JPS5913935A - Method and device for detecting rupture of piping for cooling blast furnace - Google Patents

Abstract

PURPOSE:To detect exactly the rupture of a cooling pipe by providing a gas- liquid separator provided with spiral grooves on the inside surface of the sampling piping for the cooling water of a blast furnace body thereby assisting the dissolution of gaseous CO into the sampling water and analyzing exactly the dissolved CO. CONSTITUTION:The sampling water 8 carrying CO foam introduced from a cooling piping ascends in an inside cylinder 1a. Spiral grooves are provided in the cylinder 1a, due to which the contact time between foam and water is longer and the foam dissolves thoroughly in the water. The sampling water 9 separated of foam is conducted from the bottom end part of the cylinder 1b through a sampling piping 11 to a dissolved CO detector which detects the rupture of the cooling piping by measuring the value of the dissolved CO in the water. The contamination by the gaseous CO in the piping and detector is eliminated and the exact measurement is accomplished.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for detecting damage to blast furnace body cooling piping by measuring dissolved Co in blast furnace body cooling water.

During operation, a blast furnace cools the furnace body by circulating cooling water, but the cooling piping can be damaged due to overheating, etc. If the cooling piping is damaged, it may cause poor cooling or water intrusion into the furnace. This will hinder operations. Therefore, damage to the cooling piping must be detected early and necessary measures taken.

If a cooling pipe breaks, CO gas generated from the blast furnace dissolves into the cooling water, so conventionally, an effective detection method for detecting damage to the cooling pipe is to measure dissolved CO in the cooling water of the blast furnace body. It has been used as. For this reason, a method has been adopted in which cooling water is sampled from a required location in the cooling piping, and dissolved CO in the cooling water is analyzed and detected using a detector. However, in conventional methods, when attempting to analyze CO in multiple sampled waters using the same detector, if Co bubbles are present in the sampled water, fine CO bubbles may adhere inside the detector or sampling piping. , remaining and contaminating the sampled water to be analyzed next with Co, often giving a positive error to the CO measurement value and falsifying the measurement. In addition, even if resampling is performed in places where air bubbles are difficult to enter in the piping in an attempt to avoid this phenomenon, CO bubbles will travel along the pipe wall surface and become nucleated.
When the temperature rises, it is difficult for the solution to enter the water, so there is a drawback that even though CO is present due to damage to the cooling piping, it is not detected as dissolved CO.

An object of the present invention is to improve the shortcomings of the conventional methods as described above, and to provide a method and apparatus capable of accurately detecting damage to cooling piping by accurately analyzing dissolved Co in cooling water. That is. That is, the present invention separates air bubbles from the cooling water sampled from a required location of the blast furnace body cooling piping, and then guides the cooling water to the dissolved CO detector via a switching valve that can switch the cooling water to the bypass piping. C in cooling water
This method is characterized by measuring the O value and detecting damage to the cooling pipe based on the measured value.

Embodiments of the method and apparatus of the present invention will be described in detail below with reference to the drawings.

In FIG. 1, 2, 2. ', 2'' are blast furnace body cooling water pipes, and sampling water outlets are provided at required locations of the pipes 2., 2', 2"..., and gas-liquid separators 1゜lj, ]'' ...to be concatenated. Cooling pipe 2・
The sampling water outlet of... and the gas-liquid separator 1...
It is preferable to provide a valve between the tank and the tank that can open and close the flow of sampling water.

FIG. 2 is an enlarged sectional view of the gas-liquid separator 1, illustrating the state in which air bubbles are separated from sampled water. This gas-liquid separator 1 consists of an inner cylinder 1a that communicates with a sampling water outlet of a cooling pipe 2 via a valve, and an outer cylinder 1b that the inner cylinder 1a penetrates from below. The upper end of the inner cylinder 1a is open leaving an appropriate space above the outer cylinder 11), the upper end of the outer cylinder 1b communicates with the air vent pipe via the air bubble valve 6, and the lower end of the outer cylinder 1b is open. It communicates with a sampling pipe 11 toward the dissolved CO detector 10 on the side of the penetration part of the inner cylinder 1a. Sampling water 8 accompanied by CO bubbles introduced from the cooling pipe 2 rises inside the inner cylinder 1a, but a spiral groove is provided in the sampling water passage of the inner cylinder 1a, so that the air bubbles can flow through the inner cylinder 1a. Since it rises along the spiral groove, the contact time with water is extended, and it is configured to be sufficiently dissolved in water. The air bubbles that have risen inside the inner cylinder 1a and have not been completely dissolved in the water are separated from the water from the upper end of the inner cylinder 1a and accumulate at the upper part of the outer cylinder 1″D as a surplus gunu 7. In addition, the inner cylinder 1a
It is desirable that the outer cylinder 1b be made of transparent glass so that the state of bubble separation can be determined from the outside. On the other hand, the sampling water 9 from which air bubbles have been separated as described above is transferred to the outer cylinder 1.
Dissolved CO from the lower end via the sampling pipe 11
The sampled water is guided to a detector 10, where dissolved CO in the sampled water is analyzed. A switching valve 4, which is a three-way valve, is provided at the front part of the sampling pipe 11 leading to the dissolved CO detector 10, and is connected to the gas-liquid separation type 1: a pipe line that leads the incoming sump water to the detector 1o. When the detector 1o is not used for analysis, the switching valve 4 is switched to allow the sampler water to flow through the bypass pipe 5 and into the original cooling pipe. return.

In actual blast furnace operation, a large number of cooling pipes 2
, 2', 2", etc. Therefore, as shown in Fig. 1, it is necessary to perform damage detection on each of the cooling pipes 2. Separate cooling water into gas and liquid separately? J.P.J.
Bubbles are separated by l, f, 1*... and guided to a dissolved CO detector]0 via tampling pipes 1.1, l1', 11'', and analyzed for dissolved CO in each sampled water. Sampling piping 11
, 11', l l''-- are provided with switching valves 4, 4', 4 in the Aft section of the dissolved CO detector 10, respectively.
'... are provided, and when sampling water is sent to the detector 10 from one switching valve 4 for analysis, the other switching valves 4', 4''... The sampling water is switched to the bypass pipe 5 and returned to the cooling pipe, and thus the switching valves 4, 4', 4
``By sequentially switching..., it is possible to continuously measure and analyze sampled water from different locations using the same dissolved CO detector 10.'' Two switching valves 4.4', 4"... and the piping before and after the water switching device 3 is constructed.

FIG. 3 is a graph showing a time-series change in the measured value of dissolved Co in the sampled water measured by the dissolved Co detector 1o. Curve A in the figure shows a state in which a part of the reactor body cooling piping is damaged and CO gas in the reactor mixes into the cooling water, and the dissolved Co value rises rapidly. It shows a tendency to start decreasing after the current state continues for about 30 minutes. Curve B shows a state in which there is no damage to the piping, and the melted Co value tends to increase slightly when the furnace body cooling water is circulated, but the difference from curve A in the case of damaged piping is clear. Curve C] shows a state where the cooling water is not circulating, and the fluctuations in the dissolved Co value are hardly detected. In this way, it becomes possible to detect damage to the blast furnace body cooling piping based on fluctuations in the dissolved CO measured value by the dissolved C detector 10 and take necessary measures immediately.

As mentioned above, the method for detecting damage to blast furnace body cooling piping according to the present invention involves separating air bubbles from the cooling water that has been injected from a required location in the blast furnace body cooling piping, and then bypassing the cooling water. Switching valve 4 capable of switching to piping 5
, 4', 4"... to measure the dissolved Co value in the water, and the measured value t is used to detect damage to the cooling pipe. In this case, After separating air bubbles from the cooling water that has been sampled separately from multiple locations, the switching valve (switching sequentially through the switching valve) is used to perform continuous measurements using the same dissolved CO detector. In addition, the blast furnace body cooling piping damage detection device according to the present invention can detect damage to the dissolved CO detector from required locations in the blast furnace body cooling piping 2, 2.', 2.''... Sample link piping 11゜11
' , 1-1・1 is provided, and the gas-liquid separator 1 , ], , 1- is provided to separate air bubbles in water in the sample link piping.
... and a switching valve that can switch between the pipeline to the dissolved CO detector 10 and the pipeline to the bypass piping,
In this case, multiple sample link pipes 11, l], 117...
It is also possible to have a plurality of gas-liquid separators 1, 1', 1'', . . . and a plurality of switching valves 4, 4', 4'', .

According to the present invention, by providing a gas-liquid separator with a spiral groove on the inner surface of the blast furnace body cooling water sampling pipe,
In addition to promoting CO gas dissolution into the sampling water,
Air bubbles in the sampling water can be completely removed.

Therefore, since the sampling water in which CO gas is completely dissolved and is not accompanied by CO bubbles can be guided to the detector, the contamination caused by COt in the piping and detector as described above is eliminated, and the dissolved COt by the detector is eliminated. Accurate measurement of CO values is ensured. In addition, as shown in ``-2'', the switching valves 4, 4'', 4M・
By sequentially switching and measuring..., the amount of dissolved CO in sampled water from each location can be measured continuously and accurately using the same dissolved C○ detector, so the entire system can be constructed at low cost. becomes possible.

According to the method and apparatus of the present invention, as shown in FIG. C of
It is possible to detect even the slightest dissolved state of Oganu. Therefore, it is extremely effective in appropriately detecting the condition of the blast furnace body cooling piping and enabling prompt response.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing a specific example of an apparatus implementing the present invention, Fig. 2 is an enlarged cross-sectional view of a gas-liquid separator showing the separation state of bubbles, and Fig. 3 is a diagram showing dissolved Co in sampled water. It is a graph showing a time-series transition of measured values. 1,],', :,," Gas-liquid separator 2,
2', 2" Furnace body cooling piping 4, 4', 4"
Switching valve 5 Bypanu piping 10 Dissolved CO detector Patent applicant Nisshin Steel Co., Ltd.

Claims (1)

[Claims] l After separating air bubbles from the cooling water sampled from the required locations of the blast furnace body cooling piping, the sampled water is passed through a switching valve that can switch to the bypass piping to collect dissolved CO.
A method for detecting damage to a blast furnace body cooling pipe, comprising: measuring a dissolved CO end in water by guiding it to a detector, and detecting damage to the cooling pipe based on the measured value. 2. Claim No. 2, characterized in that after air bubbles are separated from the cooling water sampled separately from a plurality of locations, the switching valves are used to sequentially switch the cooling water and the same dissolved CO detector is used to continuously measure the cooling water. The method for detecting damage to a blast furnace body cooling pipe according to item 1. 3 Sampling piping is installed from the required point of the blast furnace body cooling piping to the dissolved CO detector, and in the sampling piping there is a gas-liquid separator that separates air bubbles in the water, and the piping and bypass piping to the dissolved Co detector. A damage detection device for blast furnace body cooling piping, which is equipped with a switching valve that can switch between the piping and the piping. 4 Claim 3, characterized by having a plurality of sampling pipes leading from a plurality of locations to the same dissolved Co detector, a plurality of gas-liquid separators, and a plurality of switching valves. A device for detecting damage to blast furnace body cooling piping as described in 2.