TW201331375A - Method for determining state of a blast furnace bed - Google Patents

Abstract

A method for determining a state of a furnace bed of a blast furnace is disclosed. In the method for determining the state o the blast furnace bed, at first, a temperature detecting device is used to detect temperatures at two positions in a wall of the blast furnace to obtain two temperature values of the wall, wherein the distance between a wall edge of the blast furnace and each of the two positions is different for the two positions, and the wall edge is the inner edge of the wall. Then, a temperature difference between the temperature values is calculated. Thereafter, a determination step for determining a state of the furnace bed is performed to use one of the temperature values and a variation trend of the temperature difference varied with the variation of the one of the temperature values to determine if an abnormal state of the furnace bed is caused, wherein the abnormal state is one of a state of gap existence, a state of over damage of the wall, and a state of dust over coating.

Description

Method for judging the condition of blast furnace hearth

The present disclosure relates to a method for judging the condition of a blast furnace hearth, and more particularly to a method for determining the condition of a blast furnace hearth by using the wall temperature.

Blast furnace smelting is a continuous production process that reduces iron ore to pig iron. Solid raw materials such as iron ore, coke and flux are fed into the blast furnace in batches from the top loading device according to the furnace conditions, and the dough surface is maintained at a certain height. Coke and ore form an alternating layered structure within the furnace. The ore material is gradually reduced, melted into iron and slag during the descending process, collected in the hearth, and discharged from the iron mouth and the slag port respectively.

In the process of blast furnace smelting, the blast furnace hearth and the bottom carbon brick will be gradually lost due to the action of the slag flow, chemical erosion and the like, thereby affecting the service life of the blast furnace. Therefore, the industry is committed to the development of monitoring technology for the condition of the hearth to reduce the chance of loss of the hearth. However, the current hearth condition monitoring technology not only requires complicated system equipment, but also often misjudgment, so a more accurate determination of the condition of the hearth is needed to reliably monitor the condition of the blast furnace hearth.

One aspect of the present invention is to provide a method for judging the condition of a blast furnace hearth for the blast furnace operator to monitor the condition of the blast furnace hearth and to take appropriate measures to avoid serious damage to the blast furnace hearth.

According to an embodiment of the present invention, in the method for determining the condition of the blast furnace hearth, firstly, the temperature detecting device is used to measure the temperature of the first furnace wall position and the second furnace wall position of the blast furnace to obtain the temperature of the second furnace wall. The value, wherein the distance between the first furnace wall position and the edge of the furnace wall is smaller than the distance between the second furnace wall position and the edge of the furnace wall, and the edge of the furnace wall is the inner wall edge of the blast furnace. Then, the wall temperature difference of the two furnace wall temperature values is calculated. Next, a hearth condition judging step is performed to determine whether an abnormal condition of the blast furnace hearth occurs by using one of the furnace wall temperature values and a temperature difference of the furnace wall temperature difference with respect to the temperature value of the furnace wall, wherein the abnormality occurs. The condition is one of the condition of the gap generation, the excessive wear of the furnace wall, and the excessive fouling of the furnace wall.

It can be seen from the above description that the method for determining the condition of the blast furnace hearth according to the embodiment of the present invention determines whether an abnormal condition of the blast furnace hearth occurs by using a change trend of the difference between the furnace wall temperature and the furnace wall temperature, and the blast furnace hearth condition of the embodiment of the present invention The judgment method can not only judge the residual thickness of the blast furnace hearth, but also judge the gap between the blast furnace wall tamping material and the scaling of the blast furnace wall, so that the blast furnace operator can truly understand the condition of the blast furnace hearth and take Proper treatment.

Please refer to FIG. 1 and FIG. 1A simultaneously. FIG. 1 is a schematic structural view of a blast furnace smelting system 100 according to an embodiment of the present invention, and FIG. 1A is a perspective view of the blast furnace body in the virtual frame of FIG. Schematic. The blast furnace smelting system 100 includes a blast furnace body 110, a temperature detecting device 120, and a computer system 130. The furnace wall of the blast furnace body 110 includes a metal outer casing 112, a tamping material 114, and a refractory material 116, wherein the tamping material 114 is disposed between the metal outer casing 112 and the refractory material 116. In the present embodiment, the material of the refractory material 116 may be a carbonized brick or a refractory clay brick, but the embodiment of the invention is not limited thereto.

The temperature detecting device 120 is disposed in the furnace wall of the hearth to measure the temperatures of points A and B in the refractory material 116 of the hearth wall of the hearth. In the embodiment of the present invention, the temperature detecting device 120 includes two thermocouples, which are respectively inserted into the positions of points A and B of the refractory material 116 to measure the temperature thereof. However, the embodiment of the present invention Not limited to this.

In Figure 1A, the distance between the position A and the edge E of the furnace wall (the inner edge of the blast furnace) is indicated by D1, and the distance between the position B and the edge E of the furnace wall (the inner edge of the blast furnace) is indicated by D2, and the distance is D1 is smaller than the distance D2. Further, in the present embodiment, the virtual straight line formed by the position A and the position B is perpendicular to the edge E of the furnace wall, but the embodiment of the present invention is not limited thereto.

The computer system 130 is electrically connected to the temperature detecting device 124 by wire or wireless to determine the condition of the blast furnace hearth by using the temperature values of the position A and the position B, and informs the blast furnace operator of the current state of the blast furnace hearth. In the present embodiment, the computer system 130 is a program-controlled computer of the blast furnace, but the embodiment of the present invention is not limited thereto.

Please refer to FIG. 2, which is a flow chart showing a method 200 for judging the condition of a blast furnace hearth according to an embodiment of the present invention. In the blast furnace hearth condition determination method 200, a temperature detecting step 210 is first performed to measure the temperature values of the furnace wall position A and the furnace wall position B by using the temperature detecting device 124 to obtain two furnace wall temperature values. TA and TB, wherein the temperature value TA represents the temperature value of the furnace wall position A, and the temperature value TB represents the temperature value TB of the furnace wall position B. Then, a temperature difference calculation step 220 is performed to calculate the difference between the temperature values of the two walls using the computer system 130. Next, the hearth condition determination step 230 is performed to determine whether the blast furnace hearth is abnormal by using the temperature value of one of the furnace wall position A and the furnace wall position B and the variation trend of the furnace wall temperature difference with respect to the temperature value. situation.

Please refer to FIG. 3 and FIG. 4 , FIG. 3 is a schematic flow chart of the hearth condition judging step 230 according to an embodiment of the present invention, and FIG. 4 is a diagram showing the condition of the hearth according to the embodiment of the present invention. A schematic diagram of the trend of the change in temperature value TB. In the hearth condition determination step 230, an index calculation step 232 is first performed to calculate a ratio of a difference between the furnace wall temperature and the furnace wall temperature value (for example, the temperature value TB of the furnace wall position B) to obtain a hearth condition. Indicator GI, where GI can be expressed as follows:

GI=TB/(TA-TB)

Next, a trend calculation step 234 is performed to calculate a change trend of the hearth condition index GI with respect to the temperature value TB. As shown in Fig. 3, if the current temperature state of the blast furnace is at the starting point O, when the temperature value TB is increased, the hearth condition indicator GI may increase or decrease with the temperature value TB, and form a trend curve Q1 or Q2. Similarly, when the temperature value TB decreases, the hearth condition indicator GI may increase or decrease with the temperature value TB and form a trend curve Q3 or Q4.

Then, a judging step 236 is performed to determine whether an abnormal condition of the blast furnace hearth occurs according to the change trend of the hearth condition indicator GI and the preset change threshold. For example, when the hearth condition indicator GI increases as the temperature value TB increases (trend curve Q1), and the change value of the hearth condition indicator GI exceeds a preset threshold, the tamping material 114 in the current blast furnace wall is judged. A gap occurs and this is an abnormal state. Therefore, a warning step 238a is issued to issue a warning message to inform the blast furnace operator that a gap has occurred in the tamping material 114, and the blast furnace operator can take appropriate measures accordingly.

For another example, when the hearth condition index GI decreases as the temperature value TB increases (trend curve Q2), and the change value of the hearth condition indicator GI exceeds a preset threshold, it is judged that the thickness of the current blast furnace wall is reduced (refractory Material 116 is excessively depleted), and this is an abnormal state. Therefore, a warning step 238b is issued to issue a warning message to inform the blast furnace operator that the thickness of the blast furnace wall is reduced, and the blast furnace operator can take appropriate treatment measures such as grout filling.

For another example, when the hearth condition indicator GI increases as the temperature value TB decreases (trend curve Q3), and the change value of the hearth condition indicator GI exceeds a preset threshold, it is judged that there are too many knots on the blast furnace wall. Scale, and this is an abnormal state. Therefore, a warning step 238c is issued to issue a warning message to inform the blast furnace operator that there is excessive scaling on the blast furnace wall, and the blast furnace operator can take appropriate measures accordingly.

In an embodiment of the invention, the change threshold corresponding to the hearth condition indicator GI may vary from trend to curve. For example, when the change trend curve of the hearth condition index GI is Q1, the hearth condition indicator GI may correspond to a preset change threshold, and when the change trend curve of the hearth condition indicator GI is Q2, the hearth condition indicator The GI can correspond to another preset change threshold, so that the method 260 of the blast furnace hearth condition of the embodiment of the present invention can more accurately determine whether the hearth has an abnormal condition.

In addition, when the hearth condition indicator GI is also likely to decrease as the temperature value TB decreases (trend curve Q4), this trend indicates that the blast furnace chiller is cooling the furnace wall. Since the opening of the chiller is normal operation, when the change trend of the hearth condition index GI is the curve Q4, it is not regarded as an abnormal state.

It should be noted that although the hearth condition index GI of the above embodiment is expressed by TB/(TA-TB), in other embodiments of the present invention, the hearth condition indicator GI can also be TA/(TA-TB). ), (TA-TB)/TB, etc., and when the representation of the hearth condition indicator GI is changed, the abnormal condition corresponding to each trend curve may also change, but any of the technical fields in the present invention have Generally, the knowledge person should be able to know the abnormal condition corresponding to each trend curve according to the above description.

In summary, the method for determining the condition of the blast furnace hearth according to the embodiment of the present invention establishes the hearth condition index GI, and uses the relationship between the hearth condition index GI and the temperature change of the blast furnace wall (the hearth wall) to judge the current furnace. Whether the bed has an abnormal condition. The computer system 130 of the embodiment of the present invention can also graph the change trend of the hearth condition index GI, and perform semi-quantitative analysis by the moving distance of the hearth condition indicator GI at each sampling point for the blast furnace operation. Personnel should take corrective measures to protect the blast furnace in a timely manner so that the service life of the blast furnace can be effectively extended.

While the invention has been described above in terms of several embodiments, it is not intended to limit the scope of the invention, and the invention may be practiced in various embodiments without departing from the spirit and scope of the invention. The scope of protection of the present invention is defined by the scope of the appended claims.

100. . . Blast furnace smelting system

110. . . Blast furnace body

112. . . metal shell

120. . . Temperature detecting device

130. . . computer system

114. . . Solid material

116. . . Refractory

200. . . Hearth condition judgment method

210. . . Temperature detection step

220. . . Temperature difference calculation step

230. . . Hearth condition judgment step

232. . . Indicator calculation step

234. . . Trend calculation step

236. . . Judgment step

238a~238c. . . Warning step

A, B. . . Temperature measurement point

D1, D2. . . Temperature measurement point distance

E. . . Furnace wall edge

Q1~Q4. . . Trend curve

The above and other objects, features, and advantages of the present invention will become more apparent and understood.

1 is a schematic view showing the structure of a blast furnace smelting system according to an embodiment of the present invention.

Fig. 1A is a schematic view showing the enlarged structure of the blast furnace body in the virtual frame of Fig. 1.

2 is a flow chart showing a method for judging the condition of a blast furnace hearth according to an embodiment of the present invention.

Fig. 3 is a flow chart showing the steps of determining the condition of the hearth according to the embodiment of the present invention.

Fig. 4 is a graph showing a curve of a change in the condition of the hearth relative to the temperature value according to an embodiment of the present invention.

200. . . Hearth condition judgment method

210. . . Temperature detection step

220. . . Temperature difference calculation step

230. . . Hearth condition judgment step

Claims (10)

A method for judging the condition of a blast furnace hearth, comprising: measuring a temperature of a first furnace wall position and a second furnace wall position of the blast furnace by using a temperature detecting device to obtain a temperature value of the second furnace wall, wherein the The distance between the position of a furnace wall and the edge of the furnace wall of the furnace wall is smaller than the distance between the position of the second furnace wall and the edge of the furnace wall, and the edge of the furnace wall is the inner wall edge of the blast furnace; calculating the temperature values of the furnace walls a difference in furnace wall temperature; and performing a hearth condition judging step to utilize one of the wall temperature values and a temperature difference of the furnace wall temperature difference relative to one of the furnace wall temperature values The value change trend is to determine whether an abnormal condition occurs in the blast furnace hearth, wherein the abnormal condition is one of a gap generation condition, a furnace wall excessive wear condition, and a furnace wall excessive scale condition. The method for judging the condition of a blast furnace hearth according to claim 1, wherein the furnace wall comprises a refractory material, and the first furnace wall position and the second furnace wall position are located in the refractory material. The method for judging the condition of a blast furnace hearth according to claim 2, wherein the furnace wall further comprises a tamping material and a metal outer casing, and the tamping material is located between the refractory material and the metal casing. The method for judging the condition of a blast furnace hearth according to the third aspect of the patent application, wherein the refractory material is a strontium carbide brick or a refractory clay brick. The method for judging the condition of a blast furnace hearth according to claim 3, wherein the determining the condition of the hearth condition comprises: calculating a ratio of a temperature difference between the furnace wall and one of the temperature values of the furnace walls to obtain a hearth condition indicator; a trend calculation step of calculating a change trend of the one of the hearth condition indicators relative to the furnace wall temperature values; and performing a determining step to determine according to the hearth condition indicator The indicator change trend and a change threshold determine whether the abnormal condition occurs in the blast furnace hearth. The method for judging the condition of a blast furnace hearth according to claim 5, wherein the judging step comprises: when the condition indicator of the hearth rises with the rise of the temperature values of the furnace walls, and the condition of the hearth When one of the indicators changes value is greater than the change threshold, it is determined that the abnormal condition occurs, and the abnormal condition is the gap occurrence condition, wherein the gap generation condition is a condition that the tamping material generates a gap. The method for judging the condition of a blast furnace hearth according to claim 5, wherein the judging step comprises: when the condition indicator of the hearth decreases with the rise of the temperature values of the furnace walls, and the condition of the hearth When one of the indicators changes value is greater than the change threshold, it is determined that the abnormal condition occurs, and the abnormal condition is an excessive wear condition of the furnace wall. The method for judging the condition of a blast furnace hearth according to claim 5, wherein the judging step comprises: when the condition of the hearth increases with the temperature of the furnace wall, and the condition of the hearth When one of the indicators changes value is greater than the change threshold, it is determined that the abnormal condition occurs, and the abnormal condition is an excessive fouling condition of the furnace wall. The method for judging the condition of a blast furnace hearth according to claim 1, wherein the one of the wall temperature values corresponds to the second furnace wall position. The method for judging the condition of a blast furnace hearth according to claim 1, wherein a virtual straight line formed by the first furnace wall position and the second furnace wall position is perpendicular to the edge of the furnace wall.