Apparatus for irradiating liquids

1. Reactor for radiating ultraviolet light into a fluid reaction medium, comprising a housing which encloses a tubular cavity, with a radiation source for generating ultraviolet light and an inner tube which, together with the housing, forms an irradiation chamber which is of annular shape, the irradiation chamber being connected with an inlet and an outlet for the reaction medium and is perfused by reaction medium in the longitudinal direction of the tube, wherein the irradiation chamber is equipped with a vortex generating element selected from the group consisting of a UV transparent helical tube having a flattened cross section as said irradiation chamber, a rotatable cylindrical stirrer within said irradiation chamber, and helical ducts disposed circumferentially on the inner wall, the outer wall, or both of the irradiation chamber, wherein the cross-sectional profile of the ducts is rectangular, trapezoidal or half-round.

2. Reactor according to claim 1 , wherein the radiation source is disposed in the inner tube and the inner tube is transparent to the ultraviolet light.

3. Reactor according to claim 2 , wherein the inner wall of the housing has a coating comprising a material which reflects UV radiation.

4. Reactor according to claim 1 , wherein the radiation source is disposed outside the housing and the housing is transparent to the ultraviolet light.

5. Reactor according to claim 4 , wherein the wall of the inner tube has a coating comprising a material which reflects UV radiation.

6. Reactor according to claim 1 , wherein said vortex generating element is a UV transparent helical tube, having a flattened cross section, as said irradiation chamber.

7. Reactor according to claim 6 , wherein the cross section of the helical tube is rectangular, oval, half-round or trapezoidal.

8. Reactor according to claim 1 , wherein said vortex generating element is a rotatable cylindrical stirrer.

9. Reactor according to claim 1 , wherein said vortex generating element is one or more helical ducts which are disposed circumferentially on the inner wall, the outer wall or both, of the irradiation chamber.

10. Reactor according to claim 9 , wherein the cross-sectional profile of the ducts is rectangular, trapezoidal or half-round.

11. Reactor according to claim 9 wherein the ducts have a depth of from 1 to 100 mm and a mean width of from 1 to 200 mm in the cross-sectional profile.

12. Reactor according to claim 9 , wherein the ducts are of helical design and have a pitch of from 3 to 30°.

13. Reactor according to claim 9 , wherein the irradiation chamber is of open construction over its full length in the direction of the tube axis of the inner tube.

14. Reactor according to claim 9 , wherein the outer wall of the irradiation chamber, and the ducts, are formed by a corrugated hose.

15. Reactor according to claim 9 , wherein baffles are disposed on the wall of the irradiation chamber.

16. Reactor according to claim 1 , wherein the design of the inlet is such that the reaction medium enters the irradiation chamber tangentially.

17. Reactor according to claim 16 , wherein the ratio of the length of the reactor to the diameter of the housing is limited to L/D<100.

18. Reactor according to claim 1 , wherein the design of the inlet is such that the reaction medium enters the irradiation chamber radially.

19. Reactor according to claim 1 , wherein the design of the inlet is such that the reaction medium enters the irradiation chamber axially.

20. Reactor according to claim 1 , wherein at least one UV sensor comprising a measuring device for measuring the UV intensity of the radiation source is disposed on the reactor.

21. Reactor according to claim 1 , wherein at least one UV sensor comprising a measuring device for measuring the UV intensity in the irradiation chamber is fitted in the top or bottom region of the reactor.

22. Method for irradiating and sterilizing fluid media which comprises irradiating and sterilizing said fluid media with the reactor of claim 1 .