US20170360069A1

US20170360069A1 - Method and device for treating foods and/or containers by means of a process liquid

Info

Publication number: US20170360069A1
Application number: US15/538,405
Authority: US
Inventors: Roland Concin; Harald Eder; Christian RINDERER; Matthias Rinderer; Volker Viechtbauer
Original assignee: Red Bull GmbH
Current assignee: Red Bull GmbH
Priority date: 2014-12-22
Filing date: 2015-12-22
Publication date: 2017-12-21
Also published as: AU2015372408B2; JP6673922B2; US12011019B2; US20170360068A1; ZA201704951B; CN107427039B; AT516685A1; AU2015372409B2; CN107427039A8; BR112017013607A2; JP2018506269A; BR112017013614B1; EP3237341B1; BR112017013614A2; EP3237341A1; AU2015372408A1; EP3236775B1; CN107427038A; JP2018508420A; CN107427039A

Abstract

The invention relates to a method and a device for treating foods and/or containers for holding foods. The foods and/or containers are treated in at least one treatment zone by a process liquid, wherein the process liquid is at least partially recirculated into the treatment zone or the treatment zones after completed treatment of the foods and/or the containers. At least one membrane filtration system and at least one UV irradiation apparatus are provided for cleaning and sterilisation of the process liquid.

Description

The invention relates to a method for treating foods and/or containers for holding foods and to a device for treating foods and/or containers for holding foods. In particular, the invention relates to a method and device for treating luxury foods, especially alcoholic and nonalcoholic drinks. The foods and the containers for holding foods are treated with a process liquid in at least one treatment zone, wherein after being discharged from the treatment zone(s) the process liquid is at least partially recirculated into the treatment zone(s) for re-use in the method. For cleaning and sterilisation, at least some or all of the at least partially circulated process liquid is used to form at least one stream of process liquid, and the at least one resulting stream is filtered by at least one membrane filtration system and/or irradiated by at least one UV irradiation apparatus.
Various variations of methods and devices for treating foods and/or containers are known from the prior art. Often the products, for example foodstuffs, and/or the containers are treated by a tempered process liquid, as is e.g. the case in pasteurisation of food products in so-called pasteurisers. In most cases, water or an aqueous solution is used as the process liquid and acts indirectly on the products or directly on the containers.
To avoid creating large quantities of liquid waste and waste water, the process liquid or process water is often at least partially circulated through the device or the treatment zone(s), i.e. the process liquid is re-used in a circulation procedure. However, this approach entails a high potential for dirtying or contamination of the process liquid, especially an increased risk of the growth of germs or pathogenic micro-organisms. Systems for treating products or containers are usually accessible, the conditions by no means consist of controlled air circulation or the like. There are other sources of dirt and germs in addition to the ambient air, for example the operating staff or other people, conveying elements for the containers and products, any cooling equipment for the process liquid, especially air-conditioned cooling towers, or even the process liquid freshly introduced into the method or device itself. Furthermore, contaminants can enter through the treatment process itself, such as through damage to the containers and contaminants in the process liquid caused by the product or through the detaching of particles such as paint particles or the like from the outside of the containers.
In the past a number of methods have been suggested for removing contaminants from a process liquid. These consist of filtration measures for removal of relatively coarse or large particles, such as glass shards, sand, gravel, and the like. An example is EP 2 722 089 A1. EP 2 722 089 A1 describes a device for thermal treatment of products in containers. The containers are sprinkled or sprayed with a process liquid and the process liquid, e.g. water, is recirculated for at least partial re-use. A gravitational sedimentation device is used to clean the process liquid that can separate out coarse-grained or large particles like glass shards or sand.
The methods known from the prior art describe, for example, filtration methods for separating relatively large particles out of a process liquid using separating devices such as conventional mesh sieves, filter bands, or detachable sieves, or in fact sedimentation devices.
However, the measures known from the prior art are not suitable for removing impurities with relatively small particle sizes from the process liquid. This especially affects particle contaminants that cannot be removed by conventional filter sieves and other separating devices, or e.g. do not or only very slowly precipitate out of a process water stream. Furthermore, micro-organisms and pathogenic germs cannot be removed from the process liquid or process water to a sufficient extent in this way. In particular, these previously known measures do not provide an effective means of preventing or at least reducing the reproduction or growth of micro-organisms and germ colonies. This requires extensive use of germ-deactivating chemicals like chlorine or chlorination methods, which chemicals can for the most part be hazardous to health and the environment. In addition, the use of chemicals for disinfection is typically associated with high costs.
In such devices or systems for treating products or foodstuffs, there are furthermore conditions in at least some areas that promote the growth or reproduction of micro-organisms in the process liquid or process water, for example because of a particularly favourable, growth-promoting temperature. These micro-organisms, for example bacteria, fungal spores, but also viruses, can be introduced into the device by fresh process water but also by operating staff or other persons. In general, it cannot be wholly ruled out that micro-organisms may get on the outside of the containers in the course of the treatment and at least partially remain there even after the treatment process.
Particularly problematic in regard to filtration by conventional sieves is the disadvantageous distribution of particle sizes in a typical process water. In particular, the use of chemicals like surfactants favours very small particle sizes that cannot be removed from the process liquid by conventional separating devices or only to an inadequate extent. Finally, production and treatment in currently known methods for treating products and containers in which the process liquid is at least partially recirculated must be interrupted at relatively short intervals to clean and sterilise the treatment device. Such cleaning and sterilisation processes are typically very laborious and in particular lead to production losses and as a consequence to financial losses.
It is therefore the aim of the invention to develop an improved method and an improved device that can eliminate the deficits still existing in the prior art. In particular, in comparison to the prior art an improved method and improved device for treating products, especially food products, and/or containers is to be provided, in which method or device the process liquid can be at least partially recirculated for re-use in the method, but the disadvantages associated with this due to continuously increasing dirtying or contamination of the process liquid are avoided as much as possible.
The aim of the invention is achieved by providing a method for treating foods and containers for holding foods using a process liquid in at least one treatment zone, in which method at least one membrane filtration system and at least one UV irradiation apparatus are provided for continuous cleaning and sterilisation of the process liquid.
The foods and the containers are introduced into a treatment zone or conveyed through a treatment zone. At least one liquid stream of the process liquid is conducted into the treatment zone or treatment zones to act on the foods or containers, and discharged from the treatment zone again after completed treatment of the food products and containers, wherein the process liquid for treating the foods and containers is at least partially recirculated into the treatment zone or the treatment zones for the purpose of re-use in the method.
In particular, in the continuous, ongoing treatment, at least some or all of the process liquid out of the total process liquid conducted through all existing treatment zones per time unit is used in each time unit to form at least one stream of the process liquid, and the at least one resulting stream of the process liquid is filtered by at least one membrane filtration system and/or irradiated by at least one UV irradiation apparatus in order to clean and sterilise the process liquid, and after the filtration process an irradiated and/or filtered stream is at least partially returned to an element holding or conducting the process liquid and/or to a treatment zone.
Here and below, an element holding or conducting the process liquid or a conduction element for the process liquid means any element that is designed to hold the process liquid or to conduct a liquid stream of the process liquid. These can be, for example, piping, ducts, and the like in which the process liquid is e.g. fed into a treatment zone or discharged from a treatment zone. The term “conduction element” further means, for example but not exclusively reservoirs, tanks, or collection devices for the process liquid arranged inside or outside the treatment zones or the like.
Here and below, a treatment zone means a zone in which the food is brought into contact with the process liquid, preferably indirectly, and/or the containers are brought into contact with the process liquid, preferably directly. The physical and/or chemical and/or other parameters of the process liquid can be adjusted specifically for the relevant treatment purpose. The process liquid can affect the food and the containers for holding food in various ways. For example, to generate the desired interaction the process liquid and a liquid foodstuff to be treated can be conducted in a materially separated manner in a counter current, direct current, or cross flow arrangement in adjacent conduction elements. The desired interaction can be achieved by heat transfer between the food and the process liquid in the sense of a heat exchanger, as for example is usual in the pasteurisation of milk for preservation. Another frequently used method is the pasteurisation of food products in which the food is already in a closed container and the process liquid acts on the outside of the containers. The process liquid can be poured on the outside of the containers or the containers can be sprinkled or sprayed with the process liquid. In another example, dipping methods are also possible in which containers holding food are dipped into the process liquid. Naturally, however, the invented method and invented device can also be used for treatment, e.g. rinsing/cleaning of empty containers. Finally, the term treatment zone means, at least in the broadest sense, also an element holding or conducting the process liquid or a conduction element for the process liquid.
Here and below, a liquid stream of the process liquid means any kind of conducted movement of the process liquid, regardless of how the liquid stream or its conduction are designed. This means that the term “liquid stream” comprises; for example, a stream of a moved process liquid in conduction elements like piping, ducts, reservoirs, tanks, etc. just as much as, for example, a sprinkling or spray stream of the process liquid free falling under ambient air pressure in a treatment zone or a stream of the process liquid in a recooling apparatus or the like.
Through the measures disclosed in claim 1, a method can be prepared that is eminently suitable especially for the removal of impurities or contaminants with a very small particle size such as bacteria colonies from the process liquid and for sterilising the process liquid. This allows a significant improvement to be achieved compared to previously known methods, which are of only limited or even of no use in removing small particles as well as viable and reproducing micro-organisms from an at least partially recirculated process liquid. Advantageously, the cleaning and sterilisation of the process liquid can be performed during ongoing operation and is comparatively efficient and energy-saving.
Furthermore, the membrane filtration per se is effective at removing micro-organisms, as a result of which the combination of membrane filtration and UV irradiation acts in synergy to clearly increase the efficiency of a reduction of reproducing micro-organisms. If the membrane filtration is executed in the form of so-called “ultra-filtration,” i.e. filtration with membranes with pore diameters of approx. 0.2 □m or less, both inorganic and organic small and micro-particles, e.g. bacteria colonies, can be effectively removed from the process liquid.
In principle, a UV irradiation apparatus can be connected in series on the inlet side to a conduction element holding or conducting the process liquid, such as piping. In this case, the entire liquid stream of the process liquid flowing through this conduction element or piping is conducted through the UV irradiation apparatus and irradiated. The same fundamentally also applies to the connection of a membrane filtration system for filtering the process liquid.
Alternatively, a UV irradiation apparatus and/or a membrane filtration system can also be operatively connected parallel to a conduction element holding the process liquid so that a partial quantity of the process liquid out of the liquid stream of the process liquid can be used to form at least one stream of the process liquid per time unit. In this context is can also be advantageous if at least one adjustable splitting means or multiple co-operating splitting means are used to separate out a specifiable quantity of the process liquid from at least one element holding or conducting the process liquid in a controlled manner per time unit and to form at least one stream of the process liquid which can then be irradiated and/or filtered. In this way the partial quantity of process liquid separated out from a liquid stream of the process liquid per time unit can be specified and controlled in a precise manner. It is also advantageous that the partial quantity of process liquid separated out per time unit can be adjusted to the current conditions and varied. In this way capacity bottlenecks can be avoided without having to accept significant compromises on degree of contamination or germ content of the process liquid.
The exact number, type, and location of integration of the membrane filtration system(s) and UV irradiation apparatus(es) and the connection of a membrane filtration system and a UV irradiation apparatus to the conduction elements conducting the process liquid and/or treatment zone(s) can be determined or implemented in due consideration of structural features, process parameters, and the like. However, specific arrangement variations can offer advantages for the method for treating food and containers, which will be explained in more detail below.
For example, additional dirt traps or the like can be arranged in the conduction elements to remove large-grained impurities in the process liquid. For example, a gravitational sedimentation device as described in the previously cited EP 2 722 089 A1 can be used to separate large or large-grained particles.
The measures disclosed in claim 1 further succeed in reducing as much as possible laborious and expensive interruptions in the production or treatment in order to clean the treatment device or at least in significantly lengthening the time intervals between such cleaning processes. In addition, micro- and ultrafiltration and UV irradiation can at least reduce the quantity of chemical stabilisers used to prepare the process liquid, especially the required quantities of surfactants and corrosion inhibitors, and of disinfectants and biocides, and the use of such cleaning chemicals and disinfection chemicals can be at least largely avoided or minimised. Membrane filtration is effective at removing both micro-organisms and other impurities. UV irradiation further increases the efficiency of the method in regard to sterilisation. Membrane filtration can also markedly improve the effectiveness and efficiency of the UV irradiation apparatus(es). Small and micro-particles and suspended solids can cause turbidity of the process liquid, which can significantly reduce the effectiveness of the UV irradiation. A membrane filtration system can significantly reduce the turbidity of the process liquid and therefore avoid efficiency losses in UV irradiation due to UV light absorption, scattering, etc. The turbidity of a liquid can be expressed in, for example, the unit NTU (nephelometric turbidity unit). The process liquid preferably has a turbidity of less than 5 NTU, especially less than 1 NTU.
Small and micro-particles and substances that cause turbidity can be caused, among other ways, in the course of manufacturing the containers by shaping or cutting process steps such as cutting, milling, drilling or the like and/or can get into the process liquid through the containers. In typical devices for treating foods and/or containers, the formation of small and micro-particles is particularly facilitated by the use of chemicals like surfactants.
Thus a significant improvement in environmental friendliness can be achieved and the burden on a facility, such as a purification plant, placed after the method or device can be minimised. In addition, irradiation by UV light is also effective at suppressing the reproduction of at least most types of algae.
The invented measures can also improve olfactory factors as the formation of undesirable or unpleasant smells can be hindered. Various micro-organisms, especially bacteria, are known for generating bad smells as products of their metabolism. The removal or killing of these micro-organisms can largely prevent unpleasant smells.
If bacterial cultures remain in a process liquid for a longer time under simultaneous use of biocides, bacterial strains can “get used to” the biocides being used or bacterial strains resistant to the biocides being used can be formed. This means that biocides can become of limited or even no use in removing micro-organisms from the process liquid over time. Through continuous removal of the micro-organisms from the process liquid and additional UV irradiation of the process liquid, the formation of resistant germs can be hindered and the use of biocides can be minimised overall as efficient and effective means are provided to hinder the growth and reproduction of micro-organisms in the process liquid. Membrane filtration and UV irradiation can, for example, also effectively hinder the growth of biocide-resistant and/or chlorine-resistant bacterial strains.
Naturally other organic and inorganic small and micro-particles can also be removed from the process liquid by the at least one membrane filtration system. This simultaneously results in further improvement in regard to micro-organism growth and to the growth rate of micro-organisms in the process liquid, as organic and inorganic small and micro-particles can often act as good nutritional bases or “breeding grounds,” e.g. for bacteria. The removal of unwanted particle contaminants using membrane filtration can significantly reduce the use of otherwise necessary chemicals for elimination of such contaminants, such as surfactants.
The invented measures can also remove dust-like impurities from the process liquid. Such impurities can, for example, be caused in the course of manufacturing the containers by shaping or cutting process steps like cutting, milling, drilling or the like. The manufacturing of containers can cause e.g. glass of metal dust, especially aluminium dust, which dust can be introduced into the method for treating foods and containers along with the containers.
Finally, the invented measures can effectively hinder dirtying or contamination by germs of the outside of the containers as well as the surfaces of the device for treating the foods and containers by the process liquid itself. This brings further advantages in regard to any secondary treatment or additional cleaning measures, whose extent can at least be reduced. Where appropriate, the invented measures can make secondary cleaning of the containers with cleaning and disinfecting chemicals and/or sterilisation of the containers superfluous.
The additional measure of filling the food to be treated into containers before the treatment, closing the containers, tempering a liquid stream of the process liquid before feeding it into a treatment zone, and treating the foods in a treatment zone through heat transfer using a tempered process liquid in which the process liquid flows around the outside of the containers on the one hand represents a particularly efficient measure for treating foods, since an already filled trade product can be put out after the treatment. In addition, this allows direct contact between the foods and the process liquid to be avoided.
It can further be advisable to set the temperatures of the particular liquid streams of the process liquid separately for each treatment zone in a controlled manner before feeding into a treatment zone and to pasteurise the food products in at least one treatment zone using a heated process liquid. Pasteurisation can achieve a longer shelf life for the foods. The disclosed measures for controlled tempering of the process liquid have the advantage that the overall method for treating the foods and containers is easy to control. In particular, this can prevent unwanted damage to the foods and/or containers because of overly quick or high temperature changes.
It can be useful especially in regard to pasteurisation of food to successively heat up the foods being treated, especially luxury food products, in at least one treatment zone, to pasteurise them in at least one treatment zone, and to cool them in at least one treatment. On the one hand, slow heating in at least one heating zone can guarantee gentle heating of the foods. On the other hand, active cooling in at least one cooling zone after pasteurisation can effectively prevent so-called “over-pasteurisation” because of foods being at a high temperature for too long of a time. Such over-pasteurisation often caused unwanted changes in the food and can negatively influence the flavour and/or smell of the food. The disclosed process steps for sequential treatment of foodstuffs, especially luxury food products, allows well-controlled and gentle process guidance for the foodstuffs. For example, the temperature of the process liquid can be increased step by step for multiple heating zones, in one or more treatment zones the process liquid can be introduced at a pasteurising temperature such as 80 to 85° C. and then the process liquid can be introduced into one or more cooling zones for the foodstuffs or containers, again in the form of zones, with sequentially lower temperatures for cooling the foods or containers.
Alternatively to the stated temperature ranges, which are given as examples for the pasteurisation of food, other temperature ranges can of course also be advisable for other treatment processes. Another example given at this juncture is superheated steam sterilisation, in which the process liquid or process water reaches temperatures above 100° C. such that at least in the sterilisation zones process water acts on the containers in a gaseous state.
It has proven particularly practical if a liquid stream is fed into at least one treatment zone for heating the foods and/or containers at a temperature between 40° C. and 50° C. This provides particularly gentle pre-heating of the food and allows large temperature jumps to be avoided in the course of heating the food.
In an advantageous embodiment of the method, it can be provided that at least one stream filtered by a membrane filtration system is fed into a UV irradiation apparatus and irradiated immediately after the filtration process and a filtered and irradiated stream of the process liquid is fed back into at least one conduction element holding and/or conducting the process liquid and/or at least one treatment zone. In this way it can be ensured that a process liquid with particularly low turbidity can be irradiated by the UV irradiation apparatus, allowing the efficiency of the UV irradiation to be increased once more.
In order to prepare a process liquid with low turbidity, it can also be practical if process liquid with a temperature between 40° C. and 50° C. is used to form at least one stream to be filtered. Particularly good filtration results can be achieved through membrane filtration or ultrafiltration at a process liquid temperature in this range. This is because, among other reasons, blockage of filter membranes due to lubricants such as paraffin or waxes can be avoided in this temperature range. Such lubricants are often used during manufacturing of containers, sometimes remain stuck to the containers after manufacturing, and can be introduced into the process liquid. Through membrane filtration of the process liquid in the stated temperature range, process liquid with particularly low turbidity can be prepared for UV irradiation.
In this connection it can also be provided that the at least one stream be formed by removing process liquid from a tempering-capable flow container for the process liquid. This can increase the efficiency of the membrane filtration and the filtration performance even more.
In regard to cleaning efficiency for the process liquid during continuous treatment, it can be advisable to select the process liquid quantities used to form at least one stream of the process liquid out of at least one conduction element holding and/or conducting the process liquid during continuous treatment per time unit in such a way that the irradiation and/or filtration of the stream or streams allow a removal rate for micro-organisms to be achieved that is larger than the growth rate of these micro-organisms in the process liquid in the same time unit. This in particular allows the total quantity of viable and reproducing micro-organisms in the process liquid to be minimised as much as possible and an increase in the total quantity of micro-organisms in the process liquid during continuous treatment of the foods and/or containers to be effectively prevented.
Surprisingly, it has been shown that the irradiation and membrane filtration per time unit of a relatively small partial quantity of the process liquid out of the total liquid streams of the process liquid conducted through the device and/or the treatment zones per time unit is entirely sufficient to achieve an adequate result. This means that the physical size and/or the number of UV irradiation apparatus(es) and membrane filtration system(s) can be kept comparatively small without having to compromise on the degree of contamination and germ content or bacterial count of the process liquid. In addition, the amount of energy used to clean and sterilise the process liquid can be further reduced.
By recirculating a UV-irradiated and/or micro- or ultrafiltered stream of the process liquid at ambient pressure or in free fall back into at least one conduction element holding or conducting the process liquid and/or into one treatment zone, the advantage is obtained that an additional conveying means for introducing or discharging an irradiated and/or filtered stream into the process liquid is not needed.
It can be advisable here for an irradiated and/or filtered stream of the process liquid to be at least partially fed into a liquid stream of the process liquid moved through a treatment zone after it acts on the foods or containers. This variation of feeding a filtered stream into a treatment zone is advantageous in particular if a liquid stream of the process liquid is introduced into the treatment zone under a certain pre-existing pressure. The pre-existing pressure may be needed, for example to atomise the process liquid in order to spray the containers as evenly as possible in the treatment zone. This variation on introducing a filtered and/or irradiated stream is also advisable, for example, to avoid unwanted influence of the filtered and/or irradiated stream on the foods and containers in the treatment zone. This may happen, for example, because of an unsuitable temperature level of the filtered and/or irradiated stream of the process liquid.
However, it can also be advisable for an irradiated and/or filtered stream of the process liquid to be at least partially fed into a liquid stream of the process liquid moved through a treatment zone before it acts on the foods or containers. This in particular allows a process liquid with very high purity and very low germ content to be provided for treating the foods and containers in a treatment zone.
In the method for treating foods and containers, at least partial feeding of an irradiated and/or filtered stream of the process liquid into a treatment zone arranged at the end of the process to receive the products can be particularly advantageous in order to rinse or clean the outside of the closed containers filled with food product. Such a process step is typically performed near the end of a method for treating foods and containers, then a drying step or other secondary treatment step may potentially still follow. In such a process step for rinsing and washing containers, dirtying and contamination of the process liquid are particularly critical because under some circumstances dirt and germ residues like bacteria or bacterial residues can remain on the surface of the container. This is why feeding a stream that has been UV irradiated and/or filtered and cleaned by a membrane filtration system into such a treatment zone for rinsing containers is advantageous.
In regard to the membrane filtration, it can further be advisable for a stream of the process liquid to be fed into a receiving container after filtration by the membrane filtration system and recirculated back into at least one element holding or conducting the process liquid and/or into a treatment zone and/or into a UV irradiation apparatus via an outlet or equivalent element arranged on the receiving container. In this way a reservoir of process liquid with high purity is collected or prepared that can be used for various purposes.
For example, a practical use for the process liquid filtrate collected in a receiving container can be achieved on one variation of an embodiment of the method by operatively separating a membrane filtration system from the rest of the device for treating foods and/or containers at specifiable time intervals during ongoing operation to clean the filter membranes and by feeding the process liquid filtrate collected in the receiving container through a membrane filtration system by reversing the flow direction through the filter membranes in comparison to filtration, i.e. the membrane filtration system is also cleaned by backflushing the filtrate. During continuous filtration of partial streams of the process liquid, residues naturally form on the filter membranes and modules over time. Particularly small particles can also penetrate into a filter membrane or a pore channel of a filter membrane and remain there. Overall, residues on the membrane surface and/or particles or substances that have penetrated into and remained in a membrane lead to blockages on and in a membrane and therefore to shrinking flow capability and a reduction of the filtration performance of a filter membrane. The disclosed periodic cleaning of the filter membrane module by the collected process liquid filtrate achieved by reversing the flow direction can prevent blockages and closure of membrane pores as much as possible. Backflushing can be additionally assisted by inputting gas, for example by inputting compressed air into a filter membrane module.
Contaminated liquid waste is formed in the course of cleaning by reversing the flow direction through the filter membranes of the membrane filtration system. It can be useful to discharge this liquid waste directly from the device for treating foods and containers and replace it with a corresponding quantity of fresh process liquid.
In connection with the cleaning of the filter membranes of a membrane filtration system by backflushing it can also be advisable to arrange a UV irradiation apparatus between a membrane filtration system and a receiving container. This permits UV irradiation of the process liquid collected in the receiving container during a backflushing/cleaning process for a membrane filtration system and allows a backflushing liquid with particularly low germ content to be used for backflushing the filter membranes. Alternately, the filter membranes of a membrane filtration system can also be backflushed using an externally added rinsing liquid, for example rinsing chemical-containing washing water or drinking water.
In regard to a membrane filtration system, it can also be advantageous to admix chemicals from one or more chemical sources using a dispensing device into a stream of the process liquid to be filtered or a filtered stream or a process liquid collected in a receiving container if needed both in treatment and in filtration and in cleaning for the membrane filtration system. If the dispensing device is suitably arranged, for example in a draining element for a filtered stream of the process liquid or a bypass or backflush piping linked to the draining element, admixing from the same chemical sources can take place both in treatment and in cleaning for the membrane filtration system. The type of chemicals to be used depends on the particular need and the feeding of chemicals can be performed by an operator of the device, or an automatic control device for the device as needed. Since the addition of chemicals is possible in both filtration and cleaning, a flexible, targeted dispensation of chemicals from the same chemical sources can be performed as needed. Examples of chemicals that are suitable for both cases are surfactants for general cleaning or chlorine for disinfection of the filter membranes or other elements of the device for treating foods and containers. Other typically used chemicals include, for example, organic acids for pH value stabilisation, chelating agents, and corrosion inhibitors.
In addition to preparing the process liquid through UV irradiation and membrane filtration, it can be useful to remove or separate dissolved or suspended or dispersed substances through an adsorption device. In particular, in this way unwanted, uncoagulated parts can be removed from the process liquid that cannot be removed by a membrane filtration system.
To ensure the greatest possible process security, it can be advantageous to continuously monitor the degree of contamination of the process liquid using suitable sensors arranged in the conduction elements holding and/or conducting process liquid and/or in the treatment zones. In particular, measurements of turbidity can be useful to determine the purity of the process liquid and the particle concentration in the process liquid. Measuring the turbidity of the process liquid is above all important in regard to assessing the efficiency of the UV irradiation, since turbidity of the process liquid can markedly decrease the effectiveness of UV irradiation, as has already been explained above. Alternatively and/or additionally, measurements on random samples of the process liquid are also useful, especially to record fluctuations in the content of bacterial cultures and determine micro-organism growth rates. Through continuous monitoring of the turbidity of the process liquid at different points or in different zones, sources of contamination can also be localised and targeted counter-measures can be introduced if needed.
Another advantage arises in a design variation in which a stream of the process liquid to be irradiated and/or filtered is formed as needed out of different conduction elements containing or conducting process liquid, is filtered by at least one membrane filtration system, and after the membrane filtration process a filtered stream is fed into at least one conduction element holding or conducting process liquid and/or at least one treatment zone and/or at least one UV irradiation apparatus. It can particularly be advantageous to integrate a membrane filtration system into the device for treating products and/or containers using mechanical switching and/or splitting means in such a way that a membrane filtration system can be assigned different and/or multiple different conduction elements for holding or conducting the process liquid and/or treatment zones. The possibility of inlet-side switching of a membrane filtration system to different sources of process liquid for forming a stream to be filtered allows quick and efficient reactions to zone-specific fluctuations in the quality and degree of contamination of the process liquid in a flexible manner, especially to fluctuations in the particle concentration. This way there exists a fundamental option of switching from one process liquid source to another process liquid source, i.e. of using different liquid streams in different conduction elements to form the stream to be filtered. If desired, however, multiple liquid streams of the process liquid can also be used simultaneously to form a stream of the process liquid to be filtered. In this case, the stream to be filtered is formed by mixing the used/removed partial quantities from the different liquid streams of the process liquid.
Also practical is a variation of the embodiment in which the stream of the process liquid is formed for filtration by a membrane filtration system by switching between or mixing of different liquid streams of the process liquid from different conduction elements depending on measured values obtained by in-line measurements and/or random sample measurements. It can also be advantageous to recirculate a filtered stream of the process liquid into different conduction elements or treatment zones and/or feed it into a UV irradiation apparatus, depending on measured values obtained by in-line measurements and/or random sample measurements, by feeding or distributing the filtered stream of the process liquid into different liquid streams of the process liquid.
However, the aim of the invention is also achieved by providing a device for treating foods and/or treating containers for holding foods using a process liquid.
The device comprises at least one treatment zone for treating the foods and/or the containers, a means of transport for transporting the foods and/or containers through the treatment zone(s), and conduction elements holding and/or conducting process liquid for feeding liquid streams of the process liquid into a treatment zone and conduction elements for discharging liquid streams of the process liquid out of a treatment zone. The device further comprises additional conduction elements for holding and/or conducting the process liquid in the device and at least one conveying means for conveying liquid streams of the process liquid in the conduction elements, wherein the conduction elements are designed and arranged such that the process liquid for treating the foodstuffs can be at least partially recirculated back into the treatment zone or into the treatment zones.
In particular, the device comprises at least one UV irradiation apparatus and at least one membrane filtration system for cleaning and sterilisation of the process liquid by membrane filtration and UV irradiation. The at least one UV irradiation apparatus and the at least one membrane filtration system are operatively connected to the conduction elements and/or to the treatment zones such that at least some or all of the total process liquid conducted through all existing treatment zones per time unit is used to form at least one stream of the process liquid, the resulting stream or resulting streams are filtered by the at least one membrane filtration system and/or irradiated by the at least one UV irradiation apparatus and a filtered and/or irradiated stream of the process liquid can be fed into at least one conduction element and/or at least one treatment zone.
Such a device is particularly suitable for the cleaning and sterilisation of the process liquid. This allows a significant improvement to be achieved compared to previously known devices, which are of only limited or even of no use in removing small and micro-particles as well as viable and reproducing micro-organisms and germs from an at least partially recirculated process liquid. Cleaning and sterilisation using the UV irradiation apparatus(es) and the membrane filtration system(s) can advantageously be performed during ongoing treatment and is also comparatively efficient and energy-saving.
The additional preparation and cleaning of the process liquid by a membrane filtration system can markedly increase the effectiveness and efficiency of the UV irradiation apparatus(es), as the turbidity of the process liquid can be markedly reduced, preventing efficiency losses in the UV irradiation caused by UV light absorption, scattering, etc. Furthermore, a membrane filtration system per se is effective at removing micro-organisms, as a result of which the combination of membrane filtration and UV irradiation acts in synergy to clearly increase the efficiency of a reduction of reproducing micro-organisms. Particularly when so-called “ultrafiltration systems” are used, i.e. membrane filtration systems with filter membranes with pore diameters of approx. 0.2 □m or smaller, both inorganic and organic small and micro-particles, e.g. including bacteria colonies, can be effectively removed from the process liquid.
Both a UV irradiation apparatus and a membrane filtration system can in principle be connected on the inlet side both in series and in parallel with a conduction element holding or conducting the process liquid. In cases of a parallel connection, it can be an advantage to arrange at least one adjustable splitting means and/or multiple co-operating splitting means on the inlet side of a UV irradiation apparatus and/or a membrane filtration system for controlled removal of a specifiable process liquid quantity per time unit out of at least one conduction element holding or conducting the process liquid and for formation of a stream of process liquid to be irradiated and/or filtered. This design feature allows the partial quantity removed from a liquid stream of the process liquid per time unit to be controlled very precisely and adjusted to the particular immediate conditions.
Other advantages arising from the characteristics of the device have already been explained in more detail above in the description of the method that can be executed by the device, and a repeated explanation can be omitted at this point.
In a practical further development of the device, it comprises at least one heating means for heating the process liquid and one cooling means for cooling the process liquid. As a result of this, appropriately tempered liquid streams of the process liquid can be used to purposefully heat and cool the foods and containers.
The further characteristic that at least one treatment zone is designed for application of the process liquid on the outside of closed containers, wherein the process liquid flows around the outside of a closed container, is a particularly efficient construction characteristic for treating foodstuffs, since an already finished and filled trade product can be put out after the treatment. In addition, in this way the risk of recontamination of the foodstuffs in a filling zone placed after the treatment zone(s) can be precluded and/or a filling zone placed after the treatment zones is made superfluous.
In addition, it can be an advantage to arrange at least one treatment zone for heating the foods and/or containers, at least one treatment zone for pasteurising the foods, and at least one treatment zone for cooling the foods and/or containers in succession along the direction of transport of the foods or containers. This design can provide a device for treating foods and containers in which the food can be pasteurised particularly gently and damage to the pasteurised foods can be effectively prevented.
In an advantageous design variation it can be provided that at least one UV irradiation apparatus be operatively arranged immediately after a membrane filtration system such that a filtered stream of the process liquid can be irradiated by a UV irradiation apparatus immediately after membrane filtration. This can further increase the efficiency of the UV irradiation as a process liquid with particularly low turbidity can be prepared for the UV irradiation.
It can further be provided that a feeding element of a membrane filtration system be connected to a tempering-capable flow container for the process liquid. This way the temperature of a stream of process liquid to be filtered can be purposefully set and the filtration efficiency optimised.
It can further be advisable to design the device in such a way that the number and irradiation power of the UV irradiation apparatus(es) and the number and filtration capacity of the membrane filtration system(s) are fixed such that the total process liquid quantity drawn out of at least one element containing and/or conducting the process liquid per time unit for forming at least one stream of the process liquid during continuous treatment can be chosen such that the filtration and irradiation of the stream or the streams can achieve a removal rate of micro-organisms that is greater than the growth rate of the micro-organisms in the process liquid in the same time unit. These characteristics create a device in which the UV irradiation apparatus(es) and the membrane filtration system(s) can keep the total quantity of viable and reproducing micro-organisms in the process liquid as low as possible and an increase in the total quantity of micro-organisms in the process liquid during continuous treatment of the foods and/or containers is effectively prevented.
Another design of the device that can be advantageous is one in which, to recirculate an irradiated and/or filtered stream of the process liquid, draining elements out of at least one UV irradiation apparatus and/or out of at least one membrane filtration system are connected to at least one conduction element and/or at least one treatment zone in such a way that an irradiated and/or filtered stream of the process liquid can be fed into the conduction element(s) and/or the treatment zone(s) under the influence of gravity in free fall. This makes it possible for an additional conveying means for bringing in or away an irradiated and/or filtered stream of the process liquid to be made superfluous, resulting in a structurally simple to realise variation and an operationally efficient and cost-effective variation of the device.
For example, at least one UV irradiation apparatus and/or one membrane filtration system can be operatively connected on the inlet side to an opening in a treatment one such that an irradiated and/or filtered stream of the process liquid can flow off into the treatment zone. The opening in a treatment zone can be placed, for example, on an upper end of the treatment zone such that an irradiated and/or filtered stream of the process liquid can be at least partially fed into a liquid stream of the process liquid that is moved through a treatment zone before it acts on the foods and containers. On the other hand, however, it can also be practical to place such an opening at a lower end of the treatment zone to avoid unwanted, e.g. thermal influence of an irradiated and/or filtered stream on the foods and containers in the treatment zone.
Another advantageous design of the device can be provided by designing at least one treatment zone for rinsing the outside of closed containers filled with foodstuffs, which at least one treatment zone is placed at the end of the treatment zone line in the transport direction of the containers through the treatment zones and which is connected to at least one draining element of a UV irradiation apparatus and/or a draining element of a membrane filtration system in order to rinse the containers by feeding in an irradiated and/or filtered stream of the process liquid. This provides a treatment zone for the final cleaning of the outside of the containers using an irradiated and/or filtered stream of the process liquid in which the outside of the containers can be rinsed by a process liquid with very high purity and low germ content.
In regard to the membrane filtration system(s), a variation of the design in which a receiving container with an overflow is arranged in a draining element of a membrane filtration system can also be of advantage. This way a reservoir of process liquid can be collected and provided to be used for various purposes.
For the purposes of cleaning a membrane filtration system, it can for example be advisable to place closures in the feeding elements and draining elements to operatively separate the at least one membrane filtration system from the rest of the device and to place at least one conveying means in the receiving container and/or backflush piping stretching between the receiving container and the draining element of the membrane filtration system that is designed to transport the process liquid filtrate collected in the receiving container in the opposite direction—compared to the flow direction through the filter membranes during filtration—through the at least one membrane filtration system. In this way, a membrane filtration system can be cleaned through backflushing using the process liquid collected in the receiving containers during ongoing treatment by the device for treating the foods and containers. Thus e.g. blockages in a membrane and the closure of pores of a membrane can be prevented as much as possible without requiring an interruption of treatment by the device. When the filter membranes of a membrane filtration system are cleaned by backflushing, it can also be advisable to place a UV irradiation apparatus between a membrane filtration system and a receiving container. This permits UV irradiation of the process liquid collected in the receiving container during a backflushing/cleaning process for a membrane filtration system and allows a backflushing liquid with particularly low germ content to be used for backflushing the filter membranes.
It can further be practical to discharge the liquid waste accrued in the course of cleaning by reversing the flow direction through the filter membranes of the membrane filtration system, to assign at least one closable liquid waste line to the membrane filtration system, and to place at least one closable feed device in the device to replace the discharged liquid waste with fresh process liquid. This makes it possible to discharge the liquid waste directly from the device for treating foods and containers and replace it with a corresponding quantity of fresh process liquid.
It can also be useful to place a dispensing device in a draining element and/or in the backflush piping of the at least one membrane filtration system through which the process liquid or the process liquid collected in a receiving container can be admixed with chemicals from one or more chemical sources both during filtration and when cleaning the membrane filtration system. By installing a dispensing device connected to the chemical source(s), chemicals like chloride, surfactants, and other active chemicals can be admixed with the process liquid as needed both during filtration and when cleaning a membrane filtration system.
In addition to the inclusion of at least one UV irradiation apparatus and/or one membrane filtration device, a design of the device in which an adsorption device is included can be advantageous. In this way unwanted, uncoagulated parts can also be removed from the process liquid that cannot be removed by a membrane filtration system. For example, carbon compounds can be removed from the process liquid using activated charcoal in such an adsorption device.
For better process security, it can be useful to place sensors in conduction elements and/or in treatment zones for continuous monitoring of the degree of contamination, especially by measuring the turbidity of the process liquid. This way the degree of contamination of the process liquid can be recorded and continuously monitored at least in sections. Inclusion of such sensors is helpful for, among other things, evaluating the efficiency of the UV irradiation apparatus(es). Through continuous monitoring of the turbidity of the process liquid at different points or in different zones of the device for treating foods and/or containers, sources of contamination can also be localised and targeted counter-measures can be introduced if needed.
Another advantageous design can be formed by assigning at least one switching means to a feeding element of a membrane filtration system that is operatively connected to at least two different conduction elements holding the process fluid in such a way that the stream of process liquid to be filtered can be formed as desired either from one of the liquid streams or multiple liquid streams of the process liquid in the conduction elements or from multiple liquid streams of the process liquid. This allows the membrane filtration system to be switched on the inlet side to different sources of the process liquid to form a filtered stream. In this way, for example, quick and efficient reactions are possible to zone-specific fluctuations in quality and degree of contamination of the process liquid, especially to fluctuations in the particle concentration.
Another design that is of advantage can be formed by assigning at least one mixing means to a feeding element of a membrane filtration system that is operatively connected to at least two different conduction elements holding the process fluid in such a way that a stream of process liquid to be filtered can be formed as desired either from one of the liquid streams or multiple liquid streams of the process liquid in the conduction elements or a stream of the process liquid to be filtered by the membrane filtration system can be formed by removing and mixing specifiable partial quantities from multiple liquid streams of the process liquid. This allows simultaneous removal of partial quantities of process liquid from different conduction elements and the formation of a stream of the process liquid to be filtered by mixing the removed partial quantities of process liquid.
However, it can also be advisable to assign at least one switching means to a draining element of a membrane filtration system that is operatively connected to at least one conduction element holding process liquid and/or at least one treatment zone and/or a UV irradiation apparatus in such a way that feeding a filtered stream of the process liquid into the at least one conduction element and/or the at least one treatment zone and/or the irradiation apparatus can be controlled. In this way a filtered stream of the process liquid can be fed as needed into one or more conduction element(s) and/or one or more treatment zone(s) and/or one or more UV irradiation apparatuses. This can be practical, for example, to set specific temperatures in sections for the process liquid in the device for treating foods and containers.
However, another design variation can be of advantage in which at least one splitting means is assigned to a draining element of a membrane filtration system which is operatively connected to at least one conduction element holding the process liquid and/or at least one treatment zone and/or a UV irradiation apparatus in such a way that feeding a filtered stream of the process liquid into the at least one conduction element and/or the at least one treatment zone and/or the at least one UV irradiation apparatus can be controlled or specifiable quantities of the filtered stream of process liquid can be fed into the at least one conduction element and/or the at least one treatment zone and/or the at least one UV irradiation apparatus.
Finally, the aim of the invention is also achieved by using a membrane filtration system and a UV irradiation apparatus for continuous cleaning and sterilisation of a process liquid in a device for treating foods and containers for holding foods using the process liquid. This way the process liquid in the device for treating foods and containers for holding foods can be continuously cleaned and sterilised in a particularly efficient way.
To facilitate better understanding of the invention, it will be explained in detail using the figures below.

Extremely simplified, schematic depictions show the following:

FIG. 1 An example embodiment of a known device for treating foods and/or containers with treatment zones in an extremely simplified, schematic, and not-to-scale depiction:

FIG. 2 A P&ID diagram of an example embodiment of a device for treating foods and/or containers in an extremely simplified depiction:

FIG. 3 Excerpts of a partial diagram of an embodiment of a device with UV irradiation apparatus and membrane filtration system in an extremely simplified depiction;

FIG. 4 Excerpts of a partial diagram of an embodiment of a device with UV irradiation apparatus and membrane filtration system in an extremely simplified depiction;

FIG. 5 Excerpts of another partial diagram of an embodiment of a device with a UV irradiation apparatus and a membrane filtration system in an extremely simplified depiction;

FIG. 6 Excerpts of another partial diagram of an embodiment of a device with a UV irradiation apparatus and a membrane filtration system in an extremely simplified depiction;

FIG. 7 Excerpts of another partial diagram of an embodiment of a device with a UV irradiation apparatus and a membrane filtration system in an extremely simplified depiction;

FIG. 8 Excerpts of another partial diagram of an embodiment of a device with a UV irradiation apparatus and a membrane filtration system in an extremely simplified depiction;

FIG. 9 An example design of a membrane filtration system with subsequent UV irradiation apparatus, schematic and in an extremely simplified depiction;

FIG. 10 Excerpts of another partial diagram of an embodiment of a device with a UV irradiation apparatus and a membrane filtration system in an extremely simplified depiction;

FIG. 11 Excerpts of another partial diagram of an embodiment of a device with a UV irradiation apparatus and a membrane filtration system in an extremely simplified depiction.

In introduction, let it be noted that in the variously described embodiments, identical parts are provided with identical reference signs or identical part names, and that the disclosures contained in the description as a whole can be carried over analogously to identical parts with identical reference signs or identical part names. Likewise, positional information selected in the description, e.g. above, below, on the side, etc. refer to the directly described and depicted figure and if the position is changed, this positional information carries over analogously to the new position.
FIG. 1 shows an example of an arrangement of treatment zones of a device 1 for treating foods and/or treating containers 2 for holding foods in a schematic and extremely simplified depiction. The foods and containers 2 are treated by a process liquid 3 in at least one treatment zone 4. In the example embodiment shown in FIG. 1 the foodstuffs to be treated are located in closed containers 2 and are treated using a process liquid 3 by having a liquid stream 5 of the process liquid 3 flow around the outside 6 of the containers 2. In the example embodiment depicted in FIG. 1, the liquid stream 5 of the process liquid 3 through a treatment zone 4 is generated by the process liquid 3 being split by splitting devices such as spray nozzles 7 on the top of the treatment zone 4 and the liquid stream 5 of the process liquid 3 traversing the treatment zones 4 from top to bottom. A liquid stream 5 of the process liquid 3 is fed into a treatment zone 4 using structurally suitable conduction elements 8 like piping connected to the spray nozzles 7. In an analogous manner, after passing through a treatment zone 4 a liquid stream 5 of the process liquid 3 is removed from a treatment zone 4 again by means of other conduction elements 8 assigned to the bottom of a treatment zone 4. The conduction elements 8 provided to drain a liquid stream 5 of the process liquid 3 out of a treatment zone 4 can be formed by, for example, collecting tubs 9 that collect the liquid stream 5 of the process liquid 3 sprinkling through a treatment zone 4 at the bottom of the treatment zone 4. The process liquid 3 caught by the collecting tubs 8, 9 can then be discharged out of a treatment zone 4 by conduction elements 8 or piping 8 connected to the collecting tubs 8, 9, as shown schematically in FIG. 1.
The containers 2 can be transported through the treatment zones 4 using suitable means of transport 10 such as conveying means belts or the like, e.g. on two levels from left to right as shown in FIG. 1 by the arrows 26 depicting a transport direction 26 for the containers 2.
Alternately to the embodiment shown in FIG. 1, a treatment zone for treating the foods using a process liquid can naturally be created in other ways as well. For example, a treatment zone for treating a liquid foodstuff can be designed as a heat exchanger in which the liquid foodstuff and the process liquid are conducted past each other while materially separated, as is for example typical when pasteurising milk. The description of the invented device 1 using the embodiment shown in FIG. 1 is continued below, though it is noted at this juncture that the invention is not limited to the example embodiments specifically depicted below but also comprises alternative designs.
In the example embodiment shown in FIG. 1, the two treatment zones 4 depicted on the left side in FIG. 1 can be used e.g. for successive heating of the containers 2 or the foods found in the containers. The treatment zone 4 depicted in the middle of FIG. 1 can be used e.g. for pasteurising foods and the two treatment zones 4 depicted on the right side in FIG. 1 can be used for sequential cooling of the foods and containers. The corresponding treatment steps for heating, pasteurising, and cooling can be executed by feeding a suitably tempered liquid stream 5 of the process liquid 3 in the relevant treatment zone 4. It can be practical for a liquid stream 5 to be fed into at least one treatment zone 4 for heating the foods and/or containers at a temperature between 40° C. and 50° C.
To feed a liquid stream 5 of the process liquid 3 into the relevant treatment zone 4, conveying means 11 can be assigned to the treatment zones 4 as can be seen in the flow diagram depicted in FIG. 2. To avoid unnecessary repetition, the same reference signs and part names will be used for the same parts in FIG. 2 as in the preceding FIG. 1, with only three treatment zones 4 being depicted in FIG. 2 for greater clarity. The treatment zone 4 depicted in FIG. 2 left can again be used, for example, for heating the containers or foods, while the treatment zone 4 drawn in FIG. 2 middle can be provided for pasteurisation and the treatment zone 4 drawn in FIG. 2 right can be provided for cooling the containers and foods.
The example embodiment of a flow diagram of a device 1 shown in FIG. 2 comprises a heating means 12 for heating the process liquid 3 and a cooling means 13 for cooling the process liquid 3. In the case of the example embodiment shown in FIG. 2, the process liquid 3 is fed into and/or conducted through the heating means 12 by an additional conveying means 11 out of a conduction element 8 in the form of a liquid tank 14 via conduction elements 8 in the form of piping or the like. The process liquid 3 in the heating means 12 can be heated in a great variety of ways, for example by heat transfer to the process liquid through a heating medium, for example saturated steam. In principle, any source of heat can be used to heat the process liquid 3, though it can be practical for pasteurising food for the heating means 12 for heating the process liquid 3 to be set to a temperature of at least 80° C. After running through the heating means 12, the liquid stream 5 of the process liquid 3 heated in this way can be fed into the treatment zones 4 through conduction elements 8, e.g. piping.
Other methods for treating the foods and containers are also conceivable alternately or additionally to the example embodiments shown in FIG. 1 and FIG. 2. For example, a process liquid, especially process water for treating foods and/or containers can also be heated above the boiling point of the process water, so to a temperature above 100° C., and fed into a treatment zone as superheated steam. This may be practical for purposes of e.g. sterilisation. In another example, dipping methods are also possible in which containers holding food are dipped into the process liquid.
To cool the process liquid 3, the process liquid 3 can be fed into the cooling means 13 as shown in FIG. 2, for example out of a liquid tank 15. In the example embodiment shown in FIG. 2, the cooling means 13 is connected to the liquid tank, for example a cold water tank 15, by conduction elements 8 in such a way that a liquid stream 5 of the process liquid 3 can be removed by a conveying means 11 from the liquid tank 15 and returned to the liquid tank 15 after completed cooling of the liquid stream 5 of the process liquid 3. The cooling means 13 can, for example, be executed as a cooling tower or heat exchanger in which the process liquid 3 is cooled by air or another cooling medium flowing in the opposite direction.
As can further be seen from FIG. 2, the conduction elements 8 for holding and conducting the process liquid 3 or the liquid streams 5 of the process liquid 3 in the device 1 are designed or arranged such that the process liquid 3 can be at least partially recirculated into the treatment zones 4 again. For better clarity, the flow directions for the liquid streams 5 of the process liquid 3 for the treatment mode of device 1 are indicated in FIG. 2 by arrows. Closable emptying devices 16 are provided to discharge a partial quantity of the process liquid 3 and at least one closable conduction element 8 designed as a feeding device 17 is arranged to feed in fresh process liquid 3. In the example embodiment shown in FIG. 2, flow regulator apparatuses 18 are provided in the conduction elements 8 placed on the inlet side of the treatment zones 4, by which flow regulator apparatuses 18 the liquid streams 5 of the process liquid 3 can be mixed at different temperature levels in a controlled manner. This makes it possible to purposefully set the temperature of the liquid streams 5 of the process liquid 3 separately for each treatment zone 4. In place of the depicted flow regulator apparatuses 18, three-way mixing valves or other suitable means can be provided for controlled mixing and setting of the temperature of a liquid stream 5 of the process liquid 3.
Of course, the example embodiment shown in FIG. 2 only shows one design of a device 1 for treating products and containers. For example, for some embodiments of devices for treating foods and/or containers it is typical to feed a liquid stream directly into another treatment zone after it is drained from one treatment zone. This is useful, for example, if a liquid stream of the process liquid drained out of a treatment zone has a temperature level suitable for treating the foods and/or containers in another treatment zone. Such alternative or supplementary designs to the example embodiment shown in FIG. 2 can be executed as needed by a person with skill in the relevant art or are sufficiently known from the prior art that the presentation of further example embodiments at this juncture can be omitted.
FIG. 3 shows excerpts of a diagram of a device 1 for treating foods and/or containers, wherein at least one membrane filtration system 19 and at least one UV irradiation apparatus 47 are provided in the device 1 for cleaning and sterilisation of the process liquid. FIG. 3 uses the same reference signs and part names for the same parts as were used in the preceding FIGS. 1 and 2. To avoid unnecessary repetition, please refer to the detailed description in the above FIG. 1, 2.
The UV irradiation apparatus 47 and the membrane filtration system 19 shown as examples in FIG. 3 are operatively connected to the conduction elements 8 and/or to the treatment zones 4 such that at least some or all of the total process liquid conducted through all existing treatment zones 4 per time unit is used to form at least one stream 20, 20 of the process liquid to be filtered and/or irradiated, the resulting stream 20 or resulting streams 20 are filtered by the at least one membrane filtration system 19 and/or irradiated by the at least one UV irradiation apparatus 17 and a filtered and/or irradiated stream 46, 48 of the process liquid can be at least partially fed into a conduction element 8 and/or a treatment zone 4. Forming a stream to be filtered and/or irradiated by using the total quantity of process liquid circulated through one or more treatment zone(s) can above all be practical in small-sized devices for treating foods and/or containers.
In principle, any given liquid stream 5 of the process liquid can be used to form a stream 20 of the process liquid to be filtered and/or irradiated and/or partial quantities of the process liquid can be taken from any liquid stream 5 to form a stream 20. Likewise, a filtered and/or conducted stream 46, 48 of the process liquid can in principle be returned to any conduction element 8 for the process liquid and/or to any treatment zone 4. However, certain variations of incorporating one or more membrane filtration system(s) 19 and/or UV irradiation apparatus(es) 47 offer advantages that are explained in more detail below using additional example embodiments depicted in the figures.
In the excerpts of the example embodiment shown in FIG. 3, a formed stream 20 is fed into a membrane filtration system 19 (left in FIG. 3) and a formed stream 20 is fed into a UV irradiation apparatus 37 (right in FIG. 3).
The membrane filtration system 19 shown by way of example in FIG. 3 is placed bypass-like between a conduction element conducting a liquid stream 5 and a treatment zone 3. The UV irradiation apparatus 47 shown by way of example is placed bypass-like between two conduction elements 8. In the example embodiment shown in FIG. 3, a filtered stream 46 is fed into a treatment zone 4 and an irradiated stream 48 is fed into a conduction element 8. It would of course also be possible to feed a filtered stream into a conduction element 8 and an irradiated stream 48 into a treatment zone 4.
In the example embodiment shown in FIG. 3, suitable splitting means 21 are used to remove a partial quantity of a liquid stream 5 of the process liquid per time unit to form a stream 20 to be filtered or irradiated. For controlled removal of a partial quantity out of the liquid stream 5 to form a stream 20, something like a splitting means 21 in the form of a flow regulator apparatus 18 can be placed in a feeding element 22 into a membrane filtration system 19 or into a UV irradiation apparatus 47, as shown on the left in FIG. 3. Alternately; as shown for example on the right in FIG. 3, a three-way splitting valve 23 can also be used as a splitting means 21. An additional splitting means 21 in the form of a conveying means 11 or pump can be arranged to work together with a valve 18, 23 in order to allow controlled removal of a partial quantity of the process liquid out of the conduction element 8. Preferably, however, the placement of an additional conveying means 11 in a feeding element 22 of a UV irradiation apparatus 47 or a membrane filtration system 19 is omitted and, as shown on the left in FIG. 3, the removal of a partial quantity of the process liquid is accomplished using only one conveying means 11 placed in a conduction element 8 of the device 1.
The treatment zone 4 shown on the left in FIG. 3 can again, for example, be designed as a heating zone for the foods or containers, the treatment zone 4 shown in the middle of FIG. 3 can be for pasteurising the food, and the treatment zone 4 shown on the right in FIG. 3 can be for cooling the foods or containers. Accordingly, during ongoing treatment mode of the device 1 the pasteurisation zone 4 placed in the middle would be fed a liquid stream 5 of a high-temperature process liquid, while the treatment zones 4 for heating and cooling the foods and containers would be fed liquid streams 5 at comparably low temperatures.
As indicated in FIG. 3, in order to spare the membrane filtration system 19 a liquid stream 5 at a relatively low temperature can be used to form a stream 20 of the process liquid to be filtered. In the example embodiment shown in FIG. 3, feeding elements 22 of the depicted membrane filtration system 19 are operatively connected to the conduction elements 8 leading to the heating treatment zone, i.e. the treatment zone 4 depicted on the left in FIG. 3. These conduction elements 8 hold a liquid stream 5 of relatively low-temperature process liquid. It is preferable for the at least one membrane filtration system for forming a stream 20 of the process liquid to be filtered to be operatively connected to locations with conduction elements 8 of the device 1 in such a way as to ensure that process liquids with a temperature between 40° C. and 50° C. are used to form at least one stream 20 to be filtered. As has been shown, membrane filtration and the filtration performance of a stream 20 of process liquid is particularly efficient in this temperature range.
As is further shown in FIG. 3, it can further be provided that a feeding element 22 of a membrane filtration system 19 be connected to a tempering-capable flow container 50 for the process liquid. Such a flow container 50 can, for example, be designed as a buffer with integrated heat exchanger or as a buffer with electric heating, etc. In this way a stream 20 can be formed by removing the process liquid from the tempering-capable flow container 50 for the process liquid.
Alternatively to the example embodiment shown in FIG. 3, an entire liquid stream 5 of the process liquid can be used to form a stream 20 of the process liquid, as is shown schematically in FIG. 4. In the example shown in FIG. 4, a membrane filtration system 19 and a UV irradiation apparatus 47 are operatively arranged serially in a conduction element 9 leading to a treatment zone 4. This way the entire liquid stream 5 of the process liquid 3 conducted through the conduction element 8 is directed through the depicted membrane filtration system 19 and the depicted UV irradiation apparatus 47 and in the example shown in FIG. 4 fed into a treatment zone 4 after completed membrane filtration and UV irradiation. As shown in FIG. 4, in such an arrangement providing an additional conveying means 11 to bring the process liquid 3 into a treatment zone 4 after completed membrane filtration and UV irradiation can be necessary because of the loss of pressure over the membrane filtration system 19 and the UV irradiation apparatus 47.
A UV irradiation apparatus suitable for executing the method or for use in the device can in principle be designed in a variety of ways. It is presupposed as generally known that UV irradiation apparatuses with radiation sources that radiate or consist of UV light with a wavelength equal to or smaller than 254 nm are particularly effective. In particular, this so-called UVC light breaks molecular bonds in the DNA of micro-organisms, killing the micro-organisms or at least converting them into a harmless, non-reproducing state. Mercury vapour lamps or amalgam lamps are often used as UVC radiation source(s).
It is preferable for UV irradiation apparatuses to be placed in the device that are intended to flow through the liquid to be irradiated and sterilised, i.e. that are designed as flow apparatuses. Such UV irradiation apparatuses can e.g. comprise a chemical-resistant sheath, made e.g. of rust-proof stainless steel, inside which the UVC radiation source(s) is placed. The sheath can have at least one feeding element and at least one draining element so that the liquid to be sterilised can be fed through the inside of the UV irradiation apparatus or the internal space defined by the sheath and irradiated. The radiation source(s), e.g. medium pressure mercury vapour lamp(s) can or could, for example, be placed in a quartz glass sleeve in the internal space of the UV irradiation apparatus defined by the sheath so that the liquid being irradiated flows around the radiation source(s). Alternately, it can also be provided that the liquid to be irradiated be conducted into the internal space of a UV irradiation apparatus in one or more UV-transparent conduit(s) and irradiated by the radiation source(s) from outside. These kinds of UV irradiation apparatuses are in principle known in the prior art.
It is important here for the irradiation power of a UV irradiation apparatus to be selected so that an effective, germ-reducing dose of the UVC radiation can be applied to the liquid to be irradiated. The effectiveness of a UV irradiation apparatus in regard to reducing germ content is directly dependent on the applied UV dose. The UV light dose is a product of the UV light intensity and irradiation time. Therefore the UV dose of a UV irradiation apparatus depends, among other things, on factors like the flow rate and speed of the liquid through the UV irradiation apparatus, UV translucence, and the turbidity of the liquid. When it comes to long-term effectiveness, however, the formation of deposits on the radiation source and decreasing radiation intensity with increasing lamp age must also be taken into account. It can therefore be practical for the UV irradiation apparatus to include monitoring devices that monitor the radiation output/intensity of the radiation source(s) so that a radiation source can be replaced if the radiation intensity is no longer sufficient.
In regard to the penetration depth of the UVC radiation into the liquid being irradiated, elements can for example be placed in the internal space of the sheath of a UV irradiation apparatus through which a stream conducted through the UV irradiation apparatus can be manipulated. For example, dividing a stream conducted through a UV irradiation apparatus can be useful or specially guiding it through redirecting elements in the internal space of the sheath of the UV irradiation apparatus. In addition, reflecting elements can be useful for better distribution of the UV radiation in the liquid flowing through.
FIG. 5 depicts another example embodiment of a device 1 for treating foods and/or containing, where once again the same reference signs and part names are used for the same parts as have been used in the preceding FIGS. 1 to 4. To avoid unnecessary repetition, please refer to the detailed description in the above FIGS. 1 to 4. In FIG. 5, a UV irradiation apparatus 47 is operatively placed directly after a membrane filtration system 19. This way a filtered stream 46 can be fed into a UV irradiation apparatus 47 immediately after the filtration process and irradiated. A filtered and irradiated stream 49 of the process liquid can again thereafter be fed back into a conduction element 8 holding and/or conducting the process liquid and/or at least one treatment zone 4. In the example embodiment as in FIG. 5, a filtered and irradiated stream 49 is fed into a treatment zone 4.
It is preferable for the number and irradiation power of the UV irradiation apparatus(es) 47 and the number and filtration capacity of the membrane filtration system(s) 19 in the device 1 to be fixed or designed such that the total process liquid quantity drawn out of at least one conduction element 8 holding and/or conducting the process liquid per time unit for forming at least one stream 20 of the process liquid 3 during continuous treatment can be chosen such that the filtration and UV irradiation of the stream 20 or the streams 20 can achieve a removal rate of micro-organisms that is greater than the growth rate of these micro-organisms in the process liquid 3 in the same interval or time unit.
It is preferable to feed an irradiated and/or filtered stream 46, 48, 49 of the process liquid into a treatment zone 4 and/or a conduction element 8 without conveying means 11. For this purpose, it can be useful for the draining elements 24 of a UV irradiation apparatus 47 and/or of a membrane filtration system 19 to be connected e.g. to a treatment zone 4 in such a way that at least one filtered and/or irradiated stream 46, 48, 49 of the process liquid can be fed into the treatment zone 4 under the influence of gravity, in free fall. Such an example embodiment is shown in FIG. 6 as an example of feeding a filtered and irradiated stream 49 into a treatment zone 4. To avoid unnecessary repetitions, FIG. 6 once again uses the same reference signs and part names for the same parts as are used in the preceding FIGS. 1 and 5.
FIG. 6 depicts an example embodiment of a technical connection of a UV irradiation apparatus 47 to a treatment zone 4 in which a draining element 24 leading from the UV irradiation apparatus 47 to the treatment zone 4 is arranged in such a way that a constant gradient from top to bottom in the direction from the UV irradiation apparatus 47 to the treatment zone 4 is formed, as a result of which the stream 49 of the process liquid 3 conducted away from the UV irradiation apparatus 47 to the treatment zone 4, irradiated, and filtered can flow under the influence of gravity. To introduce the irradiated and filtered stream 49 of the process liquid 3 into the treatment zone 4, one or more opening(s) 25 in the treatment zone 4 can or could easily be designed in the treatment zone 4 or connected to the draining elements 24 so that the irradiated and filtered stream 49 can flow into the treatment zone 4.
Alternately to the design depicted in FIG. 6, only a membrane filtration system or only a UV irradiation apparatus can be placed at this location in the device 1 instead of the combination of one membrane filtration system 19 and one UV irradiation apparatus 47 technically placed one after the other. It is also possible for one only directly filtered stream or one only directly irradiated stream to be fed into at least one treatment zone 4. To achieve this, draining elements of a membrane filtration system or draining elements of a UV irradiation apparatus would be operatively connected to at least one treatment zone.
FIG. 7 depicts excerpts of another, potentially independent embodiment of the device 1, where once again the same reference signs and part names are used for the same parts as have been used in the preceding FIGS. 1 to 6. To avoid unnecessary repetition, please refer to the detailed description in the above FIGS. 1 to 6. FIG. 7 represents an arrangement for feeding an irradiated and filtered stream 49 of the process liquid 3 into a conduction element 8 for the process liquid 3, for example a liquid tank 15. The draining elements 24 again extend from top to bottom in a constant gradient from the UV irradiation apparatus 47 down to the liquid tank 8, 15 so that the irradiated and filtered stream 49 can flow through the opening(s) 25 in the liquid tank 8, 15.
Alternately to the design depicted in FIG. 7, only a membrane filtration system or only a UV irradiation apparatus can again be placed at this location in the device 1 instead of the combination of one membrane filtration system 19 and one UV irradiation apparatus 47 technically placed one after the other. It is therefore again possible for one only directly filtered stream or one only directly irradiated stream to be fed into at least one conduction element 8. To achieve this, draining elements of a membrane filtration system or draining elements of a UV irradiation apparatus would be operatively connected to a conduction element.
FIG. 8 depicts excerpts of another, potentially independent embodiment of the device 1, where once again the same reference signs and part names are used for the same parts as have been used in the preceding FIGS. 1 to 7. To avoid unnecessary repetition, please refer to the detailed description in the above FIGS. 1 to 7. In FIG. 8, a treatment zone 4 is arranged for rinsing the outside 6 of the closed containers 2 filled with food, which at least one treatment zone 4 is arranged at the end of the treatment zone line in the transport direction 26 of the containers 2 through the treatment zones 4. In the example embodiment in FIG. 8, an irradiated and filtered stream 49 of the process liquid 3 is fed into this treatment zone 4 for cleaning the containers 2. The treatment zone 4 is again operatively connected to a draining element 24 of a UV irradiation apparatus 47 for this purpose. In addition, the treatment zone 4 can be assigned e.g. a fan 27 for drying the containers 2 with drying air or another drying device.
Also alternately to the design depicted in FIG. 8, only a membrane filtration system or only a UV irradiation apparatus can again be placed at this location in the device 1 instead of the combination of one membrane filtration system 19 and one UV irradiation apparatus 47 technically placed one after the other. This makes it possible for an only directly filtered stream or an only directly irradiated stream to be fed into the treatment zone 4 for rinsing the containers 2. To achieve this, draining elements of a membrane filtration system or draining elements of a UV irradiation apparatus would be operatively connected to at least one treatment zone and/or a conduction element.
FIG. 9 depicts an example embodiment of a design of a membrane filtration system 19. To avoid unnecessary repetitions, please refer again to the detailed description in the preceding FIGS. 1 to 8, where the same reference signs and part names are used for the same parts as in the preceding FIGS. 1 to 8. Let it be noted at this point that the example embodiment of a membrane filtration system shown in FIG. 9 is only an example and in principle embodiments of a membrane filtration system executed in other ways can be suitable for the method and device for treating foods and containers.
As already explained in detail, during filtration the membrane filtration system 19 as per the example embodiment in FIG. 9 is fed a stream 20 of the process liquid 3 through the feeding elements 22, where a partial quantity fed in per time unit can be specified e.g. using a flow regulator apparatus 18. The stream 20 of the process liquid 3 to be filtered can, for example, be directed by a three-way valve 29 into a pressure vessel 30 in which filter membrane modules 31 are arranged to filter the process liquid 3.
The filter membrane modules 31 shown in FIG. 9 can consist of a great variety of membranes. The construction of the membranes can be homogeneous or inhomogeneous and can exhibit different symmetries in cross-section. In particular, porous membranes in capillary or hollow fibre form and/or flat membranes can be used. The membranes can be made out of various materials. Examples of suitable membrane materials are polyethylene, polypropylene, polyether sulfone, polyvinylidene fluoride, ethylene propylene diene monomer (EDPM), polyurethane, or cellulose acetate. It is preferable to use membrane materials that are hydrophilic. Alternately and/or additionally to plastic membranes, ceramic materials can also be used to form the membranes of the filter membrane modules 31. Particularly suitable are chlorine-resistant membrane materials that can withstand a chlorine exposure of more than 200,000 ppm*h and preferably more than 2,000,000 ppm*h.
The example embodiment shown in FIG. 9 shows operation of the device 1 and the membrane filtration system(s) 19 under high pressure. Alternately or additionally, low pressure zones can also be arranged in at least sections of the device 1; running a membrane filtration system 19 at low pressure is particularly conceivable. For example, suction devices (not shown) can be placed in the draining elements 24, by which a filtered stream 46 of the process liquid 3 can be suctioned from a filter membrane module 31. For this reason, the filter membranes of the filter membrane modules 31 are preferably designed to withstand high and low pressure and suited for trans-membrane pressures and pressure differences of at least 1,000 mbar without permanent blocking of the membranes during ongoing operation of the membrane filtration system 19. Where needed, membranes suitable for pressures of e.g. 2,000 mbar and up to 5,000 mbar over the particular membrane can also be used. During filtration, the transmembrane pressure difference should preferably be less than 5 bar, especially less than 2 bar, and particularly preferably 1 bar or less. It is preferable to use porous membranes, with the effective pore diameter of a particular membrane lying in a range between 0.01 □m and 1 □m, membranes with effective pore diameters between 0.05 □m and 0.5 □m are particularly suitable for the filter membrane modules 31 of the membrane filtration system(s) 19.
The example embodiment shown in FIG. 9 depicts what is called the “outside-in” mode of the membrane filtration system 19, in which the stream 20 of the process liquid 3 to be filtered enters the filter membrane modules 31 from outside during filtration, filters through the filter membranes of the filter membrane modules 31, and a filtered stream 46 of the process liquid 3 is drained out of the inside of the filter membrane modules 31 using draining elements 24. Alternately to the example embodiment shown in FIG. 9, there is also what is called “inside-out” operation in which a stream 20 of the process liquid 3 to be filtered is fed into the inside of the filter membrane modules 31 during filtration and a filtered stream 46 of the process liquid 3 exits on the outside of the filter membrane modules 31. In addition, both a so-called “cross-flow” mode and a cyclical “dead-end” interconnection are possible when it comes to the flow of the stream 20 of the process liquid 3 into a filter membrane module 31. Finally, submerged membrane configurations in which a filtered stream 46 of the process liquid 3 is suctioned off by low pressure are also possible. When a membrane filtration system 19 is in a submerged configuration, a cyclical or acyclical air bubble rinse or air turbulence can be provided or executed to counter the formation of a layer on the membrane surfaces.
In the example embodiment shown in FIG. 9, after the process liquid 3 passes through the filter membrane modules 31 and filtration is completed, the filtered stream 46 of the process liquid 3 is drained out of the membrane filtration system 19 through the draining elements 24 again. As shown in FIG. 9, it can be advisable here to place a receiving container with an overflow 32 in the drain 24, which depending on its dimensions is designed for temporary storage of a certain volume of the filtered process liquid 3 or a filtrate 33. In particular, this filtrate 33 of the process liquid 3 can be used to clean via flushing by reversing the flow direction through the filter membrane modules 31.
To run a cleaning mode for the filter membrane modules 31, closures 34 are placed in the feeding elements 22 and the draining elements 24 that permit mechanical separation of the membrane filtration system 19 from the other structural elements of the device for treating foods and containers. In addition, at least one conveying means 11 is placed in the receiving container 32 and/or a backflush line 35 extending between the receiving container 32 and the draining elements 24 of the membrane filtration system 19. This way appropriate switching of the three-way valves 29 can reverse the flow direction in the membrane filtration system 19 such that the process liquid 3 flows through the filter membrane modules 31 in the reverse direction 36 than in filtration mode. To drain the liquid waste accrued in the course of cleaning by reversing the flow direction through the filter membranes of the membrane filter system 19, the member filter system 19 is assigned at least one closable liquid waste line 37. A quantity of fresh process liquid 3 equal to the drained quantity of liquid waste can, for example, be provided by the feeding device 17 for fresh process liquid 3 shown in FIG. 2.
As further shown in FIG. 9, a dispensing device 38 can be placed in a draining element 24 and/or in the backflush piping 35 of the one membrane filtration system 19 through which the process liquid 3 or the filtrate 33 of the process liquid 3 can be admixed with chemicals from one or more chemical sources 39 both during filtration and when cleaning the membrane filtration system 19. Chemicals can be admixed during filtration through the three-way valve 29 arranged in the drain 24. In addition, an adsorption device 40 can be placed in the drain 24 of the membrane filtration system 19 that allows removal or separation of substances dissolved, suspended, or dispersed in a filtered stream 46 of the process liquid 3.
In connection with the cleaning of the filter membranes of a membrane filtration system 19 by backfiushing it can also be advisable to arrange a UV irradiation apparatus 47 between a membrane filtration system 19 and a receiving container 32, as is shown by way of example in FIG. 9. This permits UV irradiation of the process liquid 3 collected in the receiving container 32 during a backflushing/cleaning process for a membrane filtration system 19 and allows a backfiushing liquid with particularly low germ content to be used for backflushing the filter membranes.
FIG. 10 depicts excerpts of another, potentially independent embodiment of the device 1, where once again the same reference signs and part names are used for the same parts as have been used in the preceding FIGS. 1 to 9. To avoid unnecessary repetition, please refer to the detailed description in the above FIGS. 1 to 9. FIG. 10 depicts sensors 41 that are designed for continuous monitoring of the degree of contamination, especially by measuring the turbidity of the process liquid. Sensors 41 for measuring or monitoring the turbidity of the process liquid can, for example, be placed in the conduction elements 8 and/or in the treatment zones 4 of the device 1.
The measured values of the sensors 41 can be used to assign a UV irradiation apparatus 47 and/or a membrane filtration system 19 to different treatment zones 4 or conduction elements 8 for liquid streams of the process liquid via switching means and directing elements, as shown by way of example in FIG. 10. Switching between conduction elements 8 and/or treatment zones 4 can naturally also be done based on measurements using random samples taken from the device 1.
To switch a membrane filtration system 19 or UV irradiation apparatus 47 to different conduction elements 8, the feeding elements 22 of a UV irradiation apparatus 47 and/or a membrane filtration system 19 can, for example, each be assigned two switching means 42, 42, as shown in FIG. 10. The two depicted switching means 42, 42 are operatively connected to two different conduction elements 8, 8 holding the process liquid in such a way that a stream 20 of the process liquid can be formed either out of one of the two liquid streams 5, 5 of the process liquid in the conduction elements 8, 8 or out of both liquid streams 5, 5. For this purpose the two switching means 42, 42 can be designed as so-called “open-shut valves” so that each of the two switching means 42, 42 can operatively open or close the supply of process liquid into a UV irradiation apparatus 47 and/or a membrane filtration system 19. In the example embodiment shown in FIG. 10, the membrane filtration system 19 shown on the left side also has a UV irradiation apparatus 47 operatively placed directly after it.
A suitable alternative to the example embodiment shown in FIG. 10 would naturally also be one switching means 42 designed as a 3-way switching means (not shown in FIG. 10) for switching the feeding elements 22 of the right-hand UV irradiation apparatus 47 and/or the left-hand membrane filtration system 19 to one of the two conduction elements 8. The switching means 42 designed as 3-way switching means 42 would again be assigned the feeding elements 22 of the UV irradiation apparatus 47 or of the membrane filtration system 19 on the one hand and connected to two different conduction elements 8, 8 on the other hand.
In FIG. 10 and below, the depiction and description using 2-way switching means is maintained for better understanding, with it being noted at this juncture that the placement of a switchable UV irradiation apparatus 47 and/or membrane filtration system 19 on the inlet or outlet side can be designed in numerous ways and is not limited to the example embodiments depicted in FIG. 10 and below.
Instead of switching means 42, a feeding element 22 of a UV irradiation apparatus 47 and/or a membrane filtration system 19 can also be assigned two mixing means 43, 43 as indicated in FIG. 10. The mixing means 43, 43 are again operatively connected to two different conduction elements 8, 8 holding the process liquid in such a way that the stream 20 of the process liquid can again be formed either out of one of the two liquid streams 5, 5 of the process liquid or out of both liquid streams 5, 5 in the conduction elements 8, 8 or by removing and mixing specifiable partial quantities from the two liquid streams 5, 5 of the process liquid. For this purpose, the mixing means 43, 43 can for example be designed as flow regulator valves.
Of course, a UV irradiation apparatus 47 and/or a membrane filtration system 19 can also be assigned more than two switching means 42 and/or mixing means 43, which can accordingly be connected to more than two conduction elements 8. The measured values of the turbidity measurement sensors 41 can, for example, be used to feed a process liquid with relatively low turbidity directly into a UV irradiation apparatus 47. On the other hand, a relatively strongly contaminated or turbid process liquid can be fed into a membrane filtration system 19 based on the turbidity monitoring.
FIG. 11 depicts excerpts of another, potentially independent embodiment of the device 1, where once again the same reference signs and part names are used for the same parts as have been used in the preceding FIGS. 1 to 10. To avoid unnecessary repetition, please refer to the detailed description in the above FIGS. 1 to 10. In the example embodiment depicted in FIG. 11, a drain 24 of a membrane filtration system 19 is assigned three switching means 44, 44. A switching means is operatively connected to a conduction element 8 in the form of a liquid tank 15. Another switching means 44 is operatively connected to a treatment zone 4. A third switching means 44 is connected to a UV irradiation apparatus 47. These example designs of the device 1 can feed a filtered stream 46 of the process liquid 3 either into the conduction element 8 in the form of a liquid tank 15 or the treatment zone 4 or the UV irradiation apparatus 47 or into all of the conduction element 8, the treatment zone 4, and the UV irradiation apparatus 47.
For this purpose, the three switching means 44, 44, 44 in FIG. 11 can again be designed as so-called “open/shut valves” so that each of the three switching means 44, 44, 44 can operatively open or close the discharge of a filtered stream 46 out of the membrane filtration system 19 into the treatment zone 4 and/or the at least one conduction element 8 and/or the at least one UV irradiation apparatus 47.
Instead of switching means 44, a draining element 24 of a membrane filtration system 19 can also be assigned three splitting means 45, 45, 45 as indicated in FIG. 11. A splitting means 45 is again operatively connected to a conduction element 8 in the form of a liquid tank 15. A second splitting means 45 is operatively connected to a treatment zone 4. Finally, a third splitting means 45 is connected to the depicted UV irradiation apparatus 47. Because of this design, the filtered stream 46 of the process liquid 3 can again be fed either into the conduction element 8 designed as a liquid tank 15 and/or the treatment zone 4 and/or the UV irradiation apparatus 47. Alternately, the liquid tank 15 and/or the treatment zone 4 and/or the UV irradiation apparatus 47 can each be fed specifiable partial quantities of the filtered stream 46 of the process liquid 3. For this purpose, the splitting means 45, 45, 45 can, for example, again be designed as flow regulator valves. A membrane filtration system 19 can again be assigned more than three switching means 44 and/or splitting means 45, which can accordingly be connected to multiple conduction elements 8 and/or multiple treatment zones 4 and/or multiple UV irradiation apparatuses 47.
The UV irradiation apparatus 47 depicted in FIG. 11 is connected on the outlet side to at least one treatment zone 4 and/or at least one conduction element 8, 15 by switching means 44 and/or splitting means 45 in order to be able to feed a filtered and irradiated stream 49 into the treatment zone 4 and/or the conduction element 8.
The example embodiments show possible variations of the method and the device for treating foods and/or containers; let it be noted at this juncture that the invention is not limited to the specially portrayed variations of embodiments themselves, but that diverse combinations of the individual variations of embodiments are possible and that this possibility of variation falls within the competence of a person active in this technical field based on the teaching regarding technical action provided by this invention.
Furthermore, individual characteristics or combinations of characteristics from the depicted and described various example embodiments can constitute independent inventive or invented solutions.
The aim underlying the independent invented solutions can be taken from the description.
All information regarding ranges of values in this description should be understood to mean that these include any and all partial ranges, e.g. the statement 1 to 10 should be understood to mean that all partial ranges starting from the lower threshold 1 and the upper threshold 10 are included, i.e. all partial ranges begin with a lower threshold of 1 or larger and with an upper threshold of 10 or less, e.g. 1 to 1.7 or 3.2 to 8.1 or 5.5 to 10.
Above all, the individual embodiments shown in FIGS. 1 to 11 can form the subject of independent invented solutions. The relevant aims according to the invention and solutions can be found in the detailed descriptions of these figures.
As a matter of form, let it be noted that, to facilitate a better understanding of the design of the device for treating foods and/or containers, these and their components have in places been portrayed not to scale and/or enlarged and/or scaled-down.


List of reference signs

1	Device
2	Container
3	Process liquid
4	Treatment zone
5	Liquid stream
6	Outside
7	Spray nozzle
8	Conduction element
9	Collecting tub
10	Means of transport
11	Conveying means
12	Heating means
13	Cooling means
14	Liquid tank
15	Liquid tank
16	Emptying device
17	Feeding device
18	Flow regulator apparatus
19	Membrane filtration system
20	Stream
21	Splitting means
22	Feeding element
23	Three-way splitting valve
24	Draining element
25	Opening
26	Direction of transport
27	Fan
28	Inside
29	Three-way valve
30	Pressure vessel
31	Filter membrane module
32	Receiving container
33	Filtrate
34	Closure
35	Backflush piping
36	Direction
37	Liquid waste line
38	Dispensing device
39	Chemical source
40	Adsorption device
41	Sensor
42	Switching means
43	Mixing means
44	Switching means
45	Splitting means
46	Stream
47	UV irradiation apparatus
48	Stream
49	Stream
50	Flow container

Claims

1-26. (canceled)

27: Method for treating food in at least one treatment zone (4), wherein the food to be treated is filled into containers (2) before the treatment, the containers (2) are closed, and the containers (2) are introduced into a treatment zone (4) and/or transported through a treatment zone (4), and

wherein the treatment zone (4) or the treatment zones (4) are each fed at least one liquid stream (5) of a process liquid (3) to act on the containers (2), wherein the particular liquid stream (5) of the process liquid (3) is tempered before being fed into a treatment zone (4) and the treatment of the food is executed in a treatment zone (4) by heat transfer via a tempered process liquid (3), in which the process liquid (3) flows around an outside (6) of the containers (2), and wherein the process liquid (3) is drained again after completed treatment of the foods out of the treatment zone(s) (4), and

wherein the process liquid (3) is at least partially recirculated into the treatment zone (4) or the treatment zones (4) for re-use in the method,

wherein

out of the total process liquid (3) conducted through all existing treatment zones (4) per unit of time, at least a partial quantity of the process liquid (3) is used per unit of time to form at least one stream (20) of the process liquid (3), and

the at least one formed stream (2) of the process liquid (3) is filtered by at least one membrane filtration system (19) and/or irradiated by at least one UV irradiation apparatus (47),

an irradiated stream and/or filtered stream (46, 48, 49) of the process liquid (3) is fed back into at least one conduction element (8) containing and/or conducting the process liquid (3) and/or into at least one treatment zone (4),

wherein a specifiable quantity of the process liquid (3) is removed out of at least one element (8) containing or conducting the process liquid (3) per time unit in a controlled manner by means of at least one adjustable splitting means (21) or multiple splitting means (21) working together and is used for formation of the at least one stream (20) of the process liquid (3).

28: Method according to claim 27, wherein the temperatures of the particular liquid streams (5) of the process liquid (3) are set separately for each treatment zone (4) in a controlled way before feeding into a treatment zone (4) and the foods being pasteurized in at least one treatment zone (4).

29: Method according to claim 28, wherein the foods being treated are heated successively in at least one treatment zone (4), are pasteurized in at least one treatment zone (4), and are cooled in at least one treatment zone (4).

30: Method according to claim 29, wherein a liquid stream (5) of the process liquid (3) is fed into at least one treatment zone (4) for heating the foods and/or containers (2) at a temperature between 40° C. and 50° C.

31: Method according to claim 27, wherein at least one stream (46) of the process liquid (3) filtered by a membrane filtration system is fed into a UV irradiation apparatus (47) and irradiated immediately after the filtration process and a filtered and irradiated stream (49) of the process liquid (3) is fed back into at least one conduction element (8) holding and/or conducting the process liquid and/or at least one treatment zone (4).

32: Method according to claim 29, wherein process liquid (3) with a temperature between 40° C. and 50° C. is used to form at least one stream (2) of the process liquid to be filtered.

33: Method according to claim 32, wherein the at least one stream (20) is formed by removing process liquid (3) from a tempering-capable flow container (50) for the process liquid (3).

34: Method according to claim 27, wherein the process liquid quantity used to form at least one stream (20) of the process liquid (3) out of at least one conduction element (8) holding and/or conducting the process liquid during continuous treatment per unit of time is chosen in such a way that the irradiation and/or filtration of the stream (20) or streams (20) allow a removal rate for micro-organisms to be achieved that is larger than the growth rate of the micro-organisms in the process liquid (3) in the same unit of time.

35: Method according to claim 27, wherein an irradiated and/or filtered stream (46, 48, 49) of the process liquid (3) is fed back into at least one conduction element (8) holding and/or conducting the process liquid and/or into at least one treatment zone (4) under at least approximately ambient pressure in free fall.

36: Method according to claim 27, wherein an irradiated and/or filtered stream (46, 48, 49) of the process liquid (3) is at least partially fed into a treatment zone (4) for rinsing the outside (6) of closed containers filled with food (2) placed at the end of the process in the method for treating foods and or containers (2) for holding the foods.

37: Method according to claim 27, wherein the degree of contamination of the process liquid (3) is continuously monitored, especially by measurements of the turbidity of the process liquid using sensors (41) placed in conduction elements (8) and/or in treatment zones (4).

38: Methods according to claim 32, wherein a stream (20) of the process liquid (3) to be irradiated and/or filtered is formed as needed out of different conduction elements (8) containing or conducting process liquid, is filtered by at least one membrane filtration system (19), and after the membrane filtration process a filtered stream (46) is fed into at least one conduction element (8) containing or conducting process liquid and/or at least one treatment zone (4) and/or at least one UV irradiation apparatus (47).

39: Device (1) for treating foods in closed containers (2) with a process liquid (3), comprising at least one treatment zone (4), which treatment zone (4) is designed to apply the process liquid (3) to the outside (6) of closed containers (2), wherein the process liquid (3) flows around the outside (6) of the closed containers (2),

means of transport (10) for transporting the containers (2) through the treatment zone(s) (4) and conduction elements (8) containing and/or conducting the process liquid for feeding liquid streams (5) of the process liquid (3) into a treatment zone (4) and conduction elements (8) for discharging liquid streams (5) of the process liquid (3) from the treatment zone(s) (4),

additional conduction elements (8) for containing and/or conducting the process liquid (3) in the device (1) and at least one conveying means (11) for conveying liquid streams (5) of the process liquid (3) in the conduction elements (8), wherein the conduction elements (8) are designed and arranged such that the process liquid (3) can be at least partially recirculated again into the treatment zone (4) or into the treatment zones (4), and

wherein the device (1) comprises at least one heating means (12) for heating the process liquid (3) and at least one cooling means (13) for cooling the process liquid (3),

wherein

the device (1) comprises at least one UV irradiation apparatus (47) and at least one membrane filtration system (19), wherein the at least one UV irradiation apparatus (47) and the at least one membrane filtration system (19) are operatively connected to the conduction elements (8) and/or to the treatment zones (4) in such a way that at least some of the total process liquid (3) fed through all existing treatment zones (4) per unit of time can be used to form at least one stream (20) of the process liquid, the formed stream (20) or the formed streams (20) can be filtered by the at least one membrane filtration system (19) and/or irradiated by the at least one UV irradiation apparatus (47), and a filtered and/or irradiated stream (46, 48, 49) of the process liquid can be fed into at least one conduction element (8) and/or at least one treatment zone (4), wherein at least one adjustable splitting means (21) or multiple co-operating splitting means (21) are arranged on an inlet side of the at least one UV irradiation apparatus (47) and/or the at least one membrane filtration system (19) for controlled removal of a specifiable process liquid quantity per unit of time out of at least one conduction element (8) holding or conducting the process liquid (3) and for formation of the at least one stream (20) of the process liquid (3) to be irradiated and/or filtered.

40: Device according to claim 39, wherein is arranged at least one treatment zone (4) for heating the foods and/or containers (2), at least one treatment zone (4) for pasteurizing the foods, and at least one treatment zone (4) for cooling the foods and/or containers in succession along the direction of transport (26) of the foods or containers (2).

41: Device according to claim 39, wherein at least one UV irradiation apparatus (47) is operatively arranged immediately after a membrane filtration system (19) such that a filtered stream (46) of the process liquid can be irradiated by a UV irradiation apparatus (47) immediately after filtration.

42: Device according to claim 39, wherein a feeding element (22) of a membrane filtration system (19) is connected to a tempering-capable flow container (50) for the process liquid (3).

43: Device according to claim 39, wherein the number and irradiation power of the UV irradiation apparatus(es) (47) and the number and filtration capacity of the membrane filtration system(s) (19) are fixed such that the total process liquid drawn out of at least one conduction element (8) containing and/or conducting the process liquid per unit of time for forming at least one stream (20) of the process liquid during continuous treatment can be chosen such that the filtration and irradiation of the stream (20) or the streams (20) can achieve a removal rate of micro-organisms that is greater than the growth rate of the micro-organisms in the process liquid in the same unit of time.

44: Device according to claim 39, wherein in order to recirculate an irradiated and/or filtered stream (46, 48, 49) of the process liquid, draining elements (24) out of at least one UV irradiation apparatus (47) and/or out of at least one membrane filtration system (19) being connected to at least one conduction element (8) and/or at least one treatment zone (4) in such a way that an irradiated and/or filtered stream (46, 48, 49) of the process liquid can be fed into the conduction element(s) (8) and/or the treatment zone(s) (4) under the influence of gravity in free fall.

45: Device according to claim 39, wherein is arranged at least one treatment zone (4) for rinsing the outside (6) of closed containers filled with foodstuffs, which is placed at the end of the treatment zone line in the transport direction (26) of the containers (2) through the treatment zones (4) and which treatment zone (4) is connected to at least one draining element (24) of a UV irradiation apparatus (47) and/or a draining element (24) of a membrane filtration system (19) in order to rinse the containers by feeding in an irradiated and/or filtered stream (46, 48, 49) of the process liquid.

46: Device according to claim 39, wherein sensors (41) are placed in conduction elements (8) and/or in treatment zones (4) to continuously monitor the degree of contamination of the process liquid (3), especially by measuring the turbidity of the process liquid (3).

47: Device according to claim 39, wherein at least one switching means (42) is assigned to a feeding element (22) of a membrane filtration system (19) that is operatively connected to at least two different conduction elements (8) holding the process fluid in such a way that the stream (20) of process liquid to be filtered can be formed as needed either from one of the liquid streams (5) or multiple liquid streams (5) of the process liquid (3) in the conduction elements (8) or from multiple liquid streams (5).

48: Device according to claim 39, wherein at least one mixing element (43) is assigned to a feeding element (22) of a membrane filtration system (19) that is operatively connected to at least two different conduction elements (8) holding the process fluid in such a way that the stream (20) of process liquid to be filtered can be formed as desired either from one of the liquid streams (5) or multiple liquid streams (5) of the process liquid in the conduction elements (8) or a stream (20) of the process liquid to be filtered by the membrane filtration system (19) can be formed by removing and mixing specifiable partial quantities from multiple liquid streams (5) of the process liquid.

49: Use of a membrane filtration system (19) and a UV irradiation apparatus (47) for continuous cleaning and sterilization of a process liquid (3) in a device (1) for pasteurizing foods in containers (2), according to claim 39.