JPH0829302A - Method and apparatus for sampling powder for analysis - Google Patents

Abstract

PURPOSE:To provide an apparatus for sampling powder for analysis by accomcarring out the sampling by an equal velocity suction according to a speed distribution in the transverse section of a powder tube in sampling by advancing a sampling nozzle into the powder tube as fuel supply tube leading to a boiler of a thermal power generation plant. CONSTITUTION:In the apparatus for sampling powder for analysis, a nozzle traverser 2 is fixed on the outer circumferential surface of a powder tube and a sampling nozzle 21 is so arranged to be able to traverse or traverse in reciprocation at a fixed speed or at a variable speed with feeders 22, 23, 24, 25, 26 and 27 on the diameter of the transverse surface of the powder tube from one internal wall (a) of the tube to the other internal wall (c) thereof via the center (b) thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sample collecting method and a sample collecting apparatus which accurately reflect the properties of a powder to be tested. Here, in the present invention, the powder includes powder, pulverized coal, fly ash and the like.

[0002]

2. Description of the Related Art A conventional powder analysis and sampling apparatus can be applied only to a so-called downward flow, in which powder flows from above to below, but the apparatus of the present invention can be applied to a downward flow, a horizontal flow and an upward flow. It has characteristics that can be applied to both. For example, various domestically produced and foreignly produced pulverized coal is used in the pulverized coal-fired boiler, which is an upward flow, and the pulverized coal has a very wide variety of characteristics depending on its place of origin, collection / storage conditions, etc. Therefore, if these are uniformly handled, it is difficult to adequately control the combustion conditions in the boiler.

[0003]

The problem to be solved by the present invention is to devise a sampling method and a sampling device for a sample which accurately reflects the properties of the powder to be tested. .

[0004]

The object of the present invention is solved by the constructions described in the claims. That is,
In particular, the problem can be solved by moving the sampling nozzle for sucking and sampling the sample in the diametrical direction of the cross section of the powder transport pipe, and adjusting the suction amount so that the air velocities inside and outside the sampling nozzle are equal.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, an apparatus for carrying out the powder analysis sampling method according to the present invention is constructed as follows.

A nozzle traverse device 2 is fixedly arranged on the outer surface of a powder pipe 1 for supplying powder as fuel to a pulverized coal-fired boiler. For the purpose of centralized control of the powder analysis sampling device, a control command wire is given only from the nozzle traverse device 2 as a block diagram in order to give a control command to the nozzle traverse device 2 and to feed back the operating state of the nozzle traverse device 2. Control device C. P. Connected to A control valve 3 is attached to the nozzle traverse device 2, and the amount of suction air for sampling from the sampling nozzle 21 is adjusted by adjusting the control valve. A cyclone 4 is connected to the conduit following the control valve 3, a duct for connecting to a suction device is connected to the upper part of the cyclone 4, and an air flow meter 5 is connected to the duct, followed by automatic on / off. An off butterfly valve 6 is connected and the duct is connected to the inlet of a suction blower (not shown) for air suction.

On the other hand, a collector / dryer 7 is connected below the cyclone 4, and a duct is connected to the top plate of the collector / dryer 7, and this duct is an automatic on / off butterfly valve 8
It is connected to the. Below the collector / dryer 7, a conduit is connected to the outlet side of the air heater 9 for supplying compressed air to the collector / dryer 7, and a duct is provided on the suction side of the air heater 9. It is connected to a compressed air source (not shown) via an air flow meter 10, a needle valve 11 for adjusting the compressed air flow rate, and a solenoid valve 12. A thermocouple 13 is arranged on the outer periphery of the lower part of the collector / dryer 7, and the thermocouple 13 is used to detect the temperature of the atmosphere in the collector / dryer 7.

Below the collecting / drying device 7, the collecting / drying device 7 is provided.
An automatic on / off butterfly valve 14 is additionally provided for opening and closing the flow path of the powder that has exited. A screw feeder 15 is connected below the automatic on / off butterfly valve 14, and a vertical duct is connected to the outlet of the screw feeder 15 so that the dry powder discharged from the screw feeder 15 is It guides to the connected rotary divider 16. The rotary divider 16 is composed of a rotary disk driven by a motor in its housing, and eight cups, for example, are arranged on the rotary disk at fixed positions at equal angular intervals on the circumference. . The cup serves to collect the powder, and the cup containing the powder is taken out from the rotary reducer 16 by opening the door of the rotary reducer 16 and conveyed to an analysis room (not shown), where the powder is analyzed. Can be used. The powder spilling downward from the rotating disk reaches the ejector 19 located therebelow, and can be returned to the powder tube 1 in front of the nozzle traverse device 2 via the duct by the ejector 19. The automatic on / off butterfly valve 18 is connected immediately before the duct from the ejector 19 is connected to the powder tube 1, and the automatic on / off butterfly valve for connecting and disconnecting the compressed air supply is also connected to the inlet of the ejector 19. 17 connected, automatic on-off butterfly valve 17
The duct is connected to a compressed air source (not shown).

For the purpose of centralized control of the powder analysis sampling device, a control command is sent from the nozzle traverse device 2 to give a control command to the nozzle traverse device 2 and to feed back the operating state of the nozzle traverse device 2. ． P. Control valve (V1) 3, automatic on / off butterfly valve (V2) 6, automatic on / off butterfly valve (V3)
8, air heater (H1) 9, solenoid valve (V4) 12, thermocouple 13, automatic on-off butterfly valve (V5) 14,
Screw feeder (M1) 15, motor M2 attached to rotary reducer 16, automatic on / off butterfly valve (V6) 17 and automatic on / off butterfly valve (V
7) 18 gives a control command to the equipment at each of these places, and in order to feed back the operating state of each of these places, a control lead wire is fed from each of the places to the controller C.C. P. Connected to A sampling nozzle 21 (FIGS. 3 and 4) for automatically traversing the diameter of the cross section of the powder pipe 1 which is a fuel supply pipe leading to the boiler, the structure of which will be described later, is installed. Thus, the powder may be sampled in real time by constant velocity suction adapted to the actual velocity distribution of the powder flow in the cross section of the powder tube 1, and then the powder may be analyzed. , The combustion conditions in the boiler (not shown) are adjusted based on the analysis result, and the powder tube 1
It is possible to change the type of powder supplied, the amount supplied, and the like.

[0010]

[Operation] The powder analysis sampling device according to the present invention is as follows.
Works like this. According to FIG. 2, the powder analysis test according to the present invention is performed.
The operation time chart of the charge collection device is shown. control
Device C. P. By pressing the start key of
C. P. In response to a command from the
The work cycle starts. Auto start after start
Off butterfly valve 6 time ΔT₁It is released after a while
After that, time ΔT₂Control valve 3 after the passage
Is released, resulting in ΔT₃Time (sampling time)
During this period, the powder will be sucked from the sampling tube.
It The automatic on / off butterfly valve 6 is opened by the above ΔT.
₃Before and after the predetermined time ΔT₂Start early and time ΔT
_FourEnds late, so ΔT₂+ ΔT₃+ ΔT_FourTemporal
The automatic on / off butterfly valve 6 is opened during
It is sucked, but at that time the opening time of the control valve 3
Is ΔT₃Collecting powder from the sampling nozzle 21 only during the time
The harvest is done. Next, the time ΔT₂+ ΔT₃+ ΔT_Fourof
After the automatic on / off butterfly valve 8 is opened
Air is discharged from the collector / dryer 7. This air
Is for drying the powder by the operation of the collector / dryer 7.
The purpose is to remove water and the like. This automatic on-off flap
The opening time of the fly valve 8 is the following time ΔT_Five+ ΔT₆(Dry
Drying time) + ΔT₈+ ΔT₉Is the sum of This time range
In other words, that is, the automatic on / off butterfly valve 8 is opened.
Time from release ΔT _FiveThis solenoid valve 12 is opened after
And time ΔT₆Compressed air is supplied from the solenoid valve 12 during
It This compressed air is made ΔT by the air heater 9._Five+ ΔT₆
Heated for (drying time). Added from the air heater 9
Heated compressed air takes time ΔT₆Used for collection / dryer 7
The supplied powder is dried. The thermocouple 13 is caught
The controller C. detects the ambient temperature in the collector / dryer 7 and detects the ambient temperature.
P. Communicate to. After the solenoid valve 12 is closed, it automatically turns on and off.
The butterfly valve 14 is opened and the time ΔT₇[Discharge
(Reduction) time] + ΔT₈The opening is maintained for a while. Therefore
Time ΔT₇[Discharge (reduction) time] + ΔT₈Collection / dry
The dry powder is dried when the dryer 7 outlet is opened.
It is supplied to the feeder 15. Time ΔT₇[When discharged (reduced)
Between] + ΔT₈Automatic on / off butterfly valve 1 after
7 is opened and the automatic on / off butterfly valve 17 is turned on.
It is opened for the interval ΔT and compressed air is sent to the ejector 19.
Get caught. This time ΔT is automatic on / off butterfly
Opening time of valve 18 ΔT_TenBefore (return time)
Later time ΔT₉And ΔT₁₁Time added with, ie time ΔT
₉+ ΔT_Ten+ ΔT₁₁Is. Therefore automatic on / off /
The open time of the butterfly valve 18 is ΔT_Ten(Return time)
Yes, during this time, the powder is powdered through the ejector 19.
Returned to tube 1. The flow and explanation of powder flow are mixed
However, the screw feeder 15 is automatically on / off / battery
When the lie valve 14 is opened, the operation starts at the same time and the automatic on
Before closing the butterfly valve 14 ΔT₈Stop at. Well
The rotary compressor 16 is an automatic on / off butterfly valve 14.
It operates at the same timing as the opening time of
Interval ΔT₇[Discharge (reduction) time] + ΔT₈Rotate for a while
Collect the powder in the cup. Time Δ after the rotation reducer 16 is stopped
T₉After that, the automatic on / off butterfly valve 18 is opened.
Released, and as described above, time ΔT_TenBetween powder powder tube
Allows a return to 1. The operating time of the air heater 9 is Δ
T_Five+ ΔT₆It's time.

The electromagnet M1 is excited for a time ΔT ₇ within the opening time of the automatic on-off butterfly valve 14, that is, starting from the opening of the automatic on-off butterfly valve 14 and starting the automatic on-off. Off butterfly valve 1
It is demagnetized before the closing time ΔT ₉ of 4. Therefore, time ΔT
_{During 7} the screw feeder 15 operates and then stops.
The electromagnet M2 is excited for a time ΔT ₇ + ΔT ₈ and demagnetized for a time ΔT ₉ before the opening of the automatic on / off butterfly valve 17. The rotation decompressor 16 rotates during excitation of the electromagnet M2, and stops when demagnetized. The operating time of the air heater 9 is between time ΔT ₅ + ΔT ₆ as described above,
The start time coincides with the opening time of the automatic on / off butterfly valve 8 and the closing time coincides with the excitation start time of the solenoid valve M2. Since the operation of the air heater 9 is premised on the opening of the automatic on / off butterfly valve 12, the above time ΔT ₅
During the time period ΔT ₆ between + ΔT _6, the air heater 9 is heated to send the compressed air to the trap / dryer 7.

Next, the important constitution of each part of the powder analysis sampling device will be described in detail. According to FIG. 3, the nozzle traverse device 2 comprises a sampling nozzle 21 entering the powder tube 1,
The sampling nozzle 21 is moved forward and backward along the diameter of the cross section of the powder tube 1 via a ball screw 24 as a feed screw driven by an induction motor 22 via a timing belt 23 and a spline 25. Slider 2 holding a tube 27 directly connected to 21
It consists of six. Since the end of the nozzle traverse device 2 is fixed to the outer surface of the powder tube 1, the induction motor 22
As described above, the sampling nozzle 21 can traverse the diameter of the cross section of the powder pipe 1 from one pipe inner wall a to the other pipe inner wall c through the pipe center b as described above. The traverse is normally performed by reciprocating between the inner wall a of one pipe and the inner wall c of the other opposite pipe, and the sampling can be performed in one way or both. As described above, the position and traverse speed of the nozzle traverse device 2 are controlled by the control device C. P. The position and traverse speed of the nozzle traverse device 2 are transmitted to the controller C.C. P. Is controlled via a control lead wire, and the traverse of the sampling nozzle 21 is normally performed at a variable speed according to the powder flow velocity distribution in the powder tube 1.

Changing the traverse speed at the time of sampling in accordance with the change in the concentration of the powder flow in the cross section of the powder tube 1 means that the powder analysis sampling takes a difference in speed between the inside and outside of the sampling nozzle 21 in the powder tube. Are required to be performed under the condition that As shown in FIG. 4, the static pressure on the inner wall of the sampling nozzle 21 is detected by the fluid pressure outlet pipe 29, and the static pressure outside the sampling nozzle 21 is detected by the fluid pressure outlet pipe 30, and the fluid pressure outlet pipe 29 is detected. And 30 are supplied to a common differential pressure gauge (not shown) and the differential pressure is measured, whereby the suction speed is adjusted to adjust the cross-sectional area of the control valve 3 of the nozzle traverse device 2 until the differential pressure becomes zero. When the differential pressure becomes zero, the static pressure inside and outside the sampling nozzle 21 becomes equal,
Therefore, the suction flow velocity in the sampling nozzle becomes equal to the flow velocity of the powder flow in the powder tube 1. If sampling is performed in this state, so-called constant velocity suction is achieved, and sampling corresponding to the velocity distribution in the cross section of the powder tube 1 is achieved.

In FIG. 4, the sampling nozzle 21 is connected to the pipe 27 in the nozzle traverse device 2, and the sampling nozzle 21 is connected to the control valve 3 as shown in FIG. Referring to FIG. 5, which shows the sampling nozzle 21 in more detail in conjunction with FIG. 4, purge pipes 31, 32 of similar diameter are disposed alongside the fluid pressure outlet pipes 29, 30 for outlet of static pressure. These purge pipes are respectively connected to a purge set, and the purge air is constantly supplied to the suction ports of the fluid pressure outlet pipes 29 and 30 of the sampling nozzle 21 to continuously supply the fluid pressure outlet pipes 29 and 30. Thirty
Helps ensure proper pressure control at. The purge pipes connected to the fluid pressure outlet pipes 29 and 30 by branch pipes are useful for cleaning the fluid pressure outlet pipes 29 and 30 when not collecting.

[Brief description of drawings]

FIG. 1 is a diagram showing an overall configuration of a powder analysis sampling device according to the present invention.

FIG. 2 shows an operation time chart of the powder analysis sampling device according to the present invention.

FIG. 3 is a detailed view of a nozzle traverse device used in the powder analysis sampling device according to the present invention, FIG. 3A being a view seen from the axial direction of the powder tube, and FIG. It is the figure seen from the radial direction.

FIG. 4 is a view showing the arrangement of measurement tubes and purge tubes attached to a sampling nozzle of the powder analysis sample sampling apparatus according to the present invention.

FIG. 5 is a diagram showing details of a sampling nozzle of the powder analysis sampling device according to the present invention.

[Explanation of symbols]

 1 powder tube 2 nozzle traverse device 3 control valve 4 cyclone 5 air flow meter 6 automatic on / off butterfly valve 7 collector / dryer 8 automatic on / off butterfly valve 9 air heater 10 air flow meter 11 needle valve 12 Solenoid Valve 13 Thermocouple 14 Automatic On / Off Butterfly Valve 15 Screw Feeder 16 Rotary Reducer 17 Automatic On / Off Butterfly Valve 18 Automatic On / Off Butterfly Valve 19 Ejector 21 Intake Nozzle 22 Induction Motor 23 Timing Belt 24 Ball screw 25 Spline 26 Slider 27 Pipe 29 Fluid pressure derivation pipe 30 Fluid pressure derivation pipe 31 Purge pipe 32 Purge pipe

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Satoshi Sugawara 1 Maejima, Daigasakihama, Shichigahama-cho, Miyagi-gun, Miyagi Prefecture Tohoku Electric Power Co., Inc. Sendai Thermal Power Plant (72) Tetsuo Ono 2-6, Nagasaka, Yokosuka City, Kanagawa Prefecture No. 1 Central Research Institute of Electric Power Industry Yokosuka Research Institute (72) Inventor Hirofumi Tsuji 2-6-1 Nagasaka, Yokosuka City, Kanagawa Prefecture Central Research Institute of Electric Power Industry Yokosuka Research Institute (72) Inventor Kazuo Saito Atsugi Kanagawa Prefecture 9-1 Mita City, Sankyo Piotech Co., Ltd. Atsugi Plant (72) Inventor, Kimihiro Hong 9-1 Mita, Atsugi City, Kanagawa Sankyo Piotech Co., Ltd. Atsugi Plant

Claims (8)

[Claims] 1. A sampling nozzle (21) is traversed or reciprocated on the diameter of the cross section of the powder pipe (1) from one pipe inner wall (a) to the center (b) to the other pipe inner wall (c). A method of collecting a powder analysis sample, which comprises traversing and adjusting a suction amount so that air velocities inside and outside of a sampling nozzle (21) are equal to each other. 2. A sampling nozzle by detecting the fluid pressure outside the sampling nozzle (21) and the fluid pressure inside the sampling nozzle (21) and adjusting the suction amount of the sampling nozzle (21) so that both fluid pressures become equal. The method for collecting a powder analysis sample according to claim 1, wherein the air velocities inside and outside (21) are made equal. 3. The powder according to claim 1, wherein a part of the collected powder is used as an analytical sample, and the remaining collected sample is returned to the powder pipe (1) in front of the sampling nozzle (21). Method of collecting analytical sample. 4. A sampling nozzle (21) mounted on the powder tube (1) and having fluid pressure outlet tubes (29, 30) inside and outside the suction nozzle is provided with a cross section of the powder tube (1). Nozzle traverse device (2) that drives on the diameter from the inner wall of one pipe to the inner wall of the other pipe at a constant speed or a variable speed
A conduit control valve (3) connected to the sampling nozzle (21) and the fluid pressure outlet pipe (29, 3).
0), the control device (CP) adjusts the opening of the control valve (3) so that the fluid pressures on the outside and inside of the sampling nozzle (21) become equal. Sampling device for powder analysis samples. 5. The powder according to claim 4, wherein the conduit via the control valve (3) has a cyclone (4) that separates and collects the powder by centrifugal force using the collected powder fluid as a swirling flow. Analytical sample collection device. 6. The powder analysis sample collecting device according to claim 5, further comprising a rotary contractor (16) for distributing the sample separated and collected by the cyclone (4) to a container as a required amount analysis sample. 7. The powder analysis sample collecting device according to claim 6, wherein the collected sample separated and collected by the cyclone (4) is distributed by the rotary contractor (16) after the heated fluid is blown and dried. . 8. A collected sample other than the sample which is connected to the powder tube (1) in front of the collecting nozzle (21) and is stored in a container as an analytical sample by the rotary contractor (16) is powdered. The powder analysis sample sampling device according to claim 6 or 7, further comprising an ejector (19) for transporting the sample into the pipe (1).