KR940009666B1 - Temperature revision method of thermo-couple - Google Patents

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Description

Thermocouple Temperature Correction Method

1 is a cross-sectional view of a bottom portion showing a general thermocouple arrangement

2 is a concentric circle showing a general thermocouple arrangement

3 is a temperature correction flow chart of the bottom thermocouple according to the present invention

4a, b, c and d are graphs of correction temperature graphs of the bottom-bottom thermocouple in each case according to the present invention;

5a, b, c and d are comparisons between the measured temperature and the measured temperature of the 4a, b, c and d degrees.

* Explanation of symbols for main parts of the drawings

1, 3: thermocouple 2: firebrick

The present invention relates to a method for estimating the remaining thickness with the bottom edge and the thickness of the reinforced layer using the measured temperature of the thermocouple embedded in the bottom of the blast furnace, in particular the temperature of the thermocouple short-circuited in the short circuit of the thermocouple embedded in the bottom The present invention relates to a method for estimating the remaining thickness with the bottom edge and the thickness of the solidified layer.

In general, in the blast furnace bottom part, which is composed of carbide batters for refractory bricks, the molten iron produced in the blast furnace industry and slag, a by-product, exist at a high temperature. As a result, the lead is eroded by the molten iron and the remaining thickness of the lead becomes thin. And the solidification layer is formed on the remaining edge due to heat fluctuations inside the blast furnace. Therefore, in actual blast furnace operations, it is necessary to always predict and measure the thickness of the residual lead and the thickness of the solidification layer.

On the other hand, the thermocouple 1 of the bottom wall part is uniformly arranged in the circumferential direction as shown in FIG. 1 and inserted 100-200 mm into the refractory brick 2, and the thermocouple 3 of the bottom bottom part has a height. It is inserted for each of the circumferential direction and the radial direction at the position of three stages in the direction. The thermal states of the bottom edge and the bottom portion are managed based on the temperatures of the thermocouples 1 and 3 arranged in this way. However, when the thermocouple is short-circuited, the thermocouple 1 installed in the bottom wall can be repaired, but the thermocouple 3 installed in the bottom of the bottom can not be replaced.

Conventionally, there is a one-dimensional method disclosed in Japanese Laid-Open Patent Publication No. 56-163207 as a method for estimating the remaining edge and thickness of the blast furnace bottom and the solidification layer thickness. Since this method basically uses a thermocouple temperature unit embedded in the furnace, when an abnormality of thermocouple information occurs due to a short circuit of the thermocouple, it cannot be used anymore.

In addition to estimating the duct and residual thickness of the blast furnace bottom and the solidification layer thickness through two-dimensional thermal conductivity analysis, a method of correcting the temperature as an ambient thermocouple when the thermocouple is short-circuited has been proposed. This method is divided into three types of thermocouple short circuits, using the temperature immediately before the short circuit as the temperature at the shorted point, using two adjacent thermocouple temperature values as the temperature at the shorted point, or two adjacent thermocouple temperatures. Using the values, a method of using the average value as the temperature of the shorted point is presented. However, the first two of these methods are impractical, and the last method is to set the temperature of the shorted thermocouples by summing the two thermocouple temperature values in half regardless of the distance between the shorted thermocouples and two neighboring thermocouples. There was a problem.

In order to solve the above problems, the present invention derives the correlation between thermocouples and corrects the temperature of the shorted thermocouples on the basis of the above, thereby stably managing the nodule by estimating the exact remaining lead and thickness and the thickness of the solidification layer even when the thermocouples are shorted. The purpose of the present invention is to provide a thermocouple temperature compensation method for the furnace bottom.

The present invention provides a method for correcting the temperature of a thermocouple shorted at the time of a short circuit of the thermocouple installed in the blast furnace furnace in order to achieve the above object, the thermocouple from the measured temperature information of a plurality of thermocouples installed in the furnace blast furnace Determining whether the first thermocouple is short-circuited among the plurality of thermocouples, and calculating a non-short-circuit adjacent thermocouple having a minimum distance from the shorted first thermocouple, and determining the short-circuit adjacent thermocouple and the short circuit. Firstly deriving a temperature correlation between the first thermocouple and the non-short-circuit adjacent thermocouple from temperature information immediately before the short circuit of the first thermocouple, and correcting a temperature of the first thermocouple shorted by the correlation. Characterized in that.

Hereinafter, the present invention will be described in detail with reference to the drawings.

Referring to FIG. 3, first, it is determined whether a plurality of thermocouples are short-circuited, and if any of the thermocouples are short-circuited, the coordinate values of the x-axis, the y-axis, and the z-axis indicating the positions of all the thermocouples are input, respectively. . On the contrary, after inputting all the thermocouples in advance, it is possible to determine whether a plurality of thermocouples are short-circuited. Evaluate the distance between the shorted thermocouple and all other thermocouples, select the thermocouple with the minimum distance as the adjacent thermocouple, check if the selected thermocouple is short-circuit, and if this thermocouple is short-circuited, find the next close thermocouple. Select the adjacent thermocouple and repeat the process to check whether the thermocouple is shorted. Through this process, the shorted thermocouple and the closest uncoupled thermocouple among the unshorted thermocouples are found and the thermocouple is selected as an adjacent thermocouple. When adjacent thermocouples are selected, the correlation between shorted thermocouples and adjacent non-shorted thermocouples is analyzed and their correlations are obtained. From this correlation, the temperature of the shorted thermocouples is estimated based on the temperatures of adjacent thermocouples. The estimated shorted thermocouple temperature is then used to estimate the thickness of the remaining duct and solidification layer.

In order to refer to this in more detail compared to the conventional method is as follows. The numerical values used for explanation here are based on the temperature value of the thermocouple installed in the furnace blast furnace in operation, and the short-circuit time and the short-circuit position were arbitrarily selected.

First, thermocouples (A), (B), (C) and (D) are arranged on concentric circles of the same interval shown in FIG. Here, when the thermocouple B of the bottom part is short-circuited, the temperature of the thermocouple B is corrected as follows.

First, assuming (case 1) that the thermocouples (A) and (C) are not shorted, it can be seen that the thermocouple (A) is the closest uncoupled thermocouple of the shorted thermocouple (B). Therefore, the temperature correlation between the measured thermocouples (A) and (B) over a long period of time appears as shown in equation (1).

T (B) = 1.44T (A) -152.0... … … … … … … … … … … … … … … … … … … … (One)

However, T (A) and T (B) are the temperature (° C) of the thermocouple A and the thermocouple B, respectively.

As shown in FIG. 4A, when the temperature of thermocouples (A), (B), and (C) is recorded according to the number of operating days, respectively, the thermocouple (B) is short-circuited when the operating days are 70 days, for example. After the time point at which the thermocouple B is short-circuited, the measured temperature of the thermocouple B is not recorded, but the corrected temperature of the thermocouple B is recorded. That is, after the short-circuit of the thermocouple (B), the temperature of the thermocouple (B) is corrected by the equation (1), and appears as a dotted line, while according to the conventional method, the average temperature value of the thermocouples (A), (C) It is corrected and appears as a dashed line.

Second, when any one of the thermocouples (A) and (C) is short-circuited, the temperature of the thermocouple (B) is corrected as follows. First, assuming that the thermocouple A is confirmed to be shorted (case 2), it can be seen that the thermocouple C is the closest uncoupled thermocouple of the shorted thermocouple B. Therefore, looking at the temperature correlation between the measured thermocouples (B), (C) over a long period of time appears as shown in equation (2).

T (B) = 1.741 T (C) +57.1... … … … … … … … … … … … … … … … … … (2)

However, T (B) and T (C) are the temperature (° C) of the thermocouple B and the thermocouple C, respectively.

As shown in FIG. 4B, when the temperature of thermocouples (A), (B), and (C) is recorded according to the number of operating days, respectively, the thermocouple (B) is short-circuited when the operating days become 70 days, for example. After the time point at which the thermocouple B is short-circuited, the measured temperature of the thermocouple B is not recorded, but the corrected temperature of the thermocouple B is recorded.

That is, after the short-circuit of the thermocouple (B), the temperature of the thermocouple (B) is corrected by the equation (2) and appears as a dotted line, while according to the conventional method, the measured temperature of the thermocouple (C) is the temperature of the thermocouple (B) It is corrected to appear as a dashed line.

On the other hand, assuming that the thermocouple C is short-circuited (case 3), as shown in FIG. 4C, the temperatures of the thermocouples A, B, and C are respectively varied depending on the number of working days. If the thermocouple (B) is short-circuited, for example, on the 70th day of operation, the measured temperature of the thermocouple (B) is not recorded after the time point at which the thermocouple (B) is short-circuited, but the corrected temperature of the thermocouple (B). Is recorded.

That is, after the short-circuit of the thermocouple B, the correction temperature of the thermocouple B is represented by a dotted line corrected by the equation (1), while according to the conventional method, the measured temperature of the thermocouple A is the thermocouple B. It is corrected to the temperature of and appears as a dashed line. Third, when both the thermocouples A and C are shorted (case 4), the temperature of the thermocouple B is corrected as follows. Here, it can be seen that the thermocouple D is an adjacent thermocouple that is not shorted. Therefore, looking at the temperature correlation between the thermocouples (B), (D) measured over a long period of time, it appears as shown in equation (3).

T (B) = 1.483 T (D) -75.9... … … … … … … … … … … … … … … … (3)

However, T (B) and T (D) are temperatures (° C.) in the thermocouple B and the thermocouple D, respectively.

As shown in FIG. 4D, when the temperature of thermocouples (A), (B), and (C) is recorded according to the number of operating days, respectively, the thermocouple (B) is short-circuited when the operating days become 70 days, for example. After the time point at which the thermocouple B is short-circuited, the measured temperature of the thermocouple B is not recorded, but the corrected temperature of the thermocouple B is recorded.

That is, after the short-circuit of the thermocouple B, the correction temperature of the thermocouple B is corrected by equation (3) and appears as a dotted line, whereas according to the conventional method, the measured temperature just before the short-circuit of the thermocouple B is a thermocouple. It is corrected to the temperature of (B) and appears as a dashed line.

On the other hand, when comparing the temperature of the thermocouple B corrected for the case 1, case 2, case 3 and case 4 and the measured temperature of the thermocouple B in FIGS. 5a, b, c and d, The correction temperature of the thermocouple (B) according to the invention is almost concentrated on a straight line with a slope of 1 with respect to the measured temperature of the thermocouple (B), while the correction temperature of the thermocouple (B) by the conventional method is thermocouple (B). It can be seen that the concentration is hardly concentrated on a straight line with a slope of 1 with respect to the measured temperature of.

Therefore, in the present invention, when the thermocouples installed in the bottom of the bottom and the bottom wall are shorted, the thickness of the remaining edge and the thickness of the solidification layer can be accurately corrected by the temperature correlation with the uncoupled thermocouple. There is an effect that can be estimated.

Claims (1)

A method of correcting the temperature of a thermocouple at the time of a short circuit of a thermocouple installed in a blast furnace bottom part, the method comprising the steps of: determining whether the thermocouple is short-circuited from the measured temperature information of a plurality of thermocouples installed at the blast furnace bottom part and inputting a position; Calculating a non-short-circuit adjacent thermocouple having a minimum distance from the shorted first thermocouple when it is determined that the first thermocouple in the thermocouple is short-circuited; Deriving the temperature correlation between the first thermocouple and the non-short-circuit adjacent thermocouple in a first order, and correcting the temperature of the first thermocouple shorted by the correlation. Way.