KR100971983B1 - Apparatus for controlling the pressure of feed hopper to prevent vent valve from being wearing, and controlling method the same - Google Patents

Abstract

The present invention relates to a hopper pressure control device and a control method for preventing wear of the back pressure control valve in the pulverized coal injection facility, and fully open the filling valve 41 and the back pressure control valve 103 of the feed hopper 40 and pressurizing the control valve ( 102 is closed, and the flow control valve 111 is opened to fill the pulverized coal with the feed hopper 40 from the pulverized coal storage tank 30; Completely closing the back pressure control valve (103), opening the pressure control valve (102), and continuously opening the flow control valve (111) to pressurize firstly; Continuously closing the back pressure control valve 103, closing the pressure control valve 102 again, and opening the flow control valve 111 to pressurize with flow nitrogen; The back pressure control valve 103 continues to be closed, the pressure control valve 102 is opened, the flow control valve 111 is continuously opened, and the secondary pressure is applied to the back pressure control valve 103 and the pressure control valve 102. Open the flow control valve 111 and continue to blow the pulverized coal into the blast furnace vent 60; Hopper for preventing the wear of the back pressure control valve in the pulverized coal injection facility, characterized in that the back pressure control valve 103 is opened, the pressure control valve 102 is closed again, and the flow control valve 111 is opened. Provided is a pressure control device and a control method thereof.

Pulverized coal injection equipment, feed hopper, back pressure control valve, two stage pressure, secondary pressure

Description

Hopper pressure control device and control method for back pressure control valve wear prevention in pulverized coal injection facility {APPARATUS FOR CONTROLLING THE PRESSURE OF FEED HOPPER TO PREVENT VENT VALVE FROM BEING WEARING, AND CONTROLLING METHOD THE SAME}

1 is a pressure control configuration diagram of a conventional fisheye facility

Figure 2 is a control valve and pressure change table according to the state of the conventional feed hopper blowing sequence

3 is a flow chart of a conventional feed hopper pressurization control

Figure 4 is a configuration diagram of the feed hopper pressure control device of the hopper pressure control method for preventing back pressure control valve wear in the pulverized coal injection facility according to the present invention;

5 is a control valve and pressure change table for each feed hopper blowing sequence state of the hopper pressure control method for preventing back pressure control valve wear in the pulverized coal injection facility according to the present invention;

Figure 6 is a flow chart according to the two-stage pressure control panel of the hopper pressure control method for preventing back pressure control valve wear in the pulverized coal injection facility according to the present invention;

7 is a two-stage pressure condition discrimination diagram of the hopper pressure control method for preventing back pressure control valve wear in the pulverized coal injection facility according to the present invention;

8 is a secondary pressure condition discrimination diagram of the hopper pressure control method for preventing back pressure control valve wear in the pulverized coal injection facility according to the present invention;

9 is a table of the secondary pressure control setting ratio according to the blowing amount of the hopper pressure control method for preventing wear of the back pressure control valve in the pulverized coal injection facility according to the present invention.

♠ Explanation of symbols for the main parts of the drawing ♠

30: pulverized coal storage tank 40: feed hopper 100: feed hopper pressure regulator

101: Hopper pressure controller setting signal selector 110: flow nitrogen flow controller

200: feed hopper operation mode selector 210: feed hopper sequence processing unit

300: measurement signal processor 400: two-stage pressure condition processor

420: secondary pressure condition processing unit 411: primary pressure ratio

412: Secondary pressure ratio 430: Two-stage pressure condition signal selector

The present invention relates to a hopper pressure control device and a control method for preventing wear of a back pressure control valve in a pulverized coal injection facility, and more specifically, a feed hopper is charged → pressurized → atmospheric → blown → back pressure in a PCI (Pulverized Coal Injection) injection facility. Hopper pressure for preventing wear of back pressure control valve in pulverized coal injection equipment to reduce the wear of back pressure control valve in the pressure control device of feed hopper 40 as a problem in feed hopper pressurization control during the process It relates to a control device and a control method.

As shown in FIG. 1, in the Pulverized Coal Injection (PCI) facility, when the pulverized coal pulverized in the grinder 10 is filled in the feed hopper 40 in the storage tank 30, the feed hopper 40 is supplied with nitrogen at a predetermined pressure. It is applied to the blown through the pipe connected from the lower portion of the feed hopper 40 to the tuyere 60 of the blast furnace 70 is blown.

In this process, it is very important to maintain a stable pressure of the feed hopper 40 for pulverized coal injection, and to control the pressure in the hopper 40 to pressurize nitrogen to the hopper 40 as a control valve for maintaining pressure. The back pressure control valve 103 and the flow control valve 111 for improving the flowability of the pulverized coal in the blowing process by preventing the pulverized coal from being fixed to the lower portion of the hopper 40 are described. Is the same as

1 is a feed hopper pressurization control of a pulverized coal injection plant having a facility for blowing pulverized coal to one reservoir 30, three feed hoppers 40, and a distribution valve 50 and a blast furnace 60 of the blast furnace 70. The configuration diagram is shown.

Referring to the process of controlling the pressure of the feed hopper 40 through this, the filling side 41 is installed between the reservoir 30 and the feed hopper 40, any one of three feed hopper 40 is When the filling process is performed, the fine coal of the storage tank 30 is filled with the feed hopper 40 which is the filling process, and when the upper limit of the weight of the feed hopper 40 is reached, the filling side 41 is closed, and at the same time the filling is completed. Pressurization is started by the flowchart of FIG. 3 to secure the pressure necessary for the feed hopper 40 blowing, and pressurizes when the pressure of the hopper 40 reaches the set pressure SV of the feed hopper 40. Exits into standby mode,

When blowing of the previous feed hopper 40 is completed, the blowing side 42 of the waiting feed hopper 40 is opened and the pulverized coal inside the hopper is pumped to the tuyere 60 of the blast furnace through the blowing side 42.                         

When the weight of the feed hopper 40 reaches the "Empty" setting value of the hopper, blowing is terminated and the residual pressure inside the hopper 40 is back-pressured through the back pressure control valve 103.

In addition, the lower portion of the feed hopper 40 is continuously supplied with a predetermined flow rate of the flowable nitrogen to prevent from being fixed to each other in the hopper of pulverized coal.

2 shows a valve and a pressure change state according to the mode of the feed hopper 40.

As shown in FIG. 2, after the pressurization is completed, the pressure of the hopper 40 is increased with the flowable nitrogen supplied to prevent the pulverized coal fluidity deterioration due to the coal dust sticking in the atmospheric state, and the back pressure control to control the pressure accordingly. The side 103 is open as much as the output signal of the pressure regulator 100 to continue to control, during this time the pulverized coal and high-pressure gas is mixed to pass through the control valve 103 at a high speed control valve 103 Frequent wear of the ball and the seat ring occurs inside, and wear and tear of the ball and the seat ring of the control valve 103 decreases the control characteristics of the control valve 103 and the control valve 103. The closing function is lost, and the pressure of the hopper is not kept constant, resulting in a poor control of the blown amount.

Referring to the valve wear strength due to the fine powder and nitrogen in the solid and gas two-phase flow of the control valve 103 as follows.

The impact applied to the valve ball and the seat ring by the minute powder when the fine powder and the solid nitrogen filled in the feed hopper 40 is discharged through the valve is proportional to the kinetic energy (Equation 1).                         

In other words, the discharge speed of the derivative twice as fast gives four times the impact (wear) in proportion to the square.

Kinetic energy (KE) = 1/2 × M × V² = Fd

To improve this, the conventional feed hopper pressure control method (Application No. 1999-31603) installs a small back pressure control valve and a large back pressure control valve to develop a time schedule for each valve. In addition, the control algorithm was developed and applied so that the flow rate bent in a certain time by using the operation characteristics of the valve to prevent the wear of the valve generated in the back pressure control time, but there are the following problems.

First, the pressure of the hopper is increased by the supply of liquid nitrogen in the blowing waiting time (the time when the feed hopper pressure is fully pressurized to the blowing pressure), which is the main wear factor of the back pressure control valve, and the discharged pressure is discharged to constant pressure. In order to maintain the back pressure control valve 103 to control the hopper pressure in the open state at a small angle, at this angle, the flow velocity of the control valve 103 is increased to give a sharp impact on the control valve 103, causing wear There is a problem coming.

Second, when abrasion of the back pressure control valve 103 occurs, nitrogen and pulverized coal in the feed hopper are discharged to the bag filter 20, which causes a problem that the pressure in the hopper is not kept constant.

Third, if the pressure in the hopper is not kept constant, there is a problem that it is impossible to control a constant blowing amount in the blowing process.                         

Fourth, there is a problem that it is impossible to maintain the furnace internal furnace and the furnace furnace blast if the injection amount is poorly controlled, and eventually the commercial production of water is impossible.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems in the prior art, and is a conventional continuous method of applying a pressurization method to fill the pressure for blowing pulverized coal through the distribution valve and the tuyere in the feed hopper after the filling of the feed hopper is completed. After the first pressurization in pressurization, pressurized by the flow nitrogen, the system recognizes the hopper's progress and determines the second pressurization time, and develops the second pressurization method to pressurize the second presser according to the decision. Wearing the back pressure control valve in the pulverized coal blowing facility that can stabilize the blowing amount control by eliminating unnecessary waiting time, which is the main wear factor of the valve, and allowing the process to proceed to the blowing state, which is the next process, to prevent wear of the control valve generated in the atmosphere. It is an object of the present invention to provide an anti-hopper pressure control device and a control method.

In order to achieve the above object, the present invention, in the apparatus for controlling the internal pressure of the feed hopper 40 in the pulverized coal injection facility, receives the weight information from the load cell 44 installed in the lower portion of the feed hopper 40 A hopper signal measurement processor (300) including a pressure measurement processor (310) for receiving and processing pressure information of the weighing calculation unit (320), the feed hopper (40), and the blast furnace opening (60); A sequence processor 210 which determines whether the filling condition, the blowing condition, the back pressure condition, the pressurization condition, etc. are satisfied according to the contact signal received from the hopper signal measuring processor 300; Logic for determining the primary pressure, the flow nitrogen pressure, the secondary pressure conditions according to the feed hopper 40 mode state and the pressure state of the feed hopper 40 from the hopper signal measurement processor 300, respectively A two-stage pressure condition processor 400; A secondary pressure condition processor 420 including logic for determining the secondary pressure condition according to the primary pressure and the flow nitrogen pressure in accordance with the determination condition of the second pressure condition processor 400; A primary pressure ratio 411 and a secondary pressure ratio 421 for pressurizing nitrogen according to conditions determined by the second stage pressure condition processor 400 and the secondary pressure condition processor 420; The two-stage pressure condition signal selector 430 for selecting the first and second pressure programs according to the two-stage pressure control signals of the primary pressure ratio 411 and the secondary pressure ratio 421 and the contact point outputted therefrom. A hopper operation mode selector 200 for selecting a control program according to a signal; Hopper pressure control device for preventing the back pressure control valve wear in the pulverized coal injection facility, characterized in that consisting of a hopper pressure control system setting signal selector 101 for controlling the hopper pressure control system 100 according to the signal of the hopper operation mode selector 200. To provide.

Meanwhile, the present invention completely opens the filling side 41 and the back pressure control side 103 of the feed hopper 40 using the control device configured as described above, closes the pressure control side 102, and controls the flow. Opening the side 111 to fill pulverized coal from the pulverized coal storage tank 30 with a feed hopper 40; When the pulverized coal filling is completed, completely closing the back pressure control valve (103), opening the pressure control valve (102), and continuously opening the flow control valve (111); When the primary pressurization is completed, continuously closing the back pressure control valve (103), closing the pressure control valve (102) again, and opening the flow control valve (111) to pressurize with fluid nitrogen; Continuing to close the back pressure control valve (103), open the pressure control valve (102), and continuously open the flow control valve (111) to pressurize the secondary nitrogen after the flow nitrogen pressurization is completed; When the secondary pressurization is completed, opening the back pressure control valve (103) and the pressure control valve (102), and continuously opening the flow control valve (111) to blow the pulverized coal into the blast furnace vent (60); When the pulverized coal injection is completed, the pulverized coal injection comprises a step of opening the back pressure control valve 103, closing the pressure control valve 102 again, and opening the flow control valve 111 to back pressure. The facility will provide a hopper pressure control method for preventing back pressure control valve wear.

In addition, in the present invention, the internal pressure of the feed hopper 40 is pressurized from 0 to 7 kg / cm 2 in the first pressurizing step, and the internal pressure of the feed hopper 40 is 7 to 11 kg / cm 2 in the pressurizing with fluid nitrogen. Pressurized by, and the secondary pressurizing step provides a hopper pressure control method for preventing back pressure control valve wear in the pulverized coal injection facility, characterized in that the internal pressure of the feed hopper 40 is pressed from 11 to 12kg / ㎠.

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

As shown in Figure 4, the hopper pressure control method for preventing the back pressure control valve wear in the pulverized coal injection facility according to the present invention is a hopper signal measurement processing unit 300, hopper sequence processing unit 210, two-stage pressure condition processing unit 400, The secondary pressure condition processing unit 420 and the first and second pressure ratio ratios (411,421), the signal selector (200, 430), the control system (100, 110) and control valves 102, 103, 111, etc., made of pulverized coal injection facility.

The hopper measurement signal processing unit 300 is composed of a pressure measurement processing unit 310 and the weighing operation unit 320, the pressure measurement processing unit 310 measures the pressure of the blast furnace 60 at the pressure of the hopper 40 And a two-stage pressure control signal according to the hopper pressure state, and the weight measuring unit 320 includes a load cell 44 installed at the lower portion of the feed hopper 40, and an input unit and a calculating unit which receive signals measured therefrom. It is.

The sequence processor 210 includes a condition processor 400 and 420 for determining whether the contact signal received from the hopper measurement signal processor 300 satisfies the filling condition, the blowing condition, the back pressure condition, the pressurization condition, and the like. It is.

The two-stage pressure condition processing unit 400 constituting the present invention determines the primary pressure, the flow nitrogen pressure, and the secondary pressure conditions according to three feed hopper mode states and the pressure states of the feed hopper 40. The secondary pressure condition processor 420 is configured with logic, and is configured with logic for determining the secondary pressure condition according to the progress state of the primary pressure and the flow nitrogen pressure.

The signal selector constituting the present invention selects a control program according to a contact signal and selector 200 for use as a remote setting signal of a pressure regulator and a selector for selecting a first and second pressure program according to a two-stage pressure control signal. 430.

According to the remote setting signal of each feed hopper 40, the output signal is generated according to the magnitude of the deviation compared to the pressure signal of the hopper, and the pressure regulator 100, the pressure control valve 102, the back pressure control valve 103 consist of.

In addition, there is a flow nitrogen flow control system 110 and the flow nitrogen flow control valve 111 to prevent the coal dust is fixed in the feed hopper 40 and to perform the flow nitrogen pressure function of the present invention.

Hereinafter, the operation of the present invention configured as described above in detail.

The pressure measurement processor 310 of the hopper measurement signal processor 300 receives a signal measured by the pressure transmitter 42 installed at the upper portion of the feed hopper 40, so that the pressure condition setter in the pressure measurement processor 310 is not shown. By comparing with the set value, it generates a contact signal that can determine the completion of the primary and secondary pressure.

The gravimetric calculation unit 320 receives the signal from the load cell 44 and calculates the fine pulverized coal weight value obtained by calculating the pure pulverized coal weight excluding the weight of the hopper by comparing with the weight condition setter and completing the filling and filling of the hopper being filled. A contact signal is generated to determine the completion of injection.

In addition, the sequence processor 210 generates a mode selection signal for filling, pressing, blowing, and backing pressure of each hopper according to a predetermined hopper mode and a contact signal of the hopper measurement signal processing unit 300.

Meanwhile, as shown in FIG. 7, the two-stage pressure condition processor 400 checks whether the three feed hoppers 40 are in normal operation, a control mode, a pulverized coal stock, and a feed hopper designation condition. If this is satisfied, the mode selector is selected as the pressure mode by the condition processor 400. When the pressure condition is established, the pressure regulator 100 of the hopper is controlled by the sequence processor 210. ) Is switched from manual (MAN) to remote (REM), the feed hopper 40 is also selected as a two-stage pressure mode (Mode).

In addition, when the primary pressure is activated, the signal is gradually increased by the ratio of the primary pressure, and if the output signal of the proportioner is equal to or larger than the preset primary pressure completion signal (ST1K), the output of the proportioner output signal is increased. The increase is stopped, and this output signal becomes the set value of the pressure regulator 100 via the two-stage pressure condition signal selector 430, the feed hopper operation mode selector 200, and the hopper pressure regulator setting signal selector 101.

The pressure regulator 100 of the feed hopper 40 compares the set value with the pressure measurement value of the feed hopper 40 and generates a control output signal to reduce the magnitude of the deviation within the controller 100 when the deviation occurs. The pressure of the hopper 40 is increased.

When the pressure measurement value reaches the minimum pulverized coal injection minimum pressure set value (ST1K), the second stage pressure condition processing unit 400 determines the completion of the primary pressure and outputs the primary pressure contact output signal of the second stage pressure condition signal selector 430. OFF to terminate the primary pressure.

As described above, when the primary pressure is terminated, the flow nitrogen pressurization mode 431 is selected as the second stage pressure condition signal selector 430.

When the flow nitrogen pressurization mode 431 is selected, the control mode of the pressure regulator 100 is switched from the remote REM to manual MAN, and the pressure regulator 100 is pressurized 102 and the back pressure control valve 103. Keep it at the value of 50%, which is the output value that is all closed.

In addition, from this time, the flow nitrogen flow control valve 111 is opened by the control signal controlled by the flow nitrogen flow controller 110, so that the pressure of the feed hopper 40 is increased by the supply of flow nitrogen.

When the flow nitrogen pressurization proceeds, as shown in FIG. 8, the secondary pressurization condition determination outputs the secondary pressurization contact point.                     

In the pressure regulator 100 of the hopper 40, the control mode is switched from the manual MAN to the remote REM by the sequence processor 210, and the feed hopper 40 is also selected as the two-stage pressure mode.

In addition, as the secondary pressure is started, the signal is gradually increased by the ratio 421 of the secondary pressure at a constant rate, and the output signal of the proportioner 421 matches the required pressure value for each blowing amount shown in FIG. 9 previously set. If the increase or increase of the output signal of the proportioner 421 is stopped, this output signal is set through the pressure mode selector 430, the operation mode selector 200, the controller mode selector 101, do.

The pressure regulator 100 of the feed hopper 40 compares the set value with the pressure measurement value of the feed hopper 40 and generates a control output signal to reduce the magnitude of the deviation within the controller 100 when the deviation occurs. This will increase the pressure of the hopper.

When the pressure measurement value reaches the required pressure value for the pulverized coal injection amount, the second stage pressure condition processing unit 400 determines the completion of the secondary pressure, turns off the secondary pressure contact output signal of the selector 430, and terminates the secondary pressure. .

When the secondary pressurization is finished, the blowing condition and the blowing state are checked and the blowing is performed, thereby preventing wear of the back pressure control valve 103 generated in the waiting time after the completion of the pressing.

As described above, the present invention is a pressurization method performed to fill the pressure for blowing the pulverized coal in the feed hopper after the filling of the feed hopper in the conventional continuous pressurization, by pressurizing by the flow nitrogen after the first pressurization The system recognizes the progress of the current hopper and determines the second pressurization time, and then develops a two-stage pressurization method to pressurize the secondary according to the decision to eliminate unnecessary blow waiting time, which is the main wear factor of the back pressure control valve 103. In order to secure the waiting time to proceed to the next blown state, it is possible to prevent the wear of the control valve generated in the air and to stabilize the blown amount control, thereby facilitating the production of waste water in the blast furnace.

Claims (7)

In the apparatus for controlling the internal pressure of the feed hopper 40 in the pulverized coal injection facility, A hopper signal measuring processor 300 for receiving and processing the weight information and the pressure information of the feed hopper 40 and the pressure information of the blast furnace opening 60; A sequence processor 210 which determines whether the filling condition, the blowing condition, the back pressure condition, and the pressing condition are satisfied according to the contact signal received from the hopper signal measuring processor 300; A two-stage pressure condition processor 400 comprising logic for determining a pressurization condition according to the feed hopper 40 mode state and the pressure state of the feed hopper 40 from the hopper signal measurement processor 300; A secondary pressure condition processor 420 including logic for determining the secondary pressure condition according to the primary pressure and the flow nitrogen pressure in accordance with the determination condition of the second pressure condition processor 400; A primary pressure ratio 411 and a secondary pressure ratio 421 for pressurizing nitrogen according to conditions determined by the second stage pressure condition processor 400 and the secondary pressure condition processor 420; The two-stage pressure condition signal selector 430 for selecting the first and second pressure programs according to the two-stage pressure control signals of the primary pressure ratio 411 and the secondary pressure ratio 421 and the contact point outputted therefrom. A hopper operation mode selector 200 for selecting a control program according to a signal; Hopper pressure control device for preventing the back pressure control valve wear in the pulverized coal injection facility, characterized in that consisting of a hopper pressure control system setting signal selector 101 for controlling the hopper pressure control system 100 according to the signal of the hopper operation mode selector 200. . The method according to claim 1, The hopper signal measurement processing unit 300 is a weight calculation unit 320 for calculating the weight information from the load cell 44 installed in the lower portion of the feed hopper 40, the feed hopper 40 and the blast furnace 60 Hopper pressure control device for preventing wear of the back pressure control valve in the pulverized coal injection facility, characterized in that the pressure measurement processing unit 310 for receiving and processing the pressure information. The method according to claim 1, The two-stage pressure condition processing unit 400 is the primary pressure, the flow nitrogen pressure, the secondary pressure according to the feed hopper 40 mode state and the pressure state of the feed hopper 40 from the hopper signal measurement processing unit 300, respectively. Hopper pressure control device for preventing wear of the back pressure control valve in the pulverized coal injection facility, characterized in that consisting of logic (Logic) to determine the condition. The filling side 41 and back pressure control side 103 of the feed hopper 40 are completely opened, the pressure control side 102 is closed, and the flow control side 111 is opened to remove pulverized coal from the pulverized coal storage tank 30. Filling with a feed hopper 40; When the pulverized coal filling is completed, completely closing the back pressure control valve (103), opening the pressure control valve (102), and continuously opening the flow control valve (111); When the primary pressure is completed, continuing to close the back pressure control valve (103), close the pressure control valve (102) again, and open the flow control valve (111) to pressurize with fluid nitrogen; Continuing to close the back pressure control valve (103), open the pressure control valve (102), and continuously open the flow control valve (111) to pressurize the secondary nitrogen after the flow nitrogen pressurization is completed; When the secondary pressurization is completed, opening the back pressure control valve (103) and the pressure control valve (102), and continuously opening the flow control valve (111) to blow the pulverized coal into the blast furnace vent (60); When the pulverized coal injection is completed, the pulverized coal injection comprises a step of opening the back pressure control valve 103, closing the pressure control valve 102 again, and opening the flow control valve 111 to back pressure. Hopper pressure control method to prevent back pressure control valve wear in equipment. The method according to claim 4, The first step of pressurizing the hopper pressure control method for preventing wear of the back pressure control valve in the pulverized coal injection facility, characterized in that to press the internal pressure of the feed hopper 40 from 7kg / ㎠. The method according to claim 4, The pressurizing with the flow nitrogen is a hopper pressure control method for preventing wear of the back pressure control valve in the pulverized coal injection facility, characterized in that for pressurizing the internal pressure of the feed hopper 40 from 11 kg / ㎠. The method according to claim 4, The secondary pressurizing step is a hopper pressure control method for preventing wear of the back pressure control valve in the pulverized coal injection facility, characterized in that to pressurize the internal pressure of the feed hopper 40 from 11 to 12kg / ㎠.

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