JP2001336706A - Temperature reducer for drain pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an excellent temperature reducer which can efficiently mix sprayed water with a high-temperature drain and has a simple structure and a high degree of freedom for installation location. SOLUTION: This temperature reducer is provided with a plurality of water spray nozzles having ejectros in a drain pipe into which the high-temperature drain is discharged from a blow tank and lowers the temperature of the drain by spraying water from the ejectors upon the drain flowing through the drain pipe, the water spray nozzles are composed of circular pipes each having a sealed front end and many ejectors bored at intervals in the axial direction of the pipe and are installed in such a way that the nozzles are fixed after the nozzles are passed through the drain pipe.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a drain pipe through which high-temperature water drain discharged from a boiler, a heat exchanger or the like flows in a thermal power plant, a chemical plant, or the like, or the high-temperature water drain is once collected in a blow tank. The present invention relates to a temperature reducer provided in a drain pipe through which high-temperature water discharged from a container flows.

[0002]

2. Description of the Related Art In a thermal power plant, high-temperature drain generated at the time of starting a boiler is collected in a blow tank, discharged to a drain tank after the temperature is reduced by a temperature reducer. The high-temperature drain in the blow tank communicates with the atmospheric pressure, and in normal operation,
It is 50C to 350C. In addition, high-temperature drainage from the blow tank to the drainage tank is performed through a drain pipe through a head difference between the blow tank and the drainage tank (typically 40 m
), And water is not forcibly sent by installing a pump especially in the middle of the drain pipe. If the temperature reducing device provided in the middle of the drain pipe cannot sufficiently lower the temperature, the high temperature water flows into the drain tank, and the drain tank is burned. Further, the water flows backward from the drainage tank to another device, which hinders the operation of the other device. Therefore, a cooler for the drain pipe of the blow tank requires a cooler having an excellent cooling effect.

[0003] As an example of the prior art, a conventional cooler for a drain pipe of a blow tank of a thermal power plant will be described with reference to Figs. The examples of the prior art shown in FIGS. 3 and 4 are all examples of a desuperheater devised to efficiently lower the temperature of the high-temperature water drain.

In these figures, reference numeral 1 denotes a drain tank 1 for storing a high-temperature water drain D from a boiler. The high-temperature water drain D is discharged from the drain tank 1 to a drain tank 6 through a drain pipe 2. Reference numeral 5 denotes a temperature reducer provided in the drain pipe 2, and a spray water pipe 7 is connected to the temperature reducer 5. High-pressure spray water is injected into the high-temperature water drain from an injection port 9 provided in a spray injection nozzle 10 of the temperature reducer 5 to lower the temperature of the high-temperature water drain D. Reference numeral 3 denotes a thermocouple provided downstream of the temperature reducer 5 of the drain pipe 2, and a signal from the thermocouple 3 is input to a spray control valve 4 provided in the spray water pipe 7, The temperature of the high-temperature water drain D flowing into the drainage tank 6 is controlled by adjusting the flow rate of the spray water S to the drain 5.

A desuperheater 5 shown in FIG. 3 is an example of a desuperheater used in a conventional thermal power plant. A jacket portion 12 forming a double pipe in a straight pipe portion of the drain pipe 2
And a spray water pipe 7 is connected from the outside to this, and a plurality of injection ports 9 are provided in the inner pipe side (drain pipe 2) of the double pipe in the circumferential direction. A screw mechanism 11 is provided on the inner surface of the drain pipe 2 from the double pipe section to the downstream side, and the screw mechanism 11 applies a turning force to the high-temperature water drain D. When the high-pressure spray water S is injected into the high-temperature water drain D from the injection port 9, the high-temperature water drain D generates a swirling force due to a reaction received from the screw mechanism 11 and forms a vortex turbulent flow. S is stirred and immediately mixed with the high-temperature water drain D, and the temperature is made uniform.

The conventional temperature reducer has a complicated structure in which a double pipe structure is formed from the outside and a screw mechanism 11 for forcibly generating turbulent flow is provided. Part, and high-temperature water drain D
Depending on the combination of the temperature and flow conditions of the spray water S and the spray water S, it is necessary to provide the screw mechanism 11 over a considerable length in order to achieve sufficient mixing.

[0007] The temperature reducer 5 shown in FIG.
The temperature reducer 5 is provided in a curved pipe portion 2a of the drain pipe 2 which generates turbulent flow, and a plurality of outward spray water S injection ports 9 are provided in a circumferential direction. By forming the inner pipe 8 of the extension of the spray water pipe 7 as a double pipe inserted into the drain pipe 2, the temperature of the high-temperature water drain D is efficiently reduced.

According to this configuration, the spray water S dispersed and injected into the high-temperature water drain D of the drain pipe curved tube portion 2a is sprayed.
Since the mixing with the high-temperature water drain D is promoted by the turbulence of the high-temperature water drain D generated in the curved pipe portion 2a, the high-temperature water drain D can be effectively cooled.

However, in the case of the temperature reducer 5, there is a restriction on the arrangement that the installation place is limited to the curved pipe portion 2a, and the spray water pipe 7 and the inner pipe 8 having a plurality of injection ports 9 are provided. It is necessary to fit to the curved pipe section 2a, which is disadvantageous in actual plant equipment, layout design and manufacture.

However, in consideration of adoption in a thermal power plant, the structure is simpler and the degree of freedom in selecting an installation place is reduced so as not to be disadvantageous due to structural complexity and restrictions on the installation place. The higher is also a further technical challenge required of the desuperheater.

[0011]

SUMMARY OF THE INVENTION In view of the above problems, the present invention is an excellent temperature reducer capable of efficiently mixing spray water with a high-temperature water drain and making the temperature uniform, and has a simple structure. An object of the present invention is to provide a temperature reducer having a high degree of freedom in selecting an installation place.

[0012]

Therefore, as a means for solving the above-mentioned problems, the present invention provides a drain pipe desuperheater described in each of the claims.

According to the first aspect of the present invention, a spray water injection nozzle having an injection port is provided in a drain pipe for discharging a high-temperature water drain from a blow tank to a high-temperature water flowing through the drain pipe. In a temperature reducer of a drain pipe that injects spray water from an injection port to lower the temperature of the high-temperature water, a spray water injection nozzle has a plurality of injection holes that are sealed at the tip and that are bored at intervals in the axial direction. A plurality of spray water injection nozzles having a large number of injection ports are provided at intervals along an axial direction of the drain pipe.

According to the drain pipe temperature reducer of the present invention, the spray water is sprayed at once from the many spray water injection holes formed in the spray water injection nozzle over the entire inner diameter of the drain pipe. Therefore, spray water is injected into the entire high-temperature water drain that passes over the entire length of the spray water injection nozzle.

The flow of the high-temperature water drain is turbulent in the downstream part of the spray water injection nozzle, and the injected and injected spray water is immediately stirred by the high-temperature water Mixing with drain and uniform temperature are promoted.

By disposing a plurality of spray water injection nozzles having such an operation effect at intervals in the axial direction of the drain pipe, it is possible to inject a considerable amount of spray water at the same time. As a result, the temperature of the high-temperature water drain can be significantly reduced, and the high-temperature water drain increases the agitating action of the vortex turbulence each time it passes through the spray water injection nozzle on the downstream side, which promotes mixing. ,
The distance until the high-temperature water drain and the spray water are uniformly mixed can be shortened.

According to a second aspect of the present invention, in the first aspect of the present invention, the plurality of spray water injection nozzles cross the drain pipe at a right angle to the direction of the flow of the high-temperature water flowing in the drain pipe. It is characterized by being fixed through and installed.

According to the drain pipe cooler of the present invention, in addition to the function and effect of the first aspect, the flow of the high-temperature water drain always crosses the spray water injection nozzle almost at right angles. This makes it easy to evaluate the fluid force of the high-temperature water drain acting on the entire length of the spray water injection nozzle.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the central axes of the plurality of spray water injection nozzles adjacent to the plurality of spray water injection nozzles are oriented in directions of twisting positions with respect to each other. It is characterized by being arranged.

According to the drain pipe cooler of the present invention, the effective hydraulic cross-sectional area in which the flow of the high-temperature water drain flowing in the drain pipe interferes with the spray water injection nozzle is maximized, and the generation of eddy turbulence is reduced. Most active. This maximizes the stirring effect due to the vortex turbulence generated in the downstream part of the spray water injection nozzle, and further promotes the mixing of the high-temperature water drain and the spray water as compared with the first and second aspects of the invention. This has the effect of further shortening the distance until the hot water drain and spray water are uniformly mixed.

According to a fourth aspect of the present invention, in the first aspect of the present invention, a large number of injection ports provided in the spray water injection nozzle are provided with a high-temperature water flow flowing through a drain pipe. And is provided on the rear side of the vehicle.

According to the drain pipe desuperheater constituting the present invention, a large number of injection ports provided in the spray water injection nozzle are provided behind the high-temperature water flow flowing through the drain pipe. By spraying the spray water into a negative pressure region generated behind the spray water spray nozzle, the mixing of the high-temperature water drain and the spray water and the uniform temperature as compared with the first to third aspects of the present invention. Is more promoted,
This has the effect of shortening the distance until the high-temperature water drain and spray water are uniformly mixed. Further, since the spray water is sprayed into the negative pressure region, the spray water is sprayed with low resistance due to the suction effect of the negative pressure.

According to a fifth aspect of the present invention, in the first aspect of the present invention, a large number of injection ports provided in the spray water injection nozzle are provided with a high-temperature water flow flowing through a drain pipe. Characterized in that it is provided on the side opposite to.

According to the drain pipe desuperheater constituting the present invention, the spray water injected toward the flow of the high-temperature water drain diffuses in a flared manner, so that the spray water is mixed with the high-temperature water drain simultaneously with the injection. At the beginning, the mixing is further accelerated by the stirring effect of the vortex turbulence generated behind the spray water injection nozzle. Therefore, as compared with the first to fourth aspects of the present invention, the mixing of the high-temperature water drain and the spray water and the temperature uniformization are further promoted, and the distance until the high-temperature water drain and the spray water are uniformly mixed. Has the effect of shortening.

[0025]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a drain pipe desuperheater according to an embodiment of the present invention. However, the components, dimensions, arrangement, fixing method, and the like described in this embodiment are not intended to limit the scope of the present invention, but are merely examples, unless otherwise specified.

FIGS. 1A and 1B show a drain tube temperature reducer according to a first embodiment of the present invention, wherein FIG. 1A is a longitudinal sectional view thereof, and FIG.
FIG. 2 is a cross-sectional view taken along line XX of (a), FIG. 2 shows the desuperheater of the second embodiment of the present invention, (a) is a longitudinal cross-sectional view, and (b) is It is sectional drawing by the YY line of (a).

In the temperature reducer 5 according to the first embodiment of the present invention shown in FIGS. 1 (a) and 1 (b), the spray water injection nozzle 10 has a sealed tip and is spaced in a line in the axial direction. And the axis of the spray water injection nozzle 10 is perpendicular to the direction of the flow of the high-temperature water drain D flowing through the drain pipe 2. At a position orthogonal to the axis 2, it is fixed by fillet welding through the drain pipe 2. And FIG.
As shown in (a), three spray water injection nozzles 10 are installed in parallel with each other at equal intervals in the axial direction of the drain pipe.

The spray port 9 of the spray water spray nozzle 10 is
The hot water drain D flowing in the drain pipe 2 is provided on the rear side with respect to the flow.

The number of the spray water injection nozzles 10 and the number of the injection holes 9 formed therein are determined based on the temperature condition and flow rate condition of the high-temperature water drain D, the diameter of the drain pipe 2, the spray Along with the diameter of the water injection nozzle 10, the diameter of the injection port 9, and the like, it is determined as a design item.

Further, the drain pipe 2 having a length within a range where the spray water injection nozzle 10 is installed is divided,
A unit in which the spray water injection nozzle 10 is installed and fixed in the factory in advance is prepared as a unit, and the unit is carried into the plant site, where the drain pipe 2 and the spray pipe 1 on the plant side are prepared.
3 may be connected and fixed.

According to the temperature reducer 5 of the first embodiment, the spray water is sprayed at once from the large number of spray water injection ports 9 formed in the spray water injection nozzle 10 over the entire inner diameter of the drain pipe 2. Since the water S is injected, the spray water S is injected into the entire high-temperature water drain D passing over the entire length of the spray water injection nozzle 10.

The flow of the high-temperature water drain D is in a negative pressure region and a vortex turbulence in the downstream part of the spray water injection nozzle 10, and the spray water S injected and injected immediately flows into the vortex turbulence. , The mixing with the high-temperature water drain D and the temperature uniformization are promoted. Further, since the spray water is sprayed into the negative pressure region, the spray water is sprayed with low resistance due to the suction effect of the negative pressure.

Since a plurality of spray water jet nozzles 10 having such an operation and effect are arranged at intervals in the axial direction of the drain pipe 2, a considerable amount of spray water S can be injected at the same time. In addition, since the high-temperature water drain D passes through the spray water injection nozzle 10 on the downstream side, the agitating action of the vortex turbulence increases, and the mixing is further promoted. You can
At the same time, it is expected that the distance until the high-temperature water drain and the spray water are uniformly mixed will be shorter.

In the temperature reducer 5 of the first embodiment, the axes of the spray water injection nozzles 10 are parallel to each other and orthogonal to the axis of the drain pipe.
Of the fluid load and thermal stress applied to the drain pipe 2 and the spray injection nozzle 10 can be simplified or simplified in consideration of the symmetry of the geometrical figure. , And simple operations such as repeatedly fixing the fillet welding of the spray water injection nozzle 10 are advantageous, which is advantageous in design and manufacture.

In the temperature reducer 5 of the second embodiment of the present invention shown in FIGS. 2A and 2B, the structure of each of the spray injection nozzles 10 is the same as that of the first embodiment. The spray water injection nozzle 10 is a high-temperature water drain that flows through the drain pipe 2 and is formed of a circular pipe having a tip sealed and a large number of injection ports 9 formed in a row in the axial direction. At a position where the axis of the spray water injection nozzle 10 is orthogonal to the axis of the drain pipe 2 so as to be orthogonal to the direction of the flow of D, the spray water injection nozzle 10 is fixed and installed by fillet welding through the drain pipe 2. I have. However, as can be seen from FIGS. 2 (a) and 2 (b), in the temperature reducer of the second embodiment, the three spray water injection nozzles 10 are spaced apart from each other at equal intervals in the axial direction of the drain pipe. It is installed at a twist position shifted by 90.

The spray port 9 of the spray water spray nozzle 10 is
Like the first embodiment, the hot water drain D flowing in the drain pipe 2 is provided on the rear side.

As in the first embodiment, the number of spray water injection nozzles 10 and the number of injection holes 9 formed in the nozzles are not limited to the example shown in FIG.

According to the desuperheater 5 of the second embodiment, similarly to the first embodiment, a large number of spray water injection ports 9 formed in the spray water injection nozzle 10 are used to connect the inside of the drain pipe 2 to the inside of the drain pipe 2. Because the spray water S is sprayed all at once over the entire inner diameter of
The spray water S is injected into the entire high-temperature water drain D passing over the entire length of the spray water injection nozzle 10.

The flow of the high-temperature water drain D is vortex turbulent in the downstream part of the spray water injection nozzle 10, and the spray water S injected and injected immediately agitates the vortex turbulence. By the action, mixing with the high-temperature water drain D and temperature uniformization are promoted.

Further, since a plurality of spray water jet nozzles 10 having such an operation and effect are arranged at intervals in the axial direction of the drain pipe 2, a considerable amount of spray water S is simultaneously injected. In addition, the hot water drain D increases the stirring effect of the vortex turbulence every time it passes through the spray water injection nozzle 10 on the downstream side, and the mixing is further promoted. Reduction can be achieved, and at the same time, the effect of shortening the distance until the high-temperature water drain and spray water are uniformly mixed is produced.

Further, according to the temperature reducer 5 of the second embodiment, the spray water injection nozzles 10 are installed at twisted positions shifted from each other by 90, and the high-temperature water drain flowing through the drain pipe 2 is formed. The flow of D is the spray water injection nozzle 1
The effective hydraulic diameter that interferes with zero is maximized, and vortex turbulence is most active. For this reason, the agitating action due to the vortex turbulence generated in the downstream part of the spray water injection nozzle 10 is maximized, and compared with the above-described temperature reducer 5 of the second embodiment of the present invention.
The mixing of the high-temperature water drain D and the spray water S is further promoted, and the effect of further shortening the distance until the high-temperature water drain D and the spray water S are uniformly mixed is produced. The angle of the twist position is not limited to 90 °, but may be another angle.

The temperature reducer 5 of the second embodiment also has structural symmetry and repetition of the same shape, and has a structure advantageous in design and manufacture as in the first embodiment. .

In both the first embodiment and the second embodiment of the present invention, the injection port 9 of the spray water injection nozzle 10 is used.
Has been provided on the back side with respect to the flow of the high-temperature water drain D flowing in the drain pipe 2. However, a large number of injection ports provided in the spray water injection nozzle are provided with respect to the high-temperature water flow flowing in the drain pipe. It may be provided on the opposite side.

In this case, since the spray water S injected toward the flow of the high-temperature water drain D is diffused in a flare state,
The spray water S starts to mix with the high-temperature water drain D at the same time as the spraying, and immediately thereafter, the mixing and temperature uniformization are further accelerated by the stirring action of the vortex turbulence generated immediately behind the spray water spray nozzle 10. . By such an action, the mixing of the high-temperature water drain and the spray water and the temperature uniformization are further promoted as compared with the first and second embodiments of the present invention, and the high-temperature water drain and the spray The effect of further shortening the distance until water is uniformly mixed is expected.

In each of the examples illustrated in this embodiment, the example in which the spray injection nozzle 10 is installed in the straight pipe portion of the drain pipe 2 has been described. The nozzle 10 is a simple circular pipe, and a large number of nozzles having the same shape, in which a number of spray water injection ports 9 are previously drilled, are used. 2, it is possible to exhibit the same function as in the first and second embodiments. For this reason, difficulties in designing and manufacturing are hardly considered.

[0046]

According to the drain pipe temperature reducer of the present invention, the high temperature water drain can be effectively mixed with the cooling water in a short time and a short distance in the drain pipe, and the temperature can be reduced. In addition, a uniform temperature of the waste water can be effectively achieved, and the structure is simple, so that there is a high degree of freedom in selecting an installation location, which is advantageous in design and manufacture.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a schematic structure of a drain pipe temperature reducer according to a first embodiment of the present invention (a), a cross-sectional view taken along a plane along the drain pipe (b), and a spray water injection nozzle. FIG. 3 is a cross-sectional view when cut along a plane that passes through and is orthogonal to the drain pipe.

FIG. 2 shows a schematic structure of a drain pipe desuperheater according to a second embodiment of the present invention (a), a cross-sectional view cut along a surface along the drain pipe (b), and a spray water injection nozzle. FIG. 3 is a cross-sectional view when cut along a plane that passes through and is orthogonal to the drain pipe.

FIGS. 3A and 3B show a high-temperature water drain system including a temperature reducer of a conventional thermal power plant, and FIG.

FIGS. 4A and 4B show a high-temperature water drain system including another type of conventionally known desuperheater, and FIG.
It is sectional drawing.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Blow tank 2 ... Drain pipe 2a ... Curved pipe part 3 ... Thermocouple 4 ... Spray adjustment valve 5 ... Temperature reducer 6 ... Drain tank 7 ... Spray water pipe 8 ... Inner pipe 9 ... Injection port 10 ... Spray injection nozzle 11 ... Screw mechanism 12: Jacket part D: High-temperature water drain S: Spray water A: Spray water spray direction

Claims (5)

[Claims] A spray water injection nozzle having an injection port is provided in a drain pipe for discharging high temperature water drain from a blow tank from a blow tank, and spray water is injected from the injection port to high temperature water flowing in the drain pipe. A drain pipe cooler for injecting water to lower the temperature of the high-temperature water, wherein the spray water injection nozzle has a circular pipe having a number of injection holes formed at an end thereof and sealed at intervals in an axial direction. A plurality of the spray water injection nozzles having a large number of injection ports are fixedly installed through the drain pipe at intervals along an axial direction of the drain pipe. Cooler. 2. The method according to claim 1, wherein the plurality of spray water spray nozzles are fixedly installed through the drain pipe so as to cross at a right angle to a direction of a high-temperature water flow flowing through the drain pipe. The drain tube desuperheater according to claim 1. 3. The spray water injection nozzle according to claim 1, wherein the central axes of the spray water injection nozzles adjacent to the plurality of spray water injection nozzles are arranged in the directions of the twisted positions. Drain tube cooler. 4. The spray water injection nozzle according to claim 1, wherein a plurality of injection ports provided in the spray water injection nozzle are provided at a rear side with respect to a high-temperature water flow flowing through the drain pipe. The drain pipe desuperheater according to any one of the preceding claims. 5. The spray water injection nozzle according to claim 1, wherein a plurality of injection ports provided in said spray water injection nozzle are provided on a side facing a high-temperature water flow flowing through said drain pipe. The drain tube cooler according to any one of claims 1 to 6.