TWI546140B - Method for measuring burning speed in sintering process - Google Patents

Description

Method for measuring the burning rate of a sintering process

The present invention relates to a method for measuring the burning rate of a sintering process, and more particularly to a method for measuring the vertical burning rate of a sintering raw material and determining the occurrence time of the burning point.

The sintering process is to sinter the fine iron ore into a lump ore as a raw material for iron making. Please refer to FIG. 1 for illustrating a schematic diagram of a conventional sintering process. First, the sintering raw material containing the fine iron ore, the flux, and the coke is compounded according to the requirements of the iron making, and the sintered raw material is placed in the trolley 30. Then, the trolley 30 is moved by the sintering machine 40, and the bellows 1-25 is provided below the moving path of the trolley 30. The trolley 30 is in the position of the bellows 1 to 2, and after the ignition cover 50 ignites the sintering raw material in the trolley 30, the sintering step is started. When the surface of the sintered raw material is ignited and passes through the bellows 1-25 to extract the air above the trolley and the combustion reaction is performed by the exhaust gas windmill 60, the position of the combustion zone in the sintering raw material gradually moves down as the sintering step progresses, and the combustion is completed. The exhaust gas is collected by the exhaust gas main pipe 70, and the electrostatic precipitator 80 is discharged after being dusted. The occurrence time of the burn-through point refers to the time during which the sintering raw material is sintered, and is often expressed by the position of the bellows corresponding to the sintering of the sintered raw material. The burning speed of the sintering process and the occurrence time of the burning point have an important influence on the quality of the finished product of the sintering raw material. The temperature distribution in the sintered raw material is the most specific reaction combustion condition. Evidence, but it is difficult to measure directly.

The conventional technology monitors the temperature of the bellows at the time of passing through the bellows, and then the temperature values of the measured bellows are approached by the quadratic curve method. Then, the obtained quadratic equation is used to estimate the time point at which the burn-through point occurs (corresponding to the position of the bellows), and then the on-site batching and sintering process is investigated according to the time point at which the burn-through point occurs. However, this prior art can only estimate the time point at which the burn-through point occurs (the position of the bellows), and it is impossible to know the moving speed of the combustion zone in the sintered raw material in the sintering process.

In view of the above, there is a need to provide a combustion rate measurement method which can be applied to a function of determining a time point at which a burn-through point occurs in a sintering process.

Therefore, one aspect of the present invention is to provide a method for measuring the burning rate of a sintering process by obtaining a vertical burning speed and a time point at which a burning point occurs, as a basis for the sintering process operation and control decision.

According to the above aspect of the invention, a method for measuring the burning rate of a sintering process is proposed, in which a sintering step is provided, wherein the sintering step is carried out on a sintering raw material loaded in a vehicle. Then, at a plurality of time points in the sintering step, a synchronous detecting step is performed to detect temperature information of one wall of the trolley, and a plurality of temperature profiles of each time point are obtained, wherein each temperature profile is obtained. The relationship between the wall height of the trolley and the wall temperature of the trolley is pointed out, and the synchronous detection step utilizes a non-contact temperature measurement method. Next, look for the high temperature position on the wall corresponding to the relative high temperature value and the relative high temperature value of each temperature profile. Then, a conversion step is performed to convert the above temperature profile into a high temperature position curve for each high temperature position for each time point. Then, a judging step is performed to determine that the high temperature position corresponding to the slope is the position of the sintering material relative to the burning point of the wall surface of the trolley when the absolute value of the slope of the high temperature position curve is less than or equal to the speed threshold value, and the slope is The corresponding time point is the time at which the burn-through point occurs.

According to an embodiment of the invention, the speed threshold is 0.01 meters/minute, 0.005 meters/minute or 0.003 meters/minute.

According to an embodiment of the present invention, the aforementioned sintering raw material includes fine iron ore, a flux, and coke.

According to an embodiment of the present invention, the non-contact temperature measuring method is performed by an infrared camera, wherein the infrared camera is disposed on the trolley and spaced apart from the wall surface of the trolley.

According to an embodiment of the invention, the measuring method further comprises: using a heat flow meter to correct the emissivity of the infrared camera.

According to an embodiment of the present invention, the non-contact temperature measurement method is performed by using a plurality of infrared cameras, wherein the infrared cameras are disposed along the moving path of the aforementioned trolley, and each infrared thermal image is provided. The instrument is separated from the aforementioned wall by the trolley.

According to an embodiment of the present invention, a plurality of bellows are disposed below the moving path of the trolley, and the trolley passes through the bellows at each time point.

Therefore, by applying the embodiment of the present invention, the non-contact temperature measurement method can be used to obtain the burning speed of the sintering raw material and the time point at which the burning point occurs, so as to operate and control the sintering process without affecting the sintering process. The main basis for decision making, thus achieving the goal of increasing production, improving quality and reducing economic costs.

1-25‧‧‧ bellows

30‧‧‧Trolley

31‧‧‧Infrared Thermal Imager

32‧‧‧ wall

40‧‧‧Sintering machine

50‧‧‧Igniter

60‧‧‧Sintered exhaust gas windmill

70‧‧‧Exhaust Gas Supervisor

80‧‧‧Electrostatic dust collector

200‧‧‧Sintering step

210‧‧‧Synchronization detection steps

220‧‧‧ Looking for relative high temperature and high temperature position

230‧‧‧Conversion steps

240‧‧‧Steps of judgment

D‧‧‧Distance

The above and other objects, features, advantages and embodiments of the present invention will become more <RTIgt;

2 is a flow chart showing a method of measuring the burning speed of a sintering process according to an embodiment of the present invention.

Figure 3 is a graph showing the temperature distribution of the wall of the trolley obtained at different points in time according to an embodiment of the present invention.

Figure 4 is a schematic diagram showing the configuration of a synchronization detecting step using an infrared camera according to an embodiment of the present invention.

Figure 5 is a diagram showing the relative high temperature distribution of the bellows number obtained for a wall height of the trolley according to an embodiment of the present invention.

Figure 6 is a graph showing the high temperature position curve obtained in accordance with an embodiment of the present invention.

The following examples are provided to illustrate the application of the present invention, and are not intended to limit the present invention, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention.

Referring to FIG. 1 and FIG. 2, FIG. 2 is a flow chart showing a method for measuring the burning speed of a sintering process according to an embodiment of the present invention. In the measuring method of the present embodiment, first, a sintering step 200 is provided in which the sintering step 200 is performed on the sintering raw material loaded in the trolley 30. In the present embodiment, the sintering raw material may include, for example, fine iron ore, a flux, and fine coke. The sintered raw materials are mixed and granulated in a mixing drum, and then placed in a trolley 30 of the sintering machine via a cloth system. The sintering machine used in this embodiment may have, for example, a bellows 1-25, and the height of the wall surface 32 of the trolley 30 may be, for example, 60 cm, and the fabric height may be approximately equal to the height of the wall surface 32 of the trolley 30. When the bellows 1 to 2 are ignited, the carriage 30 is moved to the rear end of the sintering machine at a speed of, for example, about 2.5 to 3.3 m/min to start the sintering step 200. The entire sintering step 200 takes about 30 minutes, wherein the operating conditions include: the pressure value measured by the bellows 1-25 is -1100~-1300 mm water column height, the single bellows flow rate is about 45000 m ³ /h, and the bellows is experienced. 1-25 Extract oxygen-containing air and carry out combustion reaction. The number of bellows used in the above sintering step 200, the specification of the trolley, the arrangement of the sintering raw materials, the ignition timing, and the sintering time are merely illustrative, and the embodiments of the present invention are not limited thereto.

Then, at a plurality of time points in the sintering step 200, a synchronization detecting step 210 is performed to detect the temperature information of the wall surface 32 of the trolley 30, and a plurality of temperature distribution maps at each time point are obtained. Each time point of the synchronization detecting step 210 may be, for example, a time point when the trolley 30 passes through each of the wind boxes 1-25, or a time point when the trolley 30 passes a plurality of preset positions on the moving path. Please refer to FIG. 3, which is a temperature distribution diagram of the wall surface 32 of the trolley 30 obtained at different time points according to an embodiment of the present invention, wherein the time points are the trolleys 30 passing through the bellows ( No.) 3-25 time point, each temperature profile indicates the wall of the trolley 30 The relationship between the height of 32 and the temperature of the wall 32 of the trolley 30. The device used in the synchronization detection step 210 will be described below.

Since the temperature of the sintering material in the sintering step 200 is very high, the temperature of the wall surface 32 of the trolley 30 is also relatively high. Therefore, the synchronization detecting step 210 must use a non-contact temperature measuring method. In the present embodiment, the non-contact temperature measurement method utilizes one or more infrared cameras to track the temperature of the wall surface 32 of the same vehicle 30. Before the temperature measurement, the infrared camera 31 needs to first correct the emissivity by the heat flow meter (the corrected emissivity is, for example, 0.75), and then input the corrected emissivity and the background temperature to improve the infrared thermal image. The accuracy of the instrument temperature measurement. Referring to FIG. 4, FIG. 4 is a schematic diagram showing the configuration of a synchronization detecting step using an infrared camera according to an embodiment of the present invention. In an embodiment, an infrared camera 31 is disposed on the trolley 30 on a tripod and separated from the wall surface 32 of the trolley 30 by a distance D (for example, 2 m), wherein the distance D is based on the wall to be tested. The area of 32 depends. When the area of the wall surface 32 to be tested is larger, the closer the infrared camera 31 is to the wall surface 32, that is, the smaller the distance D is. In another embodiment, a plurality of infrared cameras 31 are respectively disposed on the moving path of the carriage 30. For example, an infrared camera 31 is mounted at each of the bellows 25, and is separated from the wall surface 32 (i.e., the moving path) when the carriage 30 passes by a distance D. When the infrared radiation energy value measured by the infrared camera 31 is corrected by the environmental conditions and the emissivity settings input during the measurement, and converted into a temperature display, the temperature values are distributed in different colors via a color simulation technique. The display can convert all the energy values of the measurement points into a temperature-graded image, such as the temperature profile shown in Figure 3. As shown in Figure 3, as the bellows (number) 3-25 increases, The area of the red band representing the relatively high temperature gradually increases and moves toward the bottom of the trolley 30.

Next, step 220 is performed to find the high temperature position on the wall 32 corresponding to the relative high temperature value and the relatively high temperature value of each (windbox number) temperature profile. At this time, the relative high temperature value corresponding to each bellows number and the high temperature position (wall height) of the wall surface 32 can be integrated into a relatively high temperature distribution map, as shown in FIG. As shown in Fig. 5, the bellows (number) 3-25 is gradually increased to indicate the point in time at which the sintering process is carried out. As the sintering process progresses, the area of the relatively high temperature red band gradually increases and moves toward the bottom of the trolley 30. This phenomenon represents a phenomenon in which the temperature of the sintering raw material gradually increases from the top to the bottom as the sintering process proceeds. This embodiment seeks a relatively high temperature value and a high temperature position 220 by data analysis. Since the relatively high temperature value occurs from the wind box 6, the present embodiment can start from the wind box 6 to draw the relative high temperature value and high temperature position of each temperature distribution map.

Then, a conversion step 230 is performed to convert each temperature profile into a high temperature position curve for each high temperature position for each time point, wherein the time point refers to a time point in the sintering process. After obtaining the high temperature position on the wall surface 32 corresponding to the relative high temperature value and the relative high temperature value of each (windbox number) temperature profile, the data can be integrated into a high temperature position curve of the high temperature position to the time point, such as Figure 6 shows. As the sintering process proceeds, the relatively high temperature red band is gradually lowered in the height of the wall surface 32 of the carriage 30, so that a high temperature position curve having a negative slope is formed, wherein the absolute value of the slope represents the burning speed of the sintering step. In the present embodiment, the burning speed between the bellows 6-17 is 0.02 m/min, and the burning speed between the bellows 17-20 is 0.038 m/ Minutes, while the burning speed between the bellows 20-24 is 0.003 meters / minute. This result is consistent with the phenomenon that the burning speed varies with the progress of the sintering step due to the difference in gas permeability between the respective layers.

Then, a determining step 240 is performed to determine that the high temperature position corresponding to the slope is the position of the sintering material relative to the burning point of the wall surface of the trolley when the absolute value of the slope of the high temperature position curve is less than or equal to the speed threshold value, and the slope The corresponding time point is the time of occurrence of the burn-through point. In this embodiment, the speed threshold is 0.003 meters/minute. In other words, when the absolute value of the slope of the high temperature position curve is equal to or less than 0.003 m/min, the high temperature position corresponding to the slope is the position of the sintering material relative to the burning point A of the wall surface 32 of the trolley 30, and the slope corresponds to The time point is the time at which the burn-through point A occurs (the bellows 24), and the estimated burn-through point occurs at the same time as the result of the naked eye determination.

It can be seen from the above embodiments of the present invention that the invention has the advantages that the occurrence time of the burn-through point can be automatically estimated; the doubt that the occurrence time of the burn-through point is misjudged due to lack of experience can be avoided; the sintering process can be not affected Under the condition, the burning speed is measured and the occurrence time of the burning point is determined; the data of the burning speed and the burning time of the burning point can be obtained to adjust the subsequent processing conditions, thereby increasing the output, improving the quality and reducing the economic cost.

While the present invention has been described above by way of example, it is not intended to limit the invention, and the invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection of the present invention is subject to the scope of the patent application.

200‧‧‧Sintering step

210‧‧‧Synchronization detection steps

220‧‧‧ Looking for relative high temperature and high temperature position

230‧‧‧Conversion steps

240‧‧‧Steps of judgment

Claims (9)

A method for measuring a burning rate of a sintering process, comprising: providing a sintering step, wherein the sintering step is performed on a sintering raw material loaded in a vehicle, wherein the sintering raw material comprises a fine iron ore, a flux, and a coke And performing a synchronous detecting step at a plurality of time points during the sintering step to detect temperature information of a wall of the vehicle, and obtaining a plurality of temperature profiles of the time points, wherein each of the plurality of temperature profiles The temperature distribution map indicates the relationship between the wall height of the trolley and the wall temperature of the trolley. The synchronous detection step utilizes a non-contact temperature measurement method; searching for a relative high temperature value of each of the temperature profiles and the relative a high temperature position corresponding to the high temperature value on the wall surface; performing a conversion step of converting the temperature distribution map into a high temperature position curve of each high temperature position for each time point; and performing a determining step at the high temperature When one of the slopes of one of the position curves is less than or equal to a speed threshold, it is determined that the high temperature position corresponding to the slope is the sintering material. One of the wall of the carriage through the firing position of the point, the corresponding point of time is compared with the slope of the time of occurrence of burn through point. A method for measuring a burning rate of a sintering process as described in claim 1, wherein the speed threshold is 0.01 meters/minute. A method for measuring a burning rate of a sintering process as described in claim 1, wherein the speed threshold is 0.005 meters/minute. A method for measuring a burning rate of a sintering process as described in claim 1, wherein the speed threshold is 0.003 m/min. The method for measuring a burning rate of a sintering process according to claim 1, wherein the non-contact temperature measuring method is performed by using an infrared camera, and the infrared camera is disposed on the trolley and The walls are at a distance. The method for measuring the burning rate of the sintering process as described in claim 5, further comprising: using a heat flow meter to measure the emissivity correction of the infrared camera. The method for measuring a burning rate of a sintering process according to claim 1, wherein the non-contact temperature measuring method is performed by using a plurality of infrared cameras, and the infrared cameras are along the trolley. A moving path is set, and each of the infrared cameras is at a distance from the moving path. The method for measuring the burning rate of the sintering process as described in claim 7 further includes: using a heat flow meter to correct the emissivity of the infrared cameras. The method for measuring the burning speed of a sintering process according to claim 1, wherein a plurality of bellows are disposed below one of the moving paths of the trolley, and the trolley passes the bellows at the time points.