WO2012167857A1 - Method and treatment head for treating containers - Google Patents

Abstract

The invention relates to a method for treating containers, in particular containers made of plastic, by introducing a heated gaseous and/or vaporous treatment medium into the container by means of at least one outlet of a treatment head, wherein the treatment medium is heated in a heat exchanger used as a heater on a heat exchanger surface there before the treatment medium is introduced into the container.

Description

 Method and treatment head for treating containers

The invention relates to a method according to the preamble of claim 1 and to a treatment head according to the preamble of claim 8.

Known is u.a. treating containers, for example in the form of bottles, with a hot sterilizing medium, to sterilize the container interior. As the sterilization medium while a gaseous and / or vaporous carrier component, preferably air or sterile air is used, the (carrier component) hydrogen peroxide, preferably highly concentrated hydrogen peroxide (eg 20% to 35% hydrogen peroxide) dosed in finely divided or darkened form is added. The resulting mixture or sterilization medium is then introduced into the respective container in the heated and vaporized state. For heating, the treatment and / or sterilization medium is conducted along at least one heat exchanger surface of a heat exchanger acting as a heater. At the inner surface of the container, the vaporized hydrogen peroxide forms a hydrogen peroxide condensate film, which is then activated by the heated gaseous and / or vaporous carrier medium to release germicidal oxygen radicals. In order to achieve the highest possible quality of sterilization or the highest possible rate of disinfection, it is necessary to introduce the sterilization medium with the highest possible temperature in the respective container. Especially for containers of sensitive materials, for example plastic containers, e.g. made of PET, but care must be taken that the thermal load of the respective container during treatment or sterilization remains below a limit, the exceeding of which would result in damage or destruction of the container.

The object of the invention is to provide a method for treating containers, in particular of containers made of plastic, in which (method) with an optimal process result, for example in an optimal sterilization, a thermal overload of the respective container is avoided in the treatment. To solve this problem, a method according to claim 1 is formed. A treatment head is the subject of claim 8. The invention is based, inter alia, on the finding that it is at least expedient for the desired treatment result to introduce the treatment medium into the container at a first elevated temperature during the treatment in a first partial phase, so that the container temperature rises relatively rapidly to an increased intermediate temperature during this partial phase and that then subsequently the treatment medium is introduced into the container at a temperature which is reduced in relation to the first temperature, so that during this second partial phase a rise in the container temperature, which is slower than the first partial phase, takes place at the maximum treatment temperature. Despite the very short time that is available for the respective treatment, as well as despite a relatively slow compared to the treatment time temperature control of the heat exchanger of the treatment head this is made possible for the treatment result optimal course of the container temperature by the inventive method reliably.

For the purposes of the invention, "containers" are packages or containers which are customarily used in the foodstuffs sector and especially in the beverage sector, such as bottles, cans, soft packagings, for example those made of cardboard and / or plastic film and / or metal foil.

The term "substantially" or "approximately" in the sense of the invention means deviations from respectively exact values by +/- 10%, preferably by +/- 5% and / or deviations in the form of changes insignificant for the function.

Further developments, advantages and applications of the invention will become apparent from the following description of exemplary embodiments and from the figures. In this case, all described and / or illustrated features alone or in any combination are fundamentally the subject of the invention, regardless of their summary in the claims or their dependency. Also, the content of the claims is made an integral part of the description. The invention will be explained in more detail below with reference to the figures of exemplary embodiments. Show it:

Fig. 1 is a simplified schematic representation of a treatment head of a treatment station for treating or sterilizing containers in the form of bottles with a hot treatment or sterilizing medium, e.g. with a hot hydrogen peroxide-containing sterilization medium;

1 in the region of a metering device for the controlled and metered introduction of finely atomized hydrogen peroxide (aqueous H 2 O 2 solution with high H 2 O 2 concentration) in an air stream;

3 shows in a time-temperature diagram the temperature of the respective container during the treatment or sterilization;

4 shows in a time diagram the temperature of the treatment medium introduced into the container;

Fig. 5 is a simplified block or functional representation of a treatment head according to another embodiment of the invention.

The treatment head, generally designated 1 in FIG. 1, serves to treat, in particular, the interior of containers 2, one of which is shown in FIG. 1 with broken lines in the form of a bottle, with a hot treatment medium. In the illustrated embodiment, the treatment head 1 for sterilizing the containers 2 in the form that in an application phase / activation phase, a hot sterilizing medium, which consists of sterile air and a proportion of vaporized hydrogen peroxide (aqueous H 2 O 2 solution of high concentration), for example via a treatment tube 3 is introduced into the interior of the container 2 and that in this case forming on the inner surface of the container 2 H2O2 condensate through the hot air is activated to release germicidal oxygen radicals. At the end of the treatment, the container 2 is dried, for example by hot air. In this treatment, on the one hand the highest possible temperature for the treatment or sterilization medium is desired, since only at a correspondingly high temperature, the sterilization or sterilization of the container 2 is achieved with the desired quality or sterilization rate. On the other hand, especially in containers 2 made of sensitive materials, such as those made of plastic (eg PET) to avoid a thermal overload of the container 2, which would damage or destruction of the container 2 result.

To provide the hot sterilization medium (air with vaporized H 2 O 2) and preferably also to provide the hot air for drying the container 2 at the end of the respective treatment, the treatment head 1 in a housing 4 an electrically heated and acting as a heater heat exchanger 5 whose temperature In the illustrated embodiment, the heat exchanger 5 is designed as a cylindrical heated block, with a formed on the outer surface, the axis of the heat exchanger 5 and the treatment head helically or spirally enclosing groove which forms a vertical axis BA of the treatment head 1 helically or helically enclosing flow channel 7 together with the inner surface of the housing 4, from the upper region of the treatment head 1 to one with the Beh Andungsrohr 3 associated outlet opening 8 of the treatment head 1 is sufficient.

At the outlet opening 8 remote upper end of the flow channel 7, a first metering device 9 is connected, which serves for the controlled and metered penetration of hydrogen peroxide in an air stream, preferably in a stream of sterile air. For this purpose, the metering device 9 has a metering chamber 10, which communicates on the one hand with an air connection 11 for sterile and pressurized air and on the other hand with the upper end of the flow channel 7. In the metering or mixing chamber 10, a spray nozzle 12 is arranged, which is connected via a line 13, which includes a metering valve 14, with a source of the pressurized hydrogen peroxide in combination. By controlled Operation of the metering valve 14 is metered in via the nozzle 12 and finely distributed H202 introduced into the air flow flowing through the metering chamber 10, so that an air / hydrogen peroxide aerosol is formed. This air / hydrogen peroxide aerosol and the air are heated to the temperature T1 in the heat exchanger 5 or in the first heat exchanger or heater section formed by the entire length of the flow channel 7.

Between the upper end of the flow channel 7 and the outlet 8, a second metering device 9a is connected to the flow channel 7, which is carried out in the same way as the metering device 9, although the introduced via the metering device 9a in the flow channel 7 sterilization medium (LuftTWasserstoffperoxid aerosol ) or the sterile air introduced via the metering device 9a is already heated in the heat exchanger 5 to the temperature T2 which is reduced compared to the temperature T1, because of the shorter second heat exchanger or heater section which forms the flow channel 7 between the metering device 9a and the outlet 8. In the line 16 leading to the air connection 11 of the metering device 9a, a control valve 15 is provided in the illustrated embodiment, with which the air flow to the metering device 9 can be controlled and blocked in the illustrated embodiment.

As a result of the described design, the treatment head 1 can be operated in two stages, in such a way that the sterilization medium prepared in the metering device 9 is heated to the temperature T1 on the first heater section formed by the entire length of the flow channel 7 in a first operating state with the control valve 15 blocked and emerges at this temperature according to the arrow A of Figure 1 at the outlet 8 and is introduced via the treatment tube 3 into the container 2. In a second operating state, further heating of the sterilization medium and of the air takes place on the first heater section formed by the entire length of the flow channel 7. Furthermore, when the control valve 15 is open, heating of the sterilization medium provided with the metering device 9a or the air provided with the metering device 9a also takes place the second heater section, for example at approximately the length of the flow channel 7 so that this proportion of the sterilization medium is heated to the lower temperature T2 and by mixing the differently heated portions of the sterilization medium or the air at the outlet 8 a total temperature T3 for the sterilization medium or for the air which is (total temperature T3) smaller than the temperature T1 but greater than the temperature T2.

By means of this two-stage operation of the treatment head 1, it is possible to control the temperature, which comprises the sterilization medium and the air at the outlet 8, without delay or essentially without delay and thus also the treatment or sterilization process in such a way that the highest possible temperature the sterilization medium optimal sterilization is achieved, but at the same time a thermal load on the container 2 is avoided.

FIG. 3 shows the time profile of the container temperature TB during the treatment process. In the case of the treatment head 1 located in the first operating state, a relatively rapid heating of the respective container 2 from the container outlet temperature TB (0) corresponding to the ambient temperature to the container temperature TB (2) takes place in the partial phase I of the treatment process. In a temporally following and compared to the partial phase I longer phase II then takes place by the treatment head located in the second operating state 1 heating of the container 2 to the container temperature TB (1), which corresponds for example to the temperature limit, in which just no damage or Destruction of the respective container 2 occurs. The temporal temperature increase (temperature gradient) in the partial phase II is substantially lower than in the partial phase I, so that a gentle approach to the container temperature TB (1) is possible. In a temporally following subphase III, the respective container 2 is cooled down to the initial temperature TB (0). The actual sterilization of the container 2, if necessary. With the final drying takes place within the phases I and II. This also means that both the temperatures T1 and T3 are at least equal, but preferably greater than the temperature TB (1), and that during the partial phase I in the first operating state or during the partial phase II in the second operating state of the treatment head 1 in the Container 2 with the temperature T1 and T3 introduced amount of treatment medium or the heat capacity of this amount is sufficient to heat the container 2 in the partial phase I to the temperature TB (2) and in the partial phase II to the temperature TB (1) , The volume flow of the treatment medium at the outlet 8 or at the inlet of the flow channel 7 formed by the metering devices 9 and 9a is kept constant in the partial phases I and II, for example.

During the partial phase III, the respective container 2 is removed from the treatment head and / or treatment head 1 is in a third operating state in which closed with metering valves 14, the control valve 15 and a control valve is closed, which in the air connection 11 of the metering device. 9 leading line is provided.

FIG. 5 shows the block or functional diagram of a further embodiment of the treatment head 1a according to the invention for treating the containers 2 with a hot treatment medium, eg with hot sterile air and / or with a sterilizing medium containing hot hydrogen peroxide. The treatment head 1a consists essentially of a two-stage heat exchanger 5a with the preferably electrically heated heat exchanger stages 17 and 18 and of a switching valve 19 to which the air or the sterilization medium is supplied from a source, not shown. In a first operating state of the treatment head 1a, ie in a first switching position of the valve 19, the treatment medium flows through both heat exchanger stages 17 and 18 in succession, ie a first heat exchanger or heater line, so that the treatment medium then eg the elevated temperature T1 at the outlet of the treatment head 1a has , In a second switching position of the valve 19, the treatment medium flows through only the heat exchanger stage 18, ie a second shorter heat exchanger or Erhitzerstrecke so that it has the reduced temperature T3 at the outlet of the treatment head 1a. While in the treatment head 1 both in the first, as well as in the second operating state of the flow channel 7 in each case over its entire length (first Erhitzerstrecke) is provided by the provided by the metering device 9 portion of the treatment medium and in the second operating state by admixing the only on a partial length In the treatment head 1a in the first operating state, both the heat exchanger stages 17 and 18 or the serial series thereof are heated in the first treatment station 1a and the first heating line formed by the latter in the second operating section of the flow channel 7 (second heating section) and the proportion of the treatment medium provided to the metering device 9a Operating state, only the heat exchanger stage 18 and the second heater section formed by this effect.

The invention has been described above by means of exemplary embodiments. It is understood that numerous changes and modifications are possible without thereby departing from the inventive concept underlying the invention.

LIST OF REFERENCE NUMBERS

1, 1a treatment head

 2 containers

 3 treatment tube

 4 housing of the treatment head. 1

 5, 5a heat exchanger

 6 temperature sensor

 7 flow channel

 8 outlet of the treatment head

 9, 9a metering device

 10 dosing chamber

 11 air connection

 12 nozzle

 13 line

 14 metering valve

 15 control valve

 16 line

 17, 18 heat exchanger stages

 19 control valve

 TB (0) outlet temperature of the container

 TB (2) Temperature of the container 2 at the end of the subphase I

TB (1) Temperature of the container at the end of subphase II

BA Vertical axis of the treatment head 1

Claims

claims 1. A method for treating containers (2), in particular containers (2) made of plastic, by introducing a heated gas and / or vapor treatment medium via at least one outlet (8) of a treatment head (1, 1 a) in the respective container ( 2), wherein the treatment medium before being introduced into the container (2) in a serving as a heater heat exchanger (5, 5 a) of the treatment head (1, 1 a) is heated at a local heat exchanger surface,  characterized,  the treatment head (1, 1a) is operated during the treatment at least in two stages such that in an operating state of the treatment head (1, 1a) the treatment medium for heating to a first temperature (T1) is a first one from the heat exchanger (5, 5a) flows through the formed Erhitzerstrecke and in at least one further operating state of the treatment head (1, 1a) at least a portion of the treatment medium for heating to a second compared to the first reduced temperature (T2, T3) flows through a second heat exchanger formed by the heat exchanger (5, 5a) Preferably, the heater lines lead to the at least one common outlet (8) and / or the at least one further operating state follows in time to the one operating state 2. The method according to claim 1, characterized in that the heat exchanger surface of the second heater section is chosen smaller than the heat exchanger surface of the first heater section, preferably by a relation to the first heater section reduced length. 3. The method according to claim 1 or 2, characterized in that in a first sub-phase (I) of the treatment of the respective container (2), the proportion of the treatment medium, which flows through the first Erhitzerstrecke is greater than that of the proportion of the treatment medium, the flows through the second Erhitzerstrecke, wherein preferably in the first sub-phase (I) of the treatment, the treatment medium flows through only the first Erhitzerstrecke. 4. The method according to claim 3, characterized in that in one of the first sub-phase (I) temporally following second sub-phase (II) of the treatment of the respective container (2), the treatment medium flows through the first and second Erhitzerstrecke or the proportion of the treatment medium, the flows through the second Erhitzerstrecke, is greater than that of the proportion of the treatment medium, which flows through the first Erhitzerstrecke, or  in that, in the second subphase (II) following the first subphase (I) of the treatment of the respective container (2), the treatment medium flows exclusively through the second heater section. 5. The method according to any one of the preceding claims, characterized in that the heater lines of a common flow channel (7) of a single-stage or multi-stage heat exchanger (5, 5a) are formed. 6. The method according to any one of the preceding claims, characterized in that the treatment medium is a gaseous and / or vaporous medium, for example air and / or a sterilization medium containing a suitable for sterilizing active component, for example hydrogen peroxide, in admixture with a gas and / or vaporous carrier component, for example in admixture with air. 7. The method according to any one of the preceding claims, characterized in that the volume flow of the treatment medium is kept constant by the Erhitzerstrecken. 8. Treatment head for treating containers (2), in particular containers (2) made of plastic, by introducing a heated gas and / or vapor treatment medium via at least one outlet (8) of the treatment head (1, 1 a) in the respective container, with at least one heat exchanger (5, 5a) serving as a heater for heating the treatment medium, characterized, in that the treatment head (1, 1a) has at least one first heating section with heat exchanger surface which can be flowed through by the treatment medium to heat the treatment medium to a first temperature (T1) and at least one second heating section with heat exchanger surface which can be flowed through by the treatment medium for heating the treatment medium to a second one first reduced temperature (T2, T3), and that the heaters preferably lead to at least one common outlet. 9. Treatment head according to claim 8, characterized in that the heat exchanger surface of the second Erhitzerstrecke is smaller than the heat exchanger surface of the first Erhitzerstrecke, wherein the second Erhitzerstrecke this preferably has a relation to the first Erhitzerstrecke reduced length. 10. Treatment head according to claim 8 or 9, characterized in that the heater lines are formed by a common flow channel (7) of a one-stage or multi-stage heater (5, 5a). 11. Treatment head according to one of the preceding claims, characterized in that the heat exchanger (5, 5a) or the at least one flow channel (7) has at least two inlets (9, 9a) for the treatment medium to be heated and / or at least two outlets (8). for discharging the heated treatment medium, specifically for forming the at least one first and the at least one second heater section, and / or the at least one valve arrangement (19) is provided for switching and / or regulating the heater sections and / or for closing and / or closing or switching off the inputs and / or outlets (8). 12. Treatment head according to one of the preceding claims, characterized in that within the heat exchanger (5, 5 a) at least two different flow paths or channels (7) are formed for the treatment medium, and that the flow paths or channels (7) by switching and / or rules and / or adjusting at least one within the Heat exchanger (5, 5a) provided for motor driven and / or adjustable guide element are adjustable. 13. Treatment head according to one of the preceding claims, characterized in that an electric heater in the heat exchanger (5, 5 a) is provided, and that with the electric heater, the temperature of the heat exchanger (5, 5 a) and the treatment medium can be regulated. 14. Treatment head according to one of the preceding claims, characterized by at least one metering unit (9, 9a) for a metered addition of a suitable sterilizing active component, for example for the addition of hydrogen peroxide, in a gaseous and / or vaporous carrier component, for example in air.