DD281545A5 - DEVICE FOR UV-IRRADIATION OF FLOWING LIQUIDS AND GASES - Google Patents

Abstract

The invention relates to a device for UV irradiation of flowing liquids and gases and for the initiation of chemical reactions, in particular for the sterilization and purification of water, air and exhaust gases of chemical reactors and thereby achieves high radiation intensity and homogeneity, low flow resistance and high throughput. The apparatus has a quartz glass tube pierced by the medium to be irradiated, which is surrounded by another quartz glass tube and forms with this and with the two located at the tube ends Stirnflaechen an annular space, which is the common development space for electrical discharge between a plurality of arranged on the Stirnflaechen electrode pairs , The electrodes face each other in pairs, form a discharge path in pairs and are connected to independent voltage sources. Fig. 1 {UV emitter for sterilization; Sterilization of air and water; Initiation of chemical reactions by UV radiation; Mercury vapor lamp; radiant intensity; throughput}

Description

For this 2 pages drawings

Field of application of the invention

The invention relates to a device for UV irradiation of flowing liquids and gases for purifying water or air preferably in pressure and vacuum system with very small or very large pipe diameters by killing germs and by splitting or decomposing toxic or aggressive organic contaminants and to initiate chemical reactions. The preferred use of the device is water treatment, purification and decontamination of the waste gases from chemical reactors in the context of environmental protection, and the production of chemical substances by photochemical reactions.

Characteristic of the known state of the art

It is known to use for the purification and sterilization of liquids and gases UV radiation. In the devices preferably used for this purpose, the medium to be irradiated flows through a substantially cylindrical tube, preferably made of quartz glass, inside or outside of which at least one UV radiator is arranged. These devices have in common that a relatively large expenditure on equipment must be driven so that the required during the irradiation of flowing Niedien residence times of the medium on the UV lamp and the necessary irradiation intensities can be achieved. To improve the homogeneity usually several rod-shaped UV burners are used, which in turn makes a large number of beam detectors with the corresponding electrical connections, Vorschaltgoräten and seals, protective tubes, stuffing boxes and more required. In addition, in these known devices the flowing medium, a relatively large flow resistance is opposed, which plays a crucial role, especially at high flow velocities in systems in excess pressure and in vacuum systems.

It has already been proposed to form the UV-Strahiar ice a substantially cylindrical surface forming a tube which either comprises the medium to be irradiated through the tube or is arranged in it. However, the device has the disadvantage that it can not be used for extremely small and oxtrem large pipe diameters. In addition, the maximum deliverable radiation power is limited.

It is also already known from DD WP 215423, H 01 J 61/72, in a radiator whose vessel consists of two at least hexagonal parallel and spaced apart disks and a lateral surface and in which three pairs of electrodes are arranged on this lateral surface to create a common discharge space by such a vessel design. In order to avoid a stroboscopic effect and high ignition safety, long life, better light output and reduced Fertigungsauwand be achieved. These goals are not fulfilled. In the circuit disclosed in this patent, the voltages applied to the pairs of electrodes are interlinked and it is necessary for the unwanted transfer of the discharge from the intended discharge gap between opposite

Electrodes on paths between adjacent electrodes come with uncontrolled overstressing of the electrodes, Wear, inhomogeneity of the emitted radiation and flicker phenomena. The production effort in a polygon

as a discharge vessel is unacceptably high. In addition, a disk-shaped radiator for the dissolved according to the invention

Task of irradiation of flowing liquids and gases completely unsuitable. According to DE OS 3119223, H 01 J, 61/92, it is known in the piston of an electric discharge tube two Insert electrode groups at its ends, namely a group at each end, wcbei each group of an anode and

a cathode exists. The discharge takes place alternating with the anode of the first group and the cathode of the second group alternating with the anode of the second group and the cathode of the first group in time with an alternating voltage with two half-wave rectifiers. The cathodes and the anodes are designed differently according to the particularities of their different functions in the gas discharge by optimization principle, whereby a better efficiency of the converted electric energy and a high radiation intensity can be achieved. The

But discharge tube has the outer dimensions of a stoichiometric radiator or a flat radiator and is for a Use as a UV emitter around a pipe to be irradiated by the medium to be irradiated with the disadvantages already described

afflicted.

It is also a device for sterilizing liquids by UV irradiation according to DE-OS 3624169, A 61 L 2/08,

known, in which an annular space is formed by coaxial cylindrical tubes, parallel to the main axis a partition wall located in this annulus rod-shaped radiator are arranged and the liquid to be irradiated in the wisdom in

Circumferential flows through the annular space. The construction and operation of this device are with great η effort

connected.

The UV emitters are, in order to keep them away from the liquid, inserted into radioprotective protective tubes and condition

a very high flow resistance to the medium to be irradiated.

It is also a device according to EP11776, A 61 L 2/10, known in the perpendicular rod-shaped UV lamps in

an annular space between an outer cylindrical vessel wall and an inner coaxial quartz glass tube are arranged and in which the flowing medium in the annular space and in the Rohrinnem has an opposite flow direction.

Also, this device has a complicated structure and an unacceptably high flow resistance. Object of the invention

It is the object of the invention, in the sterilization and purification and initiation of photochemical reactions in flowing liquids and gases in pipes with very small diameters and in pipes with relatively large diameters eino great reliability of the operation with little maintenance effort a simple structure of the device used for this purpose realize.

Explanation of the essence of the invention The invention is based on the object, flowing gaseous or liquid media to a strong UV irradiation

undergo without the flow is opposed to a significant flow resistance. This is supposed to be a big one

Throughput can be achieved. This object is achieved by a tube of quartz glass through which the medium to be irradiated flows, that of another Quartz glass tube is concentrically surrounded and in which in the annular space thus formed by more than one pair of electrodes

outgoing the UV radiation donating discharge lines are, according to the invention achieved in that at the two

End faces of the annular space in pairs opposite electrodes are arranged, each in pairs one Form discharge path, and that the annulus is the common discharge space of all discharge paths. The inner6 Quartz glass tube has a negligible for the passage of the medium to be irradiated Flow resistance. The pairs of opposing electrodes are connected in pairs to power sources that are connected to each other

without connection - galvanically separated.

In an expedient embodiment, it is 3 or η 3 (n = small integer) electrode pairs, and pairs

opposite electrodes are respectively connected in pairs to mutually unconnected AC voltages derived from a three-phase AC network, for example, the ones not connected to each other

Secondary windings of a three-phase three-phase transformer. In another expedient embodiment, the pairs of opposing electrodes become their voltage sources

by means of a multiplex circuit and electronic switching elements, such as thyristors connected.

In a further embodiment, the pairwise opposite electrodes each zn one DC voltage source, optionally connected to a pulsating Gloich voltage source connected. This is called the number of Electrode pairs 2 or η 2 (n = small integer) are chosen, and according to their function in the discharge process

optimally formed cathodes and anodes are arranged alternately on the front sides of the annular space, whereby a

Gain in homogeneity of the UV radiation and a high possible radiation intensity can be achieved. embodiments

The invention will be explained by way of example with reference to drawings. 1 and 2 each show a side view and a broken longitudinal section through the tube through which the medium to be irradiated flows, which is surrounded by an annular space with the electrode connections, in FIG. 1 this tube with a relatively small tube diameter and in FIG Fig. 2 of this pipe with a relatively large diameter.

In the two representations, the quartz tube 1 through which the medium to be treated flows from is an additional quartz tube 2

surround. They form together with the two at the ends of the quartz tube 1 and the quartz tube 2 arranged

End faces 3 an annular space 4. At the end faces 3 pairs of opposing electrodes 5 are arranged, each

in pairs form a discharge path.

In Fig. 1, the device according to the invention has olive-like hose connections 6, in Fig. 2 flanges 7 for connection to a Piping system.

Claims (6)

1. A device for UV irradiation of flowing liquid Celts and gases through which a medium to be irradiated flows through.) Tube of quartz glass which is surrounded by another quartz glass tube concentrically and in which the annular space thus formed emanates from more than one pair of electrodes. the UV radiation emitting discharge lines are located, characterized in that in pairs opposite electrodes are arranged at the two end faces of the annular space, each of which forms a discharge path, and in that the annulus is the common discharge space of all discharge paths. 2. Apparatus according to claim 1, characterized in that the pairwise opposite electrodes are connected in pairs to voltage sources which are electrically isolated from each other without connection. 3. Apparatus according to claim 1 and 2, characterized in that the paired opposite electrodes are connected to each other unconnected AC voltages, which are removed from a three-phase AC network, for example, from unverbundonen secondary windings of a three-phase AC transformer. 4. Apparatus according to claim 1 and 2, characterized in that the pairs of opposite electrodes are connected to their voltage sources by means of a multiplex circuit and electronic switching elements, for example thyristors. 5. Apparatus according to claim 1,2 and 4, characterized in that the pairwise opposite ble electrodes are connected to a DC voltage source, optionally to a pulsating DC voltage source. 6. Apparatus according to claim 5, characterized in that the cathodes and anodes of the arranged on the end faces of the annular space electrodes are arranged alternately.