JPS60126505A - Decompression type steam generator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (a) Industrial Applications i This invention is a depressurizer that removes noncondensable gas generated inside a closed container that generates steam while maintaining a pressure below atmospheric pressure. Regarding steam generators.

(b) A conventional technology vacuum steam generator is a heat exchanger tube in which water or other heat medium liquid is sealed in a closed container, heated by a heat source such as gas or oil, and indirectly heated by heat medium vapor inside the container. A hot water supply system or a heating device is connected to this, and the hot water is used for space heating, hot water supply, etc. In order to operate while maintaining the internal pressure of the closed container below atmospheric pressure, Although it has advantages such as safe handling and excellent thermal conductivity, it generates non-condensable gas (mainly hydrogen gas) due to electrochemical action, which inhibits heat conduction to the heat transfer surface. There are drawbacks such as.

A vacuum pump is generally used to exhaust noncondensable gas generated within a closed container. In the case of using a vacuum bonder, handling is inconvenient because the vacuum pump is operated to discharge the non-condensable gas when a considerable amount of it has accumulated.

In order to solve this inconvenience, a method using a polymer membrane is disclosed in Japanese Patent Publication No. 57-27366. This can be summarized based on the drawings in the same publication (see Figure 1). A gas storage chamber (f) having a non-condensable gas permeation outlet, which has a communication hole (d) communicating with the atmosphere and is covered with a polymer membrane (e).
) is attached to the polymer membrane (e), and the hydrogen gas generated in the closed container fbl permeates and flows out into the atmosphere by utilizing the gas permeability due to the partial pressure of the polymer membrane (e). ) has poor heat resistance, so the polymer membrane (e) must be cooled to maintain the polymer membrane temperature at the set temperature, and the gas permeation selectivity of the polymer membrane (e) is Because of its weakness, there was a problem that nitrogen gas, oxygen gas, etc. in the atmosphere could permeate into the inside of the sealed container (bl) depending on the partial pressure difference between the inside and outside of the sealed container (b).Also, the polymer membrane (e) cannot be regenerated. ” and as appropriate.
Had to replace it with a new one.

(c) Purpose of the Invention This invention was made in view of the above facts, and while eliminating the drawbacks of using a vacuum pump or polymer membrane, it also solves the problem of non-condensation occurring inside a closed container The purpose is to remove hydrogen gas and maintain highly efficient heat transfer performance.

B) Structure of the Invention In order to achieve the above object, the reduced pressure steam generator of the present invention is maintained at a pressure below atmospheric pressure, and a non-condensable gas is placed at the top of the steam chamber of a closed container in which a heat transfer liquid is sealed. A reservoir is provided,
This non-condensable gas reservoir is equipped with a palladium tube that partially communicates with the atmosphere, and a heater is installed near this palladium tube.
), the palladium tube is heated by a heater, and hydrogen gas is continuously released from the non-condensable gas reservoir to the atmosphere by utilizing the property of selectively permeating only hydrogen gas due to its partial pressure difference.

(e) Examples Hereinafter, embodiments of the present invention shown in the drawings will be described.

In FIG. 2, 'C (1) is a closed container in which water or other heat transfer liquid (2) is sealed. (3)
is a heating device that heats the heat transfer liquid (2) from below the closed container (1), (4) is the steam chamber of the closed container (1), and (5) and (6) are each installed in the steam chamber (4). (7) is an air vent pipe for evacuation of the inside of the closed container (11 and filling of the heat transfer liquid (2));
(8) is a non-condensable gas reservoir connected to the top of the steam chamber (4) via a conduit (9), α0) surrounds the outer periphery of the conduit (9), and is used for heating heat transfer/n(6) This is a cooling jacket that bypasses a portion of the liquid supplied to the tank.

As shown in Fig. 3, a palladium tube Ql) is installed through the non-condensable gas reservoir (8) with the inner wall of the tube open to the atmosphere, and a palladium tube Ql) is installed near the palladium tube 0]J. Heater (12
1 is arranged.

The above-mentioned reduced pressure steam generator uses a heating device (
When heated in step 3), reduced pressure steam αJ is generated. The reduced pressure steam α3) supplies latent heat of condensation to the liquid flowing through both heat transfer tubes (5) and (6), transfers the heat obtained from the heating device (3), and liquefies itself into the heat transfer liquid (2). return. In this way, heat exchange is performed by condensing heat transfer of steam, so the amount of heat exchange per heat transfer area is larger than in liquid-liquid heat exchange in a normal hot water boiler, and the thermal efficiency is high. In addition, the pressure in the steam chamber (4) is always kept below atmospheric pressure, making it highly safe.

When non-condensable gas (mostly hydrogen gas) is generated in the closed container (1) by electrochemical action, this non-condensable gas collects around the heat transfer tubes (5) and (6) during heat transfer. 9. Obstruct heat transfer and increase the pressure in the steam chamber (4).

Therefore, in this example, we focused on the fact that the non-condensable gas is mainly hydrogen gas, and transferred hydrogen gas with a small specific gravity to the steam chamber (
4) Store in the gas reservoir (8) at the top. The hydrogen gas accumulated in the gas reservoir (8) is heated to a high temperature (300 to 350℃) by the heater 02).
It passes through a palladium tube (formerly) heated to 100°F (°C) and is continuously released into the atmosphere from the inner wall of the tube.

For this reason, the inside of the closed container (1) is maintained in a state where there is almost no hydrogen gas, and heat transfer is hindered (or trapped).
Pressure rise is suppressed.

Palladium has a strong property of selectively permeating hydrogen gas (
Unlike polymer membranes, it is not permeable to other gases, and of course has sufficient heat resistance. Further, the amount of permeation of hydrogen gas is expressed by the following equation.

Furthermore, in this embodiment, a cooling jacket (0 cut) is provided around the conduit (9), and this jacket aor is provided with a heating heat exchanger tube (
6) is bypassed to supply the flowing liquid, hydrogen gas can be collected in the non-condensable gas reservoir (8) during heat transfer and efficiently released into the atmosphere from the palladium tube (old). .

In addition, the palladium tube 01) has a length of 50mm, an inner diameter of 3mm,
The pole with a tube thickness of about 0.5 mm (a small one is fine (and the heater 02 that heats this) may have a small capacity of several tens of W.

(f) Effects of the invention: This invention is constructed as described above, and hydrogen gas generated inside a closed container is continuously transmitted through a palladium tube heated with a heater and released into the atmosphere. By eliminating the obstruction of heat conduction and pressure rise caused by non-condensable gases, it is possible to maintain high heat transfer performance, prevent increases in running costs, and improve safety.Moreover, when using a vacuum pump There is no inconvenience in handling, and there are no problems with heat resistance or replacement due to deterioration that occur when using polymer membranes. Furthermore, only hydrogen gas can be efficiently discharged, while other gases can be removed from the airtight container. It is easy to use and highly reliable, as it can prevent water from flowing into the air.

[Brief explanation of drawings]

Fig. 1 is a schematic structural diagram showing an example of a conventional reduced pressure steam generator, Fig. 2 is a schematic structural diagram of an embodiment of the present invention, and Fig. 3 is an enlarged perspective view of the main part of Fig. 2. . (1)...Airtight container, (2)...Heating medium liquid, (4
)...Steam chamber, (8)...Noncondensable gas reservoir, ■
...Palladium tube, (121...Heater.

Claims (1)

[Claims] (1) A non-condensable gas reservoir is provided at the top of the steam chamber of a closed container that is maintained at a pressure below atmospheric pressure and has a heat transfer liquid sealed inside, and a portion of this non-condensable gas reservoir is exposed to the atmosphere. A reduced pressure steam generator characterized in that it is equipped with a palladium tube that communicates with the palladium tube, and a heater is installed near the palladium tube.