CN112805039A

CN112805039A - Method and device for sterilizing preforms or containers formed therefrom

Info

Publication number: CN112805039A
Application number: CN201980065417.7A
Authority: CN
Inventors: M·格哈茨; T·黑罗尔德
Original assignee: KHS Corpoplast GmbH
Current assignee: KHS GmbH
Priority date: 2018-10-02
Filing date: 2019-10-01
Publication date: 2021-05-14
Also published as: EP3860661A2; DE102018124287A1; WO2020070097A3; WO2020070097A2

Abstract

The invention relates to a method and a device for sterilizing preforms for producing containers formed by pneumatic or hydraulic pressure or for sterilizing containers formed in this way, wherein the preforms (P) or the containers are sterilized by means of a sterilizing steam. Undesired condensation of the sterilization vapor not entering the preforms or containers to be sterilized but reaching other components or components of the sterilization space or sterilization device which are subjected to the sterilization vapor is at least partially prevented by either heating the components or components (20) and/or liquefying at least a portion of the sterilization vapor by condensation on the cooling elements (10, 11, 12, 13).

Description

Method and device for sterilizing preforms or containers formed therefrom

Technical Field

The present invention relates to a sterilization method and a sterilization apparatus for sterilizing parisons ("preforms") used for manufacturing containers shaped by pneumatic (blow) or hydraulic pressure, in particular the pressure of the fluid to be filled, or for sterilizing containers shaped in this way.

The invention furthermore relates to a method and a device for producing containers from parisons, which are shaped by pneumatic pressure (blow-moulding pressure) or hydraulic pressure, in particular the pressure of the fluid to be filled, wherein the parisons are sterilized or the containers shaped from the parisons by pneumatic pressure or hydraulic pressure by means of the above-described sterilization method and sterilization device.

Background

Blow-molded containers are usually produced in that a parison ("preform") made of a thermoplastic material (for example PET polyethylene terephthalate) is expanded by applying a blowing pressure to a blow mold (blast) in order to be subsequently filled with a filling material (in particular a fluid) in a subsequent filling station. Depending on the application and the filler, in addition to a plurality of further production steps, it is also necessary here to subject the preforms or the containers blow-molded therefrom to a blowing process before the filler is introducedThe vessel is sterilized. For this purpose, methods and devices are known which: the method and the device are used to subject the parison (or container) to a sterilizing agent, such as a sterilizing vapor having hydrogen peroxide (H)₂O₂) Or peracetic acid or other chemical disinfectants and water vapor. Methods and apparatuses of this type are disclosed in documents DE102010032336, EP1941913, US 2008/0152538, EP 2394950.

It is also known to expand a parison into a blow mold by the pressure of the fluid to be filled, so that molding and filling are a common process. A corresponding apparatus for producing filled containers from parisons (i.e. a combined forming and filling apparatus) is known from document WO 2011/076167. Depending on the type of filling, here too, sterilization of the parison (or container) is generally required.

Here, a problem with sterilization may be that at least a small amount of sterilization agent does not reach into the preforms (or containers) to be sterilized, but rather into the surrounding area, and onto other parts or components (e.g., conveying and conveying devices, guides, etc.) of the sterilization space (or sterilization apparatus) involved. Furthermore, since the disinfecting agent generally has an increased temperature compared to these regions and components (for example between approximately 100 ℃ and approximately 130 ℃), there is the risk that the (vaporous) disinfecting agent condenses in these regions and on these components or structures.

Especially in the case of disinfectants with hydrogen peroxide, the condensate may then lead to salt-like deposits (Ablagerung) which are difficult to remove and may cause damage due to corrosion and other problems.

Furthermore, there is also a risk of condensate dripping into the preforms (or containers) to be sterilized, as it accumulates on these parts or components located above the opening of the preforms (or containers). This may result in an increased concentration of disinfectant in the preform or subsequently filled container, which is naturally undesirable.

Disclosure of Invention

The object of the invention is therefore to provide a sterilization method and a sterilization device for sterilizing parisons (preforms) which are used for producing containers shaped by pneumatic or hydraulic pressure, or for sterilizing containers shaped in this way, whereby the above-mentioned problems of deposits and undesired condensation (or accumulation of condensate) in combination with the sterilization steam can be at least partially avoided.

This object is achieved with a sterilization method according to claim 1 and a sterilization device according to claim 8.

Thus, according to the invention, condensation of the sterilisation steam on such parts and components, which is undesirable, is at least partially prevented in that these parts or components are either heated to a temperature which is preferably at least as high as the condensation temperature of the sterilisation steam; and/or liquefying at least a portion of the sterilization vapour by condensation on a cooling element (hereinafter also referred to as "condensation trap") and thereby avoiding the above-mentioned undesired condensation.

These two measures can be applied independently of one another or in combination with one another, depending on the type of disinfectant, the configuration of the disinfection space (or disinfection apparatus) and other factors.

This solution can be used not only for sterilizing preforms but also for sterilizing containers formed from the preform by means of pneumatic or hydraulic pressure, and is preferably a component of a blow-molding apparatus (or a blow-molding method) for blow-molding containers from thermoplastic material.

Furthermore, the solution can also be a component of a production plant (or production method) for producing filled containers from preforms, wherein the preforms are expanded by the (hydraulic) pressure of the fluid to be filled into blow-molding molds, so that the forming and filling of the containers are a common process.

The dependent claims contain advantageous developments of the invention.

The condensate trap (kondensationfallen) is preferably merely a cooling element provided for the above-mentioned purpose, which is used, for example, in conjunction with a collecting basin (auffangwan), which is arranged in such a way that the condensate formed is specifically dripped into or removed from the collecting basin.

Such a collection basin may contain a medium (e.g., water or other liquid) for diluting or neutralizing the collected condensate, or may contain a catalyst for breaking down the condensate into less chemically aggressive substances.

In the case of hydrogen peroxide as disinfectant, such a catalyst can be, for example, platinum, which is bonded to a support matrix introduced in the collection basin. Instead of or in addition to platinum, it is also possible to use heavy metal ions (such as, for example, Mn)²⁺Ions) or enzymatic or other catalysts, thereby decomposing the hydrogen peroxide into water and oxygen.

Alternatively or additionally, it is preferred to heat such parts or components: the disinfectant falling on these parts or components is particularly disadvantageous or critical for further production processes, such as the elements mentioned at the outset which are located above the opening of the preform (or container) to be disinfected.

Furthermore, the condensate trap and/or the heated component or component are preferably mounted so as to be replaceable, so that the production process does not have to be interrupted for cleaning the condensate trap (or the heated component or component).

Furthermore, the condensate trap is preferably designed as a hollow body through which a liquid or gaseous cooling medium can be conducted.

The heated component or component can likewise be designed as a hollow body through which a liquid or gaseous heating medium is conducted.

Preferably, these components or parts can however be electrically heated or provided with an electrical heating source (e.g. an electrical resistance heater), which can also be subsequently mounted on these components or parts and/or mounted exchangeably.

The condensation trap is preferably arranged in the flow region of the at least one outlet for disinfectant.

According to one refinement, the sterilization steam is discharged via one or more statically arranged discharge devices (such as, in particular, nozzles) by which the preforms are guided along a linear, circular, curved or other transport path, in which case the condensation trap and/or the heated component or component is preferably likewise arranged in a stationary manner and preferably along at least a part of the transport path.

According to one refinement, the sterilization vapor is discharged via one or more movably arranged discharge devices (such as, in particular, nozzles arranged on wheels) which, during the discharge of the sterilization vapor, follow the preforms along a part of their transport path, in which case, in addition or alternatively to the above-described stationary condensation trap and/or stationary heated component or component, preferably a condensation trap and/or heated component or component is provided: they are arranged to travel with these output means at least along a part of the transport path.

Preferably, both the condensate trap and the heated component or component are formed from metal or have a metal surface.

Drawings

Further details, features and advantages of the invention result from the following description of preferred embodiments with reference to the drawings. Wherein:

FIG. 1: a first 3D view of a first embodiment of the device according to the invention;

FIG. 2: a second 3D view of the first embodiment according to fig. 1;

FIG. 3: a first 3D view of a second embodiment of the device according to the invention;

FIG. 4: a second 3D view according to the second embodiment of fig. 3;

FIG. 5: a first 3D view of a third embodiment of the device according to the invention;

FIG. 6: a second 3D view according to the third embodiment of fig. 5; and

FIG. 7: third 3D view of the third embodiment according to fig. 5.

Detailed Description

Fig. 1 and 2 show the principle structure of a first embodiment of the device according to the invention, which is generally arranged in a sterilization space enclosing the device.

The basic components are a first wheel 1 to which the preforms P to be sterilized are fed, and which first wheel 1 is driven in a counterclockwise manner in the top views of fig. 1 and 2, and a second wheel 2 which rotates in a clockwise manner and receives the sterilized preforms P from the first wheel 1 and feeds them to a further processing station located in the apparatus for blow-moulding containers.

The two

wheels

1, 2 are usually recessed wheels

Is formed and has voids (recesses) arranged along its circumference, which are dimensioned such that preforms P can be held in each case with their openings oriented substantially vertically upwards in these voids (recesses). The two

wheels

1, 2 can also be embodied as pincer wheels

On these clamp wheels, the preforms are held by means of clamp elements.

The preforms P are fed and placed into the recesses of the first wheel 1, the sterilized preforms P are transferred to the second wheel 2 and further transported to the next processing station, which are carried out in a manner known per se and are not further elucidated here.

Above the first wheel 1 there is a supply 3 for a sterilizing agent, typically sterilizing steam and for example with hydrogen peroxide, peracetic acid and/or other chemical sterilizing agents and water and hot air and for example at a temperature of between about 100 ℃ and about 130 ℃.

The supply device 3 ends with a fixed nozzle, which is located above the recess of the first wheel 1 and is directed towards the opening of those preforms P passing under the nozzle, so that the sterilizing steam coming out of the nozzle reaches into the preforms P.

Since the sterilization steam is continuously discharged, it also enters the gap between two adjacent preforms P during the rotation of the first wheel 1 and subsequently condenses, in particular on the components of the first wheel 1 and on the guides located thereunder and on other components and areas of the sterilization space. This (as described above) leads to salt-like deposits and also to corrosion damage in the disinfection space. This risk also exists in the case of pulsed output of the sterilisation vapor.

To avoid this, in the first embodiment shown in fig. 1 and 2, a condensation trap is provided, which has at least one

cooling element

10, 11, 12, 13, through which a liquid or gaseous cooling medium (e.g. cold water) is conducted via the connection 131 at such a temperature that the sterilization vapor reaching the cooling element condenses thereon as far as possible.

At least one cooling element is arranged such that it is located in the flow region (or surroundings) of the nozzle, i.e.: the sterilization agent is applied as much as possible, and does not reach the preforms P guided past under the nozzle.

In fig. 1 and 2, four

such cooling elements

10, 11, 12, 13 are provided, wherein the first cooling element 10 and the second cooling element 11 are located above the first wheel 1, and the third cooling element 12 and the fourth cooling element 13 are located below the first wheel 1.

Furthermore, a basin 14 for collecting condensate dripping from the cooling elements is arranged below the cooling elements.

The first cooling element 10 and the second cooling element 11 are each inclined obliquely outwards with respect to the horizontal plane in the radial direction of the first wheel 1, so that condensate falling on these

cooling elements

10, 11 does not drip onto the first wheel 1 and onto the openings of the preforms P, but flows into the basin 14.

The third cooling element 12 and the fourth cooling element 13 are each arranged substantially vertically below the first wheel 1 and completely or partially above the basin 14, so that the falling condensate flows directly into the basin 14.

As mentioned above, such a collection basin may, for example, contain water or other liquid or catalyst, whereby the received condensate is diluted or neutralized (or chemically decomposed) in order to at least reduce its chemical aggressiveness.

Fig. 3 and 4 show the principle of a second embodiment of the device according to the invention. The same or mutually corresponding parts and components as in the first embodiment are denoted by the same reference numerals.

The essential feature of this embodiment is that instead of the first cooling element 10 and the second cooling element 11, stationary

electric heating elements

20, 21 are provided, which

heating elements

20, 21 have electrical connections 22. The

heating elements

20, 21 preferably comprise an electrical heating source 21 (for example in the form of a resistance heater), which electrical heating source 21 generates heat by supplying electrical current via a connection 22. The heating source 21 is mounted on the metal top surfaces 20 so that the generated heat is distributed over these top surfaces 20 by heat conduction.

These top surfaces 20 are located above the openings of the preforms P inserted into the first wheel 1 and extend along at least a part of the circumference of the first wheel 1 (or another running transport path of the preforms P) on both sides of the steam nozzle 3.

The use of these top surfaces 20 generally prevents dust or other dirt from falling into the preforms P.

The heating by the top surfaces 20 also prevents condensation from collecting on the top surfaces 20 and dripping into the preforms. This also relates, for example, to condensate which forms itself on parts or components of the sterilization space, not shown in the figures, which are located above the openings of the preforms and which drips onto the heated top surfaces 20, since it evaporates again immediately on these top surfaces 20.

As described above, it is also possible in principle to use heated top surfaces or other heating elements which are designed as hollow bodies, for example, as the cooling elements in fig. 1 and 2, and which are heated by the supply of hot or hot liquid.

Furthermore, the second embodiment is preferably also provided with

cooling elements

12, 13, namely: corresponding to the third and

fourth cooling elements

12, 13 in fig. 1 and 2, the

cooling elements

12, 13 of this second embodiment are again arranged essentially vertically below the first wheel 1 and completely or partially above the basin 14, so that the falling condensate flows directly into the basin 14 and (as described above) can be diluted, neutralized or chemically decomposed there, if necessary.

Fig. 5 to 7 show the principle of a third embodiment of the device according to the invention. Parts and components that are identical or correspond to one another to those of the first and second embodiment are also denoted by the same reference numerals.

The essential difference from the first and second embodiments is that instead of a stationary first upper nozzle 31, a plurality of first upper nozzles 31 are provided, which travel together with the transport of the preforms P, and the disinfectant is dispensed into the preforms P via the first upper nozzles 31.

A further difference is that the third embodiment preferably also has a plurality of second lower nozzles 32, which second lower nozzles 32 are likewise not arranged stationary but in a traveling manner together with the transport of the preforms P and serve to load the outside of the preforms with the sterilization steam.

The first nozzle 31 and the second nozzle 32 are preferably fed with sterilizing steam by means of a common supply device 3 or by means of an upper supply device and a lower supply device independent of each other.

Finally, this third embodiment is preferably also provided with a stationary cooling element 12, which stationary cooling element 12 is in turn arranged substantially vertically below the first wheel 1 and above the stationary basin 14, so that the falling condensate flows directly into the basin 14 and (as described above) can be diluted, neutralized or chemically decomposed there, if necessary. In contrast to the first and second embodiments, however, the cooling element 12 and thus the basin 14 preferably extend along at least a portion of the preform transport path (i.e., along the circumference of the first wheel 1 according to fig. 5 to 7), along which the sterilizing steam is output from the first nozzle 31 and the second nozzle 32 onto the preforms P.

In this third embodiment, there is generally no danger that: dirt or condensate can reach the openings of the preforms, so that the heated top surface 20 according to the second embodiment can be dispensed with. If required, however, such a heated top surface 20 can also be arranged in the third embodiment.

Claims

1. A sterilization process for sterilizing preforms for the manufacture of containers shaped by pneumatic or hydraulic pressure, or for sterilizing containers shaped in this way, in which process the preforms or containers are sterilized by means of a sterilizing steam,

it is characterized in that the preparation method is characterized in that,

the sterilization vapor which does not enter the preforms or containers to be sterilized but which reaches other components or components of the sterilization space or sterilization apparatus which are subjected to the sterilization vapor is at least partially prevented from condensing, either by heating said components or by liquefying at least a part of the sterilization vapor by condensation on a cooling element.

2. The method of claim 1, wherein the first and second light sources are selected from the group consisting of,

wherein not only the heating of the component or member but also the condensation of the sterilisation steam on the cooling element is performed.

3. The method according to claim 1 or 2,

wherein the component or member is heated to a temperature at least as high as the condensation temperature of the sterilizing vapour.

4. Method according to at least one of claims 1 to 3,

wherein the heating of the component or member is achieved by passing an electric current.

5. Method according to at least one of claims 1 to 3,

wherein the heating of the component or component is effected by applying a liquid or gaseous heating medium.

6. Method according to at least one of the claims 1 to 5,

wherein the cooling element is cooled by being loaded with a liquid or gaseous cooling medium.

7. Method for manufacturing containers shaped by pneumatic or hydraulic pressure from preforms, in which method the preforms are sterilized or the containers shaped from the preforms by pneumatic or hydraulic pressure by means of a sterilization method according to at least one of claims 1 to 6.

8. A sterilization apparatus for sterilizing preforms (P) for the manufacture of containers shaped by pneumatic or hydraulic pressure, or for sterilizing containers shaped in this way, in which sterilization of preforms (P) or containers is carried out by means of sterilization steam,

it is characterized in that the preparation method is characterized in that,

the sterilization apparatus includes:

-at least one heat source or heating source (21) for heating a part or component (20) of the sterilization space or sterilization apparatus which is subjected to the sterilization steam not entering the preforms or containers to be sterilized, so as to at least partially prevent the sterilization steam from condensing on said part or component; or

-at least one cooling element (10, 11, 12, 13) arranged to: so that at least a part of the sterilisation vapor is liquefied by condensation on said at least one cooling element (10, 11, 12, 13).

9. The apparatus according to claim 8, having not only the at least one heat source or heating source (21), but also the at least one cooling element (10, 11, 12, 13).

10. The apparatus of claim 8 or 9,

wherein the at least one heat or heating source (21) is an electrical heating source which is arranged on the component or component (20) to be heated and heats the component or component by thermal conduction.

11. Device according to at least one of the claims 8 to 10,

wherein the at least one cooling element (10, 11, 12, 13) and/or the at least one heat source or heating source (21) and/or the component or component (20) heated thereby are mounted on the device in a replaceable manner.

12. Device according to at least one of the claims 8 to 11,

wherein the at least one cooling element (10, 11, 12, 13) is designed as a hollow body through which a liquid or gaseous cooling medium is conducted.

13. Device according to at least one of claims 8 to 12, comprising a collection basin (14) arranged below the at least one cooling element (10, 11, 12, 13) for collecting the sterilisation steam condensed thereon.

14. Device according to at least one of the claims 8 to 13,

wherein the sterilization steam is discharged by one or more stationary discharge devices, by which the preforms (P) or containers formed therefrom are guided along a linear, circular, curved or other transport path, and

wherein the component or component (20) heated by means of the at least one heat source or heating source (21) or the at least one cooling element (10, 11, 12, 13) is arranged in a stationary manner and along at least a part of the transport path.

15. Device according to at least one of the claims 8 to 14,

wherein the sterilization steam is output by one or more output devices (31) which are movably arranged and follow the preforms (P) or the containers formed from the preforms along a part of the conveying path of the preforms or the containers during the output of the sterilization steam, and

wherein the component or member (20) heated by means of the at least one heat source or heating source (21) or the at least one cooling element (10, 11, 12, 13) is arranged to travel with the output device at least along a part of the transport path.

16. Device according to at least one of the claims 8 to 15,

wherein the component or component (20) heated by means of the at least one heat source or heating source (21) or the at least one cooling element (10, 11, 12, 13) is made of metal or has a metal surface.

17. Apparatus for producing containers shaped by pneumatic or hydraulic pressure from preforms, by means of a sterilization apparatus according to at least one of claims 8 to 16 for sterilizing preforms or containers shaped by pneumatic or hydraulic pressure from preforms.