WO2006053747A1

WO2006053747A1 - Method and device for sterilizing continuously transported containers

Info

Publication number: WO2006053747A1
Application number: PCT/EP2005/012321
Authority: WO
Inventors: Peter Friedrich
Original assignee: Sig Technology Ag
Priority date: 2004-11-18
Filing date: 2005-11-17
Publication date: 2006-05-26
Also published as: DE102004055783A1

Abstract

The invention relates to a method and device for sterilizing upright successively transported containers which are open at the top, particularly cardboard/plastic composite packaging for receiving beverages and/or foodstuffs, wherein the inside of the container is initially cleaned with a sterilizing agent and is subsequently dried with hot air. In order to perform a reliable sterilization without any relative movement of the nozzles in relation to the containers that are to be sterilized, the nozzle (1, 1') is provided with an inner tube (2, 2') and at least one outer tube (3) and the tube nozzle which is formed by the inner tube (2, 2') and which is used for sterilization purposes with the aid of a sterilizing agent and the annular gap nozzle formed by the inner tube (2, 2') and outer tube (3) is provided with air for heating or drying.

Description

Method and device for sterilizing continuously transported containers

The invention relates to a method and a device for sterilizing upright, open-topped and successively transported container, in particular carton / plastic composite packages for receiving beverages and / or food, wherein the container interior is first cleaned with a sterilizing agent and then dried with hot air.

From practice, a variety of different so-called. ^Λ filling machines' are known in which continuously supplied containers such as cardboard / plastic composite packs filled with a certain amount of a given product and then sealed. In order for the product so filled to meet the shelf life requirements, the containers are cleaned before filling or even sterilized in aseptic filling to reliably kill the germs located inside the still empty container.

For this purpose, it is known that the filling machines have, in addition to the actual filling unit, a sterilization unit arranged upstream of this, with the containers, transported one behind the other and open at the top, being passed below the sterilizing unit. The number of sterilizing nozzles arranged one behind the other and the amount of hot air supplied in addition must be matched to the container size, transport speed, etc. become. It is clear that when using a sterilizing agent such as

Hydrogen peroxide (H ₂ O ₂ ) Each sterilized container must be dried out before being filled with hot air.

A disadvantage of the known devices is that the containers are moved transversely to the - substantially vertical - sterile air flow. Although an attempt is made to achieve a vertical sterile air flow through suction devices, which are generally arranged below the containers, the adjacent containers are influenced by vortexes or vortex separations arising as a result of the movement, so that, in the worst case, unsterile air can enter the previously sterilized container.

Although the nozzles for supplying sterilizing agent and hot air are arranged in the vicinity, but always change their position relative to the container moved past the container interior, harmful turbulence and thus possible contamination can not be ruled out. This problem can not be taken into account by the fact that the container of the hot air nozzle and then the sterilizing nozzle are assigned pre-assigned. Due to the sequence of movements necessary here, subsequent contamination can not be completely excluded.

The invention is therefore based on the object, the aforementioned method and the method described in more detail above or the device used for sterilizing containers so and further, that Reliable sterilization and reliable removal of the sterilant can be ensured. In particular, it should be possible to dispense with the relative movement of the required nozzles to be sterilized container as completely as possible.

Procedurally, the solution of the task by the following steps:

Preheating the inner surface of the container by blowing hot air,

Sterilizing the container by spraying a sterilant and

Drying the container by blowing hot air,

wherein the sterilizing agent is passed through a tube nozzle ending above the container and the hot air through an annular gap nozzle arranged around the tube nozzle and wherein the movement of containers and nozzles takes place jointly and continuously.

In terms of apparatus, the object is achieved in that the nozzle has an inner tube and at least one outer tube and that the tube nozzle formed by the inner tube preferably for sterilization with a

Sterilization agent and the annular gap formed by the inner tube and outer tube preferably for warming or drying is preferably provided with air. The invention has thus recognized that by using a "double nozzle" both the required hot air and the sterilizing agent can be centrally introduced into a container so that reliable sterilization is always ensured. since there is no longer any relative movement between the container and the single nozzle arranged centrally above it.

By preheating the inner surface of the container with hot air is reliably ensured that a condensation of the sprayed sterilant on the container wall is greatly reduced.

Another teaching of the invention provides that the temperature of the sterilizing agent in the range between 180 and 300 ° C, preferably at about 200 ° C, and the temperature of the hot air at the nozzle exit during preheating and drying in the range between 150 and 190 ° C. lies. In this way it is possible to heat the container wall by the preheating extremely evenly to a temperature of about 100 ° C. Characterized in that the hot air is blown through the annular die, in contrast to the known from the prior art pipe nozzles not primarily the bottom, but more heated the upper portion of the packing wall. According to a further embodiment of the invention, the amount of sterilizing agent required for sterilizing a container is for example 450 μl / s for a packing volume of 11. The volume flow (at room temperature) of the sterilizing agent is between 5 and 10, preferably 7.5 Nm ³ / h, and that of hot air in the range between 28 and 30 Nm ³ / h.

According to a further preferred embodiment of the invention, the time for preheating, sterilizing and drying is in each case 1 to 3 seconds, preferably 2 seconds. In this way it is possible to achieve a sterilization in continuously moving containers in a period of less than 6 seconds.

As a sterilizing agent is preferred

Hydrogen peroxide (H ₂ O ₂ ) used. However, other chemical sterilants for the inventive method can be used.

Another teaching of the invention provides that the inner tube at the nozzle outlet is shorter than the outer tube. Preferably, the clear cross-sectional areas of inner tube and outer tube are the same size. It is readily apparent that, depending on the size of the container and the time available, different spray characteristics can be set by means of the parameters of the clear cross-sectional areas and the distance between the two tube ends in order to achieve optimal sterilization. In experiments, it has been found that the clear cross-sectional areas for each nozzle are between 150 and 300 mm ² , preferably between 176 (pipe nozzle diameter: 15 mm) and 254 (pipe nozzle diameter: 18 mm).

According to a further embodiment, it is provided that a plurality of nozzles are arranged radially on a plurality of containers receiving sterilizer. In this way, it is possible that the treatment steps of preheating, sterilizing and drying can take place immediately after one another, wherein the position of the container to be sterilized does not change during the sterilization process to the nozzle arranged above it. The system can be optimized via the wheel diameter or the number of container stations and nozzles arranged on the wheel, as well as the rotational speed, since the residence time of the containers to be sterilized on the sterilizing wheel can be as short as possible before the containers are subsequently transferred to a filling station or to a filling wheel be handed over.

The invention will be explained in more detail with reference to a drawing illustrating only preferred embodiments. In the drawing show:

1 is a schematic perspective view of the position of a nozzle according to the invention to the underlying container,

2 shows a cross section through the nozzle outlet of a first embodiment of a nozzle according to the invention and Fig. 3 shows a cross section through the nozzle outlet of a second embodiment of a nozzle according to the invention.

Fig. 1 shows an upright, open-topped package P under a sterilizing nozzle 1, wherein the sterilizing nozzle 1 is arranged centrally above the package P and above it. Due to the simultaneous and uniform movement of the sterilizing nozzle 1 and the package P, the process steps of preheating, sterilizing and drying can take place in the shortest possible time in succession, without undesirable turbulence being caused by a relative movement.

FIGS. 2 and 3 show two different nozzle outlets. In Fig. 2, first, a nozzle 1 is shown, in which an inner tube 2 and a concentrically arranged around outer tube 3 are provided, which are the same length at the nozzle exit. Preferably, the clear cross-sectional area of the inner tube 2 may be the same size as the clear cross-sectional area of the annular gap nozzle formed from the inner tube 2 and outer tube 3.

In Fig. 3, a nozzle 1 'is shown, in which the inner tube 2' is shorter than the outer tube 3 is formed. Increasing the diameter of the outer tube 3, the temperature of the packing wall increases towards the top. By changing the nozzle geometry, an optimal adaptation to the pack P to be sterilized can be achieved.

Claims

PATENT APPLICATIONS

1. A method for sterilizing upright, open-topped and successively transported container, in particular carton / plastic composite packages for receiving beverages and / or food, wherein the container interior is first cleaned with a sterilizing agent and then dried with hot air, the following steps are as follows:

Preheating the inner surface of the container by blowing hot air,

Sterilizing the container by spraying a sterilant and

Drying the container by blowing hot air,

2. Method according to claim 1, wherein the temperature of the sterilizing agent at the nozzle outlet is in the range between 180 and 300 ° C, preferably at about 200 ° C.

3. The method according to claim 1 or 2, wherein the temperature of the hot air at the nozzle outlet during preheating and during drying is in the range between 150 and 190 ° C, according to claim 1 or 2, d a s.

4. The method of claim 1, wherein the amount of sterilant required for sterilizing a container is 450 μl / s.

5. The method according to any one of claims 1 to 4, characterized in that the volume flow (at room temperature) of the sterilizing agent is between 5 and 10 Nm ³ / h, preferably at 7.5 Nm ³ / h.

6. The method according to any one of claims 1 to 5, characterized in that the volume flow (at room temperature) of the hot air is between 28 and 30 Nm ³ / h.

7. The method according to any one of claims 1 to 6, wherein the time for preheating, sterilizing and drying is in each case 1 to 3 seconds, preferably 2 seconds, is.

8. The method according to any one of claims 1 to 7, characterized in that hydrogen peroxide (H ₂ O ₂ ) is used as the sterilizing agent.

9. A process according to any one of claims 1 to 8, wherein the treatment steps of preheating, sterilizing and drying occur immediately after one another.

10. The method of claim 9, wherein the position of the container relative to the nozzle does not change during the treatment steps of preheating, sterilizing and drying.

11. An apparatus for sterilizing upright, open-topped and successively transported containers, in particular carton / plastic composite packages for receiving beverages and / or foods, with at least one nozzle for introducing a sterilizing agent from above into the containers, characterized in that the nozzle ( 1, 1 ') an inner tube (2, 2') and at least one outer tube (3) and that of the inner tube (2, 2 ') formed tube nozzle for sterilization with a sterilizing agent and the annular gap nozzle formed by the inner tube (2, 2 ') and outer tube (3) is provided for warming up or drying with air.

12. The device according to claim 11, wherein the clear cross-sectional areas of the pipe nozzle and the pipe-gap nozzle are of equal size.

13. The apparatus of claim 11 or 12, d a d u r c h e c e n e z e c h e n e, t a s s the inner tube (2 ') at the nozzle outlet is shorter than the outer tube (3).

14. Device according to one of claims 11 to 13, characterized in that the clear cross-sectional area of each nozzle (1, 1 ') is between 150 and 300 mm ² .

15. The apparatus according to claim 14, characterized in that the clear cross-sectional area of each nozzle is between 176 and 254 mm ² .

16. The device according to claim 11, wherein a plurality of nozzles are arranged radially on a sterilization wheel receiving a plurality of containers.