WO2013029716A1

WO2013029716A1 - System for disinfecting or treating a liquid by means of uvc radiation, and radiator module suitable therefor

Info

Publication number: WO2013029716A1
Application number: PCT/EP2012/003013
Authority: WO
Inventors: Alex Voronov; Volker Adam; Burkhard Jung
Original assignee: Heraeus Noblelight Gmbh
Priority date: 2011-08-29
Filing date: 2012-07-18
Publication date: 2013-03-07
Also published as: DE102011111367B4; DE102011111367A1

Abstract

In a known system for disinfecting or treating a liquid by means of UVC radiation, a cylindrical encasing tube made of quartz is arranged in a conduit channel through which the liquid flows and is arranged transversely to the direction of flow, which cylindrical encasing tube receives a UV radiator unit for generating the UVC radiation. In order, proceeding therefrom, to provide a structurally simple system which permits, with high efficiency, the disinfection or treatment of a liquid by means of UVC radiation, according to the invention it is proposed that the radiator unit generates a radially asymmetric radiation profile of the UVC radiation that has an intensity maximum in the direction transverse to the cylindrical axis of the encasing tube and transverse to the direction of flow.

Description

Plant for sterilization or treatment of a liquid by means of UVC radiation and suitable emitter module

description

The invention relates to a plant for the sterilization or treatment of a liquid by means of UVC radiation, with one of the liquid in the flow direction to be flowed duct and a transverse to the flow direction arranged cylindrical sheath tube made of quartz glass, within the same and along the cylinder axis is a UV - Radiator unit for generating the UVC radiation extends

Furthermore, the invention relates to a suitable for use in the system radiator module, comprising a surrounded by a cylindrical tube of quartz glass UV lamp unit for generating UVC radiation. State of the art

For the treatment and disinfection of water, such as bathing and drinking water, but also polluted wastewater from trade and industry, leachate from landfills or liquids that are incurred or needed in medical or technical applications, such as dialysis fluids or sterile ultrapure water, is a UV radiation generally common. As a result, the pathogenic microorganisms (bacteria, viruses, protozoa) contained in the liquid are reduced.

The generation of high-energy UVC radiation is usually carried out by means of mercury vapor lamps. The threshold dose of the applied UV radiation to achieve a germicidal effect is, depending on the requirement for sterility in a range of 100 J / m ² to 1000 J / m ² , wherein the wavelength of the UVC radiation in a range of 200 nm to about 280 nm, and in particular at the emission maximum of mercury vapor lamps is around 254 nm. Roughly, a distinction can be made between degermination plants, in which the mercury vapor lamps are flowed longitudinally by the liquid to be treated and those with transverse inflow. This invention is concerned with a modification of the last named systems. The liquid to be treated may be pumped or passed through an open or closed channel through which the mercury vapor lamp extends transversely to the tube longitudinal axis. In order to prevent direct contact with the liquid, the mercury vapor lamp is surrounded by a cladding tube of UV-transparent material, which is thus transversely flowed by the liquid to be sterilized. In the case of high demands on sterility, such as for drinking water sterilization, and in the case of large flow volumes of the liquid, several radiator units are used. Such a germicidal plant is described for example in DE 26 30 496 A1, wherein the radiator units with their cladding penetrate the duct in a plane one behind the other or in several superposed planes transversely. It is known that flow paths with a lower UV radiation form within the duct, in which organisms have a higher probability of survival. The reason for this can be a comparatively high flow velocity of the liquid or a large distance to the radiator unit. In the case of a transverse flow, these flow paths-also referred to below as "low-irradiation flow paths" -are located above and below the radiator unit or the radiator unit level (in the case of a horizontal arrangement) in order to ensure the required irradiation dose and sterility even in the low-irradiation flow paths For a given liquid throughput, either the radiant power of each individual radiator unit may be higher, or the number of radiator units must be greater than otherwise necessary Both measures lead to increased energy expenditure and over-irradiation of the areas outside of the low-irradiation flow paths and thus to a reduced one Overall efficiency of the plant.

Another way is taken in the known from DE 10 2007 018 670 A1 disinfection system. This is used to disinfect the ballast water of ships before it passes from ballast water tanks through a pumping line in the surrounding seawater. It is proposed to avoid the formation of low-irradiation flow paths by a plurality transversely flowed UV radiator units are installed one behind the other in the pumping line, wherein the cladding tubes are not parallel to each other, but adjacent ducts to a certain angle are rotated by 30 degrees to each other, so that the angle of rotation of the cladding in the flow direction of the medium changes gradually.

However, this construction is expensive, in particular if (as preferred) the cladding tubes run outside the pumping line central axis and result in different lengths of length within the pumping line with each angle of rotation.

Technical Problem The invention has for its object to provide a simple construction system that allows the sterilization or treatment of a liquid by means of UVC radiation with high efficiency.

Furthermore, the invention has for its object to provide a radiator module, which is particularly suitable for use in such a system. General presentation of the invention

With regard to the degerming plant, this object is achieved on the basis of a plant of the type mentioned above in that the emitter unit generates a radially asymmetric radiation profile of the UVC radiation having an intensity maximum in the direction transverse to the cylinder axis of the cladding tube and transverse to the flow direction. The invention aims to reduce or avoid low-radiation flow paths in the duct, by using a radiator unit or multiple radiator units with asymmetric radiation profile.

Conventional radiator units with a cylindrical UV lamp show a rotationally symmetrical radiation profile about its longitudinal axis. This profile generates the same radiation intensity in the direction of low-irradiation flow paths as in all other directions. In contrast, in the case of the invention, a radiation profile is provided which is "radially asymmetrical" about the cylinder axis of the cladding tube, ie non-rotationally symmetrical .This profile has at least one maximum which lies in the direction of a radiation-poor flow path.

The relative position of such low-irradiation flow paths with respect to the transversely directed radiator unit results from fluidic considerations of the specific flow system. This location is usually known or it is predictable or measurable. In horizontally oriented and centrally arranged in the duct channel radiator unit are low-irradiation flow paths usually "below" and "above" of the transversely flowed cladding.

In the case of horizontal orientation, the emitter unit according to the invention thus ideally has a radial radiation profile which has intensity maxima both "below" and "above" the emitter unit cylinder axis. More generally - that is, independent of the orientation of the emitter unit in space - the intensity maximum of the radiation profile extends both transversely to the cylinder axis of the cladding tube (and thus also transversely to the longitudinal axis of the radiation tube).

105 lereinheit) and also transverse to the flow direction of the liquid.

The extension of the intensity maximum "transversely" to said axis and direction means that the straight line characterizing the intensity maximum in the radial cross-sectional profile is at an angle not equal to 0 degrees to the cylinder axis or to the flow direction Said angle is preferably between 60 and 120 degrees and ideally at 90 +/- 110 5 degrees.

As a result of the radially asymmetric radiation profile, the required irradiation dose can also be achieved in the otherwise low-irradiation flow paths, without having to use an overall excessive radiant power. This leads to an irradiation dose better adapted to the specific requirements over the duct channel cross-section, which contributes to a higher overall efficiency of the system.

The invention avoids or reduces the formation of low-irradiation flow paths, without the need for geometrically complex and structurally complex arrangements of multiple radiator units, as in the prior art explained in the introduction.

With regard to the lowest possible energy consumption and a high overall efficiency of the system, it proves to be advantageous if the radially asymmetric radiation profile has an intensity minimum transversely to the direction of the cylinder axis of the cladding tube and in the flow direction.

In addition to the at least one intensity maximum, the radial radiation profile also has at least one intensity minimum. However, this extends in the flow direction 125 and usually perpendicular to the direction of the intensity maximum. Because in the flow direction often results in a relatively low irradiation requirement, for example due to a low flow velocity of the liquid in the impingement of the cladding tube and on the opposite cladding tube side. In the case of several intensity maxima, ideally also a plurality of intensity minima with corresponding orientation are provided. A particularly low energy requirement and a high overall efficiency of the system result if the intensity of the UVC radiation at a wavelength of 254 nm in the maximum at least 50% higher (relative to the minimum value), preferably at least 100% higher than in the minimum ,

In a preferred embodiment of the system according to the invention it is provided that the radiator unit comprises a plurality of elongate UV lamps, which are arranged parallel to one another and in the flow direction one behind the other, and which are surrounded by a common cladding tube.

In this case, two or more elongated UV lamps are arranged within a cladding tube so that their longitudinal axes are parallel to each other. The longitudinal axes of the UV lamps span one lamp plane. The radiation profiles of the individual UV lamps are superimposed and produce in their entirety a radial radiation profile which has a maximum in both directions perpendicular to the lamp plane, and in each case a minimum in the lamp plane. The lateral distance of the UV lamps and their respective power determine the position and the height of the two intensity maxima and the two intensity minima of the total radiation profile.

Preferably, such a radiator unit has exactly three UV lamps, which are arranged parallel to one another and one behind the other in the flow direction.

With more than three UV lamps, a radiation profile results with a particularly pronounced maximum of the radiation intensity, which can lead to overcompensation of the radiation dose in the low-irradiation flow paths.

The formation of irradiation-poor flow paths is influenced by the flow conditions within the duct. Turbulences can counteract the formation of low-irradiation flow paths. On the other hand, turbulences prevent the precise localization and a uniform and predictable expression of any low-irradiation flow paths, which makes the compensation by intensity adjustment of the UVC radiation difficult. Therefore, for the purposes of the invention, a more laminar flow of the liquid to be treated is desired. In this regard, it has proved to be advantageous if the cladding tube has an oval cross-section with mutually opposite two pointed ends and two blunt ends, wherein the cladding tube is arranged within the conduit so that the pointed ends are directed in the direction of the conduit channel. Have longitudinal axis.

The cladding tube has an oval, ideally elliptical cross section. The arrangement in the liquid flow such that the pointed cladding tube ends of the oval extend in the flow direction and in the opposite direction, reduces the formation of turbulence. An oval cladding tube is also particularly well suited as a sheath for radiator units with several, preferably exactly three UV lamps, which are arranged parallel to one another and in the flow direction one behind the other. Because in the flow direction of the liquid to be treated, it offers more space than a round tube and it reduces the formation of undesirable turbulence, such as

already explained above.

In the simplest case, the duct is closed and has an inner wall with a circular cross-section. Typical inner diameters of the cladding tubes are in the range between 20 and 50 mm. The radially asymmetric radiation profile of the UVC radiation is preferably such that at no point on the inner wall of the duct is an excessively high radiation intensity substantially exceeding the nominally required irradiation dose.

The requirements for the degree of disinfection of disinfection plants are different. The threshold dose of the applied UV radiation to achieve a germicidal effect is, depending on the requirement for sterility in a range of 100 J / m ² to 1000 J / m ² , wherein the wavelength of the UVC radiation in a range of about 100 nm 300 nm, and in particular at the emission maximum of mercury vapor lamps is around 254 nm. The degree of sterilization depends on the intensity of the UV radiation. An adaptation of the UV irradiation intensity to the specific conditions is possible through the use of UV lamps with different nominal power, which leads to a specific, nominal irradiation dose depending on the process and plant parameters. The system is then designed to meet the specific nominal irradiation dose at each point in the duct.

As already explained above, an over-irradiation of areas outside of low-irradiation flow paths is often accepted for safety reasons in order to be able to enter the low-irradiation flow paths to ensure even a sufficient dose of radiation. The system of the invention helps to avoid such over-irradiation of the liquid to be treated and thus contributes to a saving of power installation and energy. The maximum radiation power in the region of the intensity maximum is selected, for example, such that a radiation intensity which does not significantly exceed the nominal irradiation dose is achieved on the inner wall of the conduction channel for radiation having a wavelength of 254 nm.

With regard to the radiator module, the above-mentioned technical object is achieved starting from a radiator module of the type mentioned in the present invention that the UV radiator unit is equipped with a plurality of elongated UV lamps, which are arranged parallel to the tubular cylinder axis and each other, and in generate radially asymmetric radiation profile of the UVC radiation having an intensity maximum in the direction transverse to the cylinder axis of the cladding tube.

The radiator module according to the invention generates a radial radiation profile - viewed in the direction of the longitudinal axis of the cladding tube - "radially asymmetric", ie non-rotationally symmetrical .This profile has at least one intensity maximum. As a result of this radially asymmetric radiation profile, the radiator module is suitable for use in the The sterilization unit described above is suitable for arranging the emitter module within a conduit through which the liquid to be treated flows, so that the intensity maximum points in the direction of a low-irradiation flow path The emitter module comprises two or more elongated UV lamps which are within their common The longitudinal axes of the UV lamps span one lamp plane, and the radiation profiles of the individual UV lamps are superimposed and in their entirety produce a radial radiation profile which is present in both n each direction has a maximum perpendicular to the lamp plane, and in the lamp level in each case a minimum. The lateral distance of the UV lamps and their respective power determine the position and the height of the two intensity maxima and the two intensity minima of the total radiation profile.

Preferably, exactly three UV lamps are provided. With more than three UV lamps, a radiation profile results with a particularly pronounced maximum of the radiation intensity, which can lead to overcompensation of the irradiation dose. Amalgam lamps are characterized by a particularly high efficiency. Particularly in view of this, an embodiment of the radiator module is preferred in which the UV lamps are designed as high-performance amalgam lamps.

High-performance amalgam lamps are lamps with a nominal output of at least 200 watts.

Furthermore, it has proven to be advantageous if the cladding tube has an oval cross section with each opposite two pointed ends and two blunt ends.

The cladding tube has an oval, ideally elliptical cross section. The emitter module configured in this way can be arranged in a liquid flow such that the pointed cladding tube ends of the oval extend in the flow direction and in the opposite direction. This reduces turbulence in the flow.

embodiment

The invention will be explained in more detail with reference to embodiments and a drawing. In detail, FIG. 1 shows a sterilization system for water with a radiator module made of cladding tube and

Amalgam lamp with radially asymmetric radiation profile according to the invention in a view in the direction of flow of the water to be treated,

FIG. 2 shows the degerming plant of FIG. 1 in a plan view of the emitter module;

FIG. 3 shows the radiator module of FIG. 1 in a view perpendicular to the flow direction of the water to be treated, together with a diagram of the radiation intensity, and FIG

4 shows a radiator module according to the prior art in a view perpendicular to

Flow direction of the water to be treated together with a diagram of the radiation intensity. The system shown schematically in Figure 1 is used for the sterilization of swimming bath water. It comprises a conduit 1 made of stainless steel with a round cross section, through which the water to be sterilized is pumped and in which a radiator module 2 is arranged perpendicular to the flow direction. The flow direction runs in the view of FIG. right to the sheet direction and is symbolized in Figures 2 to 4 with directional arrows 10. The radiator module 2 is brought out liquid-tightly via flanges 12 through the wall of the conduit 1.

As can be seen from the top view of Figure 2, the radiator module 2 consists of three mutually parallel, rod-shaped high-performance Amalgamlam-pen 4, which are protected by a common cladding tube 3 made of quartz glass in front of the flowing water. The

Amalgam lamps 4 are each designed for a nominal power of 450 watts. They each have a cylindrical lamp bulb 7 made of quartz glass with an outer diameter of 28 mm to a total length of 1, 6 m. The lamp bulb 7 extends around a central axis 6 and encloses a discharge space 8, in which helical electrodes 9 protrude from both front ends. The ends of the lamp bulb 7 are provided with pinches 5 for the vacuum-tight implementation of the electrical connections 11 of the electrodes 9.

The cladding tube 3 has an oval cross section as seen from the view in Figure 3. Its smaller inner diameter is 32 mm and its larger inner diameter is 95 mm. The oval cladding tube 3 is arranged in the conduit 1 so that the pointed sheath tube ends of the oval extend in the flow direction 10 and in the opposite direction.

In the following, the radiator module 2 according to the invention and its effect in the degerming plant will be explained in more detail with reference to FIG. 3 in comparison with a traditional radiator module 42 according to FIG.

In both figures, flow lines 16 around the radiator module 2 or 42 are indicated schematically. In addition, directional arrows 17 schematically show the radial radiation intensity of the radiator module 2; 42. The radiator module 42 according to the prior art consists of a circular cross-section casing 43 and a coaxial with the longitudinal axis Hüllrohr- arranged amalgam lamp 44 with also circular cross-section. The radially uniform radiation profile 49 of the radiator module is indicated by direction arrows 17 of the same length. In addition, in the figure, a radial radiation diagram is schematically drawn, in which the radiation intensity "I" in relative unit against the distance "r" from the cladding tube center axis in cm is plotted on the y-axis. Also in this graph, a substantially rotationally symmetric radial radiation profile 49 results around the longitudinal axis of the cladding tube. This means that the radiation intensity around the cladding tube 43 is the same in all directions; there is neither a pronounced minimum nor a maximum. In contrast, the radiator module 2 according to the invention shows a radial radiation diagram, as shown schematically in FIG. The overall radiation profile 19 is not rotationally symmetrical and resembles, for example, the radiation behavior of the dipole of a radio antenna. The radiation intensity shows a maximum 20 in the direction perpendicular to the longitudinal axis 18 of the conduit tube 1 and in the direction perpendicular to the longitudinal axis of the cladding tube, and a minimum 21 in the direction of the longitudinal axis 18 of the conduit 1 and in the direction perpendicular to the longitudinal axis of the cladding tube Intensity at maximum 20 is about 300% higher than at minimum 21 (related to the intensity in the minimum). This radial asymmetrical intensity distribution is indicated by the different lengths of the directional arrows 17, which, however, represent the respective radial radiation intensities only schematically and not true to scale. The radial

asymmetric radiation profile results from superposition of the radiation profiles of the individual amalgam lamps 4 of the radiator module 2.

As a result of the radially asymmetric radiation profile 19, the irradiation dose required can also be achieved in the otherwise low-irradiation flow paths, which are located substantially in the region 23 above and in the region 24 below the radiation module 2, without having to use an overall excessive radiant power. Despite higher radiation intensity in the maxima 20 in the direction of the low-irradiation flow paths, the total power of the radiator module 2 is not higher than that of the radiator module 42 according to the prior art.

Bezuaszeichenliste

Conduit 1

Radiator module 2

Cladding tube 3

Amalgam lamps 4

Bruises 5

Central axis 6

Lamp bulb 7

Discharge space 8

Electrodes 9

Flow direction 10 electrical connections 11

Flanges 12

Streamlines 16 Radial Radiation Intensity 17

Longitudinal axis 18

Total radiation profile 19

Maximum 20

Minimum 21

Area above 2 23

Area below 2 24 conventional radiator module 42nd

Cladding tube 43

Amalgam lamp 44

Total radiation profile 49

Claims

claims

1. Plant for sterilization or treatment of a liquid by means of UVC radiation, with one of the liquid in the flow direction (10) to be flowed through conduit (1) and a transversely to the flow direction (10) arranged cylindrical cladding tube (3) made of quartz glass, within the same and along the cylinder axis (6) there extends a UV radiator unit (2) for generating the UVC radiation, characterized in that the radiator unit (2) generates a radially asymmetric radiation profile (19) of the UVC radiation having an intensity maximum ( 20) in the direction transverse to the cylinder axis (6) of the cladding tube (3) and transversely to the flow direction (10).

2. Plant according to claim 1, characterized in that the radially asymmetric

Radiation profile (1) 9 transversely to the direction of the cylinder axis (6) of the cladding tube (3) and in the flow direction (10) has an intensity minimum (21).

3. Plant according to claim 2, characterized in that the intensity of the UVC radiation at a wavelength of 254 nm in the maximum (20) is at least 50% higher, preferably at least 100% higher than the minimum (21).

4. Installation according to one of the preceding claims, characterized in that the emitter unit (2) comprises a plurality of elongated UV lamps (4) which are arranged parallel to one another and in the flow direction (10) one behind the other, and by a common cladding tube (3) are surrounded.

5. Plant according to claim 4, characterized in that the emitter unit (2) has exactly three UV lamps (4) which are arranged parallel to one another and in the flow direction (10) one behind the other.

6. Installation according to one of the preceding claims, characterized in that the cladding tube (3) has an oval cross section with each opposite two pointed ends and two blunt ends, wherein the cladding tube (3) within the duct (1) is arranged so that that the pointed ends point in the direction of the duct longitudinal axis (18).

7. radiator module, in particular for use in a system according to claims 1 to 6, comprising a of a cylindrical tube (3) surrounded by quartz glass UV lamp unit (2) for generating UVC radiation, characterized in that the UV emitter unit (2) is equipped with a plurality of elongated UV lamps (4) which are arranged parallel to the envelope tube cylinder axis (6) and to one another and which generate in radially asymmetric radiation profile (19) of the UVC radiation, In the direction transverse to the cylinder axis (6) of the cladding tube (3) has an intensity maximum (20).

8. radiator module according to claim 7, characterized in that exactly three UV lamps (4) are provided.

9. radiator module according to claim 7 or 8, characterized in that the UV lamps (4) are designed as high-performance amalgam lamps.

10. radiator module according to one of claims 7 to 9, characterized in that the cladding tube (3) has an oval cross-section.