JPS6144113A - Detection of combustion zone before blast tuyere of blast furnace - Google Patents

Abstract

PURPOSE:To detect exactly the number of the coke grains and unreduced iron ore in a raceway and to stabilize the condition of a blas furnace based on the knowledge on the condition of the combustion zone in the furnace by detecting the brightness in the raceway in a blast furnace operation by a sensor. CONSTITUTION:A peep window 3 is formed to the tuyere of the blast furnace 1 and the inside of the in-furnace raceway 11 before the tuyere is monitored by the sensor 5. The brightness sensor of which the visual field 8 is about <=15mm.phi and the reaction speed with the change of light is higher than 1ms is used in this case. The change of the brightness in the raceway according to the quantity of the coke particles or the particles 10 of th unreduced ore powder, etc. is measured by the sensor 4 and is inputted through an amplifier 5 to a particle number counter 6 which counts the number of the instantaneous decrease in the output signal in specified time out of said signal to detect exactly the number of the coke or other particles 10. The result thereof is displayed on a display device 7. The condition of the blast furnace combustion zone is known by such method and the condition of the blast furnace is thus stabilized.

Description

[Detailed Description of the Invention] (Industrial Field of Application) The technical content described in this specification regarding the detection of the condition of the combustion zone in front of the tuyere of a blast furnace is to stabilize blast furnace operation by appropriately grasping the condition of the blast furnace. The aim is to propose development results regarding effective means for achieving this goal.

(Prior art) Hot air blown from the tuyeres at the bottom of the blast furnace body is
In addition to reacting with coke particles in front of the tuyere to burn the coke, the physical energy of the hot air forms a cavity called a raceway in front of the tuyere in the blast furnace.

The coke particles are burned while swirling inside the raceway, but the burned coke is newly supplied into the raceway from the upper part of the raceway and combustion continues. In addition, the particles that descend into the raceway are not only coke, but also raw ore (unreduced ore 1), and the descending, swirling, and combustion conditions of these particles are determined by the blades attached to the blower branch pipe. (It can only be seen through the peephole.)

Understanding raceway conditions such as the falling status of coke particles and raw ore particles in the blast furnace, combustion temperature, and brightness is an important matter for blast furnace operation, and a modest sensor has been proposed and put into practical use. . For example, JP-A-54-109014
As seen in the publication, a high-speed camera or a television camera with a shutter is used to count the number of particles in a blast furnace. The method using a high-speed camera tit, the high-speed camera installed near the tuyere viewing window.
This is a method in which hundreds to thousands of frames are taken over a period of time, and the aA number of particles captured on the film is counted frame by frame. However, with this method, the imaging IT is expensive, and it takes a lot of effort to count the particles in the image.
Furthermore, since there is a limit to the length of the film, there is a drawback that only short-term, discontinuous measurements are possible. In addition, methods using a TV camera with a shutter include placing a mechanical shutter in front of the TV camera, or using an electronic shutter f:
This method uses an image analysis device to take instantaneous images at higher speeds than ordinary television cameras, and then uses an image analysis device to count the number of particles on the screen.This method uses particle counting software and software. The drawbacks are that the hardware is expensive and the calculation time required for particle image analysis is long (10 seconds to several minutes), making continuous measurements impossible.

(Problem to be solved by the invention) Regarding understanding the situation of the combustion zone formed in front of the blast tuyere of a blast furnace, a luminance sensor is used to detect the coke particles and green ore particles that repeatedly fall and swirl within the raceway. By accurately capturing the number of pieces and performing continuous measurements, we can improve the accuracy of raceway information. It is an object of the invention to improve this.

Means for Solving Problem C) This invention detects the state of the combustion zone formed in front of the blast tuyere of a blast furnace through the tuyere viewing window, and detects the size of the field of view at the observation position of the combustion zone. is approximately less than 15φ seaweed,
The state of the combustion zone can be determined by using a luminance sensor whose response speed to changes in light is less than 1 ms, and by counting the number of instantaneous drops in the output signal within a certain period of time among the output signals measured by this luminance sensor. To detect? Features. This is a method for detecting the combustion zone in front of the blast tuyere of a blast furnace.

This invention? This will be explained according to FIG. In the figure, l is a blast furnace body, 2 is a blower branch pipe, 8 is a tuyere viewing window, and a brightness sensor 4 is installed immediately after the tuyere viewing window 3. 5 is an amplifier, 6 is a particle counting device, 7 is a display device, 8 is a visual field of a brightness sensor, 9 is a tuyere, 10 is coke, raw ore particles, and 11 is a raceway.

Does the brightness sensor 4 (hereinafter simply referred to as the sensor) measure the brightness of raceway 11, which is burning at high temperatures? The coke/raw ore particles 10 (hereinafter simply referred to as particles) that are detected and converted into output signals or descend and swirl within the raceway 11 have a lower temperature than the raceway 11. The brightness is even lower than the brightness of way 11, and it appears black. Therefore, when the particle 10 enters the field of view 8 of the brightness sensor, the output signal of the sensor 4 decreases. Of this output signal, the instantaneous decrease in the output signal within a certain period of time (2) The sensor 41'i has conditions for more accurate measurement: (1) The size of the field of view at the observation position is 16φ or less ( 2) Experiments revealed that the response speed to light was 1 ms or less.

The reason for (1) is that the sensitivity of brightness detection is improved when the brightness is filled in a narrow field of view, compared to when it is measured in a wide field of view. Since the particle 10 usually has a diameter of 15 to 4011jl, the field of view 8 of the sensor is set to be less than 15φ.

The reason for (2) is that the particle velocity is 5 to 20 m/s and the speed is 1 m8 or less.

Specifically, these conditions can be realized by using an optical lens for (1) and by using a photon (solar cell) for (2).

Further, the output signal of the sensor 4 is amplified by an amplifier 10 and then input to a number counting device 6. Number counting 'E! ;! 11
6 is the number of particles 10 by counting the number of instantaneous drops in the output signal within the output signal at a certain time. Accurately capture the results and display them on the display device 12
Ru.

(Operation and Examples) The operation according to the structure (711) of this invention will be explained with reference to FIGS. 2 and 3 along with examples.

As shown in FIG. 1, the present invention measures the brightness of the raceway 11 in the furnace by a sensor 4 attached to the tuyere viewing window a attached to the blast branch pipe 2, and the output signal is measured by a particle meter VT table device. Count.

The output signal measured by the sensor 4 is one that measures the number of instantaneous drops in the output signal within a certain period of time among the output signals determined by θ1. As shown in FIG. 2, this output signal is measured by measuring Δ for T seconds at second intervals and stored in the particle counter @6.

Furthermore, the luminance of T-th shown in the figure is X(1) and x+1-1
1, and when a point appears where the sign of this difference ΔX(1) changes from negative to positive, the change from this eclipse to positive is counted as one particle. By performing this continuously, it is possible to count two particles within a unit time.

Once, the particle 10 in FIG.
By accurately detecting the number of drops in the output signal when passing through the IFs, it is possible to determine the number of particles The measured values are shown in Figure 3.The sensor 4 used uses a silicon element and has a response angle of 1 m.
Below, the field of view 8 of the sensor was set to lOφ■, and the particle counter 6 was measured at -tI7) intervals of 2 ms and fA constant time T (seconds).

As can be seen from the figure, the number of particles 1O decreases periodically at intervals of about 10 minutes, and this period roughly corresponds to the interval of charging raw materials to the blast furnace, making it useful for understanding the unloading situation in the lower part of the blast furnace. (Effects of the Invention) According to the present invention, stable blast furnace operation can be realized by appropriately measuring the brightness in the raceway to determine the condition of the combustion zone of the blast furnace.

[Brief explanation of drawings]

Figure 1 is a block diagram of # equipment used in this invention. Figure 2 is a graph showing the brightness change at T311Jl in front of the raceway tuyere. It is a graph that represents □

Claims (1)

[Claims] 1. When detecting the condition of the combustion zone formed in front of the blast furnace's blast tuyere through the tuyere viewing window, the size of the field of view at the observation position of the combustion zone is approximately 15φmm or less. The combustion zone can be determined by counting the number of instantaneous drops in the output signal within a certain period of time among the output signals measured by the brightness sensor, using a brightness sensor that has a response speed of more than 1 ms to changes in light. A method for detecting a combustion zone in front of a blowing tuyere of a blast furnace, characterized by detecting the situation.