JPH116603A - Mist catcher - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mist catcher to be evenly separable throughout a range from large mist to small one, in mist catchers aligned through a plurality of spacers of a corrugated plate with a given distance kept therebetween. SOLUTION: A casing 6 of which a mist catcher is composed is provided with a top plate 1, a bottom plate 2, and side plates 3 on both the right and left sides, and an inlet 4 and an outlet 5 are opened at a front and a rear. Mist catchers are aligned in parallel to the both the right and left side plates 3 at intervals of a given distance through a plurality of spacers 8 of a corrugated plate 11 in the casing 6 in the shape of a rectangular parallelopiped. A bending angle α1-αn+1 of the corrugated plate 11 is increased as going downstream.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mist catcher applied to a steam boiler and an apparatus for handling a gas-liquid mixture similar to the steam boiler.

[0002]

2. Description of the Related Art An example of a conventional mist catcher is shown in FIG.
As shown in FIG. In these figures, a waveform is formed in a rectangular parallelepiped housing 6 having a top plate 1, a bottom plate 2, and side plates 3 on both left and right sides, and having an inlet 4 and an outlet 5 open front and back. A plurality of plates 7 are arranged in parallel with the left and right side plates 3 at a required interval from each other via a spacer 8.

[0003] These corrugated plates 7 are fixed by penetrating fastening bolts 9 and the like to form a separator main body 10.
Here, the bending angle α of the corrugated plate 7 is constant over the entire flow path from upstream to downstream.

FIG. 5 schematically shows a flow state in the corrugated plate 7 in the conventional mist catcher. To explain this, the gas-liquid flow a containing the mist b flows along the corrugated shape of the corrugated plate 7, but in the bent portion, the mist b collides with the corrugated plate 7 by the action of the generated centrifugal force,
The mist b after the collision flows down on the corrugated plate surface and flows on the bottom plate 2 in the downstream direction as shown in FIG.

In this manner, the mist b is separated from the gas-liquid flow a, and becomes a mist-free vapor flow c at the end of the corrugated plate 7. Here, the mist separation characteristics are greatly affected by the bending angle α of the corrugated plate 7.

[0006] In the case of a steam boiler, for example, in the case of a steam boiler, as shown in FIG. 6, two separator bodies 10 each include a drum 101 having an evaporation pipe 102, a downcomer 103, and a main steam pipe 104. The two separator bodies 10 are attached horizontally to the gas phase portion 105 of the inside of the container 10 via a water receiver 106 having a drain pipe 107.
Are connected by a closing plate 108.

[0007] The steam-water mixed fluid supplied into the drum 101 from the evaporating pipe 102 passes between the partition plate 109 provided in the drum 101 and the inner wall of the drum 101.
It flows down toward the water 110 in one.

[0008] The steam and retained water 110 flowing down
Vapor evaporates in the drum toward the separator body 10 of the mist catcher, and the mist is collected in the mist catcher. The collected mist becomes drain and passes through the drain pipe 107 to the water 110 in the drum 101. Will be returned.

The water 110 in the drum is returned from the downcomer 103 to a boiler inlet pipe (not shown). The steam after the mist separation is further heated through a main steam pipe 104, for example, by a heating pipe (not shown), and then sent to a turbine. The mist separation performance by the corrugated plate is generally represented by the following equation.

[0010]

(Equation 1)

[0011]

In the mist catcher according to the prior art shown in FIGS. 3 and 4, since the wave bending angle α of the corrugated plate 7 is uniform over the entire upstream to downstream flow path, the mist diameter d is small. If it is smaller than expected, there is a problem that a sufficient mist separation efficiency η cannot be achieved. Note that η is 1.0 when the mist is completely separated.

According to the present invention, there is provided a mist catcher in which a plurality of corrugated plates are arranged at a predetermined interval from each other via a spacer so that a mist having a large diameter and a mist having a small diameter can be uniformly separated. The task is to provide a catcher.

[0013]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a mist catcher which employs a corrugated plate whose bending angle is increased toward the downstream side.

In the mist catcher according to the present invention, the bending angle of the corrugated plate is formed larger as it goes downstream, so that the downstream side having a large bending angle on the downstream side, as is apparent from the above equation (1). In this case, mist having a small diameter can be separated well. As described above, according to the mist catcher of the present invention, mist having a large diameter to a small diameter can be uniformly separated.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to FIGS. This embodiment is also applied to a mist catcher in a drum of a steam boiler, and the same components as those of the conventional apparatus shown in FIGS. 3 to 6 are denoted by the same reference numerals for simplification of description.

A separator main body 10 in the mist catcher shown in FIGS. 1 and 2 has a top plate 1, a bottom plate 2, left and right side plates 3, and has an inlet 4 and an outlet 5 in front and back. A plurality of corrugated plates 11 whose bending angles continuously change from the upstream side to the downstream side are placed in a rectangular parallelepiped housing 6 in parallel with the right and left side plates 3 at a required interval via a spacer 8. The corrugated plates 11 are arranged in a row and fixed by fastening bolts 9 that penetrate these corrugated plates 11.

The other configuration of the present embodiment is substantially the same as the configuration of the conventional mist catcher shown in FIGS. 3 to 6, and the description is omitted.

In the embodiment shown in FIGS. 1 and 2, the bending angle of the corrugated plate 11 changes continuously from the upstream side α1 to the downstream side αn + 1. Where α1 <
If α2... <αn <αn + 1, the mist diameter that can be separated becomes smaller as approaching the downstream side from Equation (1) above (when the separation efficiency η is constant). That is, in the mist catcher of the present embodiment, the separation mist diameter is different between the upstream side and the downstream side.

In the present embodiment having the above-described configuration, the corrugated plate 11 is provided in which the bending angle of the waveform changes so as to gradually increase from the upstream side to the downstream side, and the mist separation functions over a wide mist diameter. Therefore, even if a mist having a small diameter that is not expected at the time of planning flows in, the mist separation characteristics do not deteriorate.

Here, the bending angle is determined by using the equation (1) so as to cover the actual operation conditions.

For example, in the related art, since the bending angle α of the corrugated plate is constant at 10 °, the minimum mist diameter that can be collected by the corrugated plate is constant at 0.0294 mm. Applying the present invention, the bending angle α of the corrugated plate is set to 1 at the most upstream side.
Assuming 0 ° and 120 ° at the most downstream side, the minimum mist diameter collected by the corrugated plate is 0.0294 mm to 0.0085 mm
Changes to

In the prior art, the bending angle α of the corrugated plate is set to 1
Assuming a constant 20 °, the minimum mist diameter collected by the corrugated plate can be 0.0085 mm, which is the same as in the case of the present invention, but from the large-diameter mist to the mist having a diameter of 0.0085 mm in the most upstream corrugated plate. A large amount of mist is collected.

In this case, as shown in FIG. 3, the entire amount of the mist b flows down on the corrugated plate, so that the mist b is raised by the gas-liquid flow a flowing between the corrugated plates. Deteriorates.

In the present invention, a thin and uniform falling film of mist b can be formed on the entire surface of the corrugated plate by continuously changing the bending angle α of the corrugated plate in the flow direction.
Therefore, according to the present invention, the mist b is not wound up by the gas-liquid flow a generated in the prior art.

Although the present invention has been specifically described based on the illustrated embodiment, the present invention is not limited to this.
It goes without saying that various changes can be made to the specific structure and configuration within the scope of the present invention.

[0026]

As described above, according to the present invention, a plurality of corrugated plates are provided in a rectangular parallelepiped housing having a top plate, a bottom plate, left and right side plates, and having an inlet and an outlet opening in front and back. In a mist catcher which is arranged in parallel with the left and right side plates at a required distance from each other via a spacer, the bending angle of the corrugated plate is formed to be larger toward the downstream side, and the waveform in which the bending angle changes Plates can evenly separate large-diameter mist to small-diameter mist.

As a result, in the mist catcher of the present invention, the operating range in which high-performance mist separation can be achieved is wider than in the case of applying the prior art, and, for example, the mist catcher is sent to the turbine even under operating conditions that were not initially expected. It is possible to reduce the amount of mist contained in the steam.

As a result, the amount of impurities such as silica contained in the mist, which adhere to the turbine blade surface, is reduced, so that the turbine life can be prolonged or the maintenance cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a drawing showing a configuration of a mist catcher according to an embodiment of the present invention, wherein (a) is a plan view, (b) is a side view, and (c) is an end view.

FIGS. 2A and 2B are diagrams showing a configuration of a corrugated plate employed in the mist catcher shown in FIG. 1, wherein FIG. 2A is an upstream sectional view and FIG. 2B is a downstream sectional view.

FIG. 3 is a drawing showing a configuration of a conventional mist catcher;
(A) is a plan view, (b) is a side view, and (c) is an end view.

4A and 4B are diagrams showing a configuration of a corrugated plate employed in the mist catcher shown in FIG. 3, wherein FIG. 4A is a sectional view on the upstream side and FIG. 4B is a sectional view on the downstream side.

5A and 5B are drawings for explaining the mist separating action of the corrugated plate of the mist catcher, wherein FIG. 5A is a cross-sectional view and FIG.
Is a perspective view.

FIG. 6 is a sectional view showing a structural example of a steam separator in a steam boiler.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Top plate 2 Bottom plate 3 Side plate 4 Inlet 5 Outlet 6 Case 7 Corrugated plate 8 Spacer 9 Tightening bolt 10 Separator main body 11 Corrugated plate 101 Drum 102 Evaporation pipe 103 Downcomer 104 Main steam pipe 105 Gas phase 106 Water receiver 107 Drain Pipe 108 Blocking plate 109 Partition plate 110 Water in drum

Claims (1)

[Claims] 1. A plurality of corrugated plates having a top plate, a bottom plate, left and right side plates, and a plurality of corrugated plates disposed at predetermined intervals via spacers in a rectangular parallelepiped-shaped housing having an inlet and an outlet opening in front and back. A mist catcher arranged in parallel with the left and right side plates, wherein a bending angle of the corrugated plate is increased toward a downstream side.