JP2007046818A - Steam generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for generating steam of good quality harmless to human bodies and usable for food processing and a steam sauna bath utilizing steam obtained in a once-through steam boiler. <P>SOLUTION: This steam generator 1 comprises a heat exchanger 9 in a pressure vessel 2 having a water supply port 6 leading in clean water, and a good quality steam outlet pipe 3 for taking out generated clean steam, wherein the heat exchanger 9 carries out heat exchange of heat of steam led in from an external steam boiler, with water in the pressure vessel to evaporate the water in the pressure vessel. Condensate produced from steam with its heat taken away in the heat exchanger 9 is taken out and supplied into the pressure vessel 2 after steam separation by a steam trap 10. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a steam generator, and in particular, high-quality steam that is sufficiently safe even if a person obtains the steam obtained by a once-through steam boiler that has been widely used in the past or is used for food processing. The present invention relates to a relatively inexpensive and efficient steam generating device for converting into water.

Recently, among various steam boilers, for example, the once-through steam boiler as shown in Patent Document 1 below is simple in structure and has a small amount of water, so it can easily cope with load fluctuations, and the apparatus can be further downsized. It is most often used for reasons such as low manufacturing costs.
That is, a large number of once-through steam boilers are used in comparison with other models, ranging from large steam boilers for power generation to very small simple steam boilers.

However, the steam generated from this once-through steam boiler contains substances that are harmful to the human body, and there is a problem that it is harmful to the human body if it is inhaled by humans or ingested with this steamed food. It was.
That is, in the once-through boiler, steam evaporates from a very thin water pipe, so if a large amount of steam is suddenly generated from a very narrow evaporation surface, a phenomenon such as priming or homing occurs, and part of the can water is discharged together with the steam. However, this can water contains chemicals called “cleaning agents” for keeping the boiler interior clean, and many of these chemicals are harmful to the human body.
Therefore, it is necessary to avoid as much as possible that a human inhales or ingests with the food the vapor | steam mixed with such a harmful substance which has a bad influence on a human body even if it is a trace amount.
Therefore, steam generated from a once-through steam boiler is rarely used as steam for sauna baths or steam for food processing that is sucked into the human body. Most of the steam obtained by the once-through steam boiler is often used as a heat source or a pressure source of various apparatuses. This is because the once-through steam boiler has a number of excellent features such as small size, high thermal efficiency, lower cost, and superior safety.

On the other hand, a steam boiler that has a large and wide evaporation area like a traditional three-pass boiler, a sufficiently low evaporation amount per unit evaporation surface, and a large amount of water is widely used. Are known.
However, these steam boilers having a sufficiently wide evaporation surface have a problem that they are larger and require a larger installation area, and the installation cost of the product is high.
Therefore, in order to generate high-quality steam that is harmless to the human body, when installing other types of steam boilers with a larger evaporation area without using a once-through steam boiler, initial costs such as equipment costs are high. In addition, the running cost may increase from the viewpoint of thermal efficiency.

Further, in Korea and Japan, a steam generator for obtaining steam for a steam sauna by indirectly using steam from a boiler has been conventionally used.
This system uses steam from a steam boiler, such as a once-through boiler, as a heat source, indirectly heats water, humidifies and heats the steam sauna room with high-quality steam that is secondarily generated from a wide evaporation surface. Herb steam saunas have been proposed, and some of them have been put into practical use.
However, this steam sauna steam generator has two problems.
One of the problems is that a ball tap is used for replenishing water heated by boiler steam, so that dust adheres to or damages the valve portion of the ball tap and often causes water leakage.
Another problem is that if tap water or the like is used as it is without using a water softening device, a large amount of impurities adhere to the heat exchanger and often hinder heat exchange. This is because when the water to be supplied is hard water and impurities such as calcium are dissolved, when the water is concentrated, these dissolved impurities are precipitated in the apparatus.

JP 2004-251487 A

An object of the present invention is to solve the various problems described above.
The present invention is that only a small part of the steam generated from the once-through steam boiler is used in a field that may be sucked into the human body or ingested with food. Attention is focused on developing a steam generator that uses a part of the steam generated from a once-through steam boiler as a heat source, can generate high-quality steam that is simple, inexpensive, and does not adversely affect the human body. is there.
That is, the present invention supplies most of the steam obtained by using a once-through steam boiler to various devices as it is, and converts the remaining part of the steam into high-quality steam for food and drinking. High-quality steam generator with simple structure and lower cost, which uses steam from a once-through steam boiler as a heat source to generate high-quality steam from a wider evaporation surface to supply to a small part of equipment that may be generated Is to develop.
If such a device is provided, the steam of the once-through steam boiler is directly sent to a device that can be directly operated with the steam using a small-sized, inexpensive and highly efficient once-through steam boiler. If high-quality steam is supplied from the once-through steam boiler via the apparatus of the present invention only to equipment that requires high-quality steam that is harmless to the human body, it is low in both initial cost and running cost. Use facilities can be obtained.

In order to solve the above problems, a steam generator according to the present invention is:
The heat of the steam introduced from an external steam boiler is exchanged with the water in the pressure vessel in a pressure vessel having a water supply port for introducing clean water and a high-quality steam outlet pipe for taking out the generated clean steam. In the steam generator comprising a heat exchanger for evaporating water in the pressure vessel by
The condensed water generated by the steam deprived of heat in the heat exchanger is taken out, and the condensed water is separated into steam and water by a steam trap, and then the condensed water is supplied into the pressure vessel. Is.

That is, the present invention provides a heat exchanger that uses steam from a once-through steam boiler as a heat source in a pressure vessel containing purified water (tap water), indirectly heats the purified water with the heat exchanger, By evaporating from a wide evaporation surface with little homing, it is configured to generate high-quality steam that does not contain canned water, can be safely sucked in harmlessly to humans, and is safe to be used for food. The steam from the boiler is deprived of heat by the heat exchanger and condensed to return to the hot water. This hot water is supplied into the pressure vessel and is taken out as a high-quality steam that evaporates again from the wide evaporation surface. Is. Hazardous substances to the human body contained in the condensed water remain in the can water, and the vapor that has evaporated again is high-quality vapor that is harmless to the human body.
Specifically, steam containing substances harmful to the human body is cooled by a heat exchanger, condensed into hot water, steam and condensed water are separated using a steam trap, and the separated condensed water is heat exchanged. The water is supplied to the water side of the heated portion of the vessel, re-evaporated as a high-quality steam from a wide evaporation surface, and supplied to the downstream steam using device.

  In the above configuration of the present invention, at least one of a water level detection device that automatically detects the water level in the pressure vessel, and a water supply electric valve and a drainage electric valve provided in the pressure vessel based on an output signal of the water level detection device. And a control device for automatically adjusting the water level in the pressure vessel by controlling the opening / closing operation of the pressure vessel.

  Furthermore, a herb container pot through which clean steam taken out from the high-quality steam outlet pipe of the pressure vessel passes is provided, and the aromatic steam obtained through the herb container pot is discharged into the sauna bathroom. It is also recommended.

Of the various devices that use steam from the once-through steam boiler, the device of the present invention can be provided only to devices that are likely to be sucked and eat or drink by humans, thereby supplying high-quality steam that is harmless to humans. That is, the steam generated from the wide evaporation surface of the apparatus of the present invention is a high-quality steam that is harmless to the human body.
Most of the water supplied to the apparatus of the present invention is a kind of distilled water in which the steam of the boiler is condensed, and is very good quality water that is almost close to pure water.
Of course, it contains an extremely small amount of a component harmful to the human body called a canning agent, but there is almost no dissolved matter such as calcium, and there is no possibility of concentrating to precipitate impurities.
Although the generated steam is harmful to the human body, most of the steam of the low-cost and high-efficiency once-through boiler is supplied to ordinary equipment that requires steam, and only the remaining steam of the once-through boiler is small. If it is converted into high-quality steam using the simple and high-quality steam generator of the present invention and then supplied only to a device that can be sucked and eat and drink, the initial cost is harmless to the human body. It is possible to construct a steam facility with low running costs.

Most of the water supplied into the pressure vessel of the steam generator of the present invention is water in which steam from the boiler is condensed. It is very close to pure water and is the best water for generating good-quality steam. It is.
As described above, for steam saunas, conventionally, some devices have been used to heat tap water with steam from a boiler and generate high-quality steam. There is a problem that the device may become inoperable due to adhesion to the surface, and the ball tap is broken because the ball tap is used to supply tap water.
On the other hand, the apparatus of the present invention has no fear of precipitation of impurities such as calcium, and there is no failure compared to the case of using a conventional ball tap, and maintenance management is easier than that of the conventional apparatus.

As a field where high-quality steam that is harmless to the human body is required and the apparatus of the present invention is effective, first, there is a field of processing and manufacturing various foods. For example, the field of food production including the step of steaming cereals such as rice, wheat and soybeans, that is, the field of production of confectionery and rice cake, the field of beer and liquor, the field of miso and soy sauce can be mentioned. Moreover, the field | area containing the process of steaming meat and fish meat, ie, the manufacture field | areas, such as a sausage and a salmon, is mentioned. In food processing, there are many fields other than these that require high-quality steam, and the steam generator of the present invention can be used very suitably in many of these fields.
Furthermore, as described above, the steam generator of the present invention can be suitably used in a steam sauna bath apparatus in which a person directly sucks steam as described above, in addition to the food manufacturing field. The steam of the steam sauna bath device that is originally recommended for health promotion should not be harmful to the human body. The most desirable steam for bathing.

The best mode for carrying out the present invention will be specifically described below with reference to the drawings.
FIG. 1 is a flow sheet showing a first embodiment of a steam generator according to the present invention,
FIG. 2 is a flow sheet showing a second embodiment of the steam generator according to the present invention having a water level automatic adjustment function,
FIG. 3 is a flow sheet showing a third embodiment of the steam generator according to the present invention for a steam sauna room.

Hereinafter, a first embodiment of a steam generator according to the present invention will be described with reference to FIG.
FIG. 1 is a flow sheet showing an embodiment of the first embodiment of the present invention. In the upper part of the pressure vessel 2 of the high-quality steam generator 1, the high-quality steam outlet pipe 3, the water level gauge 4, and the steam from the boiler are condensed. A condensed water supply pipe 5 for supplying the water into the pressure vessel and a tap water supply port 6 are provided. At the lower part of the high-quality steam generator 1, a blow drain pipe 7 is provided, the lower end of the pressure vessel 2 is closed by a flange 8, and the flange 8 has a heat exchange built coaxially with the pressure vessel 2. A flange 9-1 of the container 9 is fixed detachably.
A boiler steam inlet pipe 9-2 and a condensed water outlet pipe 9-3 are provided below the flange 9-1 of the heat exchanger 9, and a steam trap 10 and an air vent valve 11 are provided in the condensed water outlet pipe 9-3. Are provided in parallel.

First, the water supply valve 6-1 connected to the water supply port 6 is manually opened, tap water is supplied into the pressure vessel 2 of the steam generator 1, and the water level rises to about 4-1 of the water level gauge 4. The water supply valve 6-1 is closed, and the steam from the once-through boiler is introduced into the heat exchanger 9 provided in the steam generator 1 through the boiler steam inlet pipe 9-2.
The boiler steam that has flowed into the heat exchanger 9 rises while indirectly heating the water between the pressure vessel 2 and the heat exchanger 9 as indicated by the arrow in the heat exchanger 9, the temperature drops, and the steam The condensed water condensed into water descends in the heat exchanger 9 and flows into the steam trap 10 from the condensed water outlet pipe 9-3.
Steam and water are separated by the steam trap 10, and only the condensed water rises and is supplied into the pressure vessel 2 through the condensed water supply pipe 5 as shown by the arrow.
The air vent valve 11 is a manual air vent valve provided for venting the steam piping from the boiler and the air inside the heat exchanger at the time of starting.
Further, a blow valve 12 is provided to drain water from the pressure vessel 2 as necessary.

Here, the change of the water level of a present Example is demonstrated.
Since the boiler steam that flows in has higher pressure and the amount of heat per unit mass is higher than the steam that flows out from the high-quality steam outlet pipe 3, if there is no heat radiation from the piping or equipment, the amount of heat supplied from the boiler However, since the amount of heat per unit mass supplied downstream from the high-quality steam outlet pipe 3 is small, the amount of water (mass) supplied to the pressure vessel 2 is less than the amount of water (mass) supplied downstream, and the water level decreases. .
When the total amount of heat of the steam supplied decreases due to heat dissipation or the like and becomes smaller than the total amount of heat of steam supplied downstream, the water level rises.
When the total heat quantity of steam from the boiler is the same as the sum of the heat quantity of steam supplied downstream and the heat quantity by heat radiation, the water does not increase or decrease and the water level does not change. That is, when the amount of condensed water of boiler steam is the same as the amount (mass) of steam supplied downstream, the water level does not change.

Although not shown in FIG. 1, the outer peripheral surface of the pressure vessel 2 of the high-quality steam generator 1, the lower protrusion of the heat exchanger 9, the boiler steam inlet pipe 9-2, the condensed water outlet pipe 9-3, etc. Naturally, the main parts other than the water level gauge 4 are kept warm.
Assuming that there is no heat dissipation of the device, the amount of water that decreases is often around 2% of the mass of the boiler steam that flows in.
If the heat radiation amount of the present invention apparatus and the accompanying steam pipe is larger than about 2%, the water level shown in the water level gauge 4 rises from the initial water level 4-1.
If the apparatus and the related steam pipes are kept warm appropriately and the heat radiation amount is suppressed to about 2% of the heat amount of the incoming steam, the masses of the incoming condensed water and the boiler steam are almost balanced, and the water level 4-1 hardly changes.

When the apparatus of the first embodiment is used continuously for a long time, water rises too much and hot water spouts out from the high quality steam outlet pipe 3, or the water level drops too low to lower than the heat exchanger 9, Reducing the efficiency of the exchange.
However, in the case of a high-quality steam using device that operates intermittently in a relatively short time, for example, an intermittent (batch type) steamer that steams rice etc., the water level change during one operation will be within the visible range of the water level gauge 4 What is necessary is just to determine the water amount of the visible range of a total of four.
In this case, the next time the steamer is operated, the blow valve 12 is manually opened and blown to lower the water level, or the water supply valve 6-1 is manually opened to supply water and the water level is raised to an appropriate height. Let
The high-quality steam generated from this first embodiment has a much larger evaporation area per unit evaporation than the area of the evaporation surface of the once-through steam boiler, it evaporates slowly, does not cause priming and homing, and contains canned water There is no good quality saturated steam.

Next, a second embodiment of the present invention will be described.
FIG. 2 is a flow sheet showing an aspect of the second embodiment, which is an embodiment in which a water level control device is provided in the first embodiment.
Unlike the first embodiment, the second embodiment is a variety of high-quality steam utilization devices that operate for a long time and that wants high-quality steam to be eaten, sucked, and sucked by humans, and the water level may change variously. The aspect of the apparatus used in a case is shown.
A water level detection device 13 is provided on the left side facing the water level gauge 4 of the first embodiment, a water supply electric valve 14 is provided on the downstream side of the water supply valve 6-1, and a blow electric valve 15 is provided on the upstream side of the blow valve 12.
In the water level detection device 13, four electrode rods 13-1, 13-2, 13-3, 13-4 for detecting the water level are provided.
The water level detection device 13 itself using this electrode rod is a known device widely used as a water level detection device for a steam boiler.

When the water level drops to the lower end 13-3L of the electrode rod 13-3, there is no water between the ground electrode rod 13-4 and the electrode rod 13-3, so no current flows, and the water level is reduced to the electrode rod 13 -3, that is, a signal that detects that the current between the electrode rod 13-3 and the ground electrode rod 13-4 has been cut off is sent to the control device 16, and the dotted line in FIG. As shown in the diagram, a voltage is automatically applied to the water supply electric valve 14, the water supply electric valve 14 is opened, and tap water is supplied into the pressure vessel 2 by the pressure of the water supply.
When the water level rises due to water supply and exceeds the lower end 13-2L of the electrode rod 13-2, a current flows between the electrode rod 13-4 for grounding and the electrode rod 13-2, and a signal notifying the controller 16 Then, the water supply electric valve 14 is closed and the water supply is stopped.
When the water level rises beyond the lower end 13-1L of the electrode rod 13-1, a current flows between the ground electrode rod 13-4 and the electrode rod 13-1, and a signal notifying this is sent to the control device 16, As shown by the dotted line, a voltage is applied to the blow motor-operated valve 15, the blow motor-operated valve 15 opens, and the water in the pressure vessel 2 is released to the outside. The water level is lowered by the blow, and the lower end 13-2L of the electrode rod 13-2 If it falls below, the electric current between the electrode rod 13-4 for earthing and the electrode rod 13-2 will be cut off, and a signal indicating this will be sent to the control device 16, the electric blow valve 15 will be closed and drainage will be stopped.

  In this way, if the water level is automatically controlled so as to keep the water level within a certain range, the apparatus of the second embodiment can be applied to various food processing apparatuses that are continuously operated, such as an automatic steamer that continuously manufactures potatoes, and a humidifier that is used for bread production. High-quality steam can be continuously supplied to a steam sauna or the like where a steam is directly sucked by a human.

Next, a third embodiment of the present invention will be described with reference to FIG.
FIG. 3 is a flow sheet showing an aspect of the high-quality steam generator 1 according to the present invention provided in the steam sauna room as a heat source for the steam sauna.
The feature of this device is that it is installed in a high humidity steam sauna room, so it causes poor insulation, so electrical devices and instruments are unsuitable, and since it is a device provided in the steam sauna room, heat dissipation from the device is It is used effectively for heating the sauna room, and it is two points that there is no need for heat insulation.

While starting, visually check the water level of the water level gauge 4 and open the water supply valve 6-1 to supply water from the water supply port 6. When the water level rises to an appropriate position, that is, about 4 to 1 of the water level gauge 4, the water supply is stopped. Then, boiler steam is supplied to the heat exchanger 9 from the boiler steam inlet pipe 9-2.
The boiler steam that has flowed in transmits heat to the water in the pressure vessel 2 through the heat exchanger 9, the steam condenses into water, is separated into steam and water by the steam trap 10, and only the condensed water is condensed water supply pipe. Water is fed into the pressure vessel 2 through 5.
At the time of start-up, since the temperature of the water in the pressure vessel 2 is low, steam does not flow to the downstream side (steam use device side), only water is supplied and the water level continues to rise, and when the water level rises to 4-2 As shown by the dotted line in FIG. 3, it overflows into the herb storage pot 17 and is discharged into the steam sauna room as shown by the dotted arrow.
When the temperature of the water in the pressure vessel 2 rises and high-quality steam is generated, the fragrance component of the herb in the herb storage pot 17 is added as shown by the solid line arrow in FIG. 3 and supplied to the steam sauna room as high-quality aromatic steam. The
When the temperature of the steam sauna room rises to an appropriate temperature (usually about 45 ° C.), the steam motor-operated valve (not shown) is closed, and the supply of boiler steam flowing in from the boiler steam inlet pipe 9-2 is stopped.
At this time, the supply of condensed water is stopped, but the water in the pressure vessel 2 is hot and hot, so self-evaporation is performed, and good quality aromatic steam continues to be supplied to the steam sauna room for a while.
At this time, since the self-evaporation is performed without supplying condensed water, the water level in the pressure vessel 2 is lowered.

As described above, the water level in the pressure vessel 2 of the steam generator 1 always fluctuates.
Here, the balance of water in the steam generator 1 when the present apparatus is operated will be considered.
First, considering the heat balance, the heat supplied to the high-quality steam generator 1 is obtained by multiplying the supply amount of the boiler steam by the heat amount of the boiler steam, and the heat emitted from the high-quality steam generator 1 is steam. The amount of good quality steam supplied to the sauna room multiplied by the amount of heat of good quality steam, the amount of heat radiated from the good quality steam generator 1, the water overflowing from the good quality steam generator 1, and the good quality steam generator It is the sum of the amount of heat with water increased within 1.
Since the third embodiment apparatus does not keep the heat, the amount of heat radiation is large, and the supplied boiler steam has a large amount of heat radiation except for particularly high pressure or high temperature superheated steam. The amount of high-quality steam to be supplied is smaller, the amount of water in the pressure vessel 2 of the steam generator 1 increases, and this increased water overflows.
On the other hand, the water level may temporarily decrease as described above, but if the total amount of condensed water supplied is larger than the amount of high-quality steam supplied downstream, the water level rises and often overflows. .

When operating a steam sauna, it is generally possible to operate by adjusting the water level artificially from time to time.
However, if it is difficult to adjust the water level artificially or when high-pressure steam or superheated steam is supplied, the amount of condensed water will be less than the amount of good quality steam and the water level will be extreme. May decrease.
In such a case, it is possible to prevent the water level from being extremely lowered by providing a ball tap or a small water tank with a built-in ball tap on the upstream side of the water supply port 6.
In that case, there remains a problem that the ball tap fails, but in the conventional device, all water for generating good quality steam is supplied from the ball tap, whereas in the device of the present invention, most of the water is supplied from the steam trap. Since it is sufficient to supply only a very small amount of water that is not covered by the condensed water from the ball tap, the probability that the ball tap will fail is low, and the problem that the ball tap fails can be greatly improved.

  Furthermore, in the conventional apparatus that generates high-quality steam by heating tap water with boiler steam, there is a problem that impurities such as calcium are deposited and the apparatus breaks down, but the condensed water supplied to the apparatus of the present invention Is the best water that can be said to be almost pure water, so there is no fear of such a failure and this problem can be solved.

  As described above, the present invention can achieve many excellent functions and effects that could not be achieved by conventional boilers and steam generators, and thus has great industrial applicability. .

It is a flow sheet which shows the 1st example of the steam generator concerning the present invention. It is a flow sheet which shows the 2nd example of the steam generator concerning the present invention which has a water level automatic adjustment function. It is a flow sheet which shows the 3rd Example of the steam generator which concerns on this invention for steam sauna rooms.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Steam generator 2 Pressure vessel 3 Good quality steam outlet pipe 4 Water level meter 4-1 Water level 5 Condensed water supply pipe 6 Water supply port 6-1 Water supply valve 7 Blow drain pipe 8 Pressure vessel flange 9 Heat exchanger 9-1 Heat exchange Flange 9-2 Boiler steam inlet pipe 9-3 Condensate outlet pipe 10 Steam trap 11 Air vent valve 12 Blow valve 13 Water level detection device 14 Water supply electric valve 15 Blow electric valve 16 Control device 17 Herb storage pot

Claims (3)

The pressure of steam introduced from an external steam boiler is pressured in a pressure vessel (2) having a water supply inlet (6) for introducing clean water and a high-quality steam outlet pipe (3) for taking out generated clean steam. In the steam generator (1) comprising a heat exchanger (9) for evaporating the water in the pressure vessel by exchanging heat with the water in the vessel,
The condensed water generated by the steam deprived of heat in the heat exchanger (9) is taken out and separated from the steam by the steam trap (10), and then the condensed water is supplied into the pressure vessel (2). The steam generator (1) characterized by having comprised as follows. A water level detection device (13) for automatically detecting the water level in the pressure vessel (2);
Based on the output signal of the water level detection device (13), the opening / closing operation of at least one of the water supply motor operated valve (14) and the drain motor operated valve (15) provided in the pressure container (2) is controlled, and the pressure container (2 ) A control device (16) for automatically adjusting the water level in
The steam generator (1) according to claim 1, characterized in that   There is provided a herb storage pot (17) through which clean steam taken out from the high-quality steam outlet pipe (3) of the pressure vessel (2) is passed, and the aromatic steam obtained by passing through the herb storage pot is stored in the sauna bathroom. Steam generating device (1) according to claim 1 or 2 for a steam sauna bath device, characterized in that it is configured to be discharged into the water.

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