DEVICE FOR DISINFECTING A FLUID

Abstract

A device (20) for disinfecting a fluid, in particular water, has a reactor housing (15) with an inlet (19) for ingress and an outlet (9) for discharge of a fluid to be disinfected, wherein a reactor chamber (16) is formed in the reactor housing (15). The fluid to be disinfected flows through the reactor chamber (16) from the inlet (19) to the outlet (9) along a flow path (18). A UV irradiation device (21) with a plurality of UV LEDs (11) is provided, wherein the UV LEDs (11) are disposed on an elongated support element (7) and the support element (7) is configured to extend at least partially into the reactor housing (15) so that by means of the UV LEDs (11), UV light for disinfecting the fluid can irradiate the flow path in the reactor chamber. The support element (7) is releasably and exchangeably mounted in the reactor housing (15) and has a coolant passageway (5, 17) which extends through the support element (7) and through which a coolant can flow in order to cool the UV LEDs (11).

Claims

1. A device for disinfecting a fluid, in particular water, having: a reactor housing with an inlet for ingress and an outlet for discharge of a fluid to be disinfected; a reactor chamber which is formed in the reactor housing and is configured to receive the fluid to be disinfected so that the fluid flows through the reactor chamber along a flow path from the inlet to the outlet; a UV irradiation device with a plurality of UV LEDs; and an elongated support element on which the UV LEDs are disposed and which is configured to extend at least partially into the reactor housing so that by means of the UV LEDs, UV light can be emitted into the reactor chamber along the flow path in order to disinfect the fluid; wherein the support element is releasably and exchangeably mounted in the reactor housing and has a coolant passageway which extends through the support element and through which a coolant can flow in order to cool the UV LEDs.

2. The device as claimed in claim 1, wherein at least a portion of the support element is formed by a thermally conductive material, so that heat generated from the operation of the UV LEDs can be transmitted to a coolant which flows through the coolant passageway.

3. The device as claimed in claim 1, wherein the support element is mounted in the reactor housing in a manner such that it extends at least partially inside of the reactor housing at a distance from a reactor housing wall so that UV light from the UV LEDs can be emitted in the direction of the reactor housing wall.

4. The device as claimed in claim 3, wherein the support element extends along a central longitudinal axis of the reactor chamber.

5. The device as claimed in claim 1, wherein the support element extends in a longitudinal direction through the entire reactor housing.

6. The device as claimed in claim 5, wherein the support element is formed rod-shaped.

7. The device as claimed in claim 1, wherein the coolant passageway extends from a coolant inlet to a coolant outlet which are both disposed at the same end of the support element.

8. The device as claimed in claim 7, wherein the coolant passageway comprises a first section which extends from the coolant inlet and a second section which extends to the coolant outlet, wherein at least a portion of the first section runs inside the second section.

9. The device as claimed in claim 1, wherein having a quartz glass tube which is configured to surround the support element in order to prevent direct contact of a fluid to be disinfected with the UV LEDs in the reactor chamber.

10. The device as claimed in claim 1, wherein the reactor housing is configured as a flow tube, and the inlet is disposed at a first end of the flow tube and the outlet is disposed at an opposite second end of the flow tube.

11. The device as claimed in claim 1, wherein at least one of the inlet and the outlet is disposed laterally on the reactor housing so that a fluid to be disinfected flows through the reactor chamber in a manner such that at least a portion of the flow path passes around the support element in a spiral shape.

12. The device as claimed in claim 11, wherein both the inlet as well as the outlet are disposed laterally on the reactor housing in a manner such that a fluid to be disinfected flows into the reactor chamber in a direction which is at least partially tangential, or the other of the inlet and the outlet runs along a central longitudinal axis of the reactor chamber.

13. The device as claimed in claim 11, wherein the inlet and/or the outlet is/are formed in a corresponding connection piece which has a continuously varying cross sectional surface along the direction of flow.

14. The device as claimed in claim 1, wherein at least a portion of a surface of the reactor housing bordering the reactor chamber is formed from a material which diffusely reflects UV light.

15. The device as claimed in claim 1, wherein having at least one UV sensor for detecting a radiation intensity for the UV light emitted by the UV LEDs as well as an analysis unit which is configured to control the radiation intensity as a function of a signal from the at least one UV sensor.

Description

DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0025] The invention will now be described in more detail with reference to the drawings. In the drawings:

[0026] FIG. 1 shows a side view of a device for disinfecting a fluid in accordance with a first exemplary embodiment;

[0027] FIG. 2 shows a further side view of the device of FIG. 1;

[0028] FIG. 3 shows a sectional view of the device of FIG. 1 along the longitudinal axis;

[0029] FIG. 4 shows a sectional view of the device of FIG. 1 in the transverse direction;

[0030] FIG. 5 shows an enlarged section of FIG. 3;

[0031] FIG. 6 shows a side view of the device of FIG. 1 with a partially withdrawn light source;

[0032] FIG. 7 shows a rod-shaped light source;

[0033] FIG. 8 shows a side view of a device for disinfecting a fluid in accordance with a second exemplary embodiment; and

[0034] FIG. 9 shows a sectional view of the device of FIG. 8 along the longitudinal axis.

[0035] A first exemplary embodiment of a device 20 for disinfecting a fluid, in particular water, will be described below with reference to FIGS. 1 to 7.

[0036] The device 20, which is also described as a reactor, is configured as a flow tube with a tubular reactor housing 15. A fluid to be disinfected, such as water, is introduced via an inlet 19 into a reactor chamber 16 formed by the reactor housing 15 and leaves it via the outlet 9 following successful disinfection. The function of the inlet and outlet may also be interchanged. The device 20 may be operated horizontally as well as vertically. As an example, the flow tube may have a length of 30 cm to 100 cm, preferably 50 cm to 60 cm, and a diameter of 5 cm to 10 cm. In particular, it may be provided for installation in a water supply system. In the exemplary embodiment shown here, the connections for the inlet 19 and the outlet 9 are disposed in corresponding end pieces which are connected via screw flanges 10, 13 to the tubular portion of the reactor housing 15 which is formed by a wall 14.

[0037] Because of the lateral arrangement of the inlet 19 and outlet 9, the water is introduced into the reactor chamber 16 in a tangential direction (see section in FIG. 4), whereupon a spiral-shaped flow, i.e. flow path 18 (see arrow in FIG. 3) is produced. The spiral-shaped (helical) flow can form not only because of the arrangement of the inlet 19 and outlet 9, in particular also because the cross section of the reactor chamber 16 is preferably substantially circular. In addition, fluid guide elements (not shown) may be provided in the reactor chamber 16 in order to optimise the hydraulic system and with this to extend the residence time for the fluid to be disinfected in the reactor 20, in order to optimize the use of the UV illumination for disinfection.

[0038] The UV light is produced by means of a UV light source 21 (see FIG. 6), which is releasably mounted in the reactor housing 15, i.e. it can be exchanged. UV LEDs 11 are provided on appropriate support modules 12 which are disposed on a rod-shaped cooling element 7. As can be seen in FIG. 4, in this exemplary embodiment, three support modules 12 are distributed uniformly around the circumference of the cooling element 7. They respectively extend along the length of the cooling element 7 (see FIG. 6). In order to protect the LEDs 11 and also to act as an inner border of the reactor chamber 16, a quartz glass tube 6 is provided which surrounds the UV light source 21.

[0039] The number and power as well as the position of the LEDs 11 can be varied and can therefore be adjusted to the required cleaning and disinfecting power. The LEDs 11 can produce UV light of different wavelengths in the range from 240 to approximately 400 nm and can therefore be tailored to disinfect specific microorganisms. In addition, the LEDs 11 can be dimmed. By irradiating at different wavelengths, the disinfecting power of various microorganisms which are present in water at the same time can be increased. Preferably, the UV light source 21 is flexible in construction, so that it may, for example, be extendable in a modular manner. The rod-shaped UV light source 21 may be supplied with current via a direct connection, or it may be supplied by induction.

[0040] In this exemplary embodiment, the UV light source 21, i.e. in particular the cooling element 7, extends over the entire length of the reactor chamber 16 along its central longitudinal axis. The UV LEDs 11 are likewise disposed substantially along the entire length, so that the flow path 18 is completely irradiated. The UV light is emitted from the inner UV light source 21 radially outwards in the direction of the housing wall 14. This is preferably coated with a suitable material, for example PTFE, on its inner surface, in order to diffusely reflect the UV light so that after reflection, it can act on the water again.

[0041] Screw flanges 2 are provided at both ends of the cooling element 7 so that the cooling element can be secured by tightening the screw flange 2 at both sides of the reactor housing 15. It should be understood that other suitable mechanisms for fastening may be envisaged. By loosening the screw flange 2, the cooling element 7 with the UV LEDs 11 disposed thereon can be removed from the reactor housing 15. This enables the UV light source 21 to be changed easily without dismantling the reactor 20 further. The accessibility of the cooling element 7 from both sides provides for more freedom when installing the reactor 20, for example in a water supply system. Seals 8 are provided in order to seal the reactor chamber 16 at the corresponding openings through which the UV light source 21 is introduced into the reactor housing 15 or removed therefrom. Changing the light source is illustrated in FIG. 6. In the side view, the reactor housing 15 is shown with the cooling element 7 partially withdrawn out of the top.

[0042] The LEDs 11, in particular the rear side thereof, heats up during operation so that, in particular in order to provide a sufficiently high radiant power, appropriate cooling of the LEDs 11 is necessary. Because of the internal position of the light source 21 in the reactor housing 15, no air cooling, for example via appropriate cooling ribs, is possible or at least not sufficient. The cooling element 7 therefore has a coolant passageway 5, 17 via which a liquid coolant can be fed through the cooling element 7. Water cooling in particular can be provided in this manner. The coolant may be the water to be disinfected itself, which is fed in an appropriate circuit not only through the reactor chamber 16, but also through the coolant passageway 5, 17 before or after that. Likewise, however, an external cooling circuit with another coolant, which may also be water, may be provided.

[0043] A coolant inlet 3 and a coolant outlet 4 are provided in a common connection piece 1 at one end of the cooling element 7, which facilitates connection of a cooling circuit and therefore also the exchangeability of the UV light source 21. The coolant may be fed in through the inlet 3 into a first coolant passageway section 5 which is formed by an inboard tube with an open free end, which discharges into a second coolant passageway section 17 which runs in the cooling element 7 close to the rear side of the LEDs 11. After the coolant has flowed through the coolant passageway section 17 substantially along the entire length of the cooling element 7, it can be discharged through the outlet 4. This arrangement also allows air to escape easily from the coolant passageway.

[0044] The provision of water cooling means that a desired radiant power can be obtained so that, for example, an additional filter does not have to be disposed in the reactor 20. At the same time, however, this enables the UV light source 21 to be changed easily. The rod-shaped shape of the support element or cooling element 7 allows the UV LEDs 11 to be distributed in order to produce a homogeneous radiation field in the reactor chamber 16.

[0045] FIGS. 8 and 9 show a second exemplary embodiment of a device for disinfecting a fluid which is substantially identical to the first exemplary embodiment. In this regard, reference should be made to the description above. The second exemplary embodiment differs from the first exemplary embodiment only in the arrangement of the inlet and outlet and therefore in the flow in the reactor chamber 16. While the inlet 19 in the first exemplary embodiment is disposed at the bottom and the outlet 9 is disposed at the top and the fluid to be disinfected flows in and also out in a tangential direction, the inlet 19 in the second exemplary embodiment is at the top and the outlet 9 is at the bottom. It should be understood that in both exemplary embodiments, the inlet 19 and the outlet 9 may also be interchanged. In this manner, the water can flow from the top to the bottom or vice versa, depending on how the reactor 20 is connected up. At the same time, a horizontal arrangement of the entire reactor 20 is possible so that the water flows from left to right or vice versa.

[0046] The fluid to be disinfected flows in a tangential direction through the inlet 19 into the reactor chamber 16. However, the outlet 9 is disposed along the central longitudinal axis, so that the fluid flows straight downwards out of the reactor chamber 16. In order to improve the flow, in particular as regards the helical flow 18, the connection piece for the outlet 9 is rounded and forms a smooth transition. The cross section of the connection piece narrows continuously in the direction away from the reactor housing 15, wherein at the point of connection with the reactor housing 15, it corresponds to the cross section of the reactor housing 15 and at the free end to that of a connecting line, for example.