EP4093949B1 - Assembly comprising a steam saturator and method for operating an assembly of this type - Google Patents

Description

The present invention relates to an arrangement comprising a steam saturator for generating saturated steam and a device for replenishing the liquid evaporated in the steam saturator, the steam saturator comprising a steam inlet via which steam is supplied to the steam saturator, the steam saturator comprising a steam outlet for the saturated steam generated, the steam saturator comprises a condensate return and wherein a liquid level of condensate is maintained in the lower region of the steam saturator, which is in fluid communication with the condensate return, the condensate return being connected to the device for making up the evaporated liquid.

State of the art

Saturated steam is used in many processes because it has two advantages over superheated steam: Firstly, the temperature is directly linked to the pressure, so that the temperature can also be regulated very well using pressure control. Second, saturated steam is more suitable for heating other fluids in heat exchangers because upon contact with cooler surfaces it can condense immediately with high heat transfer coefficients. With superheated steam, on the other hand, it must first be cooled down to the saturation temperature with lower coefficients before condensation begins.

Saturated steam is either prepared directly in steam generators or produced from superheated steam in steam saturators. For example, is off EP 1 300 630 A1 a steam generator for sterilizing medical devices is known, in which water is converted directly into superheated steam in a circuit, which is condensed in a heating coil and returned as water. With the help of the heating coil, water is converted into saturated steam in a sterilization chamber, which is used to sterilize medical devices. However, since there are also applications for superheated steam and the transport of superheated steam offers advantages, a steam saturator is usually only used where saturated steam is actually needed.

A steam saturator usually consists of a pressure vessel that is partially filled with liquid (steam condensate or boiler feed water). The container can be designed standing or lying down. Below the liquid level there is a steam distributor, through which the superheated steam is introduced into the liquid. Pressure maintenance ensures that sufficient amounts of superheated steam are fed in to maintain the desired process pressure on the saturated steam side. Since the injected steam has to flow through the liquid under a defined pressure, it emerges from the liquid surface as saturated steam under exactly this pressure and can be withdrawn from the pressure vessel and directed to the consumers.

As long as the steam saturator is operated with a sufficiently high liquid level, the generation of saturated steam is ensured. The steam saturator can be relatively easily equipped with safety devices for excess temperature and pressure as well as high/low filling levels.

However, as part of the liquid contained in the steam saturator evaporates due to the introduction of superheated steam, the filling level decreases. This liquid must be replenished in order to maintain the steam saturator's intended operation and to protect downstream systems from excessively high steam temperatures. This is particularly important in applications where excessive steam temperatures can damage a product or pose safety risks, such as ammonium nitrate.

Up to now, make-up has been implemented in two different ways: In the case of steam saturators that only supply one consumer, for example the concentrator of an ammonium nitrate plant, the condensate from the consumer can be returned directly to the steam saturator. The steam saturator then has a drain and/or overflow through which the excess condensate can leave the steam saturator/consumer system again. The previous alternative consists of a condensate line that refills the steam saturator either via an external pressure line with steam condensate or boiler feed water or an internal system return of steam condensate via the steam condensate pumps.

For make-up with an external source (e.g. a boiler feed water pressure line), the presence of this line and an external pressure source is required, as well as an automatic valve to control the fill level in the steam saturator. When supplying steam condensate from pumps internal to the system, these pumps must be in operation and must provide the necessary delivery pressure in order to be able to deliver into the pressurized steam saturator. These pumps become more expensive to purchase and operate - for small amounts of steam condensate that has to be returned to the steam saturator. An automatic valve must also be used here.

From the DE 27 18 927 A1 a steam saturator for textile finishing devices is known, the steam saturator here being designed as a standing container and having a conical bottom part in which the water not absorbed by the steam collects. In order to maintain a constant bath level in this conical bottom part, a line with a float drain opens into the lower part of the container. The respective bath level can be read on a water level indicator. Excess water can be drained off via a drain valve at the lowest point of the container. The excess water can be fed to a pump via a pipe and then circulated via valves and thus returned to the container.

From the DE 2046753 A1 a process and a system for the desulfurization of hot pressurized gases are known. A gas containing H ₂ S and water vapor is cooled and passed through an absorption tower in which H ₂ S is washed out and then flows to a steam saturator in which it is warmed up by a liquid heated in a cooler and saturated with steam. Circulating water is used for saturation, which is self-condensate from two coolers. The inherent condensate is partially removed and the amount of water required to supplement the circuit is partially removed via a line, fed to a scraper and then fed into the steam saturator via a circuit line in the upper area. The water from the circuit is evaporated into the clean gas in the steam saturator. In this known system there is no correlation between a fill level of the steam condensate in the steam saturator and the liquid level in the coolers. Here too, measurement and control devices are necessary to determine what volume of condensate is necessary to supplement the amount of water required for make-up. In addition, the system used here is quite complex.

Description of the present invention

The object of the present invention is to provide an arrangement with a steam saturator with the features mentioned at the outset, in which the condensate evaporated in the steam saturator is replenished virtually automatically.

The solution to the aforementioned problem is provided by an arrangement comprising a steam saturator of the type mentioned at the outset with the features of claim 1.

According to the invention, the device for replenishing the condensate is designed as a condenser and comprises a cooling device for condensing steam supplied by this device.

The solution according to the invention provides for the steam saturator to be expanded to include a condenser operated with a coolant, for example with cooling water. This coolant-operated condenser can preferably be of relatively small dimensions in relation to the volume and size of the steam saturator to which the condenser is assigned. This condenser is preferably sized and arranged so that it only generates the amounts of steam condensate from saturated steam required for make-up. A secondary medium, in particular cooling water, is also required for this. However, this is available in systems of this type anyway and is already monitored with regard to the flow. So there is no effort for additional measurement and control technology.

According to the invention, the steam saturator has at least one condensate return, which is in fluid communication with the lower region of the condenser via at least one connecting line. If condensate is generated in the condenser for the steam saturator as required, it can flow from the condenser to the steam saturator via the connecting line and the condensate return. This condensate return is preferably located in a lower region of the steam saturator. In addition, the steam saturator preferably has a regular condensate outlet in addition to the condensate return at a point that is above the condensate return when viewed in the height direction of the steam saturator, via which condensate can be removed from the steam saturator, for example if the level in the steam saturator is too high.

According to the invention, the steam saturator is further coupled to the condenser via the connecting lines in the manner of communicating tubes, such that when the liquid level of condensate in the steam saturator changes, the liquid level of condensate in the condenser also changes accordingly. As a result of this measure, a drop in the level of condensate in the steam saturator inevitably leads to a drop in the level in the condenser, whereby the process of condensing steam in the condenser is triggered almost automatically when the need for additional condensate has arisen in the steam saturator.

The solution according to the invention therefore takes a different approach than the aforementioned prior art. The evaporated condensate is not supplied to the steam saturator as a circulating liquid, i.e. circulating water, but rather the condensate is only generated in the condenser when necessary, namely when the condensate level in the steam saturator drops, namely by condensing saturated steam, which is produced by the steam saturator Condenser is supplied and then condensed in the condenser by means of the cooling device.

According to a further development of the invention, the arrangement preferably comprises at least one connecting line for saturated steam leading from the steam saturator to the condenser, which is provided in order to convey saturated steam from the steam saturator into the condenser. The steam for the formation of condensate for refilling (topping up) the steam saturator is fed to the condenser via this connecting line, so that an additional steam source is not necessary.

According to a preferred development of the invention, the steam saturator comprises, in addition to the (first) steam outlet for saturated steam, at least one further (second) steam outlet, which is in fluid communication with the condenser via a connecting line. The saturated steam generated in the steam saturator is removed via the mentioned (first) steam outlet and then fed to the corresponding consumption points that require saturated steam. The further (second) steam outlet is connected to the condenser via the connecting line and feeds it with saturated steam, which is required to produce condensate for make-up.

According to a further development of the present invention, the cooling device of the condenser preferably has heat transfer surfaces which are flooded with condensate at normal filling levels in the steam saturator. As long as this normal filling level prevails in the steam saturator, no additional condensate is generated in the condenser. However, if the level in the steam saturator drops, the level in the condenser inevitably also drops and the aforementioned heat transfer surfaces of the cooling device are then partially exposed and condense saturated steam in the condenser, which is supplied to it by the steam saturator. The liquid level of condensate in the steam saturator then increases again.

Attaching the condenser outside the steam saturator therefore has the advantage that steam condensate is not continuously cooled. However, within the scope of the present invention, the condenser can alternatively be arranged both inside and outside of the steam saturator. If it is located within the steam saturator, it does not necessarily require its own housing.

A preferred development of the present invention provides that the condenser has less than half, preferably less than a third, particularly preferably only a fraction, for example only a fifth or only a tenth, of the container size and container volume of the steam saturator. In particular if the condenser is arranged outside the steam saturator and has its own housing, it is a cost advantage if the capacitor is smaller than the steam saturator, preferably significantly smaller than it. The capacitor can, for example, have two flange connections be connected to the actual steam saturator. One of these flange connections is located in the area of a further (second) steam outlet of the steam saturator, from which steam flows from the steam saturator to the condenser via at least one connecting line. The second of these flange connections is in the area of the condensate return, through which condensate generated in the condenser flows to the steam saturator in order to replenish condensate.

For a capacitor located outside the housing of the steam saturator, for example, a cost-effective standard component can be used and, in addition, only a comparatively small heat transfer area is required. The condenser can therefore be made relatively small compared to the size of the steam saturator, since the condenser only has to generate condensate when the liquid level in the steam saturator drops, i.e. the condenser only has to replace the portion of liquid that has evaporated in the steam saturator. For example, an ammonium nitrate plant with a capacity of, for example, 1500 t/day is mentioned here. In such a system, for example, the condenser would have an output of around 20 kW, which would have to be dissipated into the cooling water.

For example, the condenser can be ordered and specified by the user together with the steam saturator, reducing management costs.

According to a preferred development of the present invention, the cooling device of the condenser has a cooling medium inlet and a cooling medium outlet, wherein the cooling medium inlet is preferably fed by an externally supplied cooling medium, which is not the condensate occurring in the steam saturator. At the out DE 2 046 753 A1 Known solution, condensate is removed from the steam saturator as circulating water and used as cooling water in a cooler, where it then heats up and the heated water is mixed with condensate from the cooler and fed back to the steam saturator as circulating water. This is therefore process condensate in conjunction with condensate from the steam saturator, which is used to fill the steam saturator. In the solution according to the invention, however, preferably only a small part of the saturated steam generated in the steam saturator is fed to the cooling device in the condenser and is condensed there using a comparatively small amount of coolant and only when necessary and fed to the steam saturator via the condensate return in order to there Keep fluid levels constant.

According to a preferred development of the present invention, the steam saturator comprises a lying or a standing pressure vessel, within which a steam distributor is arranged in the lower region below the liquid level. In principle, however, the present invention is suitable for both steam saturators Both a standing and a horizontal pressure vessel can be considered. In both variants, a steam distributor is preferably used, which is located below the liquid level in the steam saturator and thus introduces the superheated steam into the liquid (condensate), so that saturated steam is obtained after it emerges from the liquid.

This steam distributor is preferably designed as a pipe which has numerous holes for the steam outlet and which is connected in one end region to the steam inlet of the steam saturator.

A significant further advantage of the solution according to the invention is that an external water source (including the required pipeline on the pipe bridge and an automatic valve) can be saved. The condenser of the steam saturator can be operated with a medium that is already available for the system and is monitored. In addition to savings opportunities when purchasing components, there are also reductions in engineering, assembly and commissioning of the systems. System availability increases, while the effort for operation (e.g. energy for pressure generation and delivery to the steam saturator), maintenance and testing decreases.

The present invention furthermore relates to a method for operating an arrangement comprising a steam saturator and a device for replenishing the liquid evaporated in the steam saturator, in particular for operating an arrangement with the features described above, wherein saturated steam is generated in the steam saturator by superheated steam to the steam saturator (or saturated steam at higher pressure and temperature levels) is supplied, which is introduced via a steam distributor into a liquid volume of condensate in the lower region of the steam saturator, a liquid level of condensate being maintained in the steam saturator by means of the make-up device, which is connected to the Steam saturator is connected, condensate is replenished when the liquid level falls, with steam from the steam saturator being fed to the make-up device according to the invention, this steam being condensed in the make-up device in a cooling device and the make-up device via a connecting line for condensate to the steam saturator is coupled in such a way that when the liquid level in the steam saturator falls, the liquid level in the make-up device also falls, so that steam is automatically condensed in the device and this condensate is fed to the steam saturator.

According to a preferred development of the method, heat transfer surfaces of the cooling device in the make-up device are flooded with steam condensate when the filling level in the steam saturator is normal. In this state, no steam is condensed in the condenser. However, if the filling level in the steam saturator falls below the normal filling level, Heat transfer surfaces of the cooling device in the device for make-up are partially exposed, since the liquid level of the condensate drops there too due to the principle of communicating tubes, as a result of which the steam condenses on these now exposed cooler heat transfer surfaces and steam is condensed in the device. Due to the principle of communicating tubes, the resulting condensate flows into the lower area of the steam saturator, so that the liquid level there rises. This process can take place in an alternating, repeating manner, whereby the liquid in the steam saturator is always replenished by condensate generated in the condenser.

According to a preferred development of the method, condensate arising in the device for replenishing evaporated liquid flows from the device into the steam saturator without pressure and without a separate conveying device. This is advantageous compared to known system concepts in which pressure lines, an external pressure source, automatic valves to control the fill level in the steam saturator and system-internal pumps must be provided for make-up in order to apply the necessary delivery pressure in order to be able to deliver into the pressurized steam saturator.

• Figur 1 eine schematisch vereinfachte Darstellung einer erfindungsgemäßen Anordnung mit Dampfsättiger und Kondensator;
• Figur 2 eine stirnseitige Ansicht der Anordnung mit Dampfsättiger und Kondensator gemäß Figur 1;
• Figur 3 eine vergrößerte schematische Darstellung eines Details aus Figur 1 betreffend den in dem Dampfsättiger angeordneten Dampfverteiler;
• Figur 4 eine Schnittansicht durch den Dampfverteiler von Figur 3.

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

• Figure 1 a schematically simplified representation of an arrangement according to the invention with steam saturator and condenser;
• Figure 2 a front view of the arrangement with steam saturator and condenser Figure 1 ;
• Figure 3 an enlarged schematic representation of a detail Figure 1 regarding the steam distributor arranged in the steam saturator;
• Figure 4 a sectional view through the steam distributor from Figure 3 .

Below we will refer to the Figure 1 Reference is made and based on this an exemplary embodiment variant of the arrangement according to the invention is explained in more detail. The representation according to Figure 1 is schematically very simplified and only those system components are shown that are important in the context of the present invention. The arrangement includes a steam saturator, which is designated overall by the reference number 10. The steam saturator 10 is a pressure vessel, specifically in the exemplary embodiment a horizontal pressure vessel, that is to say the axis of the approximately cylindrical pressure vessel runs essentially horizontally. The one according to the invention Steam saturator 10 is used to generate saturated steam, for which purpose the steam saturator contains a liquid level of condensate up to a certain level, whereby this condensate can in turn be obtained by condensing steam. Superheated steam (or saturated steam at a higher pressure and temperature level) is passed through this condensate, which is then saturated with liquid (water), so that saturated steam is generated. The supplied steam is introduced into the pressure vessel 10 via a steam inlet 12 in the lower region and enters a tubular steam distributor 28, which has numerous holes through which the steam emerges, is introduced into the liquid, is passed through the liquid and out of it as Saturated steam comes out. The saturated steam can be drained away and fed for further use via the steam outlet 11 arranged in the upper area of the pressure vessel.

Furthermore, the steam saturator 10 includes a condensate inlet 13, which is arranged, for example, in an upper region and via which condensate can be supplied to the steam saturator 10. The steam saturator 10 also includes a condensate outlet 14, which can be arranged, for example, in a lateral region of the pressure vessel at a medium height, preferably at a height which corresponds to the intended maximum liquid level of the condensate in the steam saturator 10, so that when this liquid level is exceeded, excess condensate can leave the pressure vessel via the condensate outlet 14.

For example, in a lower middle area, the pressure vessel of the steam saturator 10 has an outlet 16 through which the steam saturator can be emptied and drained. In addition, a filling line 17 is provided in an upper or alternatively in a lower region of the pressure vessel, via which the steam saturator can be filled with water/condensate. In addition, a connection 15 for a safety valve is provided in the upper area of the pressure vessel, so that if there is excess pressure when the safety valve is activated, steam can be released from the pressure vessel via this connection 15. Furthermore, a connection for a ventilation line 18 is preferably provided in an upper area on the pressure vessel. The pressure vessel has, for example, a manhole 19 in a side area, so that the container can be accessed via the manhole for maintenance and cleaning purposes. Finally, the pressure vessel can, for example, have further connections in the upper area, which are provided in reserve, for example in order to connect further units. Connections for measuring devices (e.g. pressure, temperature, level) were not shown for better clarity.

A condensate return 27 is arranged on the pressure vessel in a lower front area, wherein the condensate return 27 can also be attached laterally, for example. This condensate return 27 is connected via a connecting line 25 to a condenser 22, which in this exemplary embodiment is arranged outside the steam saturator and has its own housing. As can be seen from the drawing, the condenser 22 has a significantly smaller size than the steam saturator 10, with a fraction of the size of the steam saturator 10 generally being sufficient. This condenser 22 serves as a device for replenishing the liquid evaporated in the steam saturator through the process of steam saturation. Since superheated steam is introduced into the liquid in the lower region of the steam saturator via the steam distributor 28, part of this liquid evaporates and must therefore be replenished. However, compared to the total volume of liquid in the steam saturator 10, only a relatively small proportion evaporates, so that a small condenser 22 is sufficient for make-up. The condensate generated in the condenser 22 reaches the lower region of the steam saturator 10 via the condensate return 27 and ensures that a sufficient liquid level is always maintained in the steam saturator. This top-up process takes place practically automatically in the arrangement according to the invention and is explained in more detail below.

The steam saturator 10 includes a further (second) steam outlet 20 in the upper area, to which a connecting line 21 is connected, which leads to the condenser 22, so that steam can reach the condenser 22 from the steam saturator 10 via this connecting line 21. In the condenser 22 there is a cooling device 26 with heat exchange surfaces which are in Figure 1 is only shown schematically in simplified form. Normally, these heat exchange surfaces are flooded with condensate, so that no further condensate is generated in the condenser 22. As already mentioned, the steam saturator 10 and the condenser 22 are connected to one another in the lower region via the connecting line 25 and the condensate return 27. Since the condensate return 27 on the steam saturator 10 is at a height at which there is liquid in the steam saturator, the connection via the connecting line 25 works according to the principle of communicating tubes. If the liquid level in the steam saturator 10 drops, it also drops accordingly in the condenser 22. This means that the previously flooded heat exchange surfaces of the cooling device 26 are now partially exposed. A coolant, for example cooling water, is passed through the cooling device 26, for example a coolant loop, which flows in via the cooling water inlet 23 and exits again via the cooling water outlet 24. A coolant that is available in the system can be used here. Since the cooling device 26 is relatively small, A lower volume flow of coolant is sufficient to feed the cooling device 26. If the heat exchange surfaces are now partially exposed due to the drop in the liquid level in the condenser 22, this leads to steam condensing on these cooler heat exchange surfaces, whereby condensate forms and consequently the liquid level in the condenser 22 rises again until the heat exchange surfaces of the cooling device are off again be flooded with condensate. Since the condenser 22 and the steam saturator 10 are connected to one another via the connecting line 25 and the condensate return 27 in the manner of communicating tubes, the liquid level in the steam saturator 10 also rises again due to the formation of condensate in the condenser 22. Condensate is therefore only formed temporarily and fed to the steam saturator, which the steam saturator needs to maintain its liquid level.

Figure 2 shows the steam saturator 10 seen from the front and you can see here the further (second) steam outlet 20 in the upper area for the steam supply from the steam saturator 10 to the condenser and the condensate return 27 in the lower area of the steam saturator for the make-up of condensate from the condenser 22 to the steam saturator . Furthermore, the cooling water loop 26 of the condenser 22 can be seen, which is fed via the cooling water inlet 23. The representation is schematic and the heat exchange surfaces are only indicated.

The Figures 3 and 4 show a detail from the interior of the steam saturator 10 in an enlarged view. Here is in Figure 3 a section of the steam distributor 28 is shown, which is a cylindrical tube with numerous holes 29, which is located in the lower region of the steam saturator, namely below the liquid level. When superheated steam flows into the pipe of the steam distributor 28 via the steam inlet 12, this steam exits the pipe via the holes 29 and flows through the liquid, forming saturated steam, which exits the steam saturator via the steam outlet 11 (see also Figure 1 ) can be dissipated. Figure 4 shows a cross section through the pipe of the steam distributor 28, which is, for example, cylindrical and has numerous holes 29 for the steam outlet.

Reference symbol list

10

Steam saturator

11

Steam outlet

12

Steam inlet

13

Condensate inlet

14

Condensate outlet

15

Connection for safety valve

16

Drain for emptying

17

Filling line

18

vent line

19

manhole

20

another steam outlet

21

Connection line to the capacitor

22

Condenser, device for making up condensate

23

Cooling water inlet, cooling medium inlet

24

Cooling water outlet, cooling medium outlet

25

Connecting line for condensate to the steam saturator

26

Cooling water loop, cooling device

27

Condensate return at the steam saturator

28

Steam distributor

29

holes

Claims (17)

1. An arrangement comprising a steam saturator (10) for generating saturated steam and means for replenishing the liquid vaporized in the steam saturator, the steam saturator (10) comprising a steam inlet (12) through which steam is supplied to the steam saturator, the steam saturator (10) comprising a steam outlet (11) for the saturated steam generated, the steam saturator (10) comprises a condensate return (27), and wherein a liquid level of condensate is maintained in the lower portion of the steam saturator (10) which is in fluid communication with the condensate return (27), the condensate return (27) being in communication with the means for replenishing the vaporized liquid,

   wherein the means for replenishing is formed as a condenser (22) and comprises a cooling device (26) for condensing vapor supplied thereto, wherein the steam saturator (10) has at least one condensate return (27) which is in fluid communication with the lower region of the condenser (22) via at least one connecting line (25),

   characterized in that

   the steam saturator (10) is coupled to the condenser (22) via the connecting line (25) in the manner of communicating tubes, such that when the liquid level of condensate in the steam saturator (10) changes, the liquid level of condensate in the condenser (22) changes accordingly.
2. Arrangement according to claim 1, wherein it comprises at least one connection line (21) for saturated steam leading from the steam saturator (10) to the condenser (22), which is provided to convey saturated steam from the steam saturator (10) into the condenser (22).
3. Arrangement according to one of claims 1 or 2, wherein the steam saturator (10) comprises, in addition to the steam outlet (11) for saturated steam, at least one further steam outlet (20) which is in fluid communication with the condenser (22) via a connecting line (21).
4. Arrangement according to any one of claims 1 to 3, wherein the cooling device (26) of the condenser (22) has heat transfer surfaces which are flooded with condensate at the normal filling level in the steam saturator (10).
5. Arrangement according to claim 4, wherein the heat transfer surfaces of the condenser (22) are positioned in the condenser such that they are partially exposed when the level in the steam saturator (10) is too low.
6. Arrangement according to any one of claims 1 to 5, wherein the condenser (22) is arranged within the housing of the steam saturator (10).
7. Arrangement according to any one of claims 1 to 5, wherein the condenser (22) is arranged outside the housing of the steam saturator (10) and has its own housing, or the condenser (22) is located inside the housing of the steam saturator (10) and optionally does not have its own housing.
8. Arrangement according to one of claims 6 or 7, wherein the condenser (22) has less than half, preferably less than one third, particularly preferably only a fraction of the container size and container volume of the steam saturator (10).
9. Arrangement according to claim 2 or one of claims 3 to 8 referring back to claim 2, wherein the connecting line (21) for saturated steam leading from the steam saturator (10) to the condenser (22) leads into the condenser in an upper region of the condenser (22).
10. Arrangement according to any one of claims 1 to 9, wherein the cooling device (26) of the condenser (22) comprises a cooling medium inlet (23) and a cooling medium outlet (24), wherein the cooling medium inlet (23) is fed by an externally supplied cooling medium which is not the condensate accumulating in the steam saturator.
11. Arrangement according to any one of claims 1 to 10, wherein the steam saturator (10) comprises a horizontal or vertical pressure vessel within which a steam distributor (28) is arranged in the lower region below the liquid level.
12. Arrangement according to claim 11, wherein the steam distributor (28) is formed as a pipe which has numerous holes (29) for the steam outlet and which is connected in its one end region to the steam inlet (12).
13. Method for operating an arrangement comprising a steam saturator and a device for replenishing the liquid evaporated in the steam saturator, in particular for operating an arrangement having the features of one of claims 1 to 12, wherein saturated steam is generated in the steam saturator (10) by supplying superheated steam to the steam saturator, which is introduced via a steam distributor into a liquid volume of condensate standing in the lower region of the steam saturator (10), wherein a liquid level of condensate is maintained in the steam saturator by supplying condensate via the means for replenishing (22), which is in communication with the steam saturator (10), when the liquid level drops, condensate is replenished, characterized in that steam from the steam saturator (10) is fed to the replenishing device (22), this steam is condensed in the replenishing device (22) in a cooling device (26), and the replenishing device (22) is coupled to the steam saturator (10) via a connecting line (25) for condensate in such a manner that when the liquid level in the steam saturator (10) decreases, the liquid level in the device (22) for replenishment also decreases, as a result of which steam is automatically condensed in the device and this condensate is fed to the steam saturator (10).
14. Method according to claim 13, wherein heat transfer surfaces of the cooling device (26) in the device (22) for replenishment are flooded by steam condensate at normal filling level in the steam saturator.
15. Method according to any one of claims 13 or 14, wherein heat transfer surfaces of the cooling device (26) in the device (22) for replenishing are partially exposed at a fill level below the normal fill level in the steam saturator, thereby condensing steam in the device (22).
16. The method of any one of claims 13 to 15, wherein the vapor saturator (10) and the condenser (22) serving as the vaporized liquid make-up device are coupled via the interconnecting conduit (25) in a communicating tube fashion such that as the liquid level of condensate in the vapor saturator (10) changes, the liquid level of condensate in the condenser (22) changes accordingly.
17. A method according to any one of claims 13 to 16, wherein condensate produced in the device (22) for replenishing vaporized liquid flows from the device (22) into the vapor saturator (10) without pressure and without a separate conveying device.

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