APPARATUS AND METHOD FOR TREATING FOODSTUFF CONTAINERS

Abstract

The invention relates to an apparatus for treating foodstuff containers by spraying with a biocide-containing treatment liquid in at least one treatment zone (Z1-Z4) equipped with spraying means (B) for spraying the containers, the apparatus further comprising transport means for transporting the containers through the treatment zones (Z1-Z4), at least one generator (G1) for producing a biocide solution, at least one heating device for heating the treatment liquid, lines for supplying the biocide solution from the generator (G1) to the treatment zones (Z1-Z4) and, optionally, to at least one further biocide consumer device (BV1, BV2), lines for supplying the treatment liquid to the treatment means (B), as well as valves (V1-V7), controllable metering devices and pumps required for controlling the liquid flows, characterized in that a) the apparatus comprises at least two generators (G1, G2) for producing the biocide solution, and b) the generators (G1, G2) are connected or connectable neither directly nor indirectly to one another, but via corresponding feed lines to all treatment zones (Z1-Z4) and to any further biocide consumer device (BV1, BV2); and a method for operating such an apparatus.

Claims

1. An apparatus for treating tightly sealed foodstuff containers by spraying with a treatment liquid containing at least one biocide in at least one treatment zone equipped with a plurality of spraying means for spraying said containers, the apparatus further comprising transporting means for transporting the containers through the treatment zones, at least one generator for producing a solution of the at least one biocide, at least one heating device for heating the treatment liquid, lines for supplying the biocide solution from the generator to the at least one treatment zone, lines for supplying the treatment liquid to the spraying means, as well as valves required to control the liquid flows, adjustable metering devices and pumps, characterized in that: a) wherein said at least one generator comprises at least two generators for producing the biocide solution, and b) the generators are not connected nor connectable neither directly nor indirectly with one another, but are connected or connectable with any treatment zones and any further biocide consumer devices via corresponding feed lines.

2. The apparatus according to claim 1, characterized in that the feed lines leading from the generators to the treatment zones and any further biocide consumer devices are connected or connectable with one another via mixing valves.

3. The apparatus according to claim 1, characterized in that at the outlet of each generator, a check fitting is provided.

4. The apparatus according to claim 1, characterized in that the treatment liquid is an aqueous solution of the at least one biocide, and the generators are for producing an aqueous solution of the at least one biocide at varying concentrations which are higher than the biocide concentration of the treatment liquid, and each include feed lines for one or more biocide precursor solutions.

5. The apparatus according to claim 4, characterized in that the generators are for producing an aqueous chlorine dioxide solution according to the peroxodisulfate chlorite process and each include feed lines for aqueous solutions of peroxodisulfate and of chlorite from corresponding storage tanks.

6. The apparatus according to claim 1, characterized in that the apparatus it is for pasteurizing foodstuffs enclosed in the containers, and comprising at least one heating device for heating the treatment liquid to more than 60° C.

7. The apparatus according to claim 1, characterized in that the apparatus comprises at least another biocide consumer device, selected from devices for rinsing, washing, filling and sealing of the containers as well as for lubricating the transport means for the containers.

8. The apparatus according to claim 1, characterized in that the treatment zones are parts of a tunnel-type pasteurizer, plate-type pasteurizer or chamber pasteurizer.

9. The apparatus according to claim 1, characterized in that the apparatus further comprises measuring sensors for temperatures and/or concentrations of the liquid flows, which are connected to a controller for controlling the heating devices, metering devices, pumps and/or valves.

10. The apparatus according to claim 1, characterized in that the apparatus further comprises at least one mixing chamber for mixing the biocide solution produced in at least one generator with fresh water and/or for mixing of at least two biocide solutions produced by different generators with one another before entering the corresponding treatment zone or into another biocide consumer device.

11. The apparatus according to claim 1, characterized in that the apparatus further comprises one of more of: one or more feed lines for fresh water; means for collecting used treatment liquid; further heating and cooling devices; and means for exhausting the atmosphere surrounding the treatment zones.

12. A method for treating tightly sealed foodstuff containers by spraying with a treatment liquid containing at least one biocide using an apparatus according to claim 1, the method comprising the steps: producing a solution of the at least one biocide in the at least two generators which are neither directly nor indirectly connected to one another; directing the biocide solution to at least one treatment zone equipped with a plurality of spraying means, each generator being connected or connectable with any treatment zones and any further biocide consumer devices; mixing the treatment liquid with the biocide solution; and, spraying the containers with the treatment liquid via the spraying means, while they are being transported through the treatment zones.

13. The method according to claim 12, characterized in that the containers are sprayed with an aqueous solution of at least one biocide, and an aqueous solution of the at least one biocide is produced in the generators at varying concentrations, which are higher than the biocide concentration of the treatment liquid.

14. The method according to claim 12, characterized in that the foodstuff enclosed within the containers are pasteurized with the treatment liquid which is heated to more than 60° C., prior to spraying the containers.

15. The method according to claim 12, characterized in that the biocide concentration of the biocide solutions and the treatment solutions produced in the generators are measured, and that the amounts of each liquid flow supplied to the at least one treatment zone are controlled using the measured values.

16. The method according to claim 12, characterized in that the generators, aqueous biocide solutions are produced at least periodically at varying concentrations.

17. The method according to claim 12, characterized in that treatment liquid is introduced into the individual spraying means of a treatment zone at varying temperatures.

18. The method according to claim 12, characterized in that fresh water is continuously or intermittently supplied and/or the atmosphere surrounding the treatment zones is extracted.

19. The method according to claim 12, wherein, in the generators, an aqueous chloride dioxide solution is produced according to the peroxodisulfite chlorite process from peroxodisulfate and chlorite.

20. The method according to claim 12, wherein biocide solutions from different generators having varying concentrations are mixed with one another prior to entering into a treatment zone and/or into any further biocide consumer device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The invention is described in more detail below with reference to non-limiting preferred examples and with reference to the accompanying drawings showing the following:

[0050] FIG. 1 is a schematic view of a relatively simple embodiment of an apparatus and method according to the present invention; and

[0051] FIGS. 2 and 3 are schematic views of further preferred embodiments of the invention with somewhat more complex interconnection.

EXAMPLES

[0052] As mentioned above, FIG. 1 schematically shows a comparatively simple embodiment of the apparatus and the method of the present invention, wherein, however, only the lines and valves necessary for the connection of the components actually shown are drawn, but not, for example, the pumps also necessary for the operation of the apparatus, as well as heating and cooling devices, further valves, controllable metering devices, regulators and controllers. For a person skilled in the art, the components to be provided for smooth operation result quite naturally from the text description. With regard to the transport of liquids through the apparatus, it is assumed herein, for example, that a pump with the required pumping power is integrated in each component from which a liquid flow is delivered, such as in generators or storage tanks.

[0053] In particularly preferred embodiments, the present invention also relates to operating tunnel-type pasteurization systems in which a hot treatment liquid is used for pasteurizing foodstuffs, to which biocide solution from the generators is added. Therefore, it is further assumed herein that the apparatus comprises at least one heating device, not shown, in which water is heated to high temperatures, e.g., to 80-90° C., in order to feed the spraying means, in particular the spraying means in the center of the respective treatment zones, and to heat the food containers transported thereunder past the spraying means to above 60° C., preferably to at least 70° C., even more preferably to about 80° C. Sometimes, evaporators can also be used to heat the containers with steam to the desired temperature, which will condense on the containers and is in turn collected and recycled below the conveyor belt.

[0054] It should also be mentioned that, for simplicity and clarity, only embodiments with two generators are specifically illustrated and discussed herein. However, it is self-evident for the skilled person that the present invention also includes embodiments with more than two generators, where the corresponding components are to be connected analogously in each case.

[0055] FIG. 1a now shows a first simplified flow diagram based on two generators G1, G2, each of which is followed by a check fitting R1, R2 downstream. These are preferably check valves, e.g., spring-loaded ball check valves, but check flaps or backflow flaps can also be used to effectively prevent the biocide solution from flowing back into the generator and thus at the same time the influx of biocide solution produced in another generator, even if the integrated pump should not generate the required pressure due to a malfunction or the like.

[0056] The biocide solution produced in the generators, which is in particular an aqueous biocide solution, is pumped to a plurality of—herein four—treatment zones Z1 to Z4, each comprising a plurality of—herein three—treatment means B represented by circles O.

[0057] It is to be understood that neither the number of treatment zones nor that of the treatment means contained therein is limited thereto. In practice, as previously indicated, each of the treatment zones discussed and illustrated herein particularly preferably represents a tunnel-type pasteurizer, i.e., a tunnel usually being several meters long, in which the foodstuff containers, such as beverage bottles or cans, are placed while they remain therein or are placed, e.g., on a conveyor belt, are supplied from above with a hot liquid from a large number of supply means. According to the state of the art, several tunnel-type pasteurizers—for example, three each according to DE 10 2018 205 009 A1 cited above—are also supplied with treatment liquid by a biocide generator. The maximum number depends primarily on spatial and structural conditions and on the performance of the generator and the pumps, and will generally hardly be more than five. The number of sprayers per treatment zone or tunnel-type pasteurizer, which may be spray nozzles or atomizers, is of course also dependent on the above conditions.

[0058] The treatment zones Z1 to Z4 can each be preceded by a metering device (not shown) which controls the amount of biocide solution supplied to the respective treatment zone, e.g., a computer-controlled pump or the like, wherein this supply may be continuous or intermittent (“pulsed metering”).

[0059] In FIG. 1a, a valve V1 or V2 is provided in flow direction immediately after the check valves R1 and R2, by means of which the supply of biocide solution produced in the respective generator to the apparatus can be completely interrupted. Then, in the embodiment shown here, the inlet of the biocide solution from the respective other generator is shown, where the connection line also comprises a valve, V3, with which the connection can be interrupted, as needed.

[0060] Subsequently, the lines leading from each generator to the treatment zones branch out so that, when the valve V3 is closed, each of the generators G1 and G2 can supply only two treatment zones, i.e., Z1 and Z2 or Z3 and Z4, with treatment liquid. Each of the lines to the individual treatment zones Z1 to Z4 comprises a further valve, V4 to V7, by means of which the supply of treatment liquid to the respective treatment zone can be interrupted.

[0061] The spraying means B, to which the biocide solution is subsequently fed by means of a controllable metering device, if necessary, are preferably connected in parallel, as shown in FIG. 1a. This means that they are supplied with biocide solution at approximately the same pressure. It is also preferred that the supply to the spraying means B is as shown in FIG. 1b, which ensures the same pressure in all lines with the same supply volume. For example, a computer-controlled metering device can be provided at the position marked with “e”.

[0062] FIGS. 1a and 1b also show a preferred embodiment of the invention in which the biocide solution supplied from the generators is not fed into all spraying means B, but only into those at the beginning and end of the treatment zones, i.e., into the first and third spraying means B. In this case, it is assumed that the biocide solution supplied from the generators is not fed into all spraying means B, but only into those at the beginning and end of the treatment zones. It is assumed that the spraying agents B located in the middle of the treatment zones are sprayed (or sprayed) with treatment liquid of the highest temperature, e.g., with hot water at 80-90° C. Since mixing the biocide solution with such hot water would cause the biocide, especially chlorine dioxide, to decompose, mixing takes place only after the water used as the treatment liquid has been reduced by recycling, i.e., by collecting the chlorine dioxide that is present on the surface of the water to be treated. This means that the water that has run down the surface of the containers to be treated is collected below the conveyor belt and the containers at the beginning and end of the treatment zone are sprayed again.

[0063] Furthermore, multi-way valves can be provided at the branching positions a to d of the lines in addition to or preferably as an alternative to valves V1 to V7. For example, valve V3 can be replaced by two multi-way valves at positions a and b, and/or valves V4 to V7 can be replaced by multi-way valves at positions c and d. This provides the additional advantage that the valves V3 can be replaced by two multi-way valves at positions a and b, and/or valves V4 to V7 can be replaced by two multi-way valves at positions c and d. This offers the additional advantage that, when four-way mixers are used, fresh water can be introduced into the respective line at the respective position, for example, to compensate for liquid losses or to dilute the biocide solution, if necessary. However, the inlet of a line supplying fresh water or the like is not limited to multi-way valves at these positions, but can also take place at any other position within the plant.

[0064] Furthermore, for example, instead of some or all of the multi-way mixers, a dynamically operated mixing chamber, as described above, can be provided in each case to improve mixing, which can be advantageous especially if more than two flows need to be mixed.

[0065] In practice, e.g., in tunnel-type pasteurizers particularly preferred according to the invention, the treatment liquid formed by mixing the aqueous biocide solution with the sufficiently cooled water is recycled several times and finally drawn off from the treatment zones, as indicated by the arrows, and—optionally after appropriate purification or treatment—either removed from the treatment zones, or mixed with the water. If necessary, after appropriate cleaning or treatment, it is either disposed of, reused for spraying containers, or fed to other biocide consumers.

[0066] FIG. 2 shows another embodiment of the apparatus or process according to the invention as in FIG. 1, in which again two generators G1 and G2, but now only two treatment zones (e.g., tunnel-type pasteurizers) Z1 and Z2, as well as two further biocide consumer devices BV1 and BV2, supply biocide solution produced therein. For the sake of simplicity, we have omitted here—as well as in the following FIG. 3—the explicit representation of the individual spraying means within the treatment zones.

[0067] Additional biocide consumers in conventional systems for treating foodstuff containers are, above all, devices for rinsing, washing, filling and sealing the containers, as well as devices for lubricating the transport means, e.g., one or more transport belts for the containers (“belt lubrication”). These are also supplied—continuously or intermittently—with biocide solution produced in the generators, if necessary, after dilution of the same with fresh water or other treatment.

[0068] Another main difference to the embodiment of FIG. 1 is that the biocide solution supplied by the generators G1 and G2 to the treatment zones Z1 and Z2 and to the additional biocide consumers BV1 and BV2 is fed in this case directly upstream of the respective biocide consumers Z1, Z2, BV1 and BV2, so that in the case of simultaneous operation of both generators G1 and G2, the supply of biocide solution from one of them can also be interrupted for only one biocide consumer, whereas in the case of the alternative shown in FIG. 1 this is only possible in pairs. This means that it can be set individually for each biocide consumer whether it is to be supplied with biocide solution from one or from both generators—or, in the case of more than two generators, from several or from all generators. In this way, precise control of the biocide solution supplied to each biocide consumer Z1, Z2, BV1 and BV2 can be achieved, even if the biocide solution flows produced in the individual generators differ in some parameters, e.g., having different concentrations of biocide, different volumetric flows or also different temperatures.

[0069] Otherwise, the same options as described above for FIG. 1 apply to the embodiment of the apparatus or method according to the invention shown in FIG. 2. In this case, for example, multi-way valves can also be provided at all line branching positions in addition to or as an alternative to the valves V8 to V15, a supply of fresh water can be provided, etc.

[0070] Finally, FIG. 3 shows a particularly preferred embodiment in which, in contrast to that in FIG. 2, the valves V1, V2 and V8 to V15 are actually each replaced by multi-way mixers M1 to M6. In the feed lines to the four biocide consumers Z1, Z2, BV1 and BV2, the three-way mixers M3 to M6 are provided instead of valves V8 to V15, and the valves V1 and V2 following the check valves R1 and R2 have been replaced by the three-way mixers M1 and M2, into each of which a feed line for fresh water from the fresh water reservoirs FR1 and FR2 also opens. Of course, as mentioned above in reference to FIG. 1, an additional fresh water feed could also be provided in the multi-way mixers M3 to M6 if they are designed as four-way mixers instead of three-way mixers.

[0071] Additionally, FIG. 3 shows storage tanks for aqueous solutions of peroxodisulfate, P1 and P2, and of chlorite, C1 and C2, respectively, which supply both generators G1 and G2 with such biocide precursor solutions via corresponding feed lines, in order to produce the chlorine dioxide solution which is especially preferred according to the invention by the peroxodisulfate chlorite process as biocide solution.

[0072] All of the other options described above will also be applicable analogously to the embodiment shown in FIG. 3. Thus, it will be assumed herein, that both fresh water reservoirs FR1 and FR2 as well as the storage tanks for biocide precursor solutions P1, P2, C1 and C2 will each be equipped with an integrated pump, and any multi-way valve could optionally be substituted by a mixing chamber.

[0073] A number of other modifications and additions which are necessary or desirable for various applications or processes are also known to those skilled in the art in the treatment of foodstuffs and more particularly of beverages, especially in tunnel-type pasteurizers, and consequently, in combination with the features of the invention disclosed herein, also fall within the scope of the appended claims.

[0074] The present invention thus provides a new apparatus and method for treating tightly sealed foodstuff containers by spraying with a biocide-containing treatment liquid, which, compared to the prior art, provide a higher reliability as well as a higher flexibility of the treatment itself.