JPH05172304A - Clean superheated steam generator - Google Patents

Abstract

PURPOSE:To obtain a clean superheated steam generator integrated with a steam generator and a steam superheater. CONSTITUTION:A water supply header part 2, a heat exchange port 3 and a steam header part 4 are successively provided in a container 1 and a plurality of water pipes 6 piercing the heat exchange part 3 to allow the water supply header part 2 and the steam header part 4 to communicate with each other are provided and a steam generating part 8a is formed between the end parts 6a on the side of the water supply header part 2 of the water pipes 6 and the water level WL at the time of operation of the water supplied into the water pipes 6 and a steam superheating part 8b is formed between the water level WL and the end parts 6b on the side of the steam header part 4 of the water pipes 6. A conc. water discharge chamber 10 is provided to be adjacent to the water supply header part 2 and conc. water discharge pipes 11 each having an outer diameter smaller than the inner diameter of each of the water pipes 6 and piercing the water supply header part 2 to allow the concn. water discharge chamber 10 and the water pipes 6 to communicate with each other are provided and the end parts on the side of the water pipes 6 of the conc. water discharge pipes 11 are positioned between the end parts 6a and the water level WL within the water pipes 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clean superheated steam generator for producing clean superheated steam used for cleaning semiconductors, precision parts and the like.

[0002]

2. Description of the Related Art It is well known that CFC is used as a cleaning agent for semiconductors and precision parts. However, in recent years, the destruction of the ozone layer by CFCs has become a major environmental problem, and the use of superheated steam of pure water (hereinafter referred to as clean superheated steam) as a substitute for CFCs is being considered. As a device for producing clean superheated steam, for example, a device as shown in FIG. 3 has been proposed. The apparatus is connected to the steam generator 34 for heating the water supplied through the water supply line 33 to form steam, and superheats the steam supplied from the steam generator 34. It comprises a steam superheater 35 for converting to superheated steam, a control unit 36 for controlling the entire apparatus, and a separator 37 provided in the steam generator 34 for removing droplets from the steam.

As shown in FIG. 4, the steam generator 34 has a water supply header section 39, a heat exchange section 40, and a steam header section 41 in order inside a container 38, and as shown in FIG. 3, the water supply header section 39. A water supply line 33 is connected to, and water is supplied through the water supply line 33. The supplied water is substantially pure water obtained by subjecting raw water to microfiltration, deionization, deaeration, and the like. As shown in FIG. 4, the heat exchange part 40 penetrates the heat exchange part 40 and the water supply header part 39 and the steam header part 4
1 has a plurality of water pipes 42 communicating with each other. As shown in FIG. 3, a steam line 43 is connected to the heat exchange section 40, and heating steam is supplied through the steam line 43. Water pipe 42
The space between the outer circumference of the water container and the inner circumference of the container 38 functions as a steam jacket and heats the water in the water pipe 42. Further, the steam header portion 41 has a separator 37 at the center thereof, which removes droplets from the steam by centrifugal force due to the swirling flow, and a drain line 44 is connected to the steam header portion 41 and removed by the separator 37. The formed droplets are discharged through the drain line 44.

As shown in FIG. 5, the steam superheater 35 has a steam header section 46, a heat exchanging section 47, and a superheated steam header section 48 in a container 45 in order, and as shown in FIG. 46 is connected to the steam header portion 41 of the steam generator 34 by a steam line 49. As shown in FIG.
The heat exchanging part 47 has a plurality of conduction pipes 50 penetrating the heat exchanging part 47 and communicating the steam header part 46 and the superheated steam header part 48. As shown in FIG. Is connected to a steam line 51, and heating steam is supplied through the steam line 51. The space between the outer circumference of the conduction pipe 50 and the inner circumference of the container 45 functions as a steam jacket, and superheats the steam in the conduction pipe 50. Further, an overheated steam supply line 52 is connected to the overheated steam header section 48, and the overheated steam is supplied to a load such as a cleaning unit via the overheated steam supply line 52.

The control unit 36 controls the pressure of the heating steam supplied to the steam generator 34 and the steam superheater 35, the steam pressure in the steam header portion 41 of the steam generator 34, the steam before and after the steam superheater 35. By detecting the temperature and the water level of the water pipe 42 of the heat exchange section 40 of the steam generator 34, the openings of the control valves V1 to V3 of the steam lines 43, 49, and 51 were adjusted and connected to the steam superheater 35. Superheated steam is supplied according to the load. Further, in FIG. 3, reference numeral 53 is a water level control cylinder attached to the steam generator 34. The water level control cylinder 53 detects the water level of the water pipe 42 of the heat exchange section 40, and based on the detected value. The amount of water supplied to the steam generator 34 is controlled.

When the clean superheated steam producing apparatus having the above-mentioned structure is started, water is supplied from the water supply line 33 to the water supply header section 39 of the steam generator 34 and is filled up to the set water level of the water pipe 42. Next, the heating steam is supplied from the steam lines 43 and 51 to the steam generator 34 and the heat exchange sections 40 and 47 of the steam superheater 35. The water in the water pipe 42 is heated,
Steam bubbles are generated from the inner surface of the lower portion of the water pipe 42, push up the water in the water pipe 42, and reach the vicinity of the upper end of the water pipe 42. Then, the water and the steam are separated near the upper end of the water pipe 42, the steam flows into the steam header portion 41, the droplets contained in the steam are removed by the separator 37, and a saturated dry steam is obtained. Become. Then, the steam is supplied to the steam header section 46 of the steam superheater 35 through the steam line 49, flows into the conduction pipe 50 of the heat exchange section 47, and is further superheated to a temperature equal to or higher than the saturation temperature to become superheated steam. It flows into the steam header portion 48. Then, the superheated steam is supplied to the load such as the cleaning unit via the superheated steam supply line 52.

By the way, in the above-mentioned clean superheated steam manufacturing apparatus, since the steam generator 34 and the steam superheater 35 are provided independently, the entire apparatus becomes large and the number of parts constituting the apparatus is large. ..

[0008]

Therefore, an object of the present invention is to integrate a steam generator and a steam superheater in a clean superheated steam generator.

[0009]

The clean superheated steam generator of the present invention is provided with a water supply header part 2, a heat exchange part 3 and a steam header part 4 in this order in a container 1, and penetrates the heat exchange part 3 to form a water supply header part 2. A plurality of water pipes 6 communicating with the steam header portion 4 are provided, water is supplied to the water supply header portion 2, heating steam is supplied to the heat exchange portion 3, and water is supplied into the water pipe 6 via the water supply header portion 2. In a steam generator that heats water to generate steam, the water level WL of the water supplied into the water pipe 6 during operation is located inside the water pipe 6, and the end of the water pipe 6 on the side of the water supply header 2 The steam generating portion 8a is formed between the portion 6a and the water level WL, and the steam superheating portion 8b is formed between the water level WL and the end portion 6b of the water pipe 6 on the steam header portion 4 side. The steam generated in the above is superheated in the steam superheating section 8b and concentrated adjacent to the water supply header section 2. The discharge chamber 10 is provided, have an outside diameter smaller than the inside diameter of the water pipe 6, the water supply header 2 through the concentrated water discharge chamber 10 and the concentrated water discharge pipe 1 that communicates the water pipe 6
1 is provided, and the end of the concentrated water discharge pipe 11 on the water pipe 6 side is connected to the water pipe 6
Located in the interior between the end 6a and the water level WL, and the water in the water pipe 6 is passed through the concentrated water discharge pipe 11 to the concentrated water discharge chamber 10
It is characterized by being discharged inside.

[0010]

When the water in the water pipe 6 is heated, steam bubbles are generated from the inner surface of the water pipe 6, and the steam bubbles cause the water in the water pipe 6 to be almost at the water level W.
It is pushed up to the position of L, water and steam are separated in the vicinity of the water level WL, and the steam is further heated to the saturation temperature or higher in the steam superheating section 8b and becomes superheated steam. The water separated from the steam flows into the opening at the upper end of the concentrated water discharge pipe 11 and flows into the concentrated water discharge chamber 1
It is discharged into 0. Therefore, new water is replenished in the water pipe 6 from the water supply header portion 2 and the water in the water pipe 6 is diluted, so that the water in the water pipe 6 can be prevented from being concentrated.

[0011]

EXAMPLES Examples of the present invention will be described below. FIG. 1 is a vertical cross-sectional view of the clean superheated steam generator of the present invention, in which a water supply header portion 2, a heat exchange portion 3, and a superheated steam header portion 4 are sequentially provided in a container 1. A water supply line 5 is connected to the water supply header portion 2, and water that is substantially pure water is supplied through the water supply line 5. The heat exchange section 3 is a heat exchange section 3
Has a plurality of water pipes 6 penetrating therethrough to connect the water supply header portion 2 and the superheated steam header portion 4 to each other. A steam line 7 is connected to the heat exchange section 3, and heating steam is supplied to the heat exchange section 3 via the steam line 7. The space between the outer circumference of the water pipe 6 in the heat exchange section 3 and the inner circumference of the container 1 functions as a steam jacket to heat the water in the water pipe 6.
In addition, in this device, the water level WL of the water supplied into the water pipe 6 during operation is located near the midpoint of the water pipe 6, and the water level WL between the end 6a of the water pipe 6 on the side of the water supply header 2 and the water level WL. It functions as a steam generating portion 8a, and a portion between the water level WL and the end portion 6b of the water pipe 6 on the side of the superheated steam header portion 4 functions as a steam superheating portion 8b. An overheated steam supply line 9 is connected to the overheated steam header portion 4, and the overheated steam supply line 9 is connected to a load such as a cleaning unit. Then, a concentrated water discharge chamber 10 is provided adjacent to the water supply header part 2, and a concentrated water discharge pipe 11 having an outer diameter smaller than the inner diameter of the water pipe 6 is provided so as to penetrate the water supply header part 2, and one end thereof is a water pipe. 6 is located in the concentrated water discharge chamber 10, and the other end projects into the concentrated water discharge chamber 10. A drain line 12 for discharging water is connected to the concentrated water discharge chamber 10.
A water level control cylinder 13 is attached to the container 1, and the water level control cylinder 13 detects the water level in the water pipe 6 and is supplied to the water supply header section 2 from the water supply line 5 based on the detected value. It is designed to control the amount of water.

When the clean superheated steam generator having the above structure is driven, water is supplied from the water supply line 5 to the water supply header section 2.
And the water pipe 6 is filled up to a predetermined water level. Then, the heating steam is supplied from the steam line 7 to the heat exchange unit 3, the water in the water pipe 6 is heated, and when the water temperature reaches the saturation temperature, steam bubbles start to be generated from the inner surface of the water pipe 6, and this flows upward. As they move, they coalesce and form bubbles, pushing up the water, and the water almost reaches the water level WL. Steam and water are separated in the vicinity of the water level WL, and the steam is further heated in the steam superheating section 8b to a temperature equal to or higher than the saturation temperature to become superheated steam, which then flows into the superheated steam header section 4. Then, the superheated steam is supplied to the load such as the cleaning unit via the superheated steam supply line 9.

On the other hand, the water separated from the steam near the water level WL flows into the opening at the upper end of the concentrated water discharge pipe 11 and is discharged into the concentrated water discharge chamber 10 through the concentrated water discharge pipe 11. When the water level in the water pipe 6 is lowered, it is detected by the water level control cylinder 13, water is supplied from the water supply line 5 to the water supply header portion 2, the water pipe 6 is replenished with water, and the water level in the water pipe 6 is constant. Kept in. Therefore, the water in the water pipe 6 is diluted,
It is possible to prevent the water in the water pipe 6 from being concentrated.
The concentrated water in the concentrated water discharge chamber 10 is drain line 1
It is discharged to the outside via 2.

In this clean superheated steam generator, the steam generator and the steam superheater, which are independently provided in the conventional device, are integrated by generating and superheating steam in the same water pipe. The size is greatly reduced as compared with the conventional device, and the number of parts constituting the device is significantly reduced. Also, by generating steam and heating in the same water pipe, without losing the heat of steam before overheating,
Superheated steam can be efficiently produced.

The position of the water level WL is not limited to the position of this embodiment, and can be set at any position so that the steam generating part and the steam superheating part are formed in the water pipe.

As another method for downsizing the device,
It is also conceivable to combine the steam generator and the steam superheater into one, as shown in FIG. In this device, a steam generator 14 and a steam superheater 15 are detachably connected.
The steam generator 14 has substantially the same structure as the steam generator 34 shown in FIG. 4, and a water supply header portion 17, a heat exchange portion 18, and a steam header portion 19 are sequentially provided in the container 16, and the heat exchange portion 1 is provided.
8 has a plurality of water pipes 20 penetrating 8 to connect the water supply header section 17 and the steam header section 19 to each other, the water supply line 21 is connected to the water supply header section 17, and the steam for supplying heating steam to the heat exchange section 18 The line 22 is connected to the water pipe 2 in the container 16.
A water level control cylinder 23 that detects the water level in 0 and controls the amount of water supplied to the water supply header section 17 is connected, and a separator 24 for removing droplets from the steam is provided in the steam header section 19. A drain line 25 for discharging the liquid droplets removed from the steam is connected to the steam header section 19. The steam superheater 15 has a structure similar to that of the steam superheater 35 shown in FIG.
The heat exchange section 28 and the superheated steam header section 29 are provided, and the heat exchange section 28 has a conduction pipe 30 which penetrates the heat exchange section 28 and communicates the steam header section 27 with the superheated steam header section 29. A steam line 31 for supplying steam is connected, and a superheated steam line 32 for supplying superheated steam to a cleaning unit or the like is connected to the superheated steam header portion 29.

When the above device is driven, the water supply line 21
From the steam generator 14 to the water supply header portion 17 of the water, the water pipe 20 is filled with water to a predetermined water level, the steam line 22 to the heat exchange portion 18 to supply heating steam, the water pipe 2
The water in 0 is heated to generate steam bubbles, the water is pushed up to near the upper end of the water pipe 20, and the water and steam are separated at the upper end of the water pipe 20. The steam flows into the steam header section 19, the droplets are removed by the separator 24, and the steam flows into the steam header section 27 of the steam superheater 15. The steam flows into the conduction pipe 30 of the heat exchange unit 28, the heating steam is supplied from the steam line 31 to the heat exchange unit 28, the vapor in the conduction pipe 30 is superheated to the saturation temperature or higher, and becomes superheated steam. It flows into the superheated steam header section 29. The superheated steam is supplied to the cleaning unit or the like via the superheated steam line 32.

In this apparatus, the steam generator 14 and the steam superheater 15 can be used separately. In that case, the steam header portion 19 of the steam generator 14 and the steam header portion 27 of the steam superheater 15 are connected by a tubular steam line.

[0019]

As described above, according to the clean superheated steam generator of the present invention, since the steam generator and the steam superheater are integrated, the size can be greatly reduced as compared with the conventional device. In addition, the number of parts constituting the device can be significantly reduced. It is also possible to prevent heat loss of steam and improve the efficiency of producing superheated steam. Therefore, the intended purpose can be achieved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a clean superheated steam generator of the present invention.

FIG. 2 is a vertical cross-sectional view of a clean superheated steam generator in which a steam generator and a steam superheater are detachably connected.

FIG. 3 is a schematic view of a conventional clean superheated steam generator.

FIG. 4 is a side view in which a part of a conventional steam generator is cut away.

FIG. 5 is a side view in which a part of a conventional steam superheater is cut away.

[Explanation of symbols]

 1 Container 2 Water Supply Header Section 3 Heat Exchange Section 4 Steam Header Section 6 Water Pipe 6a Water Pipe 6 Water Supply Header Section 2 Side End 6b Water Tube 6 Steam Header Section 4 Side End 8a Steam Generation Section 8b Steam Overheating Section 10 Concentration Water discharge chamber 11 Concentrated water discharge pipe WL Water level

Claims (1)

[Claims] 1. A water supply header portion 2, a heat exchange portion 3, and a steam header portion 4 are sequentially provided in a container 1, and the water supply header portion 2 and the steam header portion 4 are communicated with each other through the heat exchange portion 3. A plurality of water pipes 6 are provided, water is supplied to the water supply header portion 2, heating steam is supplied to the heat exchange portion 3, and water supplied into the water pipe 6 via the water supply header portion 2 is supplied. In the steam generator that is heated to generate steam, the water level WL of the water supplied into the water pipe 6 during operation is located inside the water pipe 6, and the water pipe 6 on the side of the water supply header portion 2 of the water pipe 6 is located. A steam generating portion 8a is formed between the end portion 6a and the water level WL, and a steam superheating portion 8b is formed between the water level WL and the end portion 6b of the water pipe 6 on the steam header portion 4 side. , Superheat the steam generated in the steam generating section 8a in the steam superheating section 8b. Then, a concentrated water discharge chamber 10 is provided adjacent to the water supply header part 2, has an outer diameter smaller than the inner diameter of the water pipe 6, and penetrates the water supply header part 2 to form the concentrated water discharge chamber 10. A concentrated water discharge pipe 11 that communicates with the water pipe 6 is provided, and an end portion of the concentrated water discharge pipe 11 on the side of the water pipe 6 is connected to the end portion 6a and the water level W in the water pipe 6.
A clean superheated steam generator characterized in that the water in the water pipe (6) is discharged into the concentrated water discharge chamber (10) through the concentrated water discharge pipe (11).