Condensate drainage system and electrolyzer with a condensate drainage system

Abstract

The invention relates to a condensate discharge device (10; 10a), with a condensate container (12) for receiving a condensate (K), with a first level measuring device (20) for detecting at least a minimum level (F) min ) and a maximum fill level (F max ) of the condensate (K) in the condensate container (12), with a line (26) for draining the condensate (K) from the condensate container (12), wherein a first valve device (28) controllable by the first level measuring device (20; 20a) is arranged in the line (26), with a second level measuring device (24; 24a) for detecting a minimum level (F) u ) of the condensate (K) below the minimum level detectable by the first level measuring device (20; 20a) (F) min ).

Description

Technical area

[0001] The invention relates to a condensate discharge device, in particular as a component of a PEM electrolyzer, which is characterized by a particularly reliable and safe operation over a wide temperature and pressure range of the condensate. State of the art

[0002] From DE 35 45 202 C3, a condensate drainage device is known which pumps the condensate out of a condensate tank. A level switch is also provided for controlling the pumps.

[0003] From DE 10 2009 054 220 B4 it is further known to use electrically and / or pneumatically designed valves in a fluid control unit for the discharge of condensate.

[0004] Most recently, it is known from DE 10 2016 119 386 A1 to provide valves in connection with a motor control system on a condensate tank, which ensure a targeted discharge or supply of the condensate to consumers from the condensate tank. Disclosure of the invention

[0005] The condensate discharge device according to the invention, with the features of claim 1, has the advantage that, particularly in conjunction with a PEM electrolyzer, it enables use over a wide temperature and pressure range of the condensate and operates with exceptional reliability and safety. In particular, for safety reasons, it reliably prevents the complete discharge of condensate from a condensate tank, thereby preventing the escape of gas and thus the formation of an explosive atmosphere in downstream system components, as well as any potential damage to the electrolyzer.

[0006] The invention is based on the idea of ​​using two independently operating valve devices, controllable by different level measuring devices, to ensure that a minimum fill level in the condensate tank is not undershot, so that the condensate tank is always (gas-tight) sealed in the direction of the cathode / anode line supplying the condensate tank, or rather, that no gas can enter via said connection. Furthermore, the condensate discharge device according to the invention makes it possible to implement operating parameters in the condensate tank that cover a wide pressure and / or temperature range. This refers in particular to temperature ranges between 5°C and 95°C of the condensate and condensate pressures between 1 bar and 100 bar (absolute).

[0007] In light of the above explanations, a condensate discharge device according to the invention, comprising the features of claim 1, therefore includes a condensate container for receiving condensate. Furthermore, a first level measuring device is provided for detecting at least a minimum and a maximum level of condensate in the condensate container. The condensate can be discharged from the condensate container by means of a line for draining it, in particular down to a minimum level. A first valve device, controllable by the first level measuring device, is arranged in the line and serves to adjust the level in the condensate container between a minimum and a maximum level of condensate.Furthermore, a second level measuring device is provided for detecting a lowest level of the condensate below the minimum level, as well as a second valve device arranged in series with the first valve device in the line, which can be controlled (safety-oriented) by the second level measuring device.

[0008] Advantageous further developments of the condensate discharge device according to the invention are listed in the dependent claims.

[0009] The discharge of condensate from the condensate container can be achieved with relatively simple valve devices by designing the first and / or second valve device as a 2-way valve to block or release the condensate from the line.

[0010] In order to set a certain minimum pressure or target pressure in the condensate container when draining or discharging the condensate, it is also advantageous if an orifice or throttle is arranged in the line in the direction of flow after the two valve devices.

[0011] Various configurations are conceivable with regard to the design of the first and / or the second valve assembly. In a first preferred embodiment, at least the first valve assembly is designed as a solenoid valve with spring return. Furthermore, at least the second valve assembly can be designed as a pneumatic valve with spring return.

[0012] The condensate tank is designed in particular as a pressure vessel, enabling a pressure range between 1 bar and 100 bar (absolute) and a temperature range between 5°C and 95°C.

[0013] The condensate discharge device described so far is preferably a component of a PEM electrolyzer.

[0014] Furthermore, the invention also includes a PEM electrolyzer with a condensate discharge device designed according to the invention as described above.

[0015] Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments of the invention and from the drawings. Short description of the drawings Fig. 1 and Fig. Figure 2 shows schematic representations of differently designed condensate discharge devices as part of a PEM electrolyzer. Embodiments of the invention

[0016] Identical elements or elements with the same function are provided with the same reference numbers in the figures.

[0017] In the Fig. Figure 1 shows a first condensate drain device 10, shown in a highly simplified form, preferably as part of a PEM (Proton Exchange Membrane) electrolyzer 100. Using the PEM electrolyzer 100, water can be split into its components oxygen and hydrogen by means of a voltage source in a known manner. In this process, condensate K or water is typically produced, as is also known from the prior art. This condensate must be drained by means of the condensate drain device 10 to ensure the functionality or operation of the PEM electrolyzer 100 over a longer period of time.

[0018] The condensate discharge device 10 includes a condensate tank 12 for the condensate K. The condensate tank 12 is connected to a cathode / anode line 101 of the PEM electrolyzer 100 via a feed line 14 to introduce the condensate K into the condensate tank 12. A vent line 16, also connected to the cathode / anode line 101, serves to vent the condensate tank 12 towards the cathode / anode line 101.

[0019] The condensate container 12 is designed as a pressure vessel 18, wherein the condensate K in the condensate container 12 can have a pressure between 1 bar and 100 bar (absolute) and a temperature between 5°C and 95°C.

[0020] The condensate tank 12 also has a first level measuring device 20 for measuring the level of the condensate K in the condensate tank 12. The first level measuring device 20 is located at the condensate discharge device 10 according to the Fig. 1 designed as a level sensor 22 and has at least two switching points, and can also enable continuous measurement of the fill level of the condensate K in the condensate container 12.

[0021] The two switching points that can be detected by means of the first level measuring device 20 include a minimum level F min and a maximum fill level F max of the condensate K in the condensate container 12. The two fill levels F min and F maxcharacterize the normal operation of the condensate discharge device 10 or the PEM electrolyzer 100, i.e., that the level of the condensate K in the condensate container 12 remains between the two fill levels F during operation. min and F max should be located.

[0022] Furthermore, a second level measuring device 24 is located in the area of ​​the condensate container 12, which is used to detect a minimum fill level F u serves this purpose. The lowest fill level is F. u lower or less than the fill level F min , i.e., that at the lowest fill level F u There is less condensate K in the condensate container 12 than at fill level F. min The lowest fill level F uindicates a fill level of the condensate K in the condensate container 12, which must be maintained at a minimum to prevent gases or air from entering the environment and the condensate container 12 in the direction of the PEM electrolyzer 100 or the cathode / anode line 101, which would impair the proper operation of the PEM electrolyzer 100.

[0023] Preferably, a line 26 for draining condensate K from the condensate tank 12 is arranged at the bottom of the condensate tank 12. A first valve assembly 28 and a second valve assembly 30 are arranged in series in the line 26. The first valve assembly 28 is located at the point where the condensate K is discharged from the tank. Fig. In the illustrated embodiment, the first valve assembly 28 is arranged downstream of the second valve assembly 30, viewed in the direction of condensate K flow. The first valve assembly 28 is designed as a solenoid valve 29 with spring return and comprises two switching positions: a first switching position in which condensate K is allowed to flow through line 26, and a second position in which line 26 is blocked for condensate K. The spring return ensures that the second switching position is assumed when the valve is not actuated. The first valve assembly 28 is actuated via the first level measuring device 20 or the level sensor 22 through a control line 32. In the illustrated embodiment, the control line 32 is arranged directly between the first level measuring device 20 and the first valve assembly 28.However, it is also conceivable that the signal from the first level measuring device 20 is fed to a control device not shown, which in turn serves to control the first valve device 28.

[0024] The second valve assembly 30, located between the condensate tank 12 and the first valve assembly 28 in the direction of condensate flow K, is designed as a pneumatic valve 31 with spring return. The second valve assembly 30 is actuated indirectly or directly via the second level measuring device 24. The second valve assembly 30 also has two switching positions: a first switching position in which the discharge of condensate K via line 26 is blocked, and a second switching position for the discharge of condensate K via line 26. The spring return ensures that the first switching position is assumed when the valve is not actuated.

[0025] Finally, in the direction of flow of the condensate K, a flow element 34 in the form of an orifice or throttle is arranged after the first valve assembly 28, which serves to maintain a certain minimum pressure when the condensate K is discharged via the line 26 into the condensate container 12.

[0026] During normal operation of the condensate discharge device 10, the discharge of the condensate K via line 26 is realized by opening the first valve device 28 when the second valve device 30 is open, as soon as the first level measuring device 20 reaches a maximum level F max detected. As a result, the condensate level K in the condensate container 12 drops to the minimum level F. min, whereupon the first level measuring device 20 at least indirectly causes the first valve device 28 to close. However, should this not occur, the lowest level F can be determined by means of the second level measuring device 24. u If this is the case, the second valve device 30 is closed or locked to prevent further discharge of condensate K from the condensate container 12.

[0027] The Fig. The condensate discharge device 10a shown in Figure 2 differs from the condensate discharge device 10 essentially in that its first level measuring device 20a has two level switches 36, 38 for detecting the minimum level F min as well as the maximum fill level F max of the condensate K. The two level switches 36, 38 serve directly to control the first valve assembly 28, which in the illustrated embodiment according to the Fig.2 is arranged between the condensate tank 12 and the second valve assembly 30. Furthermore, the second level measuring device 24a is also designed as a level sensor 40 for controlling the second valve assembly 30.

[0028] The condensate discharge device 10, 10a described so far can be modified or adapted in a variety of ways without deviating from the inventive concept. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 35 45 202 C3

[0002] DE 10 2009 054 220 B4

[0003] DE 10 2016 119 386 A1

[0004]

Claims

[1] Condensate discharge device (10; 10a), with a condensate container (12) for receiving a condensate (K), with a first level measuring device (20) for detecting at least a minimum level (F min ) and a maximum fill level (F max ) of the condensate (K) in the condensate tank (12), with a line (26) for discharging the condensate (K) from the condensate tank (12), wherein a first valve device (28) which can be controlled by the first level measuring device (20; 20a) is arranged in the line (26), with a second level measuring device (24; 24a) for detecting a lowest level (F u ) of the condensate (K) below the minimum fill level (F min), and with a second valve device (30) arranged in series with the first valve device (28) in the line (26) for discharging the condensate (K), which second valve device can be controlled by the second level measuring device (24; 24a). [2] Condensate discharge device according to claim 1, characterized by that the first and / or second valve device (28, 30) is / are designed as a 2-way valve for blocking or releasing the line (26). [3] Condensate discharge device according to claim 1 or 2, characterized by that in the line (26) in the flow direction after the two valve devices (28, 30) a flow element (34) in the form of an orifice or throttle is arranged to influence the pressure prevailing in the condensate container (12) when the condensate (K) is discharged. [4] Condensate discharge device according to one of claims 1 to 3, characterized bythat at least the first valve device (28) is designed as a solenoid valve (29) with spring return. [5] Condensate discharge device according to one of claims 1 to 4, characterized by that at least the second valve device (30) is designed as a pneumatic valve (31) with spring return. [6] Condensate discharge device according to one of claims 1 to 5, characterized by that the condensate tank (12) is designed as a pressure tank (18). [7] Condensate discharge device according to claim 6, characterized by that the pressure vessel (18) is designed for a pressure range between 1 bar and 100 bar and a temperature range between 5° C and 95° C of the condensate (K). [8] Condensate discharge device according to one of claims 1 to 7, characterized by that the condensate discharge device (10) is a component of a PEM electrolyzer (100). [9] PEM electrolyzer (100) with a condensate discharge device (10) designed according to one of claims 1 to 8.

Images