EP1117964B1 - Steam generator with at least partly double-walled evaporation tank - Google Patents

Abstract

The invention relates to a steam generator comprising an evaporation tank and several heating elements (2). The evaporation tank consists of an evaporation vessel (1) and a removable limescale rectacle (4) positioned below same. The evaporation vessel (1) is configured as a double-walled vessel having an inner wall (11) and an outer wall (12) which define an outer chamber (13). The inner wall (11) has four inner water-flow openings (111) which connect the interior of the vessel with the outer chamber (13) and the outer wall (12) has outer water-flow openings (121, 122). Water is delivered to and withdrawn from the vessel via the outer flow openings (121, 122), the outer wall (13) and the inner flow opening (111).

Description

The present invention relates to a steam generator with an evaporation vessel and at least one Radiator.

Steam generators are used, for example, for air humidification used and usually comprise an evaporation vessel, that is partially filled with water. The water will with radiators, e.g. Electrodes or electrical resistors, heated and evaporated, whereby mineral salts precipitated be made from sludge from time to time the evaporation vessel must be removed. For this, for Refill water and sometimes for water level monitoring by a swimmer in a swimmer vessel outside of the evaporation vessel, the latter has at least a water passage opening that is common in his Floor is arranged.

A particularly when using very calcareous water big problem is the calcification and the rapid overgrowth the mostly relatively small water outlet or -Openings, often cleaning after a short time makes necessary. Become larger water openings used, the amount of blowdown can hardly be controlled over time and there is also a risk that the water to oscillate in the evaporation vessel shortly after draining starts.

To the time intervals between cleaning if possible attempts were made to keep the water passage openings large to be provided with facilities that clog quickly prevent. The use is known, for example of sieves with a variety of suitably arranged Openings and the pumping of air from below the openings to keep waterways clear, and Openings that are cleaned by moving parts. With The proposed solutions could, however, the maintenance cycles not satisfactorily for all water types be enlarged.

DE-A-26 42 911 describes a steam generator with an evaporation vessel and a radiator in which the Evaporation vessel partially double-walled with an inner wall and an outer wall is formed which is an outer chamber limit. The outer wall has an outer water passage opening on so the water supply into that Inside the vessel and taking water from the inside of the vessel via the outer water passage opening, the outer chamber and a gap between the inner wall and the outer wall he follows. This steam generator is the closest State of the art.

Given the problem of swift with certain water types Calcification of the water outlet openings in the previous ones known steam generators, the invention is the following Based on the task. A steam generator has to be created with an evaporation vessel with at least one water passage opening, that does not calcify or at least slows down than the water openings of the previous ones Steam generator.

This object is achieved by the steam generator according to the invention solved as defined in independent claim 1 is. Preferred variants result from the dependent claims.

The essence of the invention is that in one Steam generator with an evaporation vessel and at least the evaporation vessel at least partially double-walled with an inner wall and an outer wall is formed, which delimit an outer chamber. The inner wall at least one shows the inside of the vessel with the outer chamber connecting inner water passage opening and the Outside wall at least one outer water passage opening on, so that the water supply into the interior of the vessel and the withdrawal of water from the interior of the vessel via or at least one of the outer water openings that Outer chamber and the or at least one of the inner water passage openings he follows.

The inner or inner water openings that the Exposed to lime-discharging hot water inside the vessel are relatively large, so that they don't grow too quickly. The externally supplied Water flowing through the at least one outer water outlet into the outer chamber and from there through the at least one inner water passage opening The interior of the vessel penetrates and warms up during this time little that hardly any lime is excreted in the outer chamber becomes. Accesses the outer water outlet or openings therefore only very little lime, so that this is chosen smaller can be. In this way, the maintenance cycles of the steam generator can be enlarged without doing so Concessions to control the necessary from time to time Draining or to the stability of the water level must be made in the evaporation vessel.

In a preferred embodiment variant, the evaporation vessel comprises an evaporation tank, the one below Has opening, and a replaceable arranged below Lime receptacle with a filling opening, see above that excreted inside the evaporation tank Lime through the evaporation tank opening and the filling opening gets into the lime receptacle. The inner the evaporation tank is not in this way Filled with lime and the excreted lime has less be removed quickly. The limescale removal is also easier, especially if the lime container is replaced or is emptied before it is completely filled with lime is.

The double-walled part of the evaporation vessel can either on the evaporation container or on the lime receptacle or both.

Advantageously, there is an approximately horizontal one in the outer chamber or lime sedimentation surface inclined outwards, which in particular through the inside of part of the outer wall can be shaped. This lime sedimentation area begins Limescale through the at least one inner water passage flow into the outer chamber, and the in lime released even before the outer chamber or the outer water outlet openings.

Fig. 1 -

eine schematische, teilweise geschnittene Ansicht eines erfindungsgemässen Dampferzeugers;

Fig. 2 -

eine teilweise geschnittene Perspektivansicht eines Teils des Dampferzeugers von Fig. 1;

Fig. 3 -

eine teilweise geschnittene Perspektivansicht eines Isoliereinsatzes des Dampferzeugers von Fig. 1;

Fig. 4 -

eine Teilansicht eines erfindungsgemässen Dampferzeugers ähnlich Fig. 1, aber mit einem zusätzlichen Isolierteil; und

Fig. 5 -

eine Perspektivansicht eines Isolierteils des Dampferzeugers von Fig. 4.

The steam generator according to the invention is described in more detail below with reference to the accompanying drawings using an exemplary embodiment. Show it:

Fig. 1 -

is a schematic, partially sectioned view of a steam generator according to the invention;

Fig. 2 -

a partially sectioned perspective view of part of the steam generator of Fig. 1;

Fig. 3 -

a partially sectioned perspective view of an insulating insert of the steam generator of Fig. 1;

Fig. 4 -

a partial view of an inventive steam generator similar to Figure 1, but with an additional insulating part. and

Fig. 5 -

4 shows a perspective view of an insulating part of the steam generator from FIG. 4.

Figures 1 to 3

The steam generator shown comprises an evaporation vessel with an evaporation container 1 and a lime receptacle 4. The evaporation container 1 has a lid 15 on which several radiators protrude into the interior of the vessel 2, e.g. Resistance heating elements are attached, wherein only one is drawn here for the sake of clarity. The evaporation container 1 is about two thirds Water filled, while the water level 10 is not homogeneous due to the boiling water. The generated steam is discharged via a steam line 6.

The evaporation container 1 is double-walled with an inner wall 11 and an outer wall 12, the one Limit outer chamber 13 and has an opening 14 below on. The outer wall 12 is in the illustrated embodiment essentially cylindrical with a horizontal Lime sedimentation area 123 forming paragraph. The upper Part of the inner wall 11 is also cylindrical, while the lower part is funnel-shaped, making it more excreted and blasted off the inner wall 11 or the radiators 2 Lime slips off. The distance between the inner wall 11 and the outer wall 12 is approximately 10 mm in the upper part is bent outwards by bulges 113 and one guaranteed upper edge 114 of the inner wall 11. At the bottom Part of the limescale surface 123 extends to the inner wall 11, the latter two indentations 112 has a flow of water between the Edge of the limescale surface 123 and her. Below and above the limescale surface 123 is the outer chamber 13 continuously formed around the inner wall 11.

The inside of the evaporation vessel is over four inner ones Water passage openings 111 in the inner wall 11 with the outer chamber 13 connected. In the outer wall 12 are below the limescale settling area 123 two outer water openings 121, 122 arranged. The inner water openings 111 have a diameter of approx. 30 mm and therefore do not grow too quickly. The outside Water passage openings 121, 122 have a diameter from approx. 20 mm, so that on the one hand possible when draining entrained limestone can be washed out, on the other hand, there is no danger that after to blow the water in the evaporation vessel starts.

Inserted into the funnel-shaped part of the inner wall 11 is also a funnel-shaped insulating insert 3 two indentations 32 corresponding to the indentations 112 of the inner wall 11 are formed. This insulation insert 3 insulates the outer chamber 13 in the area of the lime sedimentation surface 123 and the outer water openings 121, 122 thermally against the inside of the vessel and ensures that the water temperature in this area is less than Is 50 ° C. The insulating insert 3 shown is for this purpose waterproof blow-molded part with an air-filled cavity 31 trained, but could also be a waterproof, welded, multi-part plastic molded part with one Cavity, a waterproof, welded, multi-part Metal part with a cavity, a thick-walled part, in particular made of elastomer, or with a plastic injection molded part gaseous deposits, especially air deposits, be or consist of a foam-like material.

The outer wall 12 includes below the lime sedimentation surface 123 a connecting piece 124, which with the rest of the outer wall 12 is firmly connected, with an annular seal 125 tightness is guaranteed. At the connecting piece 124 is the exchangeable lime receptacle 4 with filling opening 41 arranged in which the excreted in the evaporation tank 1 and from the inner wall 11 or the radiators 2 chipped lime accumulates. The lime receptacle 4 has two cams 42, which are attached to it in FIG two holes two descending from a platform 5 Holding parts 51 are suspended.

At the water passage opening 121 there is a water addition -Remission device 7 and at the water passage opening 122 a water level monitoring device 8 is connected.

The water level monitoring device 8 comprises one of the outer water passage opening 122 to a float housing 82 leading water pipe 81 and one from the float housing 82 pressure equalization line leading to the steam line 6 84. In the float housing 82 is a float 83, which indicates the height of the water level 10, the same in the float housing 82 and in the evaporation vessel is because the inside of the float housing 82 over the Water pipe 81, the outer water passage opening 122, the outer chamber 13 and the inner water passage openings 111 in connection with the interior of the evaporation vessel stands. The float position can be recorded electronically and can be used to control the water level 10.

The water addition and removal device 7 comprises one from the outer water passage opening 121 to one above open inlet cup 73 leading water pipe 71, in the a pump 72 is arranged to allow water to flow through the exterior Water passage opening 121, the outer chamber 13 and the inner water passage openings 111 from the inside of the vessel can be pumped out. Leads to the inlet cup 73 a water supply line 74 with a valve 75 and from Inlet cup 73 away from a water outlet line 76.

When draining, that which flows out of the evaporation vessel arrives Water through the inner water openings 111 from the inside of the vessel into the outer chamber 13 and from from there via the outer water passage opening 121 into the Water addition and removal device 7. Any lime deposits or limestone chippings caused by the inner Water passage openings 111 get into the outer chamber 13, are deposited on the limescale surface 123. To the Outer water passage openings 121, 122 thus reach hardly any lime, so this despite the relatively small diameter not overgrow.

To replace the water evaporating during operation is over using the static water column pressure the water pipe 71, the outer water passage opening 121, the outer chamber 13 and the inner water passage openings 111 refilled water into the interior of the vessel, whereby this in the outer chamber 13 does not exceed the lime precipitation temperature heated from approx. 50 ° C and therefore none Lime is released.

The following definition applies to the further description. are in a figure for the sake of graphic clarity, reference numerals included, but in the directly associated description text not explained, will be mentioned on their mention referred to in previous figure descriptions.

Figures 4 and 5

The steam generator shown in Fig. 4 is constructed similarly like that shown in Fig. 1, but points between the inner wall 11 and the outer wall 12 per inner water passage opening 111 an insulating part 9 for thermal insulation the outer chamber 13 to the inside of the vessel. The Insulating parts 9 each extend from the relevant one inner water passage opening 111 down to slightly below the height of the top edge of the funnel-shaped insulating insert 3. You isolate the outer chamber 13 above the lime sedimentation surface 123 thermally against the interior of the vessel out. The insulating part 9 shown is for this purpose as waterproof Blow part formed with an air-filled cavity 91, but could also be a waterproof, welded, multi-part plastic injection molded part with a cavity, a waterproof, welded, multi-part metal part with a cavity, a thick-walled part, in particular from Elastomer, or a plastic molded part with gaseous Storage, especially air storage, be or consist of a foam-like material. It points one in the relevant inner water passage opening 111 extending anchoring part 92 and a corresponding of the inner wall 11 bent shell part 93.

• Anstatt zur thermischen Isolierung der Aussenkammer 13 gegen das Gefässinnere einen separaten Isoliereinsatz 3 vorzusehen, kann auch die Innenwand 11 im gewünschten Bereich besser isolierend ausgestaltet werden, beispielsweise durch Einschluss eines Hohlraums, dickwandige Ausbildung und/oder Verwendung eines geeigneten Materials.
• Die äusseren Wasserdurchlassöffnungen 121, 122 können anstatt unterhalb der Kalkabsetzfläche 123 auch im Bereich der letzteren angeordnet sein.
• Anstelle eines Isolierteils 9 pro innerer Wasserdurchlassöffnung 111 kann ein einziges, sich rund um die Innenwand 11 herum erstreckendes Isolierteil vorgesehen sein.

In addition to the previously described steam generator according to the invention, further design variations can be realized. Here are also explicitly mentioned:

• Instead of providing a separate insulating insert 3 for the thermal insulation of the outer chamber 13 from the interior of the vessel, the inner wall 11 can also be made better insulating in the desired area, for example by including a cavity, thick-walled design and / or using a suitable material.
• The outer water passage openings 121, 122 can also be arranged in the area of the latter instead of below the lime sedimentation surface 123.
• Instead of one insulating part 9 per inner water passage opening 111, a single insulating part extending around the inner wall 11 can be provided.

Claims (13)

1. A steam generator with an evaporation tank (1, 4) and at least one heating body (2), the evaporation tank (1, 4) having an at least partially double-walled design with an inner wall (11) and an outer wall (12) which bound an outer chamber (13), the outer wall (12) having at least one outer water passage opening (121, 122), so that the water supply to the inside of the tank and the water withdrawal from the inside of the tank takes place through the outer water passage opening or at least one of the outer water passage openings (121, 122) and the outer chamber (13), characterized in that the inner wall (11) has at least one inner water passage opening (111) connecting the inside of the tank to the outer chamber (13), so that the water supply to the inside of the tank from the outer chamber (13) and the water withdrawal from the inside of the tank to the outer chamber (13) takes place through the inner water passage opening or at least one of the inner water passage openings (111).
2. The steam generator as claimed in claim 1, characterized in that the distance between the inner wall (11) and the outer wall (12) is mostly between 3 and 30 mm, preferably approximately 10 mm.
3. The steam generator as claimed in claim 1 or 2, characterized in that the evaporation tank comprises an evaporation vessel (1), which has an opening (14) at the bottom and, arranged underneath it, an exchangeable lime receptacle (4) with a filling opening (41), so that lime precipitated inside the evaporation vessel (1) passes through the evaporation vessel opening (14) and the filling opening (41) into the lime receptacle (4).
4. The steam generator as claimed in claim 3, characterized in that a double-walled part of the evaporation tank is located on the evaporation vessel (1).
5. The steam generator as claimed in claim 3 or 4, characterized in that the double-walled part of the evaporation tank with the outer wall passage opening or openings is located on the lime receptacle (4).
6. The steam generator as claimed in one of claims 1 to 5, characterized in that, in the region of the outer water passage opening or openings (121, 122), the outer chamber (13) is thermally insulated relative to the inside of the tank in such a way that the water temperature in this region is less than 60°C, in particular less than 50°C.
7. The steam generator as claimed in claim 6, characterized in that the thermal insulation of the outer chamber (13) relative to the inside of the tank takes place by means of an insulation insert (3) which preferably comprises

   a) a water-tight pneumatic part with a cavity;

   b) a water-tight, welded, multi-part plastic injection part with a cavity;

   c) a water-tight, welded, multi-part metal part with a cavity;

   d) a thick-walled part, in particular in elastomer;

   e) a plastic injection part with gaseous inclusions, in particular air inclusions; or

   f) a cellular substance type of material.
8. The steam generator as claimed in one of claims 1 to 7, characterized in that the lower part of the inner wall (11) and the insulation insert (3), if present, have a funnel-shaped design.
9. The steam generator as claimed in one of claims 1 to 8, characterized in that an approximately horizontal or outwardly inclined lime deposition surface (123), which can be formed, in particular, by the inside of a part of the outer wall (12), is arranged in the outer chamber (13).
10. The steam generator as claimed in claim 9, characterized in that the outer chamber (13) is continuous around the inner wall (11) below the lime deposition surface (123) and the outer water passage opening or openings (121, 122) are arranged in this region.
11. The steam generator as claimed in claim 9 or 10, characterized in that the lime deposition surface (123) reaches as far as the inner wall (11) and the inner wall (11) and the insulation insert (3), if present, have at least one indentation (32, 112) which permits a flow of water between the edge of the lime deposition surface (123) and the inner wall (11).
12. The steam generator as claimed in one of claims 1 to 11, characterized in that at least one insulating part (9), for the thermal insulation of the outer chamber (13) relative to the inside of the tank, is arranged between the inner wall (11) and the outer wall (12), which insulating part (9) extends from the inner water passage opening or openings (111) downward and preferably comprises

    a) a water-tight pneumatic part with a cavity;

    b) a water-tight, welded, multi-part plastic injection part with a cavity;

    c) a water-tight, welded, multi-part metal part with a cavity;

    d) a thick-walled part, in particular in elastomer;

    e) a plastic injection part with gaseous inclusions, in particular air inclusions; or

    f) a cellular substance type of material.
13. The steam generator as claimed in one of claims 1 to 12, characterized in that the inner water passage opening or water passage openings (111) have a diameter between 10 and 50 mm, in particular between 20 and 40 mm, and the outer water passage opening or water passage openings (121, 122) have a diameter between 10 and 40 mm, in particular between 15 and 25 mm.

Images