WO2019025199A1

WO2019025199A1 - Disinfection facility for liquids

Info

Publication number: WO2019025199A1
Application number: PCT/EP2018/069608
Authority: WO
Inventors: Markus Weber; Peter Maier; Maximilian Blomeier
Original assignee: Markus Weber; Peter Maier; Maximilian Blomeier
Priority date: 2017-07-31
Filing date: 2018-07-19
Publication date: 2019-02-07
Also published as: DE102017117324A1

Abstract

The invention relates to a disinfection facility (1) for fluids to be disinfected, comprising: a substantially cylindrical housing body (10) with an inlet (12) and an outlet (13), the cylindrical housing body (10) having an annular reaction chamber (14) on the inner side, surrounding a cylindrical inner space (15), and an LED-based UV-light source (30) for irradiating the fluid to be disinfected, which flows through the annular reaction chamber (14), the cylindrical housing body (10) i) consisting of a UV-transparent glass and having an inwardly oriented mirror coating (17) on the outer wall (16) thereof, or ii) consisting of a material selected from the group containing glass, plastic and/or metal and having a UV-light-reflecting coating (17a) on the inner wall (16a) thereof, and the LED-based UV-light source (30) being arranged in a coolable manner iii) in the cylindrical inner space (15), or iv) on an outer wall (15a) of the cylindrical inner space (15).

Description

Disinfection plant for liquids

The present invention relates to a disinfecting system for fluids to be disinfected and to a method for disinfecting fluids.

The germicidal, disinfecting effect of UV light for germ killing is known and is often used in water treatment. For example, UV lamps have been used for many decades for the disinfection of drinking water and wastewater, for the disinfection of work areas in biological laboratories and in air conditioning systems. With appropriate dose and wavelength UV light is very well suited to deactivate microorganisms such as spores, fungi, bacteria, parasites, algae, etc. Disinfecting plants of this type can be used for liquids, such as water, and gases, such as indoor air.

Unlike chemical water disinfection processes, UV disinfection relies on a physical process. When bacteria, viruses, etc. are irradiated with the germicidal wavelength of UV radiation, they lose their ability to reproduce and become infected. The microorganisms are thus deactivated by photooxidation of their DNA. More than 99.9% of all pathogens can be rendered harmless in fractions of a second in this way.

The high-energy, entertaining UV radiation has mainly a wavelength of 200 to 280 nm, preferably from 265 to 280 nm. It falls into the so-called short-wave UV-C range and has a strong germicidal effect. However, it has recently been shown that even radiation with a wavelength of up to 405 nm is sufficient to achieve the germicidal effect.

UV disinfection has many advantages and has been proven for a long time. For example, housing bodies are used with an inlet and an outlet, through which the liquid to be disinfected flows and in Their interior has a light source in the form of a mercury vapor lamp that emits UV light.

However, such UV lamps are not suitable for so-called point-of-use applications and temporary operation. In addition to the fact that mercury is harmful when released, the full radiant power is released only after a warm-up period of several minutes.

Object of the present invention is therefore to provide a comparison with the prior art improved disinfection system.

According to the invention the object is achieved by a disinfection system which has a substantially cylindrical housing body with an inlet and an outlet, wherein the cylindrical housing body inside a ring-shaped reaction space surrounding a cylindrical interior, and an LED-based UV light source for irradiation of the annular reaction space flowing through to be disinfected fluid, wherein the cylindrical housing body

i) consists of UV-transparent glass and on its outer wall an inwardly directed mirror coating, or

ii) consists of a material selected from the group of glass, plastic and / or metal and on its inner wall has a UV-reflective coating, and

the LED based UV light source

iii) in the cylindrical interior, or

iv) is arranged coolably on an outer wall of the cylindrical interior.

One of the decisive factors for the invention is that the radiation emitted by the LED-based UV light source can not escape and thus the light energy required for the disinfection of the fluids is optimally utilized.

According to the invention this is achieved in that the cylindrical housing body according to a first embodiment of UV-transparent glass and on its outer wall has an inwardly directed reflection, which reflects the light emitted from the LED-based UV light source radiation. Characterized in that the mirror coating on the outer wall of the cylindrical housing body is arranged, a contamination or abrasion of the mirror coating is advantageously excluded by possibly contained in the fluid dirt particles. For the purposes of the present invention, the term UV-transparent glass is understood to mean a vitreous material which is permeable to UV radiation in the wavelength range from 200 to 500 nm. The UV-transparent glass preferably consists of a material selected from the group comprising quartz glass, borosilicate glass, the term UV-transparent glass also including UV-permeable plastics, such as, for example, polyethylene terephthalate (PET) and / or polymethyl methacrylate (PMMA) ) within the meaning of the present invention.

The mirror coating is preferably a reflective coating based on aluminum, which is applied to the outer wall of the cylindrical housing body. Various coating methods are known in principle to the person skilled in the art. In principle, other materials for the reflective coating, such as silver, can be used. According to a second embodiment variant according to the invention, the cylindrical housing body consists of a material selected from the group consisting of silicon-based glass, plastic and / or metal and has on its inner wall a UV-reflecting coating which is that of the LED-based UV light source reflected radiation emitted.

The UV-reflective coating is preferably made of a material selected from the group consisting of high purity, optical PTFE, expanded PTFE (ePTFE), barium sulfate or any other UV-reflective material available.

The particularly advantageous properties of polytetrafluoroethylene (PTFE), such as an extremely low surface tension and high resistance to acids, bases and UV light, have long been known. Furthermore, PTFE is physiologically harmless. Surprisingly, it has now been shown that high-purity, optical PTFE and ePTFE, in addition to the known properties, for light in the wavelength range of 200 to 500 nm shows a high reflection. The UV-light-reflecting coating preferably has a layer thickness of at least 250 μm, more preferably of 500 μm and very particularly preferably of 1000 μm.

Preferred metals are selected from the group comprising aluminum and / or stainless steel, suitable alloys also being conceivable.

In principle, the housing body can be made from almost any common plastic. However, particularly preferred plastics are selected from the group comprising polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), polyvinyl chloride (PVC) and / or polytetrafluoroethylene (PTFE).

Furthermore, it is crucial for the present invention that the LED-based UV light source can be cooled by the arrangement in the cylindrical interior or on an outer wall of the cylindrical interior, so that the heat generated in the process can be dissipated.

For the purposes of the present invention, the term "LED-based light source" is understood to mean a composite of a multiplicity of light-emitting diodes which are arranged on a carrier strip.

The light-emitting diodes can emit monochromatic UV light in the wavelength range from 200 to 500 nm. The specific wavelength used depends on the planned use of the disinfection system.

The LED technology offers considerable advantages, especially compared to conventional mercury radiating technology. The advantages are in particular: a clearly defined wavelength without disturbing secondary peaks,

a gentle procedure,

selective conversion and therefore no interfering side reactions, safe low-voltage technology,

long life and easy disposal of the light-emitting diodes, Pollutant removal without the addition of aggressive chemicals,

the UV radiation of the LED is available immediately after switching on, previous radiators need a warm-up time of 10 to 20 minutes,

during switching operations, the LEDs have no aging or reduction of life, with previous known from the prior art emitters lose up to 2 hours of life per switching operation and are not suitable due to the warm-up time for so-called "point of use applications" or discontinuous processes , LED spotlight already,

The LED light sources have a defined narrow wavelength range, which is provided depending on the purpose and customer request, through the use of LED different geometries of the disinfection system can be realized,

In addition, LEDs are mechanically robust.

In a particularly advantageous embodiment, the flow-through housing body has at least one, more preferably a plurality of cross-sectional changes. As a result, on the one hand the fluid flowing through the cylindrical housing body is fluidized, on the other hand the UV radiation is reflected in different directions and thus scattered.

The cross-sectional changes may be formed for example by depressions on the outside of the cylindrical housing body, which cause corresponding bulges on the inside. Also, constrictions or similar cross-sectional changes are conceivable. It may be a single cross-sectional change or a variety of cross-sectional changes.

According to a further advantageous embodiment variant, the disinfection system further comprises a mixing valve arranged at the inlet, via which a hot and cold water inlet can be connected. Thus, in particular in so-called point-of-use applications, almost germ-free water in the desired temperature, which is usually 5-75 ° C, available. In one embodiment variant, the inlet is arranged at a first end and the outlet is arranged at a second end of the cylindrical housing body, wherein the inlet can be arranged on the circumference as desired. For example, the inlet is arranged such that the inlet and thus the flow direction of the fluid are oriented in the direction of a body center of the cylindrical housing body.

According to a preferred embodiment variant, the inlet is arranged tangentially, so that the fluid to be disinfected flows helically through the annular reaction space, from the inlet in the direction of the outlet.

In a further advantageous embodiment, the disinfection system further comprises a flow-through channel arranged in the cylindrical interior for a cooling fluid, wherein the LED-based UV light source is preferably arranged on an outer wall of the flow-through channel. This makes the LED-based UV light source coolable.

Thus, in one embodiment, the inlet for the fluid can be fluidically connected in the housing body with an outlet of the flow-through channel, so that the disinfection system forms an open cooling circuit. The disinfectant system supplied to be disinfected fluid is thus initially used as a cooling fluid before it is then supplied to the disinfection.

Alternatively, the flow-through channel is connected to a closed cooling circuit, which cools the LED-based UV light source back. For this purpose, the cooling circuit preferably has a cooling unit that keeps the cooling fluid at a desired temperature.

The channel is preferably made of a metal, such as aluminum or stainless steel.

In another preferred embodiment variant, the inlet and the outlet for the fluid to be disinfected are arranged in the region of a first end of the cylindrical housing body, the cylindrical interior preferably extending in the form of a channel coaxially inside the cylindrical housing body, the channel communicating with the housing Inlet for the fluid to be disinfected fluidly connected and in the region of a second end of the cylindrical Housing body has an opening. The LED-based UV light source is then placed on the outer wall of the channel. The fluid to be disinfected through the channel cools the back of the LED-based UV light source. At the opposite end, the fluid flows out through the opening and into the annular reaction space through which it flows in the direction of the outlet. The radiation emitted and / or reflected by the LED-based UV light source strikes the fluid and disinfects it.

In a particularly advantageous development, the opening is helically formed, so that the fluid to be disinfected flows through the annular reaction space in the form of a helix in the direction of the outlet.

The outer wall of the channel can furthermore preferably be provided with a protective element. For example, the outer wall of the channel may be covered with a plastic layer in which the LED-based UV light source is embedded.

For better mechanical stability or as scratch protection, the cylindrical housing body produced from a silicon-based glass can furthermore be provided with a protective layer, for example made of a plastic.

Deviating from the geometric design of the cylindrical housing body and other shapes are conceivable, for. As square, rectangular and any other technically manufacturable geometry. Also, the housing body may be formed in the form of a Pianarreaktors.

According to a further aspect, the present invention also relates to a method for disinfecting fluids, wherein in a first step, a fluid to be disinfected, preferably to be disinfected water, is introduced into the inventive disinfection system and the fluid in a further step by means of UV radiation is disinfected so that a disinfected fluid is obtained.

The present invention will be explained in more detail below with reference to exemplary embodiments. These embodiments are to be understood as illustrative and not restrictive and are intended to enable those skilled in the art to To carry out invention. It should be noted that the technical features mentioned in the exemplary embodiments, in particular technical means, individually and also in combination with one another can be used by the person skilled in the art for the further development of the objects according to the invention. Show it :

1 is a greatly simplified schematic representation of a disinfection system according to the invention in longitudinal section, Figure 2 shows an enlarged section of a region A of Figure 1,

3 shows a second embodiment of the disinfection system according to the invention in longitudinal section with an open cooling system, FIG. 4 shows a third variant of the disinfection system according to the invention in longitudinal section with a closed cooling system,

Figure 5 shows a fourth embodiment of the disinfection system according to the invention in longitudinal section, and

Figure 6 shows a fifth embodiment of the disinfection system according to the invention in longitudinal section.

FIG. 1 shows a greatly simplified schematic illustration of a variant of the inventive disinfection system 1 for fluids to be disinfected in longitudinal section, comprising a substantially cylindrically shaped housing body 10 made of a UV-transparent glass 11 (FIG. 2) with an inlet 12 and an outlet 13 1, the inlet 12 is disposed at a first end of the cylindrical housing body 10 and the outlet 13 at a second end opposite the first end.

In principle, the inlet 12 can be arbitrarily arranged on the circumference, but in the present embodiment it is arranged such that the inlet 12 and thus the flow direction of the fluid are oriented in the direction of a body center of the cylindrical housing body 10. In an alternative embodiment, the inlet 12 can also be arranged tangentially, so that the fluid to be disinfected helically an annular reaction space 14, from the inlet 12 in the direction of outlet 13 can flow through.

Within the housing body 10, the annular reaction space 14 surrounds a cylindrical interior 15, on whose outer wall 15a an LED-based UV light source 30 (not shown) is arranged. The LED-based UV light source 30 is composed of a plurality of light emitting diodes 31 (not shown) distributed over the entire surface of the outer wall 15 a of the inner space 15.

In a particularly preferred embodiment variant, the interior space 15 with the light-emitting diodes 31 arranged on the outer wall 15a and further electrical components, such as electrical lines, can be formed as a separate unit, which can be removed from the housing body 10 and thus also exchanged.

Furthermore, the housing body 10 has on its outer wall 16 an inwardly directed aluminum-based mirror coating 17, for example in the form of a reflective coating (see FIG. 2). As a result of the mirror coating 17, the UV light emitted by the LED-based UV light source 30, which is shown by way of example in FIG. 2 by means of a beam path 40, is reflected back into the annular reaction space 14 after passing through the UV-transparent glass 11. The fluid to be disinfected, for example water to be disinfected, flows through the inlet 12 into the housing body 10 or into the annular reaction space 14, where it is irradiated with UV light. The specific wavelength of the emitted UV light is preferably in a wavelength range of 200 to 500 nm, more preferably in the wavelength range of 265-280 nm or 400-410 nm.

FIG. 3 shows a longitudinal section of a second embodiment variant of the disinfection system 1 according to the invention, which further comprises an open cooling system 2 and a mixing valve 50 arranged at the inlet 12. The housing body 10 is formed from two cylindrical bodies which form an annular reaction space 14 and an inner space 15 separated therefrom by a wall 15b. In contrast to the first embodiment variant (FIGS. 1 and 2), the cylindrical housing body 10 is provided on an inner wall 16a with a UV-light-reflecting coating 17a, for example comprising ePTFE. Furthermore, the interior space 15 furthermore has a throughflowable cylindrical channel 20 for a cooling fluid, which comprises on its outer wall 21 the LED-based light source 30 in the form of a plurality of light-emitting diodes 31. The light-emitting diodes 31 emit UV radiation which radiates through the UV light-transparent interior wall 15a into the annular reaction space 14 and disinfects the fluid flowing through the annular reaction space 14.

The mixing valve 50 arranged at the inlet 12 has in each case a connection for cold and hot water 51, 52 and can be at a corresponding extraction point, as a so-called. Point-of-use application can be used, for example, to disinfect tap water immediately prior to removal.

As shown in FIG. 3, the cold water inlet 51 is first passed through the channel 20. Because the light-emitting diodes 31 of the LED-based light source 30 are arranged on the outer wall 21 of the channel 20, they are cooled by the fluid flowing through the channel 20, in particular tap water. Figure 4 shows a third embodiment of the disinfection system 1 according to the invention in longitudinal section, which further comprises a closed cooling system 3 and arranged at the inlet 12 mixing valve 50 having a connection for cold and hot water 51, 52 comprises. In contrast to the in Fig. 3, the cylindrical housing body 10 has on its UV light-transparent outer wall 16 an inwardly directed aluminum-based mirror coating 17, which reflects the light emitted by the light-emitting diodes 31. Furthermore, the cylindrical channel 20 arranged in the interior 15 is connected to a closed cooling system 3, which cools the light-emitting diodes 31 at the rear. For this purpose, the cooling system 3 preferably has a cooling unit 4, that the cooling fluid temperature corresponding to a desired temperature.

A further embodiment variant of the disinfection system 1 according to the invention is shown in FIG.

In the case of the cylindrical housing body 10 shown in FIG. 5, the inlet 12 and the outlet 13 for the fluid to be disinfected are arranged in the region of a first end of the cylindrical housing body 10. In contrast to the preceding exemplary embodiments, the cylindrical housing body 10 has a plurality of cross-sectional changes 18, which lead to bulges 19 on the inside. These can have virtually any shape, it is essential that they lead in the annular reaction space 14 to a turbulence of the fluid and to a scattering of the emitted UV light by reflection.

On its UV light-transparent outer wall, the housing body 10, an aluminum-based mirror coating 17, which reflects the UV light.

As in the embodiments previously shown, the inner space 15 in the form of a cylindrical channel 20 extends coaxially within the cylindrical housing body 10, so that an annular reaction space 14 is formed.

The light-emitting diodes 31 are arranged on the outer wall 15 a of the channel 20, so that the fluid to be disinfected through the channel 20 cools the rear side of the diodes 31.

The fluid to be disinfected is introduced through the cylindrical channel 20 into the disinfection system 1. At the end arranged opposite the inlet 12, the channel 20 has an opening 22, via which the fluid flowing through the channel 20 flows into the annular reaction space 14 and flows through in the direction of the outlet 13. The UV radiation emitted by the LED-based UV light source 30 strikes the fluid and disinfects it.

In a particularly advantageous embodiment, the opening 22 is helical, so that the fluid to be disinfected flows through the annular reaction space 14 helically in the direction of the outlet 13. FIG. 6 shows a fifth embodiment variant of the disinfection system 1 according to the invention in longitudinal section. In contrast to the embodiment variant shown in FIG. 5, the outer wall 15a of the channel 20 is provided with a protective element 23, for example in the form of a plastic layer, in which the light-emitting diodes 31 are embedded.

LIST OF REFERENCE NUMBERS

1 disinfection system

2 open cooling circuit

3 closed cooling circuit

4 refrigeration unit

10 cylindrical housing body

11 UV-transparent glass

12 inlet

13 outlet

14 annular reaction space

15 interior

15a outer wall of the interior

15b wall of the interior

16 outer wall of the housing body

16a inner wall of the housing body

17 mirroring

17a UV-reflective coating

18 cross-sectional change

19 bulging

20 cylindrical channel

21 outer wall of the canal

22 opening

23 protective element

30 LED-based UV light source

31 light-emitting diodes

40 beam path

50 mixing valve

51 cold water

52 hot water

Claims

claims

1. Disinfection plant (1) for fluids to be disinfected, comprising:

a substantially cylindrical housing body (10) having an inlet (12) and an outlet (13), the cylindrical housing body (10) having on the inside an annular reaction space (14) surrounding a cylindrical interior (15) and an LED-based one UV light source (30) for irradiating the annular reaction space (14) flowing through to be disinfected fluid, wherein the cylindrical housing body (10)

i) consists of a UV-transparent glass and on its outer wall (16) an inwardly directed mirror coating (17), or ii) consists of a material selected from the group glass, plastic and / or metal and on its inner wall (16a) a UV-light reflective coating (17a),

and wherein the LED-based UV light source (30)

iii) in the cylindrical interior (15), or

iv) is arranged to be cooled on an outer wall (15a) of the cylindrical inner space (15).

2. Disinfection plant (1) according to claim 1, wherein the cylindrical housing body (10) has at least one, preferably a plurality of cross-sectional changes (18).

3. disinfection system (1) according to claim 1 or 2, further comprising a at the inlet (12) arranged mixing valve (50).

4. disinfection system (1) according to any one of the preceding claims, wherein the inlet (12) at a first end and the outlet (13) at a second end of the cylindrical housing body (10) is arranged.

5. Disinfection plant (1) according to claim 4, wherein the inlet (12) is arranged tangentially, so that the fluid to be disinfected flows through the annular reaction space (14) helically.

6. disinfection system (1) according to one of the preceding claims, further comprising a in the cylindrical interior (15) arranged through-flow channel (20) for a cooling fluid.

7. disinfection system (1) according to claim 6, wherein the LED-based UV light source (30) on an outer wall (21) of the flow-through channel

(20) is arranged so that the LED-based UV light source (30) is cooled by the cooling fluid.

8. disinfection system (1) according to claim 6 or 7, wherein the inlet (12) with an outlet (13) of the flow-through channel (20) is fluidly connected and forms an open cooling circuit (2).

9. disinfection system (1) according to claim 6 or 7, wherein the flow-through channel (20) to a closed cooling circuit (3) is connected.

10. Disinfection system (1) according to one of the preceding claims 1 to 3, wherein the inlet (12) and the outlet (13) in the region of a first end of the cylindrical housing body (10) are arranged.

11. The disinfection system (1) according to claim 10, wherein the cylindrical interior (15) extends in the form of a channel (20) coaxially within the cylindrical housing body (10), wherein the channel (20) is fluidically connected to the inlet (12) and in the region of a second end of the cylindrical housing body (10) has an opening (22).

12. Disinfection system (1) according to claim 11, wherein the opening (22) is helical, so that the fluid to be disinfected flows through the annular reaction space (14) helically in the direction of the outlet (13).

13. disinfection system (1) according to claim 11 or 12, wherein the outer wall

(21) of the channel (20) is provided with a protective element (23).

14. disinfection system (1) according to any one of the preceding claims 1 to 13, wherein the cylindrical housing body (10) is provided on the outside with a protective layer.

15. A method of disinfecting fluids comprising the steps of: i) providing a disinfection system (1) according to one of the claims

1 to 14,

ii) introducing the fluid to be disinfected, and

iii) disinfecting the fluid.