Patents

Abstract

PURPOSE: To measure distance displacements to the surface of coke during dry distillation by a laser displacement gauge without being inhibited by heat rays and colored gases. CONSTITUTION: This method for measuring an amount of coke shrinkage is to measure the amount of coke shrinkage by irradiating a laser beam from a non-contact laser displacement gauge during a dry distillation of coal 7 inserted in a retort 12 of a test coke oven 10. A sensor box 18 is cooled by feeding N2 gas from a purging gas feed pipe 21 put at the back of the sensor box 18 and, at the same time, a colored gas generated during the dry distillation is removed from the path of the laser beam by blowing N2 gas from the opening of an iron shell box 16. Distance displacements can be measured by cutting heat rays caused by the laser beam reflected from the coke with a hot ray absorbing filter 3 fixed at a ray-intercepting unit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring the amount of shrinkage of coke produced during coal carbonization in a test coke oven over time.

[0002]

2. Description of the Related Art Coke cake oven width direction (horizontal direction)
Since the shrinkage characteristics of the, affect the clearance between the coke cake surface and the heating wall and the coke carbon core,
If the amount of shrinkage is insufficient, there is a risk of defective coke extrusion. Not only will productivity drop due to poor extrusion, but the heating wall will be greatly damaged by excessive lateral pressure from the pusher rod. Such a phenomenon causes a hindering of stable operation of the coke oven and a shortening of the life of the coke oven. Therefore, it is necessary to investigate the influence of coal blending conditions (coal properties) and carbonization conditions (carbonization temperature, carbonization time, charging bulk density, etc.) on the amount of coke shrinkage from the standpoint of stabilizing coke oven operation and prolonging the life of the furnace. .

Generally, the amount of shrinkage of the coke in the oven width direction is investigated by using a small test oven (2 kg to 500 kg).
As the clearance between the coke cake surface and the heating wall,
There are hot and cold. The hot clearance is the clearance where the coke and the heating wall are still in a high temperature state (1000 ° C or higher), and the cold clearance is the clearance measured at room temperature. Clearance needs to be measured.

[0004] Conventionally, as a method for hot measuring the shrinkage amount of coke produced by carbonization of coal in a test coke oven, Ironmaking Proceedings, 45 (1986), p. 453 (see Fig. 13) and Ironmaking Conferrence Proceedings. , p.303,1
993 (see FIG. 14), etc., the rod C charged from the opening B of the furnace wall A is pressed directly against the surface of the coke E by using the cylinder D, and the displacement of the rod C is differentiated. It was read by the transformer type distance meter F. In this case, a certain pressing force is applied to the rod C so that the tip of the rod C follows the contraction of the coke E. If this pressing force becomes inappropriate and becomes too large, phenomena such as compaction into the softened and molten layer and coal layer and destruction of the coke layer (increased cracks) will occur, affecting the contraction phenomenon of coke during carbonization. Given, you cannot measure the true amount of coke shrinkage. When the pushing force is small, the rod cannot follow the contracting surface of the coke, and the true contraction amount of coke cannot be measured. To measure the true amount of contraction of coke, the pushing force applied to the rod must be appropriate, but the pushing force is optimal because the force applied to the coke layer (coke layer surface) during coal carbonization changes with time. Difficult to control.

Therefore, in order to measure the amount of coke shrinkage without the influence of the measuring method, it is desirable to measure without contact. As a non-contact measurement method, a measurement method using waves such as microwave, infrared ray, laser, and ultrasonic wave is well known, but coke is hot (1000 ° C or higher) and precise (measurement accuracy is 0.1 mm or less). The laser displacement meter was the most suitable for measuring the shrinkage amount of. However, even if a laser displacement meter was used, it was not possible to make a measurement due to the influence of the gas generated during coal carbonization and the heat rays emitted from the red hot coke surface that was generated, or even if it was possible, an accurate shrinkage amount could not be obtained.

[0006]

DISCLOSURE OF THE INVENTION The present invention solves the problem that the method for measuring the amount of coke shrinkage affects the amount of shrinkage, and the gas generated during coal carbonization and the heat rays emitted from the generated red hot coke surface are solved. It is intended to accurately measure the amount of coke shrinkage hot and non-contact without being affected.

[0007]

According to the present invention for achieving the above object, a shrinkage amount of coke is measured by irradiating a coke surface during carbonization in a test coke oven with laser light from a non-contact laser displacement meter. At this time, use a heat ray absorption filter to remove heat rays that hinder the shrinkage measurement, and further eliminate the colored gas generated by coal carbonization to ensure the stroke of the laser beam and to cool the laser displacement meter. It is a method of measuring the amount of coke shrinkage, characterized in that an inert gas is purged from the back of the laser displacement meter toward the stroke of the laser beam.

[0008]

[Operation] In the present invention, the heat ray absorption filter is provided in the laser beam receiving portion, and the inert gas is purged to secure the stroke of the laser beam and to cool the laser displacement meter. It is possible to eliminate the influence of the heat ray from the red hot coke surface and the colored gas generated by coal carbonization, which influences the measurement accuracy of.

[0009]

EXAMPLE First, (Example 1) shows an example of distance measurement using a heat ray absorption filter that is not affected by heat rays emitted from the red hot coke surface. In addition, we will describe the situation in which the measurement is hindered because the laser beam is blocked by the colored gas generated during coal carbonization. Next, (Example 2) shows the results of a coke shrinkage measurement experiment during coal carbonization carried out in a small carbonization furnace (40 kg) using a heat ray absorption filter and purging with nitrogen gas.

(Embodiment 1) In FIG. 6, a laser displacement meter 2 is attached to a laser displacement meter 2 in a small retort furnace 1, a heat ray absorbing filter 3 made of heat-resistant glass is attached, and a coke, a brick, and a stainless plate are used as a measurement object 4 on a brick stand 5. An experimental apparatus for measuring the distance to the measurement object 4 by heating the measurement object 4 and then irradiating the surface thereof with laser light from the laser displacement meter 2 is shown.
In addition, 17 shows heat resistant glass.

Table 1 shows the experimental results in comparison with the results of actually measuring the distance to the object to be measured 4 with a measure and the results of the measurement without the heat absorption filter. The measurement temperature was 1050 ° C. As shown in Table 1, none of the red hot coke, the high-temperature brick, and the high-temperature stainless steel plate as a measurement object could be measured due to the heat ray without the heat ray absorbing filter in the laser displacement meter. On the other hand, by using a heat ray filter for the laser displacement meter, the measurement distance to the red hot coke, high temperature brick and high temperature stainless plate was close to the distance actually measured with a measure in all cases, showing that it could be measured accurately. There is.

[0012]

[Table 1]

In order to investigate the situation in which the measurement is hindered by the interruption of the laser beam by the colored gas generated during coal carbonization, the influence of the generated gas was investigated using the experimental apparatus shown in FIG. As shown in FIG. 7, coal 7 is loaded into a crucible 6 placed on a brick stand 5 in a small retort furnace 1, and 1050
Heated to ° C. A stainless steel plate is placed as a measurement object 4 on one end of the upper surface of the retort furnace 1, and a laser displacement meter 2 is provided at a position facing the stainless steel plate. A gas (colored gas) 8 generated from heated coal is emitted from the laser displacement meter 2. While the laser beam 9 was being irradiated, the laser beam was not transmitted and was scattered, which made measurement impossible.

(Example 2) As shown in FIG. 3, a retort 12 is installed on a base 11 of a test coke oven 10 having a capacity of 40 kg, and about 40 kg of coal 7 is charged in the retort 12 to prepare a test coke. The heating element (silicon unit) 13 arranged along the side wall 14 in the furnace 10 is caused to generate heat, and the coal in the retort 12 is carbonized. Reference numeral 25 denotes a recorder for recording the experimental results measured by the laser displacement meter.

As shown in FIGS. 4 and 5, a steel box is provided in a through hole 15 horizontally provided in a side wall 14 of the test coke oven 10.
16 is fixed, and a sensor box 18 incorporating the laser displacement meter 2 is set in the iron box 16. Iron skin box
A heat-resistant glass 17 is attached to the front surface of the furnace inner side of 16, and a heat-resistant glass 17 is attached to the light projecting portion and the light receiving portion of the laser beam on the front surface of the sensor box 18 inside the furnace.
Further, the heat ray absorption filter 3 is provided in the light receiving portion of the laser beam.
Is installed.

Then, a stainless pipe for introducing a cord connected to the laser displacement meter and a cord connected to the thermocouple
N ₂ gas is supplied to 19 to cool them. In addition, since the distance (displacement) to the coke surface cannot be measured if there is a colored gas generated by the carbonization of coal 7 during the process of the laser light, the L-shaped multi-hole nozzle 20 is placed horizontally above the front surface of the furnace inside the iron skin box 16. N ₂ gas is supplied from a purging gas supply pipe 21 connected to one end of the L-shaped multi-hole nozzle 20, and the stroke of the laser beam is purged by the N ₂ gas blown out from the L-shaped multi-hole nozzle 20. On the other hand, a hot test of the amount of coke shrinkage during the carbonization of coal 7 was tried using a 40 kg test coke oven 10.

However, as shown in FIG. 8, even if N ₂ gas is blown out from the L-shaped perforated nozzle 20 arranged in the upper part of the front surface of the furnace inside the iron box 16, soot and tar are immediately attached and the colored gas is purged. Can not be the sensor box
It was not possible to measure the distance to the coke surface in the furnace by the laser displacement meter built into 18. As shown in FIG. 9, a straight nozzle 20A formed in a dogleg shape in front of the iron box 16 is used, and as shown in FIG. 10, a long lid and a nozzle 20B are used to purge with N ₂ gas. The method was tried, but as in the case of FIG. 8, it could not be measured successfully due to soot and tar adhesion.

As shown in FIGS. 1 and 2, the heat-resistant glass 17 arranged on the front surface of the iron-sheath box 16 inside the furnace is removed and opened, and the back of the iron-sheath box 16 is covered with a cover 24. The purge gas supply pipe 21 is exposed to the inside of the iron box 16 to purge N ₂ gas from the rear part of the sensor box 18 to keep the pressure in the iron box 16 at a positive pressure (5 mmH ₂ O or more).

The sensor box 18 is provided with a stainless steel tube 19
From this, the coated wire connected to the laser displacement meter and the lead wire connected to the thermocouple are led.
Supplying ₂ gases and cooling is the same as the case of the above-mentioned test. In FIGS. 1 and 2, the same components as those shown in FIGS. 3 to 5 are designated by the same reference numerals to omit redundant description.

The operation of the present invention will be described. The carbonization state of the coal 7 in the retort 12 installed in the test coke oven 10 is projected from the projection part of a laser displacement meter (not shown) built in the sensor box 18. The generated laser light passes through the heat-resistant glass 17 mounted on the front surface of the sensor box 18 and the heat-resistant glass 17 mounted on the front surface of the iron-clad box, and then passes through the projection process to open the coal 22 from the opening 22 provided in the retort 12. The coke surface 7a generated by dry distillation is irradiated.

The laser beam reflected from the coke surface 7a passes through the opening of the iron box 16 through the reflection process, passes through the heat-resistant glass 17 of the sensor box 18, and further passes through the heat ray absorbing filter 3 of the sensor box 18. Then, the light is received by the laser displacement meter, and the distance (displacement) to the coke is measured from the time difference from the light projecting time to the light receiving time. At this time, in the present invention, when the laser beam including the heat ray reflected from the surface of the coke passes through the heat ray absorbing filter 3 provided on the front surface of the sensor box 18, the heat ray which obstructs the measurement of the coke shrinkage amount is eliminated and the laser displacement is eliminated. The light is received by the meter.

Further, in the present invention, the N ₂ gas supplied from the stainless steel tube 19 cools the cord and the lead wire guided to the sensor box 18, and the sensor box 18 is inserted into the iron box 16 through the cover 24. The N ₂ gas is supplied from the purging gas supply pipe 21 facing the rearward position. N ₂ supplied from the purge gas supply pipe 21
After the gas cools the sensor box 18, the steel box 16
Blowing from the opening of the 40kg side wall 14 of the test coke oven 10
The stroke of the laser beam from the through hole 15 provided in the retort 12 to the retort 12 can be efficiently purged.

For this reason, the coal 7 charged in the retort 12
Since the colored gas generated when carbon dioxide is carbonized is completely excluded from the process of the laser beam, it is possible to reliably prevent the laser beam from being scattered by the colored gas. Table 2 shows a comparison of the experimental results to the completion of the present invention.

[0024]

[Table 2]

As shown in Table 2, according to the purging from the back of the displacement meter according to the present invention, the distance (displacement) to the coke surface during carbonization was measured by a laser displacement meter.
While it was possible to measure for 4.3 hours, when purging with a nozzle in front of the displacement sensor box, (
It became impossible to measure in the short time shown in (). The cause is soot,
It was the adhesion of tar.

Purging from the back of the laser displacement meter of the present invention did not become unmeasurable due to the adhesion of tar and no matter how many experiments were conducted. The bulk density of coal is 725 kg / m ^{3 as a function of the} change over time in the clearance between the retort wall and the coke surface due to the hot shrinkage of the coke measured by the method of the present invention.
And shows a case of 770 kg / m ^3. The experimental conditions are: dry distillation temperature: 1050 ° C, dry distillation time: 4.3 hours, cooling nitrogen gas flow rate: 0.2 Nm ³ / min, retort width: 190 mm.

According to the present invention, as shown in FIG. 11, the clearance can be accurately measured using the laser beam emitted from the laser displacement meter to the coke surface without being affected by the heat ray and the colored gas. It was At this time, since the N ₂ gas was supplied from the rear part of the laser displacement meter, the temperature inside the sensor box was 45 ° C. or less during the entire dry distillation period as shown in the temperature change with time in FIG. 12, and cooling was effective. It turned out that it was done.

[0028]

EFFECT OF THE INVENTION When measuring the shrinkage amount of coke during carbonization in a test coke oven, a heat ray absorption filter for eliminating a heat ray which hinders the shrinkage amount measurement in a laser displacement meter measurement method which is not in contact with the coke surface. In order to eliminate colored gas by coal carbonization, to secure the stroke of the laser beam and to cool the laser displacement meter, the amount of coke shrinkage is hot by purging inert gas from the back of the laser displacement meter. Can be measured accurately over time.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a situation in which a distance to a coke surface is measured by a laser displacement meter installed on a side wall of a test coke oven according to the present invention.

FIG. 2 is a horizontal sectional view of FIG.

FIG. 3 is a vertical sectional view showing a test coke oven.

FIG. 4 is an enlarged vertical sectional view showing a portion A of FIG.

FIG. 5 is a horizontal sectional view of FIG. 4;

FIG. 6 is an explanatory diagram showing an outline of an experimental apparatus for examining the effect of a heat ray absorption filter.

FIG. 7 is an explanatory view showing the outline of an experimental apparatus for examining the influence of a colored gas generated during coal carbonization on the laser process.

FIG. 8 is a plan view showing a purging state by an L-shaped multi-hole nozzle.

FIG. 9 is a plan view showing a purging state by a straight nozzle.

FIG. 10 is a plan view showing a purging condition by a long lid or a nozzle.

FIG. 11 is a graph showing changes in clearance over time.

FIG. 12 is a graph showing the change over time in the temperature inside the sensor box.

FIG. 13 is a cross-sectional view showing a measurement situation using a conventional rod.

FIG. 14 is a cross-sectional view showing a measurement situation using another conventional rod.

[Explanation of symbols]

 1 Small Retort Furnace 2 Laser Displacement Meter 3 Heat Absorption Filter 4 Measured Object 5 Brick Stand 6 Crucible 7 Coal or Coke 8 Generated Gas 9 Laser Beam 10 Test Coke Oven 11 Base 12 Retort 13 Heating Element 14 Sidewall 15 Through Hole 16 Iron Leather box 17 Heat-resistant glass 18 Sensor box 19 Stainless steel tube 20 L-shaped multi-hole nozzle 21 Gas supply pipe for purging 22 Opening 24 Cover 25 Recorder

Front Page Continuation (72) Inventor Koichi Daiichi Kawashima-dori, Kurashiki City, Okayama Prefecture 1-chome (without street number) Inside the Mizushima Steel Works, Kawasaki Steel Co., Ltd. No house number Kawashima Steel Co., Ltd. Mizushima Works (72) Inventor Kenichi Sorimachi Mizushima Kawasaki-dori 1-chome, Kurashiki City, Okayama Prefecture (No house number) Kawasaki Steel Co., Ltd. Mizushima Works

Claims (1)

[Claims] 1. When measuring the amount of shrinkage of coke by irradiating a laser beam from a non-contact laser displacement meter on the surface of the coke during carbonization in a test coke oven, a heat ray for eliminating a heat ray that obstructs the shrinkage measurement. An absorption filter is used to further eliminate colored gas generated by coal carbonization to ensure the stroke of the laser beam, and to cool the laser displacement meter, an inert gas is passed from the back of the laser displacement meter toward the stroke of the laser beam. A method for measuring the amount of coke shrinkage, which comprises purging.