EP2554805A2 - Steam utilisation plant - Google Patents

Abstract

The plant (1) has a cylinder-shaped overflow mixing device (7) connected with a liquid line (6) or liquid reservoir (9) of a steam generator (2) via a liquid inlet (8) for supplying liquid into the overflow mixing device. The mixing device is connected with an overpressure steam line that contains an overflow valve (5), and is connected with an energy recycling device (12) via a liquid outlet (11). Mixture of steam with the liquid flowing through a mixing chamber (13) is provided in the mixing chamber, where the steam flows through the valve. The mixing device is thermally insulated.

Description

The present invention relates to a steam utilization plant which has at least one steam generator, at least one steam line extending from the steam generator with a safety overpressure valve and an overflow valve and at least one liquid line feeding the at least one steam generator.

Steam utilization systems of the type mentioned are used for example in laundries. In this case, steam is generated as a heat transfer medium, wherein the steam for heating washing machines, tumble dryers and laundry iron is used. To operate the tumble dryers and laundry iron higher temperatures are needed. Therefore, the generated steam is typically used first for heating the clothes dryers and the laundry mangles. The vapor condensing after its use under high pressure is then fed to a flash vessel in which the condensate partially evaporates to vapor vapor. The Brüdendampf is then the heat carrier in which most of the heat energy from the condensate is concentrated. The broth steam is used, for example, to heat the wash water in a washing machine designed as a wash tube. Such a washing machine used in laundries is for example in the document EP0088052 B2 described.

In the prior art, the flash vessel is coupled to a brine steam line. To the Brüdendampfleitung also a safety valve is coupled, which opens at an overpressure and releases the overpressure for safety reasons to the outside. Furthermore, an overflow valve is coupled to the Brüdendampfleitung, which opens already at a lower pressure than the safety valve and thus releases time before the safety valve, the excess pressure into the open. The overflow valve protects the safety valve and ensures its safe function.

When switching overpressure valves, so-called steam blows occur, which on the one hand represent a strong noise nuisance and on the other hand also a material load for the valves. The overflow valves are therefore usually designed so that they work in certain pressure ranges as pressure control valves and steam blows rarely occur. In this function of the overflow valves steam flows into the atmosphere. The heat energy bound in the overflowing steam is thus lost in the prior art for further use.

It is therefore the object of the present invention to propose a steam utilization system in which the system energy is better utilized.

The object is achieved by a steam utilization plant of the above-mentioned type, which is characterized in that the steam utilization plant comprises a Überströmmischvorrichtung to the first via a liquid inlet to the liquid line or a liquid reservoir of the at least one steam generator for supplying a liquid in the Überströmmischvorrichtung, the second is connected to an overpressure valve containing the overpressure steam line and thirdly via a liquid outlet of the Überströmmischvorrichtung with an energy recovery device for the steam utilization plant, wherein the Überströmmischvorrichtung has a mixing space in which a mixing of the effluent through the overflow valve steam is provided with the liquid flowing through the mixing space.

1. 1. einen Flüssigkeitseingang,
2. 2. einen Dampfeingang und
3. 3. einen Flüssigkeitsausgang.

Thus, the steam utilization system according to the invention has an overflow mixing device, in which steam flowing out through the overflow valve is introduced into a liquid, thereby heating the liquid. The Überströmmischvorrichtung has for this purpose three connections:

1. 1. a fluid inlet,
2. 2. a steam inlet and
3. 3. a liquid outlet.

In the overflow mixing device, a liquid or a condensate flows from the liquid inlet to the liquid outlet. The liquid inlet can be integrated at different points in the steam utilization system. Preferably, however, the liquid inlet is not connected to a cold liquid, but to an already warm liquid, which is further heated by the steam introduced, so that a liquid with a high temperature can be made available at the liquid outlet of the overflow mixing device, which is subsequently suitably usable.

A suitable source of liquid is the liquid reservoir of a flash vessel, which serves as a steam generator for Brüdendampf. The liquid present in the liquid reservoir is a condensate which has been deprived of heat energy by vaporization of broth steam, which is then fed back via the overflow valve to this condensate, which is introduced into the overflow mixing device via the liquid inlet. That is, in the Überströmmischvorrichtung the overflowing steam is added to the effluent condensate again. By this connection, there is a coupling between the amount of steam and the amount of liquid, so that an optimum balance between the amount of steam and the amount of liquid in the operation of the cross-flow mixing device can be achieved. As a result, the condensate (liquid) heated by steam in the overflow apparatus can be made available to downstream consumers with almost the same energy content as the condensate introduced into the steam generator. In principle, no energy is lost.

In order to achieve this, a mixing space is provided in the overflow mixing device, in which the steam is mixed with the liquid. At the liquid outlet of the overflow mixing device is then further heated by the liquid liquid available. The liquid outlet is also connected to an energy recovery device, which advantageously uses the heated liquid or the condensate. An energy recycling device may, for example, be a mixing chamber for introducing the heated liquid into fresh supplied soft water, but it may also be a heat exchanger or a washing machine.

In an advantageous embodiment of the steam utilization system according to the invention, the overflow mixing device is designed such that the liquid flows through the overflow mixing device in a liquid flow direction and the steam introduction into the overflow mixing device is formed transversely to the liquid flow. By this arrangement, one achieves a particularly good mixing of the vapor into the liquid. Furthermore, in this way, the connections of the Überströmmischvorrichtung be service-friendly spaced from each other, and the Überströmmischvorrichtung can be made compact.

Furthermore, it is in the steam utilization system according to the invention advantageous if the Überströmmischvorrichtung is cylindrical. Cylindrical housing parts are inexpensive to produce from pipe sections and forces resulting from an operating pressure are distributed evenly on the cylinder.

In a preferred embodiment of the steam utilization system according to the invention, the cylinder of the cylindrical overflow mixing device is connected at the edges of the cylinder jacket surface to first sides of a first and a second conical funnel, wherein a second side of the first conical funnel for connection to the liquid inlet and a second side of the second conical funnel are provided for connection to the liquid outlet. The mixing chamber in the overflow mixing device has a larger diameter than the incoming and outgoing fluid lines. For the formation of the mixing chamber with connections for the liquid lines therefore suitable transitions are required, which are realized in this particular embodiment by the conical funnel, which can be conveniently welded to cylinders or tubes.

In a particularly favorable embodiment of the steam utilization system according to the invention, the overflow mixing device has such dimensions that the liquid in the overflow mixing device has a flow velocity of about 1 m / s. The Überströmmischvorrichtung should on the one hand have the most compact dimensions, but on the other hand, but a complete mixing of the vapor with the liquid in the mixing device to be achieved. In the design of the overcurrent mixing device is to find an optimum between the two requirements. This optimum was achieved when the overflow mixing device was designed for a flow rate of about 1 m / s.

According to a preferred embodiment of the steam utilization system according to the invention, a nozzle lance extending in the liquid flow direction is provided in the overflow mixing device with nozzles which are arranged such that the steam flows via the nozzle lance and the nozzles into the mixing chamber. Through the nozzle lance The steam can be distributed particularly well within the mixing chamber and discharged through the nozzles evenly into the mixing chamber. In this way, an efficient mixing of the gas with the liquid is achieved so that the overflow mixing device can be operated independently of position. For example, the overflow mixing device may be installed with a vertically or horizontally provided liquid flow direction.

It has proved to be particularly suitable to form the nozzle lance in the form of an angle in the steam utilization system according to the invention, wherein a first leg of the angle is performed by a wall of the overflow mixing device and connected to the wall of the Überströmmischvorrichtung at the implementation site. A second leg of the nozzle lance is arranged along a longitudinal axis of the overflow mixing device aligned centrally in the mixing space in a liquid flow direction. By forming the nozzle lance as an angle, the second leg of the nozzle lance containing the nozzles can be positioned centrally or at another suitable position in the mixing space. The leg, which is arranged transversely to the liquid flow direction, assumes the functions of mechanically fastening the nozzle lance to the wall of the overflow mixing device and supplying the gas to the nozzles of the nozzle lance.

In a favorable embodiment of the steam utilization system according to the invention, the nozzles have a diameter of 3 mm to 4 mm. With nozzles of this diameter, a particularly good mixing of gas and liquid can be achieved.

Furthermore, in a steam utilization installation according to the invention, the number of nozzles is preferably selected to be so high that a steam exit speed of 30 m / s to 40 m / s is achieved from the nozzles. This steam outlet speed has also proved to be advantageous for a good mixing of steam and liquid.

In one embodiment of the steam utilization system according to the invention, the overflow mixing device is vertically aligned in the steam utilization system and the liquid flow direction in the overflow mixing device is provided from bottom to top. In principle, most embodiments of Überströmmischvorrichtungen Although it can be installed in any position, the vertical orientation of the overflow mixing device with a liquid flow from bottom to top is advantageous under different operating conditions. Such conditions of use can be given for example at low Dampfüberströmmengen or small, the liquid flow driving differential pressures on the liquid line.

According to an advantageous embodiment of the steam utilization system according to the invention, the overflow mixing device is thermally insulated. Due to the thermal insulation, a high thermal efficiency of the steam utilization system is achieved.

In a preferred embodiment of the steam utilization plant according to the invention, the steam generator of the steam utilization plant has a flash vessel for the supply of Brüdendampf, wherein in the flash tank, the introduction of a pressurized condensate, a partial evaporation of the condensate at a medium pressure to Brüdendampf and the discharge of non-evaporated condensate is provided from the liquid reservoir via the liquid inlet to the overflow mixing device. Experience has shown that a large amount of steam is lost at the overflow valve of a flash vessel for generating broth steam and it is particularly desirable to utilize this overflow steam by introducing it into an overflow mixing device.

However, the use of the inventively provided Überströmmischvorrichtung is not bound to this application example, in other embodiments of the invention, other, previously unused steam volumes of Überströmmischvorrichtung can be supplied. In the application example in which the exhaust vapor derived via the overpressure valve is introduced into the Überströmmischvorrichtung, it is also particularly advantageous to use the liquid inlet of the Überströmmischvorrichtung with the liquid reservoir in the expansion vessel in which arises in relaxation of condensate Brüdendampf. With this use, it is ensured that there is no overheating and evaporation of the liquid, since only a small part of the Brüdendampfes, which is generated in the expansion vessel, is returned to the condensate. This condensate is capable of absorbing the thermal energy that has been unused in the prior art via the spill valve. To technically implement this embodiment, are only a few changes to an existing steam utilization system required, while on the other hand result from such a conversion very high financial savings in the operation of the converted steam utilization plant.

The water further heated in the overflow mixing device by the introduction of steam can be used differently in various configurations of the steam utilization system according to the invention. Thus, the energy recycling device can have a feedwater pre-heating vessel for the steam utilization system or else a further expansion vessel of the steam utilization system. That is, in one embodiment, the liquid heated in the overflow mixing device is used to heat feed water in a feedwater pre-heat vessel. In another embodiment of the steam utilization system according to the invention, the heated liquid is introduced into a further expansion vessel. In any case, the liquid flow follows a pressure gradient existing in the steam utilization plant.

Figur 1

schematisch einen möglichen Aufbau einer erfindungsgemäßen Dampfnutzungsanlage zeigt; und

Figur 2

schematisch ein Ausführungsbeispiel einer in einer erfindungsgemäßen Dampfnutzungsanlage verwendbaren Überströmmischvorrichtung zeigt.

Preferred embodiments of the present invention, their structure, function and advantages are explained in more detail below with reference to figures, wherein

FIG. 1

schematically shows a possible construction of a steam utilization system according to the invention; and

FIG. 2

schematically shows an embodiment of a usable in a steam utilization plant according to the invention Überströmmischvorrichtung.

FIG. 1 schematically shows a possible structure of a steam utilization system 1 according to the invention. In other, not shown embodiments of the steam utilization system according to the invention may also be a different structure than the one in FIG. 1 is shown used.

Core component of the steam utilization system 1 according to the invention is the in FIG. 1 designated by the reference numeral 25 complex plant. The plant complex 25 has a steam generator 2, which is formed in the embodiment shown in the form of a flash vessel 23. The expansion vessel 23 is in the embodiment shown substantially cylindrical and arranged vertically erect, so that the cylinder surface of the expansion vessel 23 is arranged laterally. The steam generator 2 is coupled to a liquid line 6, via which the steam generator 2 is supplied with a liquid in the form of a hot, pressurized condensate. The direction of the condensing line is in FIG. 1 in the liquid line 6 schematically represented by corresponding arrows.

The pressurized hot liquid (condensate) collects in the expansion vessel 23 of the steam generator 2 in the lower region in a liquid reservoir 9. In this case, above the liquid reservoir 9 steam 26, that is, the so-called Brüdendampf, which also increased under atmospheric pressure Pressure is. This steam 26 is discharged via a steam line 3 from the steam generator 2 in the direction schematically shown by the arrow in the steam line 3.

On the steam line 3, a safety pressure relief valve 4 is initially provided, via which steam 26, the pressure of which exceeds a predetermined system overpressure, is discharged into the open according to the arrow provided on the safety pressure relief valve 4.

The safety overpressure valve 4 and the liquid reservoir 9 of the expansion vessel 23 are each coupled to a drainage line 36.

In the flow direction of the steam 26 in the steam line 3, the safety pressure relief valve 4 downstream of a spill valve 5 is provided. The overflow valve 5 already opens below a vapor pressure at which the safety overpressure valve 4 would open. In this way, steam under overpressure 26 is first removed via the overflow valve 5 in accordance with the direction provided by the arrow on the overflow valve 5.

The steam flowing through the overflow valve 5, which is under excessively high pressure, is supplied through an overpressure steam line 10 to an overflow mixing device 7, which in FIG FIG. 2 is shown again by way of example in an enlarged view.

The overflow mixing device 7 is in the in FIG. 1 embodiment shown formed cylindrical. Although the overflow mixing device 7 can be arranged according to the invention in any constellation, it is in the in FIG. 1 shown example provided as an upright cylinder. In this case, the initiation of the pressurized steam 26 takes place by means of the overpressure steam line 10 into a cylinder jacket surface 16 of the overflow mixing device 7.

At the lower and upper edges 14, 15 of the cylinder jacket surface 16 of the overflow mixing device 7 are in the in FIG. 1 illustrated embodiment conical funnel 17, 18 is provided. In this case, the first conical funnel 17 provided below forms a connection with a liquid inlet 8 of the overflow mixing device 7. A condensate line 27, which connects the liquid reservoir 9, which is formed in the lower part of the expansion vessel 23 of the steam generator 2, to the liquid inlet 8 of the overflow mixing device 7, opens into the liquid inlet 8. The direction of flow of the condensate within the condensate line 27 is in FIG. 1 schematically illustrated by a provided on the condensate line 27 arrow.

The second conical funnel 18 provided at the top of the overflow mixing device 7 forms a connection to a liquid outlet 11 of the overflow mixing device 7. The liquid outlet 11 is, as shown schematically in FIG FIG. 1 is shown connected to a further liquid line 6 ', which is provided for feeding a power recycling device 12.

In the in FIG. 1 illustrated embodiment, the energy recovery device 12 is a renewed plant complex, consisting of a further steam generator 2 'with a corresponding expansion vessel 23' and a liquid reservoir 9 ', a safety relief valve 4', an overflow valve 5 'and another Überströmmischvorrichtung 7', these elements to the same Cooperate as described above with respect to the plant complex 25. The same or similar reference numerals designate the same or similar elements of the steam utilization system 1.

In principle, however, it is also possible that the liquid line 6 'directly, as it is in FIG. 1 is schematically represented by the line 6 ", leads to a feedwater tank 24, which in turn coupled to a feedwater preheating unit or is part of such a feedwater preheating unit.

In the in FIG. 1 illustrated embodiment, a degasser 28 is provided on the feedwater tank 24, via which steam which evaporates from a liquid reservoir within the feed water tank 24 upwards, can be discharged into the open. The feed water tank 24 is subsequently, as indicated schematically by the arrows in the outgoing from the feed water tank 24 output line 29, connected via feedwater pumps 30 with a steam boiler 31. From the steam boiler 31 steam is supplied via a line 32 in the direction of the direction arrow shown schematically in the line 32 to a steam consumer 37. Condensate, which is generated in this steam consumer 37, is fed to the steam generator 2 via the above-described line 6.

Thus, the in FIG. 1 schematically represented steam utilization system according to the invention 1 three pressure levels on: namely an existing on the steam consumer 37 first pressure stage 33, the emerging from the plant complex 25 post-steam (reduced second pressure stage 34) and emerging from the energy recovery device 12 post-steam (reduced third pressure stage 35).

The emerging from the expansion vessel 23 of the plant complex 25 Brüdendampf can be used, for example, for feeding of ironing and / or ironing stations. Brüdendampf with lower pressure, as for example, the energy recovery device 12 of the steam utilization system 1 shown in Figure 12 can be removed, for example, can be used to power washing machines.

FIG. 2 schematically shows a possible structure of a usable in a steam utilization system 1 invention overflow mixing device. 7

As already stated above, the overflow mixing device 7 in the embodiment shown has a cylindrical container, in the interior of which there is a mixing space 13 is formed for a mixing of steam 26 and a liquid or a condensate. For this purpose, a nozzle lance 19 is provided with nozzles 20 provided therein within the mixing chamber 13. In the in FIG. 2 illustrated embodiment, the nozzle lance 19 is formed in the form of an angle, wherein a first leg 21 of the angle is performed by a wall 22 of the Überströmmischvorrichtung 7 and connected at the implementation site with the wall 22 of the Überströmmischvorrichtung 7. A second leg 38 of the nozzle lance 19 is arranged along a longitudinal axis of the overflow mixing device 7 aligned centrally in the mixing space 13 in a liquid flow direction A. In other, not shown embodiments of the present invention, the nozzle lance 19 may also be designed differently. In principle, more than one nozzle lance 19 can be used.

The spaced apart in the nozzle lance 19 and circumferentially seen nozzles 20 have in the embodiment shown a diameter of 3 mm to 4 mm. In other, not shown embodiments of the present invention, other nozzle diameters can be used.

In addition, in the in FIG. 2 illustrated embodiment, the number of nozzles 20 selected so high that a steam exit velocity of 30 m / s to 40 m / s is achieved from the nozzle 20. Depending on the application, the number of nozzles and the steam outlet speed can be varied according to the invention.

In the FIG. 2 shown oversampling device 7 is thermally insulated, it may not necessarily be in other embodiments of the invention.

Furthermore, the overflow mixing device 7 has an input and an output in the form of conical funnels 17, 18. In the exemplary embodiment shown, the liquid or the condensate flows through the overflow mixing device 7 at a speed of approximately 1 m / s. The inner diameter of the overflow mixing device 7 is correspondingly designed so that a flow rate of the liquid or the condensate is set, which is less than, 0 m / s.

The Überströmdampf exiting from the nozzles 20 immediately mixed within the mixing chamber 13 with the passing condensate or the liquid. Without Steam shocks and associated material stress leaves the condensate or the liquid via the conical exit the Überströmmischvorrichtung 7 and can reach the next consumer.

As mentioned above, the Überströmmischvorrichtung 7 can be mounted in any mounting position. For low flow rates and differential pressures of less than 1 bar, however, vertical installation with flow direction upwards is recommended.

The Überströmmischvorrichtung 7 can be retrofitted easily in existing systems.

Claims (13)

Steam utilization plant (1) comprising at least one steam generator (2), at least one steam line (3) emanating from the steam generator (2) with a safety overpressure valve (4) and an overflow valve (5) and at least one liquid line feeding the at least one steam generator (2) (6), characterized in that the steam utilization system (1) has an overflow mixing device (7) which is connected first to the liquid line (6) or a liquid reservoir (9) of the at least one steam generator (2) via a liquid inlet (8) Supply of a liquid into the overflow mixing device (7), to the second with an overpressure mixing valve (5) containing overpressure steam line (10) and third via a liquid outlet (11) of the Überströmmischvorrichtung (7) with an energy recovery device (12) for the steam utilization system (1) wherein the overflow mixing device (7) has a mixing space (13 ), in which there is provided a mixing of the vapor flowing out through the overflow valve (5) with the liquid flowing through the mixing chamber (13). Steam utilization system according to claim 1, characterized in that the overflow mixing device (7) is designed such that the liquid flows through the overflow mixing device (7) in a liquid flow direction (A) and the steam introduction into the overflow mixing device (7) is formed transversely to the liquid flow direction (A) is. Steam utilization plant according to claim 1 or 2, characterized in that the overflow mixing device (7) is cylindrical. A steam utilization installation according to claim 3, characterized in that the cylinder of the cylindrically shaped overflow mixing device (7) is connected at the edges (14, 15) of the cylinder jacket surface (16) to first sides of a first and a second conical funnel (17, 18) a second side of the first conical funnel (17) for connection to the liquid inlet (8) and a second side of the second conical funnel (18) for connection to the liquid outlet (11) are provided. Steam utilization plant according to at least one of the preceding claims, characterized in that the overflow mixing device (7) has dimensions such that the liquid in the overflow mixing device (7) has a flow velocity of 1 m / s. Steam utilization plant according to at least one of the preceding claims, characterized in that in the overflow mixing device (7) there is provided a nozzle lance (19) with nozzles (20) extending in the liquid flow direction (A), which are arranged such that the steam is conveyed via the nozzle lance (10). 19) and the nozzles (20) flows into the mixing chamber (13). Steam utilization plant according to claim 6, characterized in that the nozzle lance (19) is formed as an angle, wherein a first leg (21) of the angle through a wall (22) of the overcurrent mixing device (7) performed and at the implementation site with the wall (22) the overflow mixing device (7) is connected and a second leg (38) of the nozzle lance (19) along a in a liquid flow direction (A) centrally in the mixing chamber (13) aligned longitudinal axis of the Überströmmischvorrichtung (7) is arranged. Steam utilization installation according to claim 6 or 7, characterized in that the nozzles (20) have a diameter of 3 mm to 4 mm. Steam utilization system according to at least one of claims 6 to 8, characterized in that the number of nozzles (20) is selected so high that a steam exit velocity of 30 m / s to 40 m / s from the nozzles (20) is achieved. Steam utilization plant according to at least one of the preceding claims, characterized in that the overflow mixing device (7) in the steam utilization plant (1) is vertically aligned and a liquid flow direction (A) is provided in the overflow mixing device (7) from bottom to top. Steam utilization installation according to at least one of the preceding claims, characterized in that the overflow mixing device (7) is thermally insulated. Steam utilization plant according to at least one of the preceding claims, characterized in that the steam generator (2) of the steam utilization plant (1) comprises a flash vessel (23) for providing vapor vapor, wherein in the expansion vessel (23) the introduction of a pressurized condensate, a partial Evaporation of the condensate at a mean pressure to Brüdendampf and the discharge of unevaporated condensate from the liquid reservoir (9) via the liquid inlet (8) to the Überströmmischvorrichtung (7) is provided. Steam utilization installation according to at least one of the preceding claims, characterized in that the energy recycling device (12) has a feedwater preheating unit for the steam utilization installation (1) or a further expansion vessel (23) of the steam utilization installation (1).

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