JP2833449B2 - Abnormality detection method for coke dry fire extinguishing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting an abnormality such as breakage of a boiler tube of a waste heat boiler during operation of a coke dry fire extinguishing system.

[0002]

2. Description of the Related Art Conventionally, fire extinguishing red hot coke from a coke oven has been carried out by using a wet fire extinguishing method, in which a fire extinguishing truck loaded with red hot coke is moved to a fire extinguisher tower and a large amount of water is sprinkled from the top to extinguish the fire. I was However, the wet fire extinguishing of red hot coke causes not only the huge amount of heat of red hot coke to escape to the atmosphere as steam, but also the coke breeze scattered around the surroundings due to the generated water vapor, which poses a pollution problem. Will be raised. For this reason, the recent mainstream fire extinguishing of red hot coke is a coke dry fire extinguishing that can effectively utilize the huge amount of heat possessed by red hot coke, improve coke quality, and solve or reduce the problem of dust pollution.

[0003] The coke dry fire extinguishing system receives red-hot coke carbonized in a coke oven in a coke bucket mounted on a bucket truck, and winds the coke bucket on a top of a cooling tower comprising a pre-chamber and a cooling chamber by a hoist. After the top lid is opened and charged, the heat is exchanged with the circulating inert gas introduced from the circulating inert gas inlet provided at the lower part of the cooling chamber below the pre-chamber to cool to about 200 ° C. , And a fixed amount is sequentially cut out by a coke cutting device at the bottom and is conveyed to a blast furnace. The inert gas heated to nearly 800 ° C by exchanging heat with red-hot coke passes through a small flue provided around the boundary between the pre-chamber and the cooling chamber, and passes through an annular flue in the outer wall of the pre-chamber. After reaching the road, the primary dust is removed by a primary dust remover made of dust-grating bricks installed in the flue, and then introduced into a waste heat boiler to recover heat.
Secondary dust is removed by a cyclone or the like, and the dust is blown again by a circulation blower from a circulation inert gas injection port provided at a lower portion of the cooling chamber.

Most of the circulating inert gas in the coke dry fire extinguishing system is nitrogen gas and carbon dioxide gas, and also contains flammable hydrogen gas and carbon monoxide gas generated from red hot coke. For this reason, the circulating inert gas burns flammable hydrogen gas and carbon monoxide gas by the dilution air blown in the flue so as not to enter the explosion limit. Furthermore, periodic inspections are required by the Industrial Safety and Health Law for waste heat boilers of coke dry fire extinguishing systems.

As a method for detecting an abnormality such as breakage of a tube of a waste heat boiler of the above coke dry fire extinguishing equipment, small coke or powder coke into the boiler is determined by a pressure difference between measured values of a boiler inlet / outlet and a pressure gauge installed inside the boiler. If the estimated amount of deposits exceeds a predetermined value, the deposited coke is broken and flows down inside the boiler together with the circulating inert gas, and the coke collides with the boiler tube and friction causes the boiler. Method for predicting occurrence of tube breakage (Japanese Unexamined Patent Publication No. 3-217)
No. 488), an abnormality such as water leakage due to breakage of a boiler tube is measured by analyzing the gas components of the gas circulation system to measure the component ratios of hydrogen, carbon monoxide, carbon dioxide, and oxygen. The water component ratio determined from the mass balance is obtained, and when the calculated water component ratio value is negative or lower than a predetermined value, and when the actual value of the water component ratio is measured, the water component ratio is measured. (Japanese Patent Application Laid-Open No. 64-51490) has been proposed, for example, when the difference between the calculated value and the actual value is larger than a predetermined value, and it is determined that the boiler tube is leaking.

[0006]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No. 3-217 is disclosed.
The method disclosed in Japanese Patent No. 488 has a tendency that the boiler tube is frequently damaged when the amount of deposited coke increases in the initial coke dry fire extinguishing equipment. In addition, measures have been taken to reduce the adhesion and deposition of coke in the boiler, reducing the frequency of boiler tube breakage caused by abrasion due to collision and friction of the deposited coke on the boiler tube. I have. For this reason, the frequency of boiler tube breakage due to disturbance factors other than the deposited coke has recently increased, and errors in estimation accuracy have increased, making it difficult to maintain estimation accuracy. Also, the method disclosed in JP-A-64-51490 requires analysis of hydrogen, carbon monoxide, carbon dioxide, oxygen, water and a number of gas components, and it is necessary to continuously measure these components. Is technically difficult, and it usually takes several minutes to analyze such a large number of gas components with a single analyzer. Therefore, in order to immediately detect water leakage due to fluctuations in gas components, for example, (Analysis It is necessary to install a considerable number of gas analyzers such as (the number of target gas components to be performed) × (the number of measurement points). On the other hand, gas analyzers are large-scale, such as gas dedusting equipment, dehumidifying equipment, and gas component analyzers, and the equipment costs are quite large.Installing several of these equipments requires too much capital investment. This is unsuitable for an abnormality detection system.

An object of the present invention is to provide a coke dry-type fire extinguishing system that can detect an abnormality in a waste heat boiler at an early stage by using a sensor conventionally installed in a normal coke dry-type fire extinguishing system without installing a new sensor. An object of the present invention is to provide an abnormality detection method.

[0008]

Means for Solving the Problems The present inventors have conducted various tests and studies to achieve the above object. As a result, water leakage from the boiler tube is caused by minute boiler tube breakage, which is often overlooked with only the instantaneous value by monitoring the average value of the instantaneous value of the difference between the amount of water supplied to the boiler and the amount of steam generated from the boiler. Make it possible to detect the amount of water leakage
And arrived at the present invention.

[0009] The present gun onset Ming, in the abnormality detecting method of the waste heat boiler of the coke dry quenching facility, determine the instantaneous value of the flow rate difference by calculating the flow rate difference between the water supply and the generation amount of steam in the waste heat boiler after, before further predetermined within a predetermined time
Serial obtains an average value of the instantaneous value, before Kisho the average value of the instantaneous value of the constant time, compares the set value determined in advance, before Kisho in constant time
An abnormal detection method of the coke dry quenching equipment and judging exceeds setpoint of the mean value of the instantaneous value is predetermined as a boiler tube failure.

[0010]

According to the present invention, sensors for detecting the amount of water supplied to a waste heat boiler and the amount of generated steam, which are installed in an ordinary coke dry-type fire extinguishing system for operation monitoring, are used. And input the calculation result to the boiler tube breakage detection device. And in the present invention, after obtaining the instantaneous value of the flow rate difference by calculating the flow rate difference between the water supply and the generation amount of steam in the waste heat boiler, the more the average value of a predetermined said instantaneous values within a predetermined time Ask. When the boiler tube is damaged, a flow difference occurs between the amount of water supplied to the boiler and the amount of generated steam due to water leakage and steam leakage from the damaged portion. The average value of the instantaneous values of a predetermined within a predetermined time from an instantaneous value of the flow rate difference is compared with a predetermined set value, the set value of the average value in a predetermined time instantaneous value of the flow rate difference is predetermined beyond by determining the boiler tube failure, it becomes possible to detect the water leakage due to instantaneous values alone are often overlooked fine small boiler tube breakage flow rate difference between the water supply and the steam generation amount. Incidentally, average value of instantaneous values in a predetermined time, a predetermined instantaneous value of the predetermined time
Even the average value as it is renewed at regular intervals,
May be moved Dotaira average value of a predetermined in a predetermined time instantaneous value.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the method of the present invention will be described below with reference to FIGS. FIG. 1 is an explanatory view of a device configuration such as a sensor and a computing unit in a coke dry-type fire extinguishing apparatus for carrying out the present invention, and FIG. 2 is a sequence diagram of a boiler abnormality detection system of the present invention. In FIG. 1, reference numeral 1 denotes a cooling tower including a pre-chamber 2 and a cooling chamber 3; 4, a coke bucket for loading red-hot coke kiln discharged from a coke oven; 5, a bucket truck for transporting the coke bucket 4; Then, the coke bucket 4 loaded with red hot coke is wound up and traversed to just above the cooling tower 1, the charging lid 7 of the pre-chamber 2 is opened, and red hot coke is charged.

Reference numeral 8 denotes a circulating inert gas inlet provided at a lower portion of the cooling chamber 3, and the red hot coke descending in the cooling tower 1 is:
It is cooled to about 200 ° C. by heat exchange with the circulating inert gas blown from the circulating inert gas inlet 8, and is sequentially cut out by the coke cutting device 9 at the bottom of the cooling chamber 3, and the next process is performed by the conveyor 10. Transported to The circulating inert gas heated to about 800 ° C. by heat exchange with the red hot coke reaches the flue 12 via the annular flue 11 on the outer periphery of the pre-chamber 2, and is subjected to primary dust removal by a primary dust remover (not shown). After the heat is recovered in the waste heat boiler 13 and further dust is removed in the cyclone 14, the heat is blown from the circulation inert gas inlet 8 by the circulation blower 15.

[0013] 21 is a sensor for pressure detection provided in the pre-chamber 2, and outputs the detected pressure to the pre-chamber pressure controller 2 2. Pre-chamber pressure controller 2
2 compares the pressure in the pre-chamber 2 input from the sensor 21 with a predetermined pressure set value, and opens the upper dissipation valve 24 or the lower dissipation valve 25 when the pressure in the pre-chamber 2 exceeds the set value. Gas is released to control the pressure in the pre-chamber 2 to a set value .

Reference numeral 27 denotes a sensor for detecting the amount of water supplied to the waste heat boiler 13, and reference numeral 28 denotes a sensor for detecting the amount of steam generated by the waste heat boiler 13. The amount of water supplied and the amount of steam detected by the sensors 27 and 28 are as follows. It is output to the flow difference calculator 29. The flow rate difference calculator 29 calculates a flow rate difference from the amount of water supplied to the waste heat boiler 13 and the amount of generated steam input from the sensors 27 and 28, and calculates the instantaneous value and the predetermined time of the instantaneous value .
Seeking average value, a predetermined set value (e.g. 5.0T /
h), when the average value of the instantaneous values exceeds the set value , the boiler tube breakage detecting device 26 is configured to output the average value. Boiler tube breakage detection device 26, as shown in FIG. 2, the average value of the predetermined time of the instantaneous value input from the flow rate difference calculator 29 based on the signal exceeds the set value, determines the boiler tube failure , An alarm is issued, and a command is issued to stop the combustion air fan (not shown), stop coke extraction, stop coke charging, open the in-system gas release valve, and in-system nitrogen gas purge .

With the above construction, if the boiler tube is broken, the sensor 27 for detecting the amount of water supplied to the boiler due to water leakage or steam leakage from the damaged part.
And a flow rate difference is generated between the sensor 28 for detecting the generated steam amount. The flow rate difference calculator 29 calculates the flow rate difference between the supplied water amount and the generated steam amount, and calculates the instantaneous value of the flow rate difference within a predetermined time.
Seeking the average value is compared with the set value which are input in advance (e.g. 5.0T / h), the flat <br/> average value in at a constant time of the flow rate difference exceeds the set value, the A signal is output to the boiler tube breakage detection device 26.

The boiler tube breakage detecting device 26 detects the flow rate difference input from the flow rate difference calculator 29 within a predetermined time.
Based on the signal with the average value exceeds a set value, commanding the necessary treatment. Thus, in this invention, since it becomes possible to detect the water leakage due to instantaneous values alone are often overlooked fine small <br/> boiler tube breakage flow rate difference between the water supply and the generated steam amount, Bo It is possible to improve the accuracy of judging whether or not the tube is damaged.

[0017]

As described above, according to the method of the present invention, damage to the boiler tube of the coke dry fire extinguishing system can be prevented.
In addition to high-precision detection, there is no need to install sensors because existing sensors are used, and equipment costs can be reduced.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a device configuration such as a sensor and a computing unit in a coke dry-type fire extinguishing apparatus that implements the method of the present invention.

FIG. 2 is a sequence diagram of a boiler abnormality detection system according to the method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cooling tower 2 Prechamber 3 Cooling room 4 Coke bucket 5 Bucket truck 6 Hoisting machine 7 Charging lid 8 Circulating inert gas inlet 9 Coke extraction device 10 Conveyor 11 Annular flue 12 Flue stack 13 Waste heat boiler 14 Cyclone 15 Circulation blower 21, 27, 28 Sensor 22 Pre-chamber pressure controller 24 Upper release valve 25 Lower release valve 26 Boiler tube breakage detector 29 Flow rate difference calculator

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shizuyoshi Matsunami 1850 Minato, Wakayama-shi, Wakayama Sumitomo Metal Industries, Ltd. Wakayama Works (72) Inventor Shuji Saeki 4-5-33 Kitahama, Chuo-ku, Osaka-shi, Osaka Sumitomo Metal Industries Co., Ltd. (72) Inventor Yutaka Hirata 4-5-33 Kitahama, Chuo-ku, Osaka City, Osaka Prefecture Sumitomo Metal Industries Co., Ltd. (56) References JP 50-152790 (JP, A) JP 48-1603 (JP, A) JP-A-2-44102 (JP, A) JP-A-2-11804 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F22B 37 / 42 C10B 41/00

Claims (1)

(57) [Claims] In a method for detecting an abnormality in a waste heat boiler of a coke dry fire extinguishing system, an instantaneous value of the flow difference is obtained by calculating a flow difference between a water supply amount to the waste heat boiler and a generated steam amount .
After further predetermined to obtain an average value of the instantaneous values within a predetermined time period, the average value of the previous Kisho instantaneous value of the constant time, predetermined
It was compared set value, before Kisho abnormality detection of the constant mean value of the instantaneous value of time in exceeds the set value of <br/> predetermined the coke dry quenching facility characterized by determining the boiler tube failure Method.