KR200313608Y1 - Tuyer line clogging detection and purging device using thermocouple - Google Patents

Abstract

The present invention is able to immediately detect when the powdered line is installed between the distributor and tuyere that supplies pulverized coal and the powdered line that transfers the pulverized coal is blocked by pulverized coal. The apparatus relates to a conventional method of processing a transport pipe (or installing it outside the pipe) and installing a flowmeter, and detecting the blockage by the presence or absence of flow rate in the pipe when the pipe is blocked by pulverized coal (PC). Compared to the temperature change rate by using the principle that the temperature is lowered when the powder transport pipe is blocked by pulverized coal, it can be installed very simply without the processing of the tuyer line and using a reliable thermocouple. Highly pulverized coal injection by quickly and accurately detecting the blockage condition of the line to prevent any unsettled pipes from occurring. It will contribute to an ever-ups.

Description

Tuyer line clogging detection and purging device using thermocouple

The present invention relates to a blockage detection and purging device of a tuyer line using a thermocouple, and transports powder from the distributor to the blowhole in the pulverized coal blowing operation of the blast furnace operation that produces melting and molten iron using raw materials such as iron ore, sintered ore and coke. As the tuyerin line, which is a pipe, detects and penetrates it immediately when it is blocked by pulverized coal, which is a fluid in the pipe, the tuer line always blows pulverized coal and contributes to the pulverized coal blowing operation.

In the blast furnace operation that produces molten iron using raw materials such as iron ore, coke and sintered ore, the pulverized coal injection (PCI) process is a low-cost non-coking coal without a coke manufacturing process. It is a process that is blown through 34 tuyeres of blast furnace through milling in mill and drying, conveying and distributing.

During the pulverized coal injection (PCI) operation, 34 tuyer lines (3) of about 50M from the distributor (1) to the downhole blown lens (2) are blocked by the change in the conditions of the pulverized coal (humidity, particle size, and other operating conditions). At this time, an unblown tuyer line is generated.

In this case, the blast furnace operation with the goal of 180kg / TP high coal injection (PCI) (based on 4 blast furnaces, currently about 150Kg / TP injection) since 1998 has a problem, which affects the operation of high coal injection (PCI). Get mad.

During normal pulverized coal injection (PCI) operation, the temperature of the tuyer line (3) is maintained in the range of about 40 ~ 65 ℃, when clogging is lowered with a constant temperature drop rate, the present invention uses the tuyer line ( In order to contribute to high pulverized coal injection (PCI) operation in the operation of blast furnaces by taking the following measures such as detecting the blockage condition of 3) quickly, providing information on it, and purging through the air line (4).

Methods known to date to detect when the tuyer line is clogged include, firstly, by differential pressure (ΔP), which is the upper pressure (distributor side, P1) and the lower side from the blockage point when the tuyer line is blocked. Detects the blocked state by the difference of pressure (ventilation side, P2) (△ P = P1-P2), which requires modification of the tuyer line, length of the pressure extraction line, and problems in detection. There is a problem to dismantle the pipe during maintenance.

Second, the junction is cold junction (T1) and the junction of the hot junction (T2) is a hot junction (T2) to join the different metals at these two points and then the temperature difference between the two points (△ T = T1-T2) It uses the Seebeck Effect, which has a long response time, requires special management for inspection and management, and needs to consider the characteristics of 34 pipes individually. There is a disadvantage that can be determined.

Third, it is a method by a solid flowmeter, which is a method of directly measuring the flow rate of powder (pulverized coal) attached to the pipe to determine the blocked state, which is not only expensive but also the measured value is the temperature of the powder in the pipe. There is a disadvantage that it is affected by the powder component.

In addition, there is a method to prevent clogging by periodically purging one line for each of the 34 tuyeres in the pulverized coal injection, but there is always one unblended line, and the purging is continued even for the unblocked pipe. This will result in waste of utility (compressed air) and shorten equipment life.

Therefore, the present invention was devised to solve the above-mentioned problems, and the thermocouple was installed in the tuyer line to continuously detect the temperature value detected through the algorithm, so that the clogging state of the tuyer line can be detected quickly and purging is possible. It is an object of the present invention to provide a blockage detection and purging apparatus of the tuyer line.

1 is a system and system configuration of the tuyer line associated with the present invention.

Figure 2A is a structural diagram of the thermocouple used in the present invention.

2B is a thermoelectric characteristic diagram of a thermocouple used in the present invention.

Figure 3 is a block diagram of a data collection system for the present invention.

FIG. 4A is a graph showing temperature data measured from the data collection system of FIG. 3;

FIG. 4B is a graph showing temperature data measured from the data collection system of FIG. 3 when a line is clogged and a change in temperature of the tutor line. FIG.

5 is a flow chart for the blockage detection of the present invention.

6 is a sequence diagram showing a blockage detection and purging sequence thereof of the present invention.

<Description of the symbols for the main parts of the drawings>

1: Splitter 2: Blown Lance

3: tuyer line 4: air line

5: thermocouple 6: compensation lead

7: thermocouple converter 8: processor

9: relay 10: three-way valve

11: thermocouple fixing device 12: terminal box

13: personal computer 14: A / D converter

15: Power Supply & Signal Converter

Tuyer line clogging detection and purging device of the present invention for achieving the above object is a thermocouple for measuring the temperature by measuring the thermoelectric power according to the temperature change of the tuyer line,

A compensation wire for transmitting the thermoelectric power generated by the thermocouple,

A thermocouple converter for converting the thermoelectric power transmitted through the compensation wire to the standard signal level,

A processor equipped with a blockage detection algorithm that periodically samples the standard analog signal of the thermocouple converter and quickly detects the blockage when the blockage occurs;

A relay receiving the digital signal of the processor and outputting a contact signal;

If it is determined by the contact signal of the relay that the tuyer line is stuck by the pulverized coal and determined to be blocked by the processor, the relay passes through the processor after a certain period of time after the air purging by switching the current and blown modes to the purging mode. If it is determined that the switch to the blown mode again characterized in that it comprises a three-way valve for performing the normal pulverized coal blowing operation.

The above and other objects and features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

The construction of the present invention is a thermocouple (5), a compensation wire (6), a thermocouple converter (7), a processor (8), a relay (9) and a purging three-way valve installed in the tuyer line (3) as shown in FIG. It consists of (10).

Thermocouple (5) is a sensor that detects the temperature by measuring the thermal power (mV) according to the temperature change of the tuyer line, the thermocouple used in the present invention is excellent in the linearity of the thermal power and used in a wide temperature range It was possible (0 to 1050 ° C.), and the K-Type and Sheath thermocouples 5 were used because the wire diameter was thin and excellent in response and workability. Installation was performed in conjunction with the thermocouple support fixing device 11 at the bottom 15M of the distributor (1).

The compensating wire 6 is a signal cable for transmitting the thermoelectric power generated from the thermocouple 5 to the converter 7, and a general ordinary compensation wire for K-type having good thermoelectric power transmission characteristics (KX-G) is used.

The converter 7 is a very weak signal of several mV transmitted through the compensating lead 6, so that the converter 7 converts the signal into a signal level of 1 to 5 V, which is a standard signal. (7) was used.

The processor 8 is equipped with a blockage detection algorithm for the present invention, and periodically samples the signals from each thermocouple installed in 34 tuyer lines, and then quickly blocks the blockage. It is a system to detect.

The relay 9 is for receiving the digital signal from the processor 8 and outputting the contact signal (on, off) to the three-way valve 10.

When the three-way valve 10 determines that the tuyer line 3 is fixed by pulverized coal and blocked by the processor 8, the relay 9 switches the current injection mode to the purging mode by the relay 9. After switching to perform air purging and determining that the processor 8 has penetrated after a predetermined time, it is switched to the blowing mode again to perform normal pulverized coal blowing operation.

After the installation of 12 thermoelectric thermometers (5) in the tuyer line (3) for the present invention, the data collection system was configured, and the data was collected and analyzed. The system includes a personal computer (13) for data collection and processing, A / D converter 14 for converting analog signals to digital signals, and a power supply and a signal converter 15.

Figure 2A is a structural diagram of the thermocouple used in the present invention, excellent linearity of thermoelectric power and can be used in a wide range of temperature (0 ~ 1050 ℃), thin wire diameter K-Type excellent in response and workability Sheath (Sheath) thermocouple (5) was used.

According to the specification, the total length is 7750 (m), the conductor is 2-wire, the material is SUS 316, and the outer diameter is 3.2 mm.

2B is a thermoelectric characteristic diagram of a thermocouple used in the present invention, and it can be seen that the thermoelectric power increases with an increase in temperature.

Figure 3 is a block diagram of the data acquisition system for the present invention, when the thermocouple is installed in the tuyer line is blocked the tuyer line is blocked, the temperature of the line has a constant rate of change while the personal computer algorithm to continuously detect the detected temperature value The blockage of the tuyer line can be detected quickly by showing on the monitor.

4A and 4B show the temperature change characteristics of the tuyer line obtained from this system (only some four of the 34 lines are shown).

That is, as shown in FIG. 4A, the temperature characteristics of the 34 tuyerine lines 3 change with correlation during normal pulverized coal injection. When one of the lines is blocked, the line falls at a constant temperature as shown in FIG. 4B. Found to change with characteristics.

Referring to FIG. 1, the present invention applying the characteristics of the temperature change is first transmitted through the compensating wire 6 from a total of 34 thermocouples 5 installed in each of the 34 tuyer lines 3. The signal is then interfaced to the processor 8 via a thermocouple converter 7. In the processor 8, 34 temperature values are sampled in units of 15 seconds. In general, in the case of temperature, the sampling period is 10 to 20 seconds, and in the present invention, the intermediate value of 15 seconds is used.

The sampled temperature data is judged as the normal or clogging of the tuyer line 3 by the detection algorithm manufactured for the present invention. Compared to the method of judging abnormality (clogging) when going down, this algorithm uses a speed-type algorithm to immediately detect the blockage of the pipe and increase its coping response.

Also, by comparing the speeds (tilts) of the 34 temperature data, the blockage detection error was enhanced.

That is, the value of m, which is a criterion for blocking the tuyer line,

m = kdT / dt

k = Constant

T = Temperature [Temperature (℃)]

as t = Time (sec)]

The continuous temperature value from the thermocouple is sampled in the processor every 15 seconds, and then processed by the above algorithm to output a signal of the abnormality of the tuyer line as a signal, and this condition is set to the three-way valve driving mode (blow mode, purging mode). In doing so, the tuyer line 3 was effectively managed and contributed to the operation of high coal dust injection (PCI). The value of m for each line

(i = 1, 2, 3, ....... 34: Tuyer line number)

(j = 1, 2, 3, ....... 34: Sampling cycle)

When the change rate of a sample sampled from an arbitrary tutor line is m11, if this value is less than or equal to the set value, it is judged as a blockage of the tutor line (21), except for the remaining lines. Compared to the m-values of m21 (m21, m31 ... m341), even if the m11 value is below the setting value for the blocking judgment, it is determined to be in a steady state if it is within the tolerance range of these values (22).

That is, the final blocking condition of the tuyer line is Choked Up (23): {m11 / m11 <Set Value. AND. / m11> (m21, m31 ... m31) * W}

W can be expressed as Weight.

The blockage determination time of the tuyer line by this algorithm is 15 seconds, which is a sampling period, which can be said to be about 4 times faster in response than the lower temperature limit, and the purge three-way valve 10 is opened immediately. The tuyer line can be penetrated immediately.

Figure 5 is a flow chart (Flow Chart) for this process, if it is determined that the blockage of the final tuyer line is changed from the normal mode to the purging mode by the three-way valve mode change (24), thereby purging the tuyer line This is done. At this time, the operation is completed when the purging is completed by determining whether the tuyer line is purged (25). However, if the blockage in the pipe is continued even though the blockage in the pipe is continued by the purging mode, the pipe is fixed after dismantling. After removal it is reassembled (26).

Here, ml of (22) is each m value of 33 tuyer lines except mij.

6 is a blockage detection and purging sequence diagram of the present invention, which shows a temperature change curve in a normal blowing mode up to 75sec. At this time, the three-phase valve state is in the blown mode. Between 75sec and 120sec, the tuyer line is blocked and the temperature drops drastically. Therefore, the air purge mode is switched from the blown mode.

As described above, the present invention provides a thermocouple installed in the tuyer line, which is a powder transport pipe, and continuously applies the detected temperature value through an algorithm, thereby quickly detecting and purging the blockage state of the tuyer line, and also the powder transport pipe. Compared with the conventional method such as detecting the blocked state by the presence or absence of the flow rate in the pipe by installing the tool, it can be installed more simply without the processing of the tuyer line, and it is detected by the thermoelectric thermometer, so it is highly reliable, the response time is fast and the cost is high. It has the effect of saving.

Preferred embodiments of the present invention are for the purpose of illustration and various modifications, changes, substitutions and additions will be possible to those skilled in the art through the spirit and scope of the present invention as set forth in the appended claims.

Claims (1)

In the pulverized coal injection apparatus of blast furnace industry which produces melting and molten iron using raw materials, such as iron ore, sintered ore, and coke, A thermocouple installed at a predetermined point at the lower end of the distributor when the tuyer line from the distributor to the tuyere is blocked by pulverization of pulverized coal, which is a fluid in the pipe, and measuring the thermoelectric power according to the temperature change of the tuyer line to detect the temperature; A compensation lead for transmitting the thermoelectric power generated by the thermocouple; A thermocouple converter for converting the thermoelectric power transmitted through the compensation lead to a standard signal level; A processor equipped with a blockage detection algorithm that periodically samples the standard analog signal of the thermocouple converter and quickly detects the blockage when the blockage occurs; A relay for receiving a digital signal of the processor and outputting a contact signal; When it is determined by the contact signal of the relay that the tuyer line is stuck by the pulverized coal and blocked by the processor, the relay switches the current blowing mode to the purging mode and performs air purging after a predetermined time. Tuyer line clogging detection and purging device characterized in that it comprises a three-way valve to switch back to the blown mode and perform a normal pulverized coal blowing operation when it is determined that the processor has penetrated.