JP2009256090A - Pressurized powder supplying device and operating method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress changes of the supplying amount of powder discharged from a feed hopper when the power is transported from a rock hopper to the feed hopper, in a rock hopper system pressurizing the power and supplying that. <P>SOLUTION: An opening variable valve is installed in a second pressure equalizer communicating a rock hopper upper portion and a feed hopper upper portion, and an opening is controlled according to powder transporting speed to the feed hopper. The opening variable valve is provided at a lock hopper outlet, thereby controlling the opening according to the power transporting speed from the lock hopper to the feed hopper. An aeration gas supplying system is provided on the lock hopper lower portion of the piping of the rock hopper lower portion, thereby controlling the amount of the aeration gas according to the powder transporting speed from the lock hopper to the feed hopper. The aeration gas is supplied into plural stages of the lock hopper lower portion. A supplying interval of the aeration gas from each stage is controlled according to the power transporting speed to the feed hopper. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a pressurized powder supply apparatus that pressurizes a powder and continuously conveys air by air, and an operation method thereof.

  There is a lock hopper system as a method of continuously supplying powder under pressure, which is applied to a coal supply system of a coal gasification system (for example, see Patent Documents 1 and 2). The prior art of coal supply by this lock hopper system will be described.

  In the lock hopper system, the powder is filled in the feed hopper and continuously supplied from the feed hopper to the gasification furnace. Since the gasification furnace is operated under pressure, it is necessary to always keep the pressure of the feed hopper higher than the pressure of the gasification furnace in order to prevent backflow.

  In order to control the amount of powder discharged from the feed hopper, a flow rate adjusting valve such as a rotary valve is used. Since a groove is formed in the rotary valve, the amount of powder discharged by one rotation of the rotary valve is substantially constant. For this reason, the powder discharge amount can be controlled by the number of rotations of the rotary valve. Here, if the pressure difference between the rotary valve inlet and outlet fluctuates, the amount of powder filling the groove of the rotary valve changes or the amount of powder passing through the clearance of the rotary valve changes, resulting in loss of quantitativeness. It is. Therefore, a pressure equalizing pipe is installed to eliminate the differential pressure difference between the feed hopper and the rotary valve outlet.

  Since the feed hopper needs to be kept in a pressurized state, powder filling into the feed hopper cannot be performed from the hopper in the normal pressure state.

  In the lock hopper system, it is possible to replenish powder to the feed hopper by the following procedure without stopping the supply from the feed hopper.

  First, with the shutoff valve between the normal pressure hopper and the lock hopper closed, powder is filled into the normal pressure hopper. Next, when the lock hopper is at normal pressure and the shutoff valve between the lock hopper and the feed hopper and the shutoff valve of the pressure equalizing pipe connecting the lock hopper and the feed hopper are closed, the shutoff valve between the normal pressure hopper and the lock hopper To transfer the powder from the normal pressure hopper to the lock hopper. After the transfer is completed, the shutoff valve between the normal pressure hopper and the lock hopper is closed.

  Next, pressurized gas is supplied to the lock hopper, and the lock hopper is pressurized to a pressure equivalent to that of the feed hopper. Next, the shutoff valve between the lock hopper and the feed hopper and the shutoff valve of the pressure equalizing pipe connecting the lock hopper and the feed hopper are opened, and the powder is discharged from the lock hopper to the feed hopper.

  At this time, the volume of the gas portion of the feed hopper decreases due to powder filling, and the pressure increases. On the other hand, the volume of the gas portion of the lock hopper increases due to the discharge of powder, and the pressure decreases. The pressure equalizing pipe connecting the lock hopper and the feed hopper is installed to suppress such pressure fluctuation.

  As a method for measuring the amount of coal supplied from the feed hopper to the gasification furnace, for example, the weight of the feed hopper can be measured with a load cell and calculated from the decrease in the weight of the feed hopper.

JP-A-10-109754 Japanese Patent Laid-Open No. 10-25483

  In the conventional lock hopper system, the coal supply amount may vary within a range of about 10%. As a result of analyzing this phenomenon, it was found that it was mainly due to the following causes.

  Even if a pressure equalizing pipe connecting the lock hopper and the feed hopper is installed, if the powder transfer speed from the lock hopper to the feed hopper changes abruptly, the pressure of the feed hopper fluctuates. Since the feed hopper is always in communication with the conveyance destination, when the pressure of the feed hopper varies, the differential pressure between the feed hopper and the conveyance destination varies. Due to the variation in the differential pressure, the amount of powder discharged from the feed hopper by the rotary valve varies or the amount of carrier gas varies, so that the amount of powder supplied from the feed hopper varies greatly.

  Further, the amount of gas passing through the pressure equalizing pipe for eliminating the differential pressure between the feed hopper and the rotary valve outlet increases. Since powder may be discharged downstream on this gas, the amount of powder transported to the transport destination instantaneously increases.

  Furthermore, when the powder transfer speed from the lock hopper to the feed hopper is high, the powder remaining in the feed hopper is pressed against the powder that has dropped from the lock hopper, and bridging is suddenly resolved to transfer the powder. The amount increases or is compacted, causing the powder to bridge and affect the discharge of the powder.

  For these reasons, in the conventional lock hopper system, the fluctuation range of the powder supply amount may become large.

  An object of the present invention is to provide a lock hopper type pressurized powder supply device capable of suppressing fluctuations in the amount of powder supplied from the feed hopper during powder transfer from the lock hopper to the feed hopper, and its It is to provide a driving method.

  One of the factors that cause the amount of powder discharged from the feed hopper to fluctuate is a change in the pressure of the feed hopper caused by the amount of powder transferred when the powder is transferred from the lock hopper to the feed hopper.

  The amount of powder discharged from the hopper is determined by the outlet diameter of the hopper, and the amount of powder decreases as the outlet diameter of the hopper decreases. Based on this, in the first invention, an opening variable valve is installed at the lower outlet of the lock hopper, and the opening of the variable opening valve is controlled according to the speed of the powder transferred from the lock hopper to the feed hopper. The amount of powder transferred from the lock hopper to the feed hopper was kept constant.

  In systems where air is conveyed by pressurizing powder using a lock hopper and feed hopper, pressure equalization pipes that allow gas to communicate between the upper part of the lock hopper and the upper part of the feed hopper are installed to suppress fluctuations in pressure between the lock hopper and the feed hopper. Has been. When the pressure equalizing pipe valve is shut off, the amount of powder transferred from the lock hopper to the feed hopper is reduced. Using this principle, in the second aspect of the invention, when the transfer speed of the powder transferred from the lock hopper lower outlet to the feed hopper upper inlet increases rapidly, the gas communicates between the lock hopper upper part and the feed hopper upper part. The amount of powder transferred was controlled by shutting off the valve provided in the pressure tube.

  In addition, a variable opening valve is provided in the pressure equalizing pipe instead of the shutoff valve, or a variable opening valve is provided in addition to the shutoff valve to transfer the powder transferred from the lock hopper lower outlet to the feed hopper upper inlet. When the speed increases rapidly, the opening of the variable opening valve is made small while the shutoff valve is open.

  In the lock hopper system, an aeration gas supply line for preventing discharge defects such as bridging at the lock hopper outlet may be installed in the lower part of the lock hopper and the piping under the lock hopper. The powder discharge speed from the lock hopper varies depending on the amount of aeration gas. Therefore, in the third invention, the amount of aeration gas supplied from the aeration gas line is controlled in accordance with the powder transfer speed transferred from the lock hopper to the feed hopper. In addition, a shutoff valve was installed in the aeration gas line to control its opening and closing.

  Each of the above inventions can be implemented by combining a plurality thereof.

  According to the present invention, it is possible to suppress fluctuations in the amount of powder supplied from the feed hopper during powder transfer from the lock hopper to the feed hopper.

  Specific configurations of the pressurized powder supply apparatus and the operation method thereof according to the present invention are shown below.

  (1) A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shutoff valve, and the feed hopper is connected to a powder transfer destination device by piping, and a flow rate for adjusting the amount of powder discharged to the piping. An adjustment valve, a first pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the outlet of the flow rate adjusting valve, and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper, In each of the pressure equalizing pipes, a shut-off valve is provided, and in the air flow conveying type pressurized powder supply apparatus, a mixer for mixing the carrier gas with the powder exiting the flow rate adjusting valve is provided. A variable opening valve is provided at the outlet, and the opening of the variable opening valve is controlled in accordance with the transfer speed of the powder supplied from the lock hopper to the feed hopper. Pressurized powder compact supply device characterized by comprising a device.

  (2) A method for operating a pressurized powder supply apparatus having the configuration described in (1) above, provided at the outlet of the lock hopper according to the transfer speed of the powder supplied from the lock hopper to the feed hopper. A method for operating a pressurized powder supply apparatus, comprising: controlling an opening degree of a variable opening degree valve.

  In this operating method, when the transfer speed of the powder supplied from the lock hopper to the feed hopper becomes faster than a preset range, the opening of the variable opening valve is reduced, and when the transfer speed is slower, the variable opening valve It is preferable to increase the opening degree.

  (3) A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shut-off valve, the feed hopper is connected to a powder transfer destination device by piping, and a flow rate for adjusting the amount of powder discharged to the piping An adjustment valve, a first pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the outlet of the flow rate adjusting valve, and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper, In the air pressure conveying type pressurized powder supply apparatus, each of the pressure equalizing pipes is provided with a shutoff valve, and a mixer for mixing the carrier gas with the powder exiting the flow rate adjusting valve is provided. A control device is provided that opens and closes the shut-off valve provided in the second pressure equalizing pipe in accordance with the transfer speed of the powder supplied to the feed hopper. Pressurized powder compact supply device for.

  (4) A method for operating a pressurized powder supply apparatus having the configuration described in (3) above, wherein the second pressure equalizing pipe is provided in accordance with the transfer speed of the powder supplied from the lock hopper to the feed hopper. A method for operating a pressurized powder supply apparatus, comprising: opening and closing a shut-off valve provided.

  This operation method is effective when the transfer speed of the powder supplied from the lock hopper to the feed hopper becomes faster than a preset range, and it is preferable to close the shut-off valve at that time.

  (5) A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shut-off valve, the feed hopper is connected to a powder transfer destination device by piping, and a flow rate for adjusting the amount of powder discharged to the piping An adjustment valve, a first pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the outlet of the flow rate adjusting valve, and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper, In the air pressure conveying type pressurized powder supply apparatus, wherein the first pressure equalizing pipe is provided with a shut-off valve, and a mixer for mixing the carrier gas with the powder exiting the flow rate adjusting valve is provided. The pressure equalizing pipe is provided with an opening variable valve or an opening variable valve and a shutoff valve, and the second pressure equalization according to the transfer speed of the powder supplied from the lock hopper to the feed hopper. Pressurized powder compact supply apparatus characterized by comprising a control device for controlling the opening of the variable opening valve provided in.

  (6) An operation method of the pressurized powder supply apparatus having the configuration described in (5) above, wherein the second pressure equalizing pipe is set according to a transfer speed of the powder supplied from the lock hopper to the feed hopper. A method for operating a pressurized powder supply apparatus, comprising: controlling an opening of an opening variable valve provided.

  In this operation method, when the transfer speed of the powder supplied from the lock hopper to the feed hopper becomes faster than a preset range, the opening of the opening variable valve provided in the second pressure equalizing pipe It is preferable that the opening degree of the variable opening degree valve provided in the second pressure equalizing pipe is increased when the pressure is reduced.

  (7) A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shutoff valve, and the feed hopper is connected to a powder transfer destination device by piping, and the flow rate for adjusting the amount of powder discharged to the piping An adjustment valve, a first pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the outlet of the flow rate adjusting valve, and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper, In each of the pressure equalizing pipes, a shut-off valve is provided, and in the air flow conveying type pressurized powder supply apparatus, a mixer for mixing the carrier gas with the powder exiting the flow rate adjusting valve is provided. An aeration gas supply means for supplying aeration gas to a lower portion, a pipe connecting the lock hopper and the feed hopper, respectively; The aeration gas supply means provided at the lower part of the hopper is configured so that aeration gas is supplied in multiple stages, and a gas passage leading to each stage is provided with a shutoff valve, and the powder supplied from the lock hopper to the feed hopper By controlling the amount of aeration gas supplied from these aeration gas supply means and the opening / closing intervals of the plurality of shut-off valves in the aeration gas supply means provided below the lock hopper according to the body transfer speed A pressurized powder supply apparatus comprising a control device for adjusting the timing of intermittent supply.

  (8) A method for operating the pressurized powder supply apparatus having the configuration described in (7) above, wherein these aeration gas supply means are used in accordance with the transfer speed of the powder supplied from the lock hopper to the feed hopper. At least one of controlling the timing of performing intermittent supply by adjusting the amount of aeration gas supplied from the air and the opening and closing intervals of a plurality of shut-off valves in the aeration gas supply means provided at the lower portion of the lock hopper A method for operating a pressurized powder supply apparatus.

  In this operation method, when the transfer speed of the powder supplied from the lock hopper to the feed hopper becomes slower than a preset range, the aeration gas amount is increased and the powder transfer speed still does not enter the specified value. In this case, it is preferable to perform pulse supply of aeration gas, multistage blowing of aeration gas, or the like. Moreover, when the transfer speed of the powder supplied from the lock hopper to the feed hopper becomes faster than a preset range, it is preferable to reduce the amount of aeration gas.

  The amount of powder discharged from the feed hopper may fluctuate even in an operating state where the powder is not transferred from the lock hopper to the feed hopper. In such a case, the following (9) to (12) show apparatus configurations and operation methods effective for suppressing fluctuations in the amount of discharged powder.

  (9) A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shut-off valve, the feed hopper is connected to a powder transfer destination device by piping, and the flow rate for adjusting the amount of powder discharged to the piping An adjustment valve, a first pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the outlet of the flow rate adjusting valve, and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper, In the pressurized powder supply apparatus of the air current conveying system, each of the pressure equalizing pipes is provided with a shut-off valve, and a mixer for mixing the carrier gas with the powder exiting the flow rate adjusting valve is provided. The pressure equalizing pipe is provided with a variable opening degree valve, and the opening degree of the variable opening degree valve provided in the first pressure equalizing pipe is controlled according to the discharge amount per unit opening degree of the flow rate adjusting valve. Pressurized powder supply apparatus provided with a control device.

  (10) A method for operating the pressurized powder supply apparatus having the configuration described in (9), wherein the first pressure equalizing pipe is provided in accordance with a discharge amount per unit opening of the flow rate adjustment valve. A method for operating a pressurized powder supply apparatus for controlling the opening of the variable opening valve.

  Here, the fact that the amount of discharge per unit opening changes means that the amount of powder supplied per hour changes. If the dispensing amount per unit opening of the flow control valve is greater than the preset range, the opening of the variable opening valve is reduced. Increase the degree.

  (11) A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shut-off valve, the feed hopper is connected to a powder transfer destination device by piping, and a flow rate for adjusting a powder discharge amount to the piping. An adjustment valve, a first pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the outlet of the flow rate adjusting valve, and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper, In each of the pressure equalizing pipes, a shutoff valve is provided, and an air flow conveying type pressurized powder supply apparatus is provided with a mixer for mixing the carrier gas with the powder exiting the flow rate adjusting valve. An aeration gas supply means for supplying aeration gas to the lower part is provided, and an aeration gas is provided in a pipe between the feed hopper and the flow rate adjusting valve. An aeration gas supply means for supplying the aeration gas, the aeration gas supply means provided at the lower portion of the feed hopper is configured so that aeration gas is supplied in multiple stages, and a gas passage leading to each stage is provided with a shutoff valve, The amount of aeration gas supplied from the aeration gas supply means according to the amount of discharge per unit opening of the flow rate adjusting valve and a plurality of the shut-off valves in the aeration gas supply means provided below the feed hopper The powder supply apparatus provided with the control apparatus which performs at least one of controlling the timing of intermittent supply by controlling the opening-and-closing space | interval.

  (12) The operation method of the pressurized powder supply apparatus according to (11), wherein the amount of aeration gas supplied from the aeration gas supply means according to the amount of discharge per unit opening of the flow rate adjustment valve And at least one of controlling the timing of intermittent supply by adjusting the opening and closing intervals of a plurality of shut-off valves provided in the lower part of the feed hopper, Driving method.

  In this operation method, it is preferable to increase the amount of aeration gas when the discharge amount per unit opening of the flow rate adjusting valve is smaller than a preset value, and then the aeration gas is supplied by pulsing the aeration gas. It is preferable to perform control such as multistage blowing. On the other hand, when the amount of discharge per unit opening of the flow rate adjusting valve is greater than a preset value, it is preferable to reduce the amount of aeration gas or stop the supply of aeration gas.

  A plurality of the apparatus configurations and operation methods described in (9) to (12) above can be combined.

  The pressurized powder supply apparatus and the operation method thereof according to the present invention can be applied to various systems that pressurize and supply powder, including a coal gasification system. In the coal gasification system, pulverized coal is gasified under pressure. The present invention can be applied to fine coal supply to the reaction furnace in the coal gasification system, and to a portion where unreacted coal (char) in the generated gas is separated from the generated gas and recycled to the reactor.

  Examples are shown below, but the present invention is not limited to these examples.

  In this embodiment, the case where a variable opening valve is provided at the outlet of the lock hopper will be described with reference to FIG.

  The powder is filled in the feed hopper 3 and is continuously supplied from the feed hopper to the conveyance destination 7. When the powder conveyance destination is in a pressurized state, the feed hopper 3 is always held in a state higher than the pressure at the conveyance destination. When the powder is discharged from the feed hopper 3 and the level of the powder in the feed hopper is lowered, the pressure at the top of the feed hopper is lowered.

  Therefore, a part of the carrier gas 11 is supplied to the upper portion of the feed hopper through the pipe 27 to suppress the pressure drop of the feed hopper 3. The supply amount of the carrier gas 11 is measured by the feed hopper pressurized gas flow meter 13 and controlled by the feed hopper pressurized gas flow control valve 47 so that the set amount is supplied.

  In order to control the amount of powder discharged from the feed hopper 3, a rotary valve 43 is installed at the outlet of the feed hopper 3 as a flow rate adjusting valve. The powder discharge amount can be controlled by the number of rotations of the rotary valve 43. If the pressure difference between the rotary valve inlet and outlet fluctuates, the quantitativeness is impaired. Therefore, the first pressure equalizing pipe 25 that connects the feed hopper and the rotary valve outlet is provided, and the shutoff valve 45 is controlled to be opened and closed to eliminate the differential pressure fluctuation therebetween. For example, an impact flow meter 5 is used to measure the amount of discharged powder.

  The powder discharged from the rotary valve 43 is sent to the mixer 6 through the pipe 23, where it is carried on the flow of the carrier gas 11 and conveyed downstream through the pipe 28. The supply amount of the carrier gas 11 is measured by the carrier gas flow meter 12 provided in the pipe 26 and is controlled by the carrier gas flow rate adjustment valve 46 so that the set amount is supplied.

  Here, the indicated value of the impact flow meter 5 is affected by the gas passing through the impact flow meter. The amount of gas passing through the impact flow meter 5 increases and decreases with changes in the pressure of the feed hopper 3 and the pressure of the transfer destination 7. Therefore, the indicated value of the impact flow meter 5 is obtained by determining the powder supply speed based on the change per unit time of the amount of powder filled in the feed hopper obtained by the load cell 4 installed in the feed hopper 3. Correct as needed using.

  The feed hopper 3 must be kept in a pressurized state, and powder filling into the feed hopper cannot be performed from the hopper in the normal pressure state. Therefore, first, the normal pressure hopper 1 is filled with powder in a state where the shutoff valve 41 of the pipe 21 leading from the normal pressure hopper 1 to the lock hopper 2 is closed. Next, with the lock hopper 2 at normal pressure and the shutoff valve 42 of the pipe 22 and the shutoff valve 44 of the second pressure equalizing pipe 24 communicating from the lock hopper to the feed hopper being closed, the shutoff valve 41 is opened and The powder is transferred from the pressure hopper 1 to the lock hopper 2. After the transfer is completed, the shutoff valve 41 is closed.

  Next, the shutoff valve 48 of the pipe 29 for supplying the pressurized gas 14 to the lock hopper 2 is opened, the pressurized gas 14 is supplied to the lock hopper 2, and the lock hopper 2 is pressurized to the same pressure as the feed hopper 3. Next, the shutoff valve 42 and the shutoff valve 44 of the second pressure equalizing pipe 24 are opened, and the powder is discharged from the lock hopper to the feed hopper.

  FIG. 7 shows the change over time in the weight change W of the load cell of the feed hopper, the transfer differential pressure ΔP which is the differential pressure between the feed hopper and the transfer destination, and the powder supply amount F when the powder is discharged from the lock hopper to the feed hopper. Show.

  At this time, the volume of the gas portion of the feed hopper 3 decreases due to the powder filling, and the pressure increases. On the other hand, the volume of the gas portion of the lock hopper 2 increases due to powder discharge, and the pressure decreases. The second pressure equalizing pipe 24 is installed to suppress such pressure fluctuation.

  However, even if the second pressure equalizing pipe 24 is installed, the feed hopper pressure fluctuates if the powder transfer speed from the lock hopper to the feed hopper changes abruptly. Since the feed hopper is always in communication with the conveyance destination, when the pressure of the feed hopper varies, the differential pressure between the feed hopper and the conveyance destination varies (conveyance differential pressure in FIG. 7). Due to the fluctuation of the differential pressure, the amount of powder discharged from the feed hopper by the rotary valve 43 may fluctuate or the amount of carrier gas may fluctuate. As a result, the amount of powder supplied from the feed hopper may fluctuate greatly. (Powder supply amount in FIG. 7). This fluctuation in the differential pressure becomes an error generation factor in powder supply amount measurement by the impact flow meter 5.

  Further, the amount of gas passing through the first pressure equalizing pipe 25 increases, and the powder may be discharged downstream on this gas, so the amount of powder transported to the transport destination increases instantaneously. There is.

  Furthermore, when the powder transfer speed from the lock hopper to the feed hopper is high, the powder remaining in the feed hopper is pressed against the powder dropped from the lock hopper, bridging is suddenly eliminated, and the powder conveyance amount is increased. Rapid increase or consolidation makes the powder bridging easier and affects powder discharge.

  In order to solve these problems, in this embodiment, a variable opening valve 55 is installed in the pipe 22 connecting the lower portion of the lock hopper and the feed hopper inlet. Further, a control device 8 for controlling the opening degree of the opening degree variable valve 55 is installed. The control device 8 is inputted with the value of the load cell 4 installed in the feed hopper 3 and the amount of powder supplied from the feed hopper measured by the impact flow meter 5. The powder transfer speed from the lock hopper to the feed hopper depends on the increase in the powder weight per unit time by the load cell 4 installed in the feed hopper, from the feed hopper per unit time measured by the impact flow meter 5. It is obtained by adding the amount of discharged powder.

  The control device 8 obtains the opening setting value of the opening variable valve 55 so that the powder transfer speed from the lock hopper to the feed hopper thus obtained is constant or substantially constant. Control the opening. By this operation, as shown in FIG. 8, even when the lock hopper is discharged from the feed hopper, there is no fluctuation in the conveyance differential pressure (or the pressure of the feed hopper), and fluctuation in the powder supply amount is suppressed.

  According to the present embodiment, the powder transfer speed from the lock hopper to the feed hopper is kept constant or substantially constant, so that there is no pressure fluctuation between the lock hopper and the feed hopper, and the lock hopper to the feed hopper. The powder remaining in the feed hopper is pressed by the dropped powder, and the flow characteristics of the powder do not change. According to the present embodiment, it is possible to suppress fluctuations in the amount of powder supplied from the feed hopper within ± 3% (FIG. 8).

  In this embodiment, the case where the shutoff valve 44 of the second pressure equalizing pipe 24 connecting the feed hopper and the lock hopper is controlled according to the powder transfer speed from the lock hopper to the feed hopper will be described with reference to FIG. . The device configuration of the present embodiment is the same as that of the first embodiment except that the opening degree variable valve 55 is not provided at the lock hopper outlet and the control device is not provided.

  The second pressure equalizing pipe 24 is a pipe for suppressing pressure fluctuations of the lock hopper 2 and the feed hopper 3. When the shutoff valve 44 of the second pressure equalizing pipe is shut off and when the shutoff valve 44 is opened, comparing the powder transfer speed from the lock hopper to the feed hopper, the shutoff valve 44 is open. Is faster. Pressure fluctuations occur when the powder transfer speed from the lock hopper 2 to the feed hopper 3 is high, so when the powder transfer speed from the lock hopper to the feed hopper is monitored and the transfer speed exceeds the specified value In this case, the shutoff valve 44 is closed.

  A control device 8 is installed for this control. The control device 8 receives the value of the load cell 4 installed in the feed hopper and the amount of powder supplied from the feed hopper measured by the impact flow meter 5. Using these values, the control device 8 calculates the powder transfer speed from the lock hopper to the feed hopper. This value is compared with a specified value for suppressing pressure fluctuation, and an opening / closing command for the shutoff valve 44 provided in the second pressure equalizing pipe 24 is issued.

  In this embodiment, the powder transfer speed from the lock hopper to the feed hopper is kept constant or substantially constant, so that fluctuations in the amount of powder supplied from the feed hopper can be suppressed. The fluctuation of the powder supply amount can be suppressed to ± 3% or less.

  In the second embodiment, the shutoff valve 44 provided in the second pressure equalizing pipe 24 is opened and closed according to the amount of powder transferred from the lock hopper to the feed hopper. In order to finely control the body transfer speed, it is desirable to provide a variable opening valve in the second pressure equalizing pipe 24. This example will be described with reference to FIG. In the apparatus configuration of this embodiment, an opening degree variable valve 49 is provided in the second pressure equalizing pipe 24, and the opening degree of the opening degree variable valve 49 is further controlled based on the powder transfer speed from the lock hopper to the feed hopper. Except for the point that is controlled, this is the same as the second embodiment.

  In the apparatus configuration of this embodiment shown in FIG. 4, the second pressure equalizing pipe 24 is provided with a variable opening valve 49 in addition to the shutoff valve 44. Although it is possible to omit the shutoff valve 44, it is generally desirable to provide both valves because the variable opening valve has poor shutoff performance. In the case of the present embodiment, the control device 8 issues an opening degree command to the opening degree variable valve 49 according to the calculated powder transfer speed from the lock hopper to the feed hopper.

  According to this embodiment, the powder transfer speed from the lock hopper to the feed hopper can be kept constant, the fluctuation of the powder supply amount from the feed hopper can be suppressed, and the fluctuation range can be suppressed to ± 3% or less. It is.

  An embodiment in which aeration gas is supplied to the pipe at the lower part of the lock hopper and the outlet of the lock hopper and the supply amount thereof is controlled to keep the powder transfer speed from the lock hopper to the feed hopper constant will be described with reference to FIG.

  An aeration pipe 30 is installed in the lower part of the lock hopper 2 or the pipe 22 connecting the lock hopper and the feed hopper, and the aeration gas 15 is supplied. The aeration pipe 30 has a plurality of aeration gas supply ports for supplying aeration gas to the lower portion of the lock hopper 2, and has cutoff valves 52a, 52b, and 52c in gas passages connected to the aeration gas supply ports, respectively. These shut-off valves are simultaneously opened and closed at intervals of several seconds to supply aeration gas 15 intermittently. This is to prevent powder bridging and the like in the lock hopper 2 and to smoothly discharge the powder from the lock hopper 2 to the feed hopper 3.

  The powder transfer speed from the lock hopper 2 to the feed hopper 3 is changed by the supply amount of the aeration gas and the intermittent supply of the aeration gas 15 according to the opening / closing intervals of the shutoff valves 52a, 52b, 52c. This is used in the present embodiment.

  For this purpose, a control device 8 is installed. The control device 8 is supplied with the value of the load cell 4 installed in the feed hopper 3 and the amount of powder supplied from the feed hopper measured by the impact flow meter 5. Using these values, the control device 8 calculates the powder transfer speed from the lock hopper to the feed hopper. In accordance with this value, the aeration flow rate adjusting valves 51a and 51b installed in the aeration pipe 30 are controlled. Moreover, the open / close intervals of the shutoff valves 52a, 52b, 52c are controlled.

  According to this embodiment, the powder transfer speed from the lock hopper to the feed hopper can be kept constant. For this reason, the fluctuation | variation of the powder supply amount from a feed hopper can be suppressed. The fluctuation range of the powder supply amount can be suppressed to ± 3% or less.

  In this embodiment, the aeration gas is supplied to both the lower part of the lock hopper and the pipe 22, but only the lower part of the lock hopper may be used.

  In the present embodiment, a third embodiment in which the powder transfer speed from the lock hopper to the feed hopper is controlled using a variable opening degree valve 49 installed in the second pressure equalizing pipe 24, the lower portion of the lock hopper 2, and the lock hopper. And Example 4 for controlling the aeration gas supplied to the pipe 22 connecting the feed hopper. The apparatus configuration of this embodiment is shown in FIG.

  The control device 8 receives the value of the load cell 4 installed in the feed hopper and the amount of powder supplied from the feed hopper measured by the impact flow meter 5. In accordance with this value, the control device 8 (A) the opening of the opening variable valve 49 installed in the second pressure equalizing pipe 24, (B) the opening of the aeration flow control valves 51a and 51b, and (C) the shut-off valve The opening / closing intervals of 52a, 52b, and 52c are calculated, and the command is changed.

  (A) (B) (C) Method of changing commands simultaneously for opening / closing commands of the opening variable valve 49, opening commands of the aeration flow rate adjusting valves 51a, 51b, and opening / closing interval commands of the shutoff valves 52a, 52b, 52c. Then, there are methods such as (B) following (A) and then (C). Nevertheless, if the powder transfer speed from the lock hopper to the feed hopper cannot be controlled to the specified value, it is desirable to rearrange the order of (A), (B), and (C).

  In this embodiment, by combining a plurality of methods, the reliability for controlling the powder transfer speed from the lock hopper to the feed hopper is improved. Moreover, fine control is possible by combining a plurality of methods, and the amount of powder supplied from the feed hopper can be suppressed to ± 3% or less.

  In this embodiment, an operation method for suppressing fluctuations in the amount of supplied coal during normal operation will be described with reference to FIG. The normal operation is an operation state when there is no powder transfer from the lock hopper to the feed hopper. Even in such an operating state, the amount of powder supplied from the feed hopper may vary.

  In this case, an opening variable valve is provided in the first pressure equalizing pipe 25 that eliminates the pressure difference between the feed hopper 3 and the outlet of the rotary valve 43, and the opening is the amount of discharge per unit opening of the rotary valve 43. Change according to. Alternatively, the aeration gas supply unit similar to that of the fifth embodiment is provided in the lower part of the feed hopper 3 and the pipe connecting the feed hopper and the rotary valve 43, and the same aeration gas supply control is performed.

  In addition, although description was abbreviate | omitted, in FIG. 2, the lower part of the feed hopper 43 and the piping which connects between a feed hopper and the rotary valve 43 were shown with the aeration gas supply means. Further, in FIG. 5, the aeration gas 15 is sent to the aeration gas supply means on the lock hopper side and also to the aeration gas supply means on the feed hopper side, and both aeration gas supply means are controlled by the control device 8. I showed what I did.

  In FIG. 6, a variable opening valve 50 is installed in the first pressure equalizing pipe 25 that eliminates the pressure difference between the feed hopper 3 and the outlet of the rotary valve 43, and the opening degree of the valve is controlled by the control device 9. It has become so. In addition, an aeration gas supply system having the same configuration as that on the lock hopper side is provided in a lower portion of the feed hopper 3 and a pipe 56 connecting the feed hopper and the rotary valve 43.

  The aeration gas supply system on the feed hopper side is provided with a flow rate adjusting valves 53 a and 53 b for aeration gas supplied to the lower portion of the feed hopper 3 and the pipe 56 and a plurality of aeration supply ports supplied to the lower portion of the feed hopper 3. It has aeration gas supply means for supplying aeration gas to the valves 54a, 54b, 54c and the pipe 56 at the outlet of the feed hopper.

  The control device 9 controls the opening and closing intervals of the shut-off valves 54a, 54b, 54c that intermittently supply the amount of these aeration gases and the aeration gas, and the opening of the variable opening valve 50.

  The value of the load cell 4 installed in the feed hopper and the amount of powder supplied from the feed hopper measured by the impact flow meter 5 are input to the control device 9. In particular, the discharge amount per unit opening of the flow rate adjusting valves 53a and 53b is used as a reference. According to this value, the opening of the opening variable valve 50 installed in the first pressure equalizing pipe, the opening of the flow rate adjusting valves 53a and 53b of the aeration gas, and the opening and closing intervals of the shutoff valves 54a, 54b and 54c are calculated. To do. The opening command of the variable opening valve 50, the opening command of the flow rate adjusting valves 53a and 53b of the aeration gas, and the opening / closing interval command of the shut-off valves 54a, 54b and 54c may be changed at the same time or step by step. You may move it. When the transfer speed from the lock hopper to the feed hopper cannot be controlled to the specified value, the combination is changed as appropriate.

  In the present embodiment, the reliability for controlling the amount of powder discharged from the feed hopper is improved by combining a plurality of methods. Moreover, fine control is possible by combining a plurality of methods, and the amount of powder supplied from the feed hopper can be suppressed to ± 3% or less.

It is a block diagram of the pressurized powder supply apparatus which concerns on the Example of this invention made to control the opening degree of the opening degree variable valve of a lock hopper exit. It is a block diagram of the pressurized powder supply apparatus which concerns on the Example of this invention. It is a block diagram of the pressurized powder supply apparatus which concerns on the Example of this invention which controls opening / closing of the cutoff valve of the pressure equalization pipe | tube which eliminates the pressure difference of a lock hopper and a feed hopper. It is a block diagram of the pressurized powder supply apparatus which concerns on the Example of this invention which provides an opening variable valve in the pressure equalization pipe | tube which eliminates the pressure difference of a lock hopper and a feed hopper, and controls the opening degree. It is a block diagram of the pressurized powder supply apparatus which concerns on the Example of this invention provided with the aeration gas supply means. It is a block diagram of the pressurized powder supply apparatus which concerns on another Example provided with the aeration gas supply means. It is a figure which shows the time-dependent change of the weight change of a load cell of a feed hopper, a conveyance differential pressure, and a powder supply amount when powder is discharged | paid out from a lock hopper to a feed hopper. It is a figure which shows progress change of the hopper weight at the time of powder discharge | payout from a lock hopper to a feed hopper, a powder supply amount, and a conveyance differential pressure.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Normal pressure hopper, 2 ... Lock hopper, 3 ... Feed hopper, 4 ... Load cell, 5 ... Impact flowmeter, 6 ... Mixer, 7 ... Conveyance destination, 8 ... Control apparatus, 9 ... Control apparatus, 11 ... Conveyance gas , 14 ... pressurized gas, 15 ... aeration gas, 22 ... piping, 23 ... piping, 24 ... second pressure equalizing tube, 25 ... first pressure equalizing tube, 41 ... shutoff valve, 42 ... shutoff valve, 43 ... rotary valve , 44 ... shutoff valve, 45 ... shutoff valve, 49 ... variable opening valve, 50 ... variable opening valve, 51a, 51b ... aeration gas flow rate adjustment valve, 52a, 52b, 52c ... shutoff valve, 53a, 53b ... aeration gas Flow rate adjusting valves, 54a, 54b, 54c... Shut-off valves, 55.

Claims (10)

  A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shutoff valve, the feed hopper is connected to a powder transfer destination device by piping, and a flow rate adjusting valve for adjusting the amount of powder discharged to the piping is provided. A first pressure equalizing pipe that eliminates the pressure difference between the outlets of the feed hopper and the flow rate adjustment valve, and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper. In an air current conveying type pressurized powder supply apparatus in which a pressure valve is provided with a shut-off valve and a mixer for mixing the carrier gas with the powder exiting the flow rate adjusting valve is opened at the outlet of the lock hopper. A control device for controlling the opening of the variable opening valve according to the transfer speed of the powder supplied from the lock hopper to the feed hopper. Pressurized powder supply apparatus, characterized in that was e.   A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shutoff valve, the feed hopper is connected to a powder transfer destination device by piping, and a flow rate adjusting valve for adjusting the amount of powder discharged to the piping is provided. A first pressure equalizing pipe that eliminates the pressure difference between the outlets of the feed hopper and the flow rate adjustment valve, and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper. Each of the pressure pipes is provided with a shut-off valve, an opening variable valve is provided at the outlet of the lock hopper, and a mixer for mixing the carrier gas with the powder exiting the flow rate adjusting valve is provided. A method of operating a green compact supply device, wherein the opening of the variable opening valve is controlled according to a transfer speed of powder supplied from the lock hopper to the feed hopper. How the operation of the pressurized powder supply apparatus being characterized in that the so that.   A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shutoff valve, the feed hopper is connected to a powder transfer destination device by piping, and a flow rate adjusting valve for adjusting the amount of powder discharged to the piping is provided. A first pressure equalizing pipe that eliminates the pressure difference between the outlets of the feed hopper and the flow rate adjustment valve, and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper. In the pressurized powder supply apparatus of the air current conveyance system, wherein the pressure pipes are each provided with a shut-off valve, and a mixer for mixing the carrier gas with the powder that has exited the flow rate adjusting valve, the feed hopper from the lock hopper to the feed hopper And a controller that opens and closes the shut-off valve provided in the second pressure equalizing pipe in accordance with a transfer speed of the powder supplied to the second pressure equalizing pipe. Powder supplying device.   A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shutoff valve, the feed hopper is connected to a powder transfer destination device by piping, and a flow rate adjusting valve for adjusting the amount of powder discharged to the piping is provided. A first pressure equalizing pipe that eliminates the pressure difference between the outlets of the feed hopper and the flow rate adjustment valve, and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper. An operation method of a pressurized powder supply apparatus of an air current conveyance system, wherein each pressure tube is provided with a shut-off valve, and a mixer for mixing a carrier gas with powder discharged from the flow rate adjustment valve, The shut-off valve provided in the second pressure equalizing pipe is opened and closed according to the transfer speed of the powder supplied from the hopper to the feed hopper. How the operation of the pressurized powder supply apparatus.   A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shutoff valve, the feed hopper is connected to a powder transfer destination device by piping, and a flow rate adjusting valve for adjusting the amount of powder discharged to the piping is provided. A first pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the outlet of the flow rate adjustment valve; and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper. The pressure equalizing pipe is provided with a shut-off valve, and is provided with a mixer for mixing the carrier gas with the powder exiting the flow rate adjusting valve. In the second pressure equalizing pipe according to the transfer speed of the powder supplied from the lock hopper to the feed hopper. The obtained compressed compact supply apparatus characterized by comprising a control device for controlling the opening of the variable opening of the valve.   A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shutoff valve, the feed hopper is connected to a powder transfer destination device by piping, and a flow rate adjusting valve for adjusting the amount of powder discharged to the piping is provided. A first pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the outlet of the flow rate adjustment valve; and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper. The pressure equalizing pipe is provided with a shutoff valve, the second pressure equalizing pipe is provided with a variable opening valve or a variable opening valve and a shutoff valve, and the carrier gas is mixed with the powder discharged from the flow rate adjusting valve. An operation method of a pressurized powder supply device of an air current conveying system provided with a mixer, wherein the powder hopper is supplied from the lock hopper to the feed hopper according to a transfer speed of the powder. How the operation of the pressurized powder supply apparatus being characterized in that so as to control the opening of the variable opening of the valve provided in the second equalizing pipe.   A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shutoff valve, the feed hopper is connected to a powder transfer destination device by piping, and a flow rate adjusting valve for adjusting the amount of powder discharged to the piping is provided. A first pressure equalizing pipe that eliminates the pressure difference between the outlets of the feed hopper and the flow rate adjustment valve, and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper. In the pressurized powder supply device of the air current conveyance system, each of the pressure pipes is provided with a shutoff valve, and is equipped with a mixer for mixing the carrier gas with the powder exiting the flow rate adjustment valve, An aeration gas supply means for supplying aeration gas to each of the lock hopper and a pipe connecting the feed hopper; The aeration gas supply means at the lower part of the apparatus is configured so that aeration gas is supplied in multiple stages, and a gas passage leading to each stage is provided with a shut-off valve, respectively, for transferring powder supplied from the lock hopper to the feed hopper According to the speed, the amount of aeration gas supplied from these aeration gas supply means and the opening / closing intervals of the plurality of shut-off valves provided in the aeration gas supply means provided below the lock hopper are adjusted. A pressurized powder supply apparatus comprising a control device for controlling the timing of intermittent supply.   A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shutoff valve, the feed hopper is connected to a powder transfer destination device by piping, and a flow rate adjusting valve for adjusting the amount of powder discharged to the piping is provided. A first pressure equalizing pipe that eliminates the pressure difference between the outlets of the feed hopper and the flow rate adjustment valve, and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper. Each of the pressure pipes is provided with a shutoff valve, and further provided with aeration gas supply means for supplying aeration gas to a lower part of the lock hopper and a pipe connecting the lock hopper and the feed hopper, and the aeration gas at the lower part of the lock hopper The gas supply means is configured to supply aeration gas in multiple stages, and in each stage Each of the gas passages is provided with a shut-off valve, and an airflow conveying type pressurized powder supply apparatus is provided with a mixer for mixing the carrier gas with the powder exiting the flow rate adjusting valve. According to the transfer speed of the powder supplied from the lock hopper to the feed hopper, the lower part of the lock hopper and the aeration gas supply means provided in the pipe connecting the lock hopper and the feed hopper are supplied. Executing at least one of controlling the timing of intermittent supply by adjusting the amount of aeration gas and the opening and closing intervals of the plurality of shut-off valves in the aeration gas supply means provided in the lower part of the lock hopper A method for operating a pressurized powder supply apparatus.   A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shutoff valve, the feed hopper is connected to a powder transfer destination device by piping, and a flow rate adjusting valve for adjusting the amount of powder discharged to the piping is provided. A first pressure equalizing pipe that eliminates the pressure difference between the outlets of the feed hopper and the flow rate adjustment valve, and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper. In the pressurized powder supply apparatus of the air current conveyance system, each of the pressure pipes is provided with a shut-off valve, and a mixer for mixing the carrier gas with the powder exiting the flow rate adjusting valve, the first pressure equalizing pipe An aeration gas supply means for supplying an aeration gas to a lower portion of the feed hopper, and the feed hopper and the flow rate adjustment bar. The aeration gas supply means for supplying aeration gas to the pipe between the feed hopper and the aeration gas supply means provided at the lower portion of the feed hopper is configured so that the aeration gas is supplied in multiple stages and communicates with each stage. The gas passages are each provided with a shut-off valve, the opening of the opening variable valve provided in the first pressure equalizing pipe according to the amount of discharge per unit opening of the flow rate adjusting valve, and the aeration gas supply means A control device is provided for controlling at least one of the amount of supplied aeration gas and the opening / closing interval control of the plurality of shut-off valves in the aeration gas supply means provided below the feed hopper. Powder supply device.   A normal pressure hopper, a lock hopper, and a feed hopper are sequentially connected via a shutoff valve, the feed hopper is connected to a powder transfer destination device by piping, and a flow rate adjusting valve for adjusting the amount of powder discharged to the piping is provided. A first pressure equalizing pipe that eliminates the pressure difference between the outlets of the feed hopper and the flow rate adjustment valve, and a second pressure equalizing pipe that eliminates the pressure difference between the feed hopper and the lock hopper. Each of the pressure pipes is provided with a shutoff valve, the first pressure equalizing pipe is provided with an opening degree variable valve, an aeration gas supply means for supplying aeration gas to a lower portion of the feed hopper, and the feed hopper and the flow rate adjustment An aeration gas supply means for supplying aeration gas to a pipe between the valve and the feed hopper; The aeration gas supply means provided in the lower part is configured to supply aeration gas in multiple stages, and a gas passage leading to each stage is provided with a shut-off valve, respectively, and a carrier gas is supplied to the powder discharged from the flow rate adjustment valve. An operation method of a pressurized powder supply device of an air flow conveying system provided with a mixer for mixing, wherein the first pressure equalizing pipe is provided according to a discharge amount per unit opening of the flow rate adjusting valve. The intermittent opening is adjusted by adjusting the opening of the variable opening valve, the amount of aeration gas supplied from the aeration gas supply means, and the opening and closing intervals of the plurality of shut-off valves provided below the feed hopper. An operation method of a pressurized powder supply apparatus, wherein at least one of controlling timings to be performed is executed.

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