Blowing-out facility and blowing-out method

Abstract

To provide a blowing-out facility capable of removing rust in exhaust gas and efficiently discharging it to the atmosphere while suppressing discoloration.SOLUTION: One aspect of the present disclosure is a blowing-out facility for removing rust inside the piping of a boiler using gas, the blowing-out facility comprising a connection pipe having a connection port connected to the piping and a discharge port for discharging gas having passed through the inside of the connection pipe to the atmosphere, and a collection unit for collecting the rust discharged together with the gas from the discharge port.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a blowing out installation and a blowing out method. [Background technology]

[0002] In large boilers used in power plants, etc., a process called blowing out is performed to clean the inner surface of the pipes arranged inside the boiler with high-temperature, high-pressure steam in order to prevent foreign matter such as rust from entering the turbine to which the steam is supplied. A blowing-out steam treatment system equipped with a cooling tank is known as a device for performing blowing out (JP Patent Publication 2003-065502). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2003-065502 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the early stage of blowing out, rust in the pipes supplying steam to the turbine is discharged together with the steam, and the steam discharged into the atmosphere may turn reddish brown or the like. The blowing out steam treatment system described in Patent Document 1 includes a cooling tank at the discharge section that discharges the steam, and reduces the amount of steam discharged by liquefying part of the steam in the cooling tank and discharging the remainder from the cooling tank. However, if a cooling tank is provided at the discharge section that discharges the steam, the cooling tank may become a resistance (pressure loss) to the discharge of the steam, suppressing the discharge of the steam and reducing the efficiency of cleaning the inside of the pipes. If the cooling tank is enlarged to reduce the pressure loss, the blowing out equipment installed as a temporary facility may become larger, making installation and removal more complicated, and increasing the cost of cleaning the pipes.

[0005] In consideration of the above-mentioned circumstances, the present disclosure aims to provide a blowing-out facility that can remove rust from the exhausted gas and efficiently exhaust the gas into the atmosphere while suppressing discoloration. [Means for solving the problem]

[0006] One aspect of the present disclosure made to solve the above problems is a blowing-out facility for removing rust inside boiler piping using gas, the facility comprising: a connecting pipe having a connection port connected to the piping and an exhaust port for exhausting gas that has passed through the inside of the connecting pipe to the atmosphere; and a collection section for collecting the rust exhausted together with the gas from the exhaust port. Effect of the Invention

[0007] The blowing out equipment according to one embodiment of the present disclosure can efficiently discharge the exhausted gas into the atmosphere while removing rust from the exhausted gas and suppressing discoloration. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic side view showing a blowing-out facility according to an embodiment of the present disclosure and a boiler whose piping is cleaned by the blowing-out facility. [Diagram 2] FIG. 2 is a schematic enlarged plan view of the blowing-out facility of FIG. [Diagram 3] FIG. 3 is a schematic side view showing a test device in the examples. [Figure 4] FIG. 4 is a graph showing the test results of the examples. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] [Description of the embodiments of the present disclosure] First, the embodiments of the present disclosure will be listed and described.

[0010] (1) One aspect of the present disclosure is a blowing-out facility for removing rust inside a boiler pipe using a gas, the facility including a connecting pipe having a connection port connected to the pipe and an exhaust port for exhausting gas that has passed through the inside of the connecting pipe to the atmosphere, and a collection unit for collecting rust exhausted together with the gas from the exhaust port.

[0011] The blowing-out equipment includes a collection section that collects rust discharged together with the gas that cleans the inside of the boiler pipes. This makes it possible to reduce rust in the gas passing through the collection section, and to suppress discoloration of the gas discharged into the atmosphere. The collection section collects rust in the gas after it has been discharged into the atmosphere, and is unlikely to cause a pressure loss in the gas discharged from the pipes, so that the gas can be efficiently discharged into the atmosphere.

[0012] (2) In the above (1), the collection section may have a mesh member and a liquid supply device that supplies liquid to the mesh member. In this way, rust can be efficiently collected.

[0013] (3) In the above (2), the collection unit may be disposed above the outlet and further include a side wall erected on the ground or floor so as to surround the outlet and the mesh member. In this way, rust can be collected more efficiently.

[0014] (4) In the above (3), a gap may be formed between the ground or the floor and the side wall. That is, the side wall may be easily installed.

[0015] (5) In any one of (2) to (4) above, the upper part of the mesh member may be open by 80% or more in terms of area, thereby preventing a decrease in the efficiency of releasing the gas into the atmosphere.

[0016] (6) One aspect of the present disclosure is a blowing-out method for removing rust inside a pipe of a boiler by using a gas, the blowing-out method including the steps of: increasing the pressure of the gas inside the pipe; discharging the pressurized gas from an outlet of a connecting pipe connected to the pipe; and blowing out the gas together with the rust from the outlet. rust and collecting the same.

[0017] The blowing out method collects rust contained in the gas discharged from a connecting pipe connected to the boiler pipe, so that the rust in the gas can be reduced and discoloration of the gas discharged to the atmosphere can be suppressed. Moreover, the blowing out method is unlikely to cause pressure loss of the gas discharged from the pipe, so that the gas can be efficiently discharged to the atmosphere.

[0018] (7) In the above (6), in the collecting step, the gas discharged from the outlet may be passed through a mesh member to which a liquid is supplied. In this way, the rust can be collected efficiently.

[0019] (8) In the above (7), a step of guiding the gas discharged from the exhaust port to the mesh member may be further provided, whereby the rust can be more efficiently collected.

[0020] (9) In the above (8), in the guiding step, a side wall erected on the ground or floor so as to surround the mesh member may be used. In this way, the gas can be easily guided.

[0021] (10) In the above (9), a gap may be formed between the ground or floor and the side wall. That is, the side wall may be easily installed.

[0022] (11) In any one of (7) to (10) above, the upper part of the mesh member may be open by 80% or more in terms of area, thereby making it possible to suppress a decrease in the efficiency of releasing the gas into the atmosphere.

[0023] (12) In the above (9) or (10), a step of completing the gas discharge and removing the mesh member and the side wall may be further provided after the collecting step. That is, the mesh member and the side wall may be temporary members that can be easily installed and removed.

[0024] Here, "up" means the direction opposite to the direction of gravity.

[0025] [Details of the embodiment of the invention] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0026] <Blowing out equipment> 1 and 2, the blowing-out equipment 1 includes a connecting pipe 10 having a connecting port 11 connected to a piping P of a boiler B and an exhaust port 12 for discharging gas that has passed through the inside of the equipment to the atmosphere (outdoors), and a collection section 20 for collecting rust discharged together with the gas from the exhaust port 12. The blowing-out equipment 1 removes rust inside the piping P of the boiler B by using gas. The gas is not particularly limited, but is preferably one having a lower specific gravity than air, for example, steam (water vapor) obtained by vaporizing water.

[0027] The boiler B is not particularly limited, and may be, for example, one that is installed in a power plant and generates steam for rotating a turbine T. The boiler B has a pipe P for supplying steam to the turbine T. A part of the pipe P is disposed inside the body of the boiler B, and has a branch part P1 that branches off between the boiler B and the turbine T. The branch part P1 is provided with a connected port P2 that can be connected to a connecting port 11, and a valve V is disposed upstream of the connected port P2.

[0028] [Connecting pipe] The connecting pipe 10 has a connecting port 11 that is connected to the connected port P2 of the pipe P, and an exhaust port 12 that exhausts the gas to the atmosphere. A silencer S that reduces the volume of the gas when it is exhausted may be connected to the exhaust port 12. In this case, the outlet of the silencer S becomes the exhaust port 12, and the gas is released from the exhaust port 12 of the silencer S to the atmosphere.

[0029] [Collection section] The collection unit 20 collects rust discharged together with the gas from the exhaust port 12. The collection unit 20 is preferably disposed above the exhaust port 12. When a silencer S is connected to the exhaust port 12, the collection unit 20 should be disposed above the silencer S. In other words, it is preferable to dispose the collection unit above where the gas is discharged. In this way, the rust in the gas rising from the exhaust port 12 can be efficiently collected.

[0030] The collection section 20 preferably has a mesh member 21 and a liquid supply device 22 that supplies liquid to the mesh member 21. The liquid supply device 22 is preferably disposed above the mesh member 21. In this manner, the liquid can be efficiently supplied to the mesh member 21.

[0031] (Liquid supply device) The liquid supply device 22 supplies liquid to the mesh member 21. The liquid is not particularly limited, and water can be used, for example. The supply of liquid to the mesh member 21 is not particularly limited, but it is preferable to continuously spray the liquid onto the surface (upper surface) of the mesh member 21 so that the liquid is supplied substantially uniformly. In this way, the rust collection efficiency of the mesh member 21 can be improved.

[0032] In this embodiment, the liquid supply device 22 includes a water supply pipe 23 and a nozzle tip 24 that is disposed in the water supply pipe 23 and is capable of spraying the liquid in a mist form approximately uniformly over a predetermined range (area). A plurality of nozzle tips 24 are disposed in the water supply pipe 23 so as to supply the liquid in a mist form over the entire surface of the mesh member 21. The nozzle tip 24 is not particularly limited, but is preferably a full pyramidal nozzle.

[0033] (Mesh member) The mesh member 21 collects rust in the exhausted gas. The mesh member 21 is not particularly limited, but is preferably a wire mesh demister formed by weaving wires. The material of the wires is not particularly limited, but may be, for example, a metal.

[0034] The lower limit of the void ratio of the mesh member 21 is preferably 80%, more preferably 90%, and even more preferably 95%. The upper limit of the void ratio of the mesh member 21 is not particularly limited and may be, for example, 99%. By setting the void ratio of the mesh member 21 within the above range, the resistance (pressure loss) when gas passes through the mesh member 21 can be reduced, and the gas can be efficiently released to the atmosphere. Note that "void ratio" means the ratio of the volume of space per unit volume.

[0035] When liquid is supplied to the mesh member 21, a water film is formed on each of the wires. When gas passes through the mesh member 21 to which liquid has been supplied, some of the rust in the gas is captured by the water film on the wires. The rust captured in the water film on the wires falls from the mesh member 21 due to its own weight, the water film turning into droplets, etc. The gas discharged from the exhaust port 12 may be discolored, such as reddish brown, due to rust removed from the piping P. The mesh member 21 captures some of the rust in the gas passing through it, and therefore can reduce discoloration of the gas that passes through the mesh member 21 and is released into the atmosphere.

[0036] It is preferable that the upper part of the mesh member 21 is open by 80% or more on an area basis. That is, it is preferable that the open rate of the upper part of the mesh member 21 is 80% or more. In other words, it is preferable that the presence rate (area rate) of other members (for example, shielding objects such as a roof covering the mesh member 21) in the presence region (area) of the mesh member 21 in a plan view is less than 20%. Specifically, for example, in this embodiment, the water supply pipe 23 and the nozzle tip 24 of the liquid supply device 22 are arranged above the mesh member 21 (see FIG. 2). It is preferable that the area rate of the member arranged to shield the upper part of the mesh member 21, such as the liquid supply device 22, in a plan view is less than 20% of the area of ​​the mesh member 21. In this way, the pressure loss of the gas discharged to the atmosphere can be reduced, and the pipe P can be efficiently cleaned. The lower limit of the open rate of the mesh member 21 may be 85%, 90%, or 95%. The upper limit of the open rate of the mesh member 21 may be 100%.

[0037] (side wall) The blowing-out equipment 1 preferably includes a side wall 25 erected on the ground or floor so as to surround the exhaust port 12 and the mesh member 21. That is, the exhaust port 12 and the mesh member 21 are preferably arranged inside the side plate 25. In this way, the gas discharged from the exhaust port 12 can be guided to the mesh member 21, and the rust collection efficiency can be improved. The mesh member 21 may be configured to be attached to the side wall 25. Specifically, the side wall 25 may have a holding member for holding the mesh member 21, and the mesh member 21 may be attached to the side wall 25 by being held by the holding member.

[0038] A gap may be formed between the ground or floor (hereinafter also referred to as the installation surface G) and the side wall 25. That is, the side wall 25 may not be installed so that the lower end of the side wall 25 is completely in contact with the installation surface G, but may be simply installed so that a gap is formed. Also, if the side wall 25 is composed of a plurality of flat plate materials, some gap may be formed between adjacent flat plate materials. In this way, the side wall 25 can be easily installed and removed.

[0039] The side wall 25 is not particularly limited as long as it is a temporary facility that can be easily installed and removed, and may be formed, for example, by setting up a scaffolding that is temporarily assembled at the construction site around the discharge outlet 12 and leaning multiple scaffolding floor panels or multiple flat plate materials against the scaffolding.

[0040] (Bottom plate) The blowing-out equipment 1 preferably has a base plate 26 for collecting water droplets (which may contain rust) that have fallen from the mesh member 21. The base plate 26 is disposed on the installation surface G below the mesh member 21. The blowing-out equipment 1 more preferably has a communication section 27 that communicates the base plate 26 with a liquid collection section 30 that is provided at a position spaced apart from the collection section 20 and that stores the water droplets collected by the base plate 26. This allows the water droplets collected by the base plate 26 to be efficiently treated. The liquid collection section 30 preferably has a pump (not shown) disposed therein for supplying the water droplets collected by the base plate 26 to a water treatment facility (not shown) that treats the water droplets.

[0041] <Blowing out method> The blowing out method includes a step of increasing the pressure of the gas in the pipe P, a step of discharging the pressurized gas from an outlet 12 of a connecting pipe 10 connected to the pipe P, and a step of collecting the rust discharged together with the gas from the outlet 12.

[0042] [Step of increasing pressure] The step of increasing pressure increases the pressure of the gas in the pipe P. The means for increasing the pressure of the gas in the pipe P is not particularly limited, and for example, water may be supplied to the pipe P, the water may be heated in the boiler B to turn into steam, and the pressure of the steam may be increased. Specifically, water may be supplied to the pipe P, the flow path from the branch P1 to the turbine T may be blocked, and the valve V may be closed, and the pipe P may be heated in the boiler B to turn the supplied water into high-pressure steam.

[0043] [Discharging step] In the exhaust process, the pressurized gas is exhausted to the atmosphere from exhaust port 12 of connecting pipe 10 connected to piping P. Specifically, valve V disposed at branch point P1 of connecting pipe 10 connected to piping P is opened to exhaust the pressurized gas (high-pressure steam) from exhaust port 12 of connecting pipe 10 connected to piping P.

[0044] [Collection step] In the collection step, the rust discharged from the exhaust port 12 together with the gas is collected. That is, rust in the gas in the atmosphere (rust in the gas discharged outdoors) is collected. The collection of rust is performed by the collection unit 20. The collection unit 20 preferably has a mesh member 21 and a liquid supply device 22 that supplies liquid to the mesh member 21. The gas preferably passes through the mesh member 21 to which the liquid is supplied. The mesh member 21 is preferably disposed above the exhaust port 12, and removes a portion of the rust from the gas (water vapor) passing through. It is preferable that 80% or more of the upper part of the mesh member 21 is open on an area basis.

[0045] [Inducing step] The blowing out method may include a step of guiding the gas discharged from the exhaust port 12 to the mesh member 21. The gas is preferably guided using a side wall 25 erected on the ground or floor so as to surround the mesh member 21. Specifically, it is preferable to erect a side wall 25 surrounding the exhaust port 12 and the mesh member 21, and to perform the step of guiding the discharged gas to the mesh member 21 by the side wall 25 and collecting the gas. A gap may be formed between the installation surface G and the side wall 25.

[0046] [Removal process] The blowing out method may further include a step of completing the gas discharge and removing the mesh member 21 and the side wall 25 after the collecting step. Specifically, after all of the pressurized gas in the pipe P is discharged and the rust collection is completed, the arranged mesh member 21 and the side wall 25 installed to guide the gas to the mesh member 21 are removed. At the same time, it is preferable to remove the liquid supply device 22. In addition, the connection between the connecting pipe 10 and the pipe P is released, and the pipe P is connected to the turbine T. The blowing out equipment 1 is not used for anything other than cleaning the pipe P of the boiler B, so it is preferable to remove it.

[0047] <Advantages> The blowing-out equipment 1 includes a collector 20 for collecting rust discharged together with the gas from the outlet 12 of the connecting pipe 10, and therefore can reduce the amount of rust in the gas. Therefore, discoloration of the gas discharged into the atmosphere can be suppressed. The collector 20 of the blowing-out equipment 1 is not disposed in a structure such as a tank or a building, but is disposed so as to remove rust in the gas after it is discharged from the outlet 12 to the atmosphere (outdoors). In other words, the blowing-out equipment 1 does not discharge the gas from the outlet after removing the rust into the atmosphere, but removes rust from the gas after it is discharged from the outlet 12 to the atmosphere. Therefore, the blowing-out equipment 1 is unlikely to cause a pressure loss for the gas discharged from the outlet 12, and can efficiently discharge the gas in the connecting pipe 10 and the pipe P, and can efficiently clean the inside of the pipe P. In addition, the blowing-out equipment 1 does not require the above-mentioned structure for disposing the collector 20, and therefore has a simple configuration and can be easily installed and removed. Therefore, the blowing out can be performed easily at low cost while removing the rust in the gas. Since the blowing out method uses the blowing out equipment 1, the blowing out can be performed easily.

[0048] [Other embodiments] The above-mentioned embodiment does not limit the configuration of the present invention. Therefore, the above-mentioned embodiment may omit, replace or add components of each part of the above-mentioned embodiment based on the description in this specification and common technical knowledge, and it should be understood that all of these are within the scope of the present invention. EXAMPLES

[0049] The present disclosure will be further described below with reference to examples, but the present disclosure is not limited to these examples.

[0050] The rust removal effect in gas was confirmed using a test apparatus 100 as shown in Fig. 3. The test apparatus 100 includes a pipe 101, a compressor 102 that supplies compressed air to the pipe 101, a tank 103 that supplies powdered rust to the pipe 101, a casing 104 connected to the outlet of the pipe 101, a mesh member 105 disposed above the casing 104, and a liquid supply device disposed above the mesh member 105. The liquid supply device includes a nozzle tip 106 that sprays water almost uniformly onto the surface of the mesh member 105, and a water supply pipe 107 that supplies water to the nozzle tip 106.

[0051] A wire mesh demister with a thickness of 25 mm and a void ratio of 97.5% was used as the mesh member 105. A full pyramidal nozzle with a standard pressure of 0.2 MPa was used as the nozzle tip 106. The flow velocity of the air passing through the mesh member 105 was 3.8 m / s, which is equivalent to the gas flow velocity passing through the mesh member during actual blowing out.

[0052] The thickness of the mesh member 105 (the distance between the upper surface and the lower surface), the water spraying pattern to the mesh member 105, and the amount of water sprayed to the mesh member 105 were changed, and the rust capture rate of each mesh member 105 was compared. The capture rate was calculated as the ratio (mass ratio) of the total amount of rust attached to the mesh member 105 and the rust dropped to the bottom of the casing 104 to the amount of rust supplied from the tank 103 after each test. The results are shown in Table 1 and FIG. 4. In Table 1, the mesh member 105 having a thickness of 50 mm means that two mesh members 21 are stacked. "No water spraying" means that water was not sprayed by the liquid supply device, "pre-water spraying" means that water was sprayed and stopped before compressed air and rust were supplied into the casing 104, and "constant water spraying" means that water was sprayed continuously during the test. "Water spraying amount" means the amount of water sprayed during the test.

[0053] [Table 1]

[0054] Comparing Test Example 3 and Test Example 4 from Table 1 and Figure 4, it can be seen that there is no change in the capture rate even when the thickness of the mesh member 105 used in this test exceeds 25 mm. In other words, no improvement in the capture effect was confirmed even when two mesh members 105 with a thickness of 25 mm were stacked. It can also be seen that the capture rate was low without water spraying and with prior water spraying (Test Examples 1 and 2). The water spray rate was 0.22 L / min m 2 It can be seen that the capture efficiency does not improve even if the concentration exceeds this value. [Industrial Applicability]

[0055] The blowing-out equipment according to one embodiment of the present disclosure is particularly suitable for cleaning the pipes of large boilers, since it can suppress discoloration of the gas discharged from the cleaned pipes. [Explanation of symbols]

[0056] 1. Blowing out equipment 10 Connecting pipe 11 Connection port 12 Outlet 20 Collection section 21,105 Mesh members 22 Liquid supply device 23,107 Water supply pipes 24,106 Nozzle Tip 25 Side wall 26 Bottom plate 27 Communication part 30 Collection Department 100 Test Equipment 101 Pipe 102 Compressor 103 Tank 104 Casing B Boiler G Installation surface P piping P1 Branch P2 Connected port S silencer T Turbine V-Valve

Claims

1. A blowing-out facility for removing rust from inside boiler piping using gas, a connecting pipe having a connecting port connected to the piping and an exhaust port for exhausting gas that has passed through the inside of the connecting pipe to the atmosphere; a collection section for collecting rust discharged together with the gas from the exhaust port; A blowing out facility comprising:

2. 2. The blowing-out facility according to claim 1, wherein the collecting section comprises a mesh member and a liquid supply device for supplying liquid to the mesh member.

3. The collection section is disposed above the discharge port, 3. The blowing-out facility according to claim 2, further comprising a side wall erected on the ground or floor so as to surround the discharge port and the mesh member.

4. 4. The blowing out installation according to claim 3, wherein a gap is formed between the ground or floor and the side wall.

5. 5. The blowing out facility according to claim 2, 3 or 4, wherein 80% or more of the upper part of said mesh member is open in terms of area.

6. A blowing-out method for removing rust from inside a boiler pipe by gas, comprising the steps of: increasing the pressure of the gas in the pipe; Discharging the pressurized gas to the atmosphere from an outlet of a connecting pipe connected to the piping; collecting the rust discharged together with the gas from the exhaust port; A blowing out method comprising:

7. 7. The blowing out method according to claim 6, wherein in said collecting step, said gas discharged from said outlet is passed through a mesh member to which a liquid is supplied.

8. 8. The blowing out method according to claim 7, further comprising the step of directing the gas discharged from the outlet to the mesh member.

9. 9. The blowing out method according to claim 8, wherein the guiding step uses a side wall erected on the ground or floor so as to surround the net-like member.

10. The blowing out method of claim 9, wherein a gap is formed between the ground or floor and the sidewall.

11. 9. The blowing out method according to claim 7 or 8, wherein 80% or more of the upper part of the mesh member is opened in terms of area.

12. After the collection step, 11. The blowing out method according to claim 9 or 10, further comprising the step of removing the mesh member and the side wall upon completing the evacuation of the gas.

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