JPH03243705A - Method for controlling open/close of blender valve in blast furnace - Google Patents

Abstract

PURPOSE:To enable open/close of a bleeder valve without malfunction by providing many pressure measuring instruments in an RSE piping from the top of a blast furnace and making the highest measured value of the furnace as a top pressure signal. CONSTITUTION:Three or more pieces of the pressure measuring instruments are provided in the RSE piping from the top of blast furnace. When one of the pressure measuring value exceeds beta value, which is lower than the setting value +alpha, only one incomparators 1A - 1C is turned to 'ON' and AND circuits 2A - 2C and OR circuit 3A are left in ON as they are, the operational pressure setting value is transmitted to the bleeder valve control circuit. When two or more measured values exceed betavalue, a timer 5 is activated. In the case of continuing this condition for the fixed time, it is decided that the pressure is raised. Into bleeder valve control circuit, the signal of the highest value among the pressure measured values is transmitted to a selective switching circuit 7. In the selective switching circuit 7, the operational pressure measured value is switched to the above-mentioned highest pressure signal. By comparing this signal with the operational pressure setting value +alpha, the open/close of bleeder valve is controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to opening/closing control of a bleeder valve provided at the top of a blast furnace.

(Prior Art) During blast furnace operation, three valve stems (12A, 128. 12 C) is controlled to open and close by driving the hydraulic cylinder (13A, 138.13 C) via the control device (16>).The pressure that is the basis of this control is transmitted from the top of the blast furnace to the RES pipe line. 3 measuring devices (17
A17B.

11C), and a signal from one of these is used for control.

As mentioned above. Measuring device (+7 A, 178.17 G)
The in-furnace atrium detects the phenomenon, but since it exceeds the opening/closing control range of the RSE valve, which normally controls the in-furnace pressure, the bleeder valve is opened and the abnormal pressure is released into the atmosphere.

However, this opening/closing control is not a normal operation for opening the bleeder valve due to a sudden pressure increase due to internal blow-off, etc., and may occur if the pipe line at the detection end of the measuring device (17A, 17B, 17C) is clogged. The operation of opening the bleeder valve was frequently occurring due to erroneous signals due to malfunctions in the pressure detector, etc.

(Problem to be solved by the invention) In order to ensure stable blast furnace operation and protect blast furnace gas usage equipment, conventionally, one of the measured values of three pressure measuring devices installed in the pipeline from the furnace top to R5E If the operating pressure set value + α, it was considered an abnormality in the furnace and the bleeder valve was opened. However, if an abnormal value is measured, that is, if the pressure detection end is clogged, the bleeder valve may open due to an erroneous signal caused by other causes, which may worsen the furnace condition or cause the gas turbine of the top generator to open due to the abnormal pressure of the blast furnace gas. I was causing it to trip.

Therefore, we provide a control method that eliminates malfunctions of the bleeder valve due to erroneous signals and opens and closes the bleeder valve based on accurate pressure measurement values.

(Means for Solving the Problems) In view of the above-mentioned problems, the present invention contemplates that the R
Three or more pressure measurement devices are installed in the SE pipeline, and the first step is to measure the pressure with the measurement devices, and the operating pressure set value + α of the furnace top pressure control, which is the condition for opening the bleeder valve, is set. a second step and a value β lower than the operating pressure set value + α;
a third step of creating p, a fourth step of comparing said p with the measured value measured in the first step, and detecting abnormalities in two or more pressure measurement values based on the comparison data obtained in the fourth step. do! 5
a sixth step of monitoring whether the abnormality in the pressure measurement value continues; and a set value of the furnace top operating pressure control is set to the highest value among those measured by the pressure measuring device based on the sixth step. This invention provides a method for controlling the opening and closing of a blast furnace bleeder valve, which comprises opening and closing the bleeder valve through a seventh step of switching the value, an eighth step of comparing the operating pressure measurement signal 〇 and the seventh step, and the eighth step. be.

(Function) Pressure measuring devices are installed at three locations between the R5E pipe line installed from the top of the blast furnace to the scrubber, and the measured values at two or more locations are greater than the operating pressure measurement value 10 of the furnace top pressure control for a certain period of time. If it continues to be high, the highest measured value among the three measurements will be used as the furnace top pressure signal, and when this signal becomes higher than the operating pressure measurement value 10, which opens the bleeder valve, the bleeder valve will be opened. I opened it.

(Example) An embodiment of the present invention will be described based on the drawings.

When all the furnace top pressure measurements are normal values, there is no pressure measurement that exceeds the value of β, so the comparator circuit IAiB.

ICLtOFF becomes AND circuit 2 A, 2 B, 2
C and OR circuit 3A are both OFF, and timer 5 does not operate. Therefore, the operating pressure measurement value for furnace top pressure control is sent to the bleeder valve control circuit.

Next, the pressure measurement value of only one of the pressure measuring devices in the pipeline is β
When the value of is exceeded, the comparator circuits IA and IB.

The circuits 2A, 2B, 2C and the OR circuit 3A remain OFF, the timer 5 does not operate, and the operating pressure set value is sent to the bleeder control circuit. Also, the OR circuit is ON on the 3rd day.
Since N07 circuit 4 is also ON, ANDrj
Since J path 2D is turned ON, a pressure measurement value abnormality alarm signal is output.

Furthermore, if two or more pressure measurement values exceed the value of O, two or more of the comparison circuits IA, IB, and IC will turn ON, so AND circuits 2A, 2B, 2C and OR circuit 3A turns ON and the timer 5 starts operating. If this state continues for a certain period of time (10 seconds), it is determined that the pressure is actually rising, and one of the three pressure measurement values is sent to the bleeder valve control circuit. The highest value is selected by the high selector 6 and the signal of this highest value is sent to the switching selection circuit 7. In the switching selection circuit 7, the operating pressure measurement signal is switched to the selected maximum pressure signal, and this signal is compared with the operating pressure set value +0 to control the opening and closing of the bleeder valve.

Also, OR circuit 3B is turned on, but N07 circuit is turned off.
Therefore, the AND circuit 2D is turned off, and no pressure measurement value abnormality alarm signal is issued.

(Effect) Of the three pressure measuring devices installed in the pipeline from the top of the blast furnace to R5E that issue the signal to open the bleeder valve, two pressures exceed the set pressure in the furnace and the bleeder is closed. The bleeder valve was set to open if a value lower than 〇 in the operating pressure set value (setting value 〇-13), which is the opening signal, was obtained by the two measuring devices, and the pressure was the operating pressure set value + α, which caused the bleeder valve to open incorrectly. Since the bleeder valve is not activated by a signal, stable operation of the blast furnace can be achieved, resulting in energy-saving operation.

[Brief explanation of drawings]

FIG. 1 is a block diagram for explaining the present invention, and FIG. 2 is a diagram for explaining the outline of the blast furnace from the top to R5E. FIG. 3 is a conventional block diagram. I A, I B, I C, l D comparison circuit 2A,
2B, 2C, 2D ANO circuit 3 A, 3 B
OR circuit 4 NO
V circuit 5 Timer 6 Hey selector-7 switching selection circuit 8 A, 8 B Addition circuit +A, I I
B, I IC, 110 breeder T2A, 12B, 12
CRSE Benkeyaki 3A, l 38.13C hydraulic cylinder 14
Blast furnace body

Claims (1)

[Claims] The first step is to install three or more pressure measuring devices in the RSE pipeline from the top of the blast furnace and measure the pressure with the measuring devices, and the value of operating pressure set value + α for top pressure control, which is a condition for opening the bleeder valve. a second step of setting the operating pressure set value +
A third step of creating a value β lower than α, a fourth step of comparing said β with the measured value measured in the first step, and two or more pressure measurement values based on the data obtained in the fourth step. a fifth step of detecting an abnormality in the pressure measurement value; a sixth step of monitoring whether the abnormality in the pressure measurement value continues; and a set value of the furnace top operating pressure control based on the sixth step is determined by the pressure measurement device. Blast furnace bleeder valve opening/closing, which consists of a seventh step of switching the set value to the highest value among the measured values, an eighth step of comparing the operating pressure set value +α and the seventh step, and opening/closing the bleeder valve in the eighth step. Control method.