EP4337903A1

EP4337903A1 - Drying device for drying containers containing cleaning fluid, control device, and method

Info

Publication number: EP4337903A1
Application number: EP22724225.2A
Authority: EP
Inventors: Wilko Harms; Ulf Reinhardt
Original assignee: Belvac Production Machinery Inc
Current assignee: Belvac Production Machinery Inc
Priority date: 2021-05-11
Filing date: 2022-04-21
Publication date: 2024-03-20
Also published as: JP2024516905A; CA3218638A1; DE102021112211A1; DE102021112211B4; WO2022237931A1; CN117321367A; BR112023023641A2; KR20240018459A

Abstract

The invention relates to a drying device (1, 100, 150) for drying containers that contain cleaning fluid, particularly beverage cans, comprising a drying chamber (2, 102) for supplying a drying fluid to the containers in order to remove the cleaning fluid, and an oxygen sensor arrangement (28, 128, 172) which is arranged and configured to determine a final oxygen content of the drying fluid exiting the drying chamber (2, 102).

Description

Drying device for drying containers containing cleaning fluid, control device and method

The invention relates to a drying device for drying containers containing cleaning fluid, in particular beverage cans, a control device for controlling the drying of containers containing cleaning fluid, in particular beverage cans, a manufacturing system for producing containers, in particular beverage cans, and a method for drying containers containing cleaning fluid Containers, in particular beverage cans.

Drying devices for drying containers containing cleaning fluid are known in principle. The production process of containers, especially beverage cans, is characterized by several process steps. Cleaning processes are usually required between individual process steps. During the cleaning process, the containers, in particular the beverage cans, are cleaned with a cleaning fluid. So that the subsequent process step can be executed with the predefined parameters 2, the containers, especially the beverage cans, are to be dried after the cleaning process.

To dry the containers, in particular the beverage cans, they are subjected to a drying fluid, which usually has temperatures between 100.degree. C. and 250.degree. The drying fluid is, for example, with a

speed from 2 m/s to 10 m/s. The drying fluid is usually air.

The drying fluid is to be provided in such a way that components of the cleaning fluid, in particular water molecules, can be absorbed. This means, for example, that the drying fluid should only be saturated at the end of a drying section.

The drying of containers, especially beverage cans, is energy-intensive. The drying devices are usually operated at full load so that the containers, in particular the beverage cans, are dried reliably. The amount of cleaning fluid introduced, for example in the form of the loading of the containers with the cleaning fluid and/or in terms of the number of containers per unit of time, is usually not taken into account. Therefore, the efficiency of drying devices can be improved. The existing devices and methods have different advantages, but further improvements are desirable, particularly with regard to efficiency.

It is therefore an object of the invention to provide a drying device for drying containers containing cleaning fluid, in particular beverage cans, a control device for controlling the drying of containers containing cleaning fluid, in particular beverage cans, a manufacturing system for producing containers, in particular beverage cans, and a method for Drying of cleaning fluid having containers, especially beverage cans, to provide that reduce or eliminate one or more of the disadvantages mentioned. Furthermore, it is an object of the invention to provide a solution that enables efficient drying of containers containing cleaning fluid, in particular - 3 - of beverage cans. At least one object of the invention is to provide an alternative solution for drying containers containing cleaning fluid, in particular beverage cans.

This object is achieved with a drying device, a control device and a method having the features of the independent patent claims. Further advantageous refinements of these aspects are specified in the respective dependent patent claims. The features listed individually in the patent claims and the description can be combined with one another in any way that makes sense from a technological point of view, with further variants of the invention being shown.

According to a first aspect, the invention relates to a drying device for drying containers containing cleaning fluid, in particular beverage cans, comprising a drying chamber for subjecting the container to a drying fluid to remove the cleaning fluid, and an oxygen sensor arrangement which is arranged and configured to measure a final oxygen content of the To determine drying chamber escaping drying fluid.

The invention is based on the knowledge that efficient drying of the containers is not possible with a drying device running under full load. An amount of drying fluid to be fed into the drying chamber can be regulated, for example, by a sensor determining the amount of cleaning liquid vapor in the drying fluid. At the end of the drying chamber, the drying fluid should be saturated or slightly undersaturated with the vapor to allow for the highest possible efficiency, which is why the water vapor content was measured directly. However, this approach has not led to a satisfactory result in practice.

The invention was therefore also based on the finding that water vapor at temperatures above 100° C. cannot be determined directly, or only with great effort, because the gas molecules behave like an ideal gas. Below 100 °C the water is dissolved in the air. At over 100 °C, however, the molecules of the air-water mixture have equal rights, so that one molecule that enters displaces another. Because of this process of displacement - 4 - conventional methods for determining the degree of saturation are not suitable or only suitable to a limited extent.

The inventors have found that the determination of saturation based on the oxygen content within the drying chamber is made possible precisely. The lower the oxygen content in the drying fluid, the higher the cleaning fluid content, in particular the water content. In the event that no oxygen is present, it can be assumed that only water is present. Basically, it can be assumed that the drying fluid has the atmospheric oxygen content of 21% when it enters the drying chamber. If the proportion of oxygen now at the output of the

drying chamber is 0%, it can be assumed that the water content is 100%, i.e. the drying fluid is saturated.

The drying device has the drying chamber for applying the drying fluid to the containers. For this purpose, the drying chamber preferably has a fluid supply for supplying the drying fluid into the drying chamber. In addition, it is preferred that the drying chamber has a fluid discharge for disposal or return of the drying fluid from the drying chamber.

The drying fluid preferably includes fresh fluid from the environment of the drying device and/or tapping fluid that was removed from the drying chamber. The drying device preferably has one of the fresh fluids, ie the fluid that enters the drying device. Furthermore, the drying chamber preferably has a fluid flow of a used fluid which exits from the drying chamber and the drying device. In addition, the drying device can have a fluid flow of tapping fluid, which is removed from the drying chamber and fed back to the drying chamber, with this preferably being heated up and/or mixed with fresh fluid before it is fed in. The fluid flow described below is the fluid flow of the drying fluid, the fresh fluid, the zapping fluid and/or the used fluid.

The drying device can be set up to between 5,000 cubic meters per hour and 50,000 cubic meters per hour of drying fluid in the - 5 -

On and / or discharging drying chamber. The drying fluid preferably has a temperature between 100°C and 250°C, in particular between 150°C and 210°C, for example 180°C. The drying fluid is preferably heated with a heating device described below, which is designed, for example, as a gas burner or is electrically heated.

The drying device preferably has a transport unit for moving the containers with a direction of movement through the drying chamber. The transport unit is preferably set up to convey 2,000 to 4,000 containers, in particular beverage cans, per minute. The drying chamber preferably extends from a chamber entrance through which the containers enter the drying chamber to a chamber exit through which the containers exit the drying chamber.

The drying fluid entering the drying chamber is preferably a mixture of make-up fluid and tap fluid removed from the drying chamber. The fresh fluid is, for example, air that is taken from the area around the drying device. The bleed air is, for example, a quantity of drying fluid which is removed from the drying chamber at the end of a drying section and which is already loaded with the cleaning fluid. It is preferred that the drying device has a fluid return for providing the tap fluid removed from the drying chamber. Furthermore, it is preferred that the drying device has a mixing chamber for mixing the fresh fluid and the tapping fluid.

Air baffle plates for distributing the drying fluid in the drying chamber are preferably arranged in the drying chamber adjacent to the fluid supply. The air baffles can, for example, within the

Be arranged drying chamber. In addition, it is preferred that a fluid distribution device with two or more, in particular a large number of, openings is arranged adjacent to the fluid supply. In a preferred embodiment variant of the drying device, it is provided that it has a fluid collection device for disposing of the drying fluid contaminated with the cleaning fluid through the fluid discharge. The fluid collection device 6 is in particular fluidly coupled to the fluid discharge. For example, the fluid collection device may be or include a tubular member having a plurality of openings.

Furthermore, it is preferred that the drying device has a fluid flow device, in particular a fan, which is arranged in a fluid flow direction of the drying fluid in front of the fluid supply. In addition, it is preferred that a fluid baffle plate is arranged in front of the fluid flow device in the fluid flow direction, in order to guide a fluid in a targeted manner to the fluid flow device. The oxygen sensor assembly is arranged and configured to

to determine the final oxygen content. The final oxygen content is in particular the oxygen content of the drying fluid exiting the drying chamber. The oxygen sensor arrangement can, for example, measure the final oxygen content at the fluid discharge. Alternatively, the oxygen sensor arrangement can also measure the final oxygen content within the drying chamber, with this measurement preferably being carried out adjacent to the fluid discharge.

A preferred embodiment variant of the drying device is characterized in that it comprises a control device which is coupled in terms of signals to the oxygen sensor arrangement and is set up to control a fluid flow, in particular a fluid flow of the drying fluid, the fresh fluid, the

Waste fluid and/or the tap fluid and/or a temperature of the drying fluid entering the drying chamber as a function of at least one output signal of the oxygen sensor arrangement.

The fluid flow controlled by the control device is in particular the volume entering the drying chamber per unit of time and/or the amount of drying fluid entering per unit of time. The fluid flow of the fresh fluid is in particular the volume of fresh fluid entering the drying device per unit time, in particular fresh air from outside the drying device, and/or the quantity of fresh fluid entering the drying device per unit time. - 7 -

For this purpose, the control device is preferably coupled to fluid inlet regulators and/or fluid outlet regulators, which will be explained in more detail below. Furthermore, the control device is preferably coupled to a heating device in order to control the temperature of the drying fluid entering the drying chamber. The output signal of the oxygen sensor arrangement preferably characterizes an oxygen content, in particular a final oxygen content, of the drying fluid.

The control of the fluid flow and/or the temperature and thus indirectly the saturation of the drying fluid enables the containers to be dried efficiently. In particular, an oxygen content can thus be set which represents the highest possible saturation of the drying fluid with the cleaning fluid. In this way, the drying process can be run close to an optimum which, on the one hand, enables reliable drying of the containers and, at the same time, reduces the consumption of resources for generating the fluid flow and/or for heating the air.

In a further preferred embodiment of the drying device it is provided that the control device is set up, a

Fluid moisture, in particular a humidity of the

Drying chamber exiting drying fluid to determine based on the final oxygen content.

By means of such a determination, the controller can adjust the fluid flow and/or the temperature of the drying fluid such that the fluid humidity is 100% saturation or slightly below, for example between 90% and 100%, 95% and 100%, 97.5% and 100%. , amounts to. A further preferred development of the drying device is characterized in that the control device is set up to increase the fluid flow and/or the temperature of the drying fluid entering the drying chamber when a threshold value of the fluid moisture is exceeded. The fluid humidity threshold is preferably predefined. For example, the fluid humidity threshold may be between 90% and 100%, between 95% and 100%, between 97.5% and 100%. For example, if the threshold is 100%, exceeding the threshold would 8 mean that the drying fluid exiting the drying chamber is saturated and could not absorb any further cleaning fluid. There is therefore a risk that the containers have not been completely dried.

In addition, it is preferred that the control device is set up to reduce the fluid flow and/or the temperature of the drying fluid entering the drying chamber when the fluid humidity falls below the threshold value. For example, if the threshold is set at 95% and the drying fluid has a fluid humidity of 90%, this means that the drying fluid is not saturated and the fluid flow is either set too high and/or the temperature is too high. A fluid flow that is too high and/or a temperature that is too high result in unnecessary energy consumption, which increases the resource requirements of the drying device and thus of the entire manufacturing process of the containers.

It is further preferred that the control device is set up to regulate the fluid flow and/or the temperature by means of the threshold value, in particular by means of an upper and/or a lower threshold value.

It is particularly preferred that the control device is set up so that the fluid humidity does not exceed and/or fall below a threshold value. In particular, it is preferred that the control device is set up such that an upper threshold value of the fluid humidity is not exceeded and/or a lower threshold value of the fluid humidity is not undershot. Regarding possible

Humidity values for the upper and/or lower threshold are referenced to the appropriate values below. In a further preferred embodiment variant of the drying device, it is provided that it comprises a heating device coupled to the control device in terms of signals for setting, in particular for increasing and/or reducing, the temperature of the drying fluid entering the drying chamber. The heating device is preferably designed to heat electrically and/or emit exhaust gases, for example as a gas burner. - 9 -

A heating device coupled to the control device in terms of signals enables the drying fluid to be heated in a targeted manner in such a way that the fluid humidity and/or the final oxygen content can be set in an efficiency-maximizing manner. A further preferred development of the drying device is characterized in that the oxygen sensor arrangement is designed to determine an initial oxygen content of the drying fluid entering the drying chamber. The drying fluid entering the drying chamber already has a temperature of usually over 100° C., so that the problem of behavior as an ideal gas mentioned at the beginning occurs.

In the case of an exhaust gas-emitting heating device, for example a gas burner, water is emitted as a reaction product. As a result, the drying fluid already contains a non-negligible amount of water. This water is already taken into account by measuring the initial oxygen content, for example adjacent to the fluid supply. A more precise determination of the fluid humidity can thus be carried out by means of a difference calculation.

According to a further preferred embodiment, it is provided that the oxygen sensor arrangement has a first oxygen sensor for determining the final oxygen content and/or a second oxygen sensor for determining the initial oxygen content. The final oxygen content and/or the initial oxygen content can be determined in a targeted manner by means of individual oxygen sensors. In addition, it is preferred that two or more first oxygen sensors and/or two or more second oxygen sensors are arranged and/or are comprised by the oxygen sensor arrangement.

Another preferred embodiment of the drying device is characterized in that the oxygen sensor arrangement directly or indirectly determines the final oxygen content and/or the initial oxygen content, in particular the first oxygen sensor determines the final oxygen content and/or the second oxygen sensor determines the initial oxygen content. An indirect determination of the final oxygen content and / or the initial oxygen content can be done, for example, by measuring nitrogen, since the 10

Mixing ratios of nitrogen and oxygen and the other components of air are usually known. The first oxygen sensor and/or the second oxygen sensor is/are preferably designed as a nitrogen sensor or nitrogen sensors. A further preferred development of the drying device is characterized in that it comprises a fluid flow unit, which is coupled in terms of signals to the control device, for setting, in particular for increasing and/or reducing, a fluid flow. The fluid flow is in particular a fluid flow of the drying fluid entering the drying chamber. Thus, the efficiency of the

Drying process can be increased by adjusting the fluid flow such that the drying fluid is saturated or nearly saturated at the fluid discharge.

In a further preferred embodiment variant, the drying device comprises a fluid inlet for the inlet of drying fluid, in particular fresh fluid, the fluid inlet having a fluid inlet regulator for regulating the drying fluid, in particular fresh fluid, entering the drying device through the fluid inlet. The fluid inlet regulator can be designed, for example, as an adjustable flap. The fresh fluid is preferably fresh air, for example, in the vicinity of

Drying device is located. The addition of fresh fluid to the drying fluid advantageously enables a reduction in the fluid moisture content of the drying fluid.

In addition, it is preferred that the drying device comprises a fluid outlet for disposing of the drying fluid or used fluid from the drying chamber, the fluid outlet having a fluid outlet regulator for controlling the drying fluid or used fluid exiting the drying chamber through the fluid outlet. The fluid outlet regulator can be designed, for example, as an adjustable flap. It is particularly preferred that the drying device is designed in such a way that part of the drying fluid or the used fluid exits the drying chamber through the fluid outlet and another part of the drying fluid, namely the - 11

Tapping fluid is fed back to the drying fluid entering the drying chamber.

It is preferred that the control device is set up to control the fluid inlet regulator and the fluid outlet regulator in such a way that the volume entering through the fluid inlet essentially corresponds to the volume exiting from the fluid outlet. This ensures that as little air as possible enters through a chamber inlet through which the containers enter the drying chamber and/or exits through a chamber exit through which the containers exit the drying chamber. A further preferred development of the drying device comprises a heat exchanger which is arranged in such a way that a drying fluid, in particular fresh fluid, entering through the fluid inlet is heated by means of a drying fluid, in particular used fluid, exiting the drying chamber. Incoming drying fluid is preheated with the heat exchanger, so that less energy is required to heat the drying fluid before it is introduced into the drying chamber.

According to a further aspect, the object mentioned at the outset is achieved by a control device for controlling the drying of containers containing cleaning fluid, in particular beverage cans, which is set up to regulate a fluid flow and/or a temperature of the drying fluid entering a drying chamber of a drying device as a function of at least one Set the output of an oxygen sensor assembly. The control device is set up in particular for use in a drying device described above. The control device is set up in particular to determine a fluid humidity, in particular an air humidity, of the drying fluid exiting the drying chamber based on the final oxygen content and preferably to increase the fluid flow and/or the temperature of the drying fluid entering the drying chamber if a threshold value of the fluid humidity is exceeded, and /or to reduce the fluid flow and/or the temperature of the drying fluid entering the drying chamber when the humidity falls below the threshold value. - 12

In a further preferred embodiment variant it is provided that the control device is set up to set an operating mode with minimum energy at a final oxygen content of less than or equal to 100%, the operating mode determining the temperature of the drying fluid, in particular at the fluid supply, the fluid flow of the drying fluid into the drying chamber and/or or the fluid flow of the used fluid exiting from the fluid outlet. The minimum energy operating mode is characterized in that the drying device has a minimized energy consumption when this operating mode is set. The temperature of the drying fluid, the fluid flow of the drying fluid into the drying chamber and the exiting fluid flow of the used fluid are the main control variables influencing the drying of the containers and are jointly responsible for the energy consumption of the drying device. By setting an operating mode of minimum energy, the containers can thus be dried with minimum energy consumption.

According to a further aspect, the object mentioned at the outset is achieved by a manufacturing system for manufacturing containers, in particular beverage cans, comprising a drying device according to one of the embodiment variants described above and/or a control device according to one of the embodiment variants described above.

According to a further aspect, the object mentioned at the outset is achieved by a method for drying containers containing cleaning fluid, in particular beverage cans, comprising the steps: subjecting the container to a drying fluid within a drying chamber and determining a final oxygen content of the drying fluid exiting the drying chamber.

It is further preferred that the method comprises the step: determining a fluid humidity, in particular an air humidity, of the drying fluid based on the final oxygen content. It is particularly preferred that this takes place on the basis of a differential calculation. In addition, it is preferred that - 13 - the fluid humidity is additionally based on an initial oxygen content of the drying fluid entering the drying chamber.

The fluid humidity can be determined, for example, as follows: fH20(02)= 100 ^* (1-B/A) where fiH20(02) is the fluid humidity of the drying fluid exiting the drying chamber, i.e. the used fluid, A is the oxygen content of the fresh fluid and/or the initial oxygen content, and B the final oxygen content of the drying fluid determined with the oxygen sensor arrangement. A may or may not be a constant, namely the general oxygen content of the air, ie 21%. When using a gas burner, A is to be treated as a variable depending on the flue gas supplied to the drying fluid.

In a further preferred embodiment variant of the method, it is provided that this comprises the step: setting a fluid flow and/or a temperature of the drying fluid entering the drying chamber in such a way that the fluid humidity of the drying fluid exiting the drying chamber exceeds and/or falls below a threshold value of the fluid humidity . In particular, it is preferred that an upper threshold value of the fluid humidity is not exceeded and/or a lower threshold value of the fluid humidity is not undershot.

The threshold value of the fluid humidity, in particular the upper and/or lower threshold value of the fluid humidity, is preferably less than or equal to 100%. In addition, it is preferred that the upper threshold value is greater than 90%, greater than 95% and/or greater than 97.5%. Furthermore, it is preferred that the lower threshold value is greater than 90%, greater than 95% and/or greater than 97.5%. As long as the fluid humidity is less than or equal to 100%, the drying fluid is in a non-condensing condition. In this way, the containers, in particular the beverage cans, can be safely dried. - 14 -

The method and its possible developments have features or method steps that make them particularly suitable for being used for a drying device and its developments.

For further advantages, design variants and design details of the further aspects and their possible developments, reference is also made to the previously given description of the corresponding features and developments of the drying device.

Preferred exemplary embodiments are explained by way of example with reference to the accompanying figures. FIG. 1 shows a schematic, two-dimensional view of an exemplary embodiment of a drying device;

Figure 2: a schematic, two-dimensional view of a further exemplary embodiment of a

drying device; Figure 3: a schematic, two-dimensional view of a further exemplary embodiment of a

drying device; and

Figure 4: a schematic process.

In the figures, identical or essentially functionally identical or similar elements are denoted by the same reference symbols.

The drying device 1 shown in FIG. 1 has a drying chamber 2 which extends from a chamber inlet 4 to a chamber outlet 6 . The beverage cans 14 are transported into the drying chamber 2 through the chamber inlet 4 by means of a transport unit 12 , pass through the drying chamber 2 in a substantially horizontal direction and exit again at the chamber outlet 6 . The beverage cans 14 entering the drying chamber 2 contain a cleaning fluid, for example water. - 15 -

The purpose of the drying device 1 and the drying chamber 2 is in particular to free the beverage cans 14 from the cleaning fluid. For this purpose, the beverage cans 14 are subjected to a drying fluid. The drying fluid enters the drying chamber 2 through a fluid supply 8 . The drying fluid flows through the drying chamber 2 towards a fluid outlet 10 through which the drying fluid escapes from the drying chamber 2 .

The fluid supply 8 is fluidically coupled to a fluid inlet 20 and a fluid return 18 . As a result, the drying fluid entering the drying chamber 2 through the fluid supply 8 can be a mixture of the fresh fluid entering through the fluid inlet 20 and the tap fluid provided through the fluid return 18 .

A fluid inlet regulator 22 is arranged at the fluid inlet 20 through which a fluid reaches the fluid supply 8 . The fluid inlet regulator 22 is signal-coupled to a control device 34 .

The fluid discharge 10 is fluidically coupled to the fluid return 18 and a fluid outlet 24 . By means of the fluid return 18 is a part of the emerging from the drying chamber 2 drying fluid in the

Drying chamber 2 incoming drying fluid supplied. A part of the escaping from the drying chamber 2 drying fluid can be over the

Fluid outlet 24 escape. The fluid outlet 24 has a fluid outlet regulator 26 which is signal-coupled to the control device 34 .

The drying device 1 also has an oxygen sensor arrangement 28 which is arranged and designed to determine a final oxygen content of the material exiting the drying chamber 2

to determine drying fluids. The oxygen sensor arrangement 28 includes a first oxygen sensor 30 which is arranged on the fluid discharge 10 . With this arrangement, the final oxygen content of the drying fluid exiting the drying chamber 2 can be determined in an advantageous manner. In addition, the oxygen sensor assembly 28 includes a second

Oxygen sensor 32, which is arranged on the fluid supply 8. - 16 -

The drying device 1 also includes a heating device 36, which is embodied in the present case as an electric heating device. The controller 34 is signal-coupled to the heater 36 , the fluid inlet controller 22 and the fluid outlet controller 26 . By determining the final oxygen content with the oxygen sensor arrangement 28, the saturation of the drying fluid at the fluid outlet 10 can be determined. If the fluid humidity exceeds a threshold value, which can be determined with the final oxygen content, the control device 34 is set up to increase the fluid flow and/or the temperature of the drying fluid entering the drying chamber 2, in particular by actuating the heating device 36 and/or the inlet and /or outlet regulator 22, 26.

FIG. 2 shows a further embodiment variant of a drying device 100. In a manner analogous to FIG. The fluid discharge 110 has a fluid discharge air collecting duct 111 . The fluid exhaust air collection channel 111 can have a perforated plate, for example, through which the drying fluid can enter the fluid exhaust air collection channel 111 and can then escape from the fluid outlet 124 of the drying device 100 . The escape of the drying fluid from the fluid outlet 124 is controlled, among other things, by means of a fluid outlet unit 126, which is designed as a fan.

The beverage cans 114 are moved through the drying chamber 102 in the transport direction 116 by means of a transport unit 112 . The drying device 100 also has a fluid return 118 . The drying fluid exiting the drying chamber 102 through the fluid return line 118 is guided into a mixing chamber 119 by means of the latter. The mixing chamber 119 is also fluidically coupled to the fluid inlet 120 .

In the mixing chamber 119 , the drying fluid returned from the drying chamber 2 , which is also referred to as tap fluid, is mixed with fresh fluid through the fluid inlet 120 . By means of the fluid inlet regulator 122 at the fluid inlet 120 and the fluid outlet unit 126 at the fluid outlet 124 - 17 - the mixing ratio of fresh fluid from the environment of the drying device 1 and the returned drying fluid can be adjusted by means of the fluid return 118.

The drying fluid located in the mixing chamber 119 can be heated by means of the heating device 136 . The heating device 136 is designed as a gas burner, which directs a burner flame 138 into the mixing chamber 119 for heating the drying fluid. In particular, the heating device 136 has a separate air supply. The drying fluid in the mixing chamber 119 reaches a fluid flow unit 142 via fluid baffles 140, which is designed, for example, as a fan. The drying fluid is distributed within the drying chamber 2 via further fluid guide plates 144 adjacent to the fluid feed 108 . A further distribution of the drying fluid is achieved by means of the perforated plate 146.

The drying device 100 also has an oxygen sensor arrangement 128 which is arranged and designed to determine a final oxygen content of the drying fluid exiting the drying chamber 2 . For this purpose, it has a first oxygen sensor 130 in the fluid discharge 110 , the first oxygen sensor 130 being arranged adjacent to the fluid outlet 124 . In addition, the oxygen sensor arrangement 128 includes a second oxygen sensor 132 which is arranged between the mixing chamber 119 and the fluid feed 108 .

Furthermore, the drying device 1 includes a control device 134 which is coupled in terms of signals to the oxygen sensor arrangement 128 . The control device 134 is set up to control the fluid flow of the drying fluid entering the drying chamber 2 and/or the temperature of this drying fluid as a function of an output signal from the oxygen sensor arrangement 128 . This takes place in particular on the basis of a calculation within the control device 134, which determines a fluid humidity of the drying fluid exiting the drying chamber 2 on the basis of the final oxygen content.

Figure 3 shows a schematic, two-dimensional view of a further exemplary embodiment of a drying device 150. Die - 18 -

Drying device 150 also has a drying chamber 152 with a chamber inlet 154 and a chamber outlet 156, wherein

Drying fluid is fed into the drying chamber 152 through a fluid inlet 158 and escapes from the drying chamber 152 through a fluid outlet. A fluid flow device 162 is arranged upstream of the fluid feed 158 in the direction of flow.

Drying fluid, in particular fresh fluid, preferably air, flows through a fluid inlet 164 into the drying device 150 . The drying fluid, in particular used fluid, can escape from the drying device 150, in particular from the drying chamber 152, from a fluid outlet 168. Adjacent to the fluid outlet 168 is one

Oxygen sensor assembly 172 arranged.

The drying device 152 comprises a heat exchanger 170 which is arranged in such a way that a drying fluid entering through the fluid inlet 164 is heated by means of the drying fluid exiting the drying chamber 152 . For this purpose, the heat exchanger 170 thermally couples a fluid outlet channel to a fluid inlet channel. The other details of the drying device 150 shown in FIGS. 1 and 2 are not shown in FIG. 3, but can be present in an analogous manner. FIG. 4 shows a schematic method. In step 200, containers 14, 114 are charged with a drying fluid within a drying chamber 2, 102. In step 202, a final oxygen content of the drying fluid exiting the drying chamber 2, 102 is determined. In step 204 a fluid humidity, in particular an air humidity, of the drying fluid is determined based on the final oxygen content.

This can be done, for example, by means of a differential calculation. For example, it is known that the drying fluid entering the drying chamber 2, 102 has an oxygen content of 21%. If the drying fluid exiting the drying chamber has an oxygen content of 0%, this means that this drying fluid is completely saturated, ie has 100% moisture. - 19 -

In step 206, a fluid flow and/or a temperature of the drying fluid entering the drying chamber 2, 102 is adjusted such that the fluid humidity of the drying fluid exiting the drying chamber 2, 102 exceeds a fluid humidity threshold value. In addition, the fluid flow and/or the temperature can be adjusted in such a way that the fluid humidity of the drying fluid exiting the drying chamber is within a threshold range, for example between 95% and 100%. Efficient drying of containers, in particular beverage cans, is made possible by means of the drying device described above and the corresponding method. This is achieved in particular by the fact that the drying fluid has the highest possible saturation, ie high humidity. As a result, the temperature is set as low as possible and the fluid flow is also set as low as possible, so that energy can be saved in this way.

20

REFERENCE MARKS

1 drying device

2 drying chamber

4 Chamber entry 6 Chamber exit

8 fluid supply 10 fluid discharge 12 transport unit 14 beverage cans 16 transport direction 18 fluid return 20 fluid inlet 22 fluid inlet regulator 24 fluid outlet 26 fluid outlet regulator

28 oxygen sensor arrangement 30 first oxygen sensor 32 second oxygen sensor 34 control device 36 heating device

100 drying device 102 drying chamber

104 chamber entry

106 chamber exit - 21

108 fluid supply 110 fluid discharge 111 fluid exhaust air collection channel 112 transport unit 114 beverage cans

116 direction of transport 118 fluid return

119 mixing chamber

120 fluid inlet 122 fluid inlet regulator 124 fluid outlet 126 fluid outlet unit 128 oxygen sensor assembly 130 first oxygen sensor 132 second oxygen sensor

134 controller 136 heater 138 burner flame 140 fluid baffles 142 fluid flow assembly

144 fluid guide plates 146 perforated plate 150 drying device 152 drying chamber 22

154 chamber inlet 156 chamber outlet 158 fluid inlet 160 fluid outlet 162 fluid flow device

164 fluid inlet 166 fluid inlet regulator 168 fluid outlet 170 heat exchanger 172 oxygen sensor assembly

174 heater

Claims

- 23 -

CLAIMS Drying device (1, 100, 150) for drying containers containing cleaning fluid, in particular beverage cans, comprising a drying chamber (2, 102) for applying a drying fluid to the containers to remove the cleaning fluid, and an oxygen sensor arrangement (28, 128, 172 ), which is arranged and configured to determine a final oxygen content of the drying fluid exiting from the drying chamber (2, 102). Drying device (1, 100, 150) according to Claim 1, comprising a control device (34, 134) which is signal-technically coupled to the oxygen sensor arrangement (28, 128, 172) and which is set up to measure a fluid flow and/or a temperature of the fluid fed into the drying chamber (2nd , 102) incoming drying fluid depending on at least one

to control the output signal of the oxygen sensor arrangement (28, 128, 172). Drying device (1, 100, 150) according to any one of the preceding claims, wherein the control device (34, 134) is set up, a fluid humidity, in particular an air humidity, of the

Drying chamber (2, 102) to determine exiting drying fluid based on the final oxygen content. Drying device (1, 100, 150) according to the preceding claim 3, wherein the control device (34, 134) is set up to increase the fluid flow and/or the temperature of the drying fluid entering the drying chamber (2, 102) when a threshold value of the fluid moisture is exceeded increase, and/or if the fluid humidity falls below the threshold value, the fluid flow and/or the temperature of the fluid in the drying chamber (2,

102) to reduce incoming drying fluid. Drying device (1, 100, 150) according to one of the preceding claims, - 24 - comprising a heating device (36, 136) coupled in terms of signals to the control device (34, 134) for adjusting, in particular for increasing and/or reducing, the temperature of the drying fluid entering the drying chamber (2, 102), with preferably the Heating device (36, 136) is designed to heat electrically and/or emit exhaust gas.

6. Drying device (1, 100, 150) according to any one of the preceding claims, wherein the oxygen sensor arrangement (28, 128, 172) for determining a

Initial oxygen content of the drying chamber (2, 102) entering the drying fluid is formed.

7. Drying device (1, 100, 150) according to any one of the preceding claims, wherein the oxygen sensor arrangement (28, 128, 172) has a first

Oxygen sensor (30, 130) for determining the final oxygen content and/or a second oxygen sensor (32, 132) for determining the initial oxygen content. 8. Drying device (1, 100, 150) according to any one of the preceding claims, wherein the oxygen sensor arrangement (28, 128, 172) the

The final oxygen content and/or the initial oxygen content, in particular the first oxygen sensor determines the final oxygen content and/or the second oxygen sensor determines the initial oxygen content, directly or indirectly.

9. Drying device (1, 100, 150) according to one of the preceding claims, comprising a fluid flow unit (142) coupled in terms of signals to the control device (34, 134) for setting, in particular for increasing and/or reducing, a fluid flow.

10. Drying device (1, 100, 150) according to any one of the preceding claims, comprising - 25 - a fluid inlet (20, 120) for inlet of drying fluid, the fluid inlet (20, 120) having a fluid inlet regulator (22, 122) for regulating the flow through the fluid inlet (20, 120) into the

Drying device (1, 100) entering drying fluid, and/or a fluid outlet (24, 124) for disposing of the drying fluid from the drying chamber (2, 102), the fluid outlet (24, 124) having a fluid outlet regulator (26, 126) for regulation of the drying fluid exiting the drying chamber (2, 102) through the fluid outlet (24, 124), the control device (34, 134) preferably being set up to control the fluid inlet controller (22, 122) and the fluid outlet controller (26, 126) in such a way control that the volume entering through the fluid inlet (20, 120) substantially equals the volume exiting the fluid outlet (24, 124).

11. Control device (34, 134) for controlling the drying of containers containing cleaning fluid, in particular beverage cans, which is set up to regulate a fluid flow and/or a temperature of the fluid entering a drying chamber (2, 102) of a drying device (1, 100). Adjust drying fluids depending on at least one output signal of an oxygen sensor arrangement (28, 128, 172). 12. Control device (34, 134) according to the preceding claim 11, which is set up to determine a fluid humidity, in particular an air humidity, of the drying fluid exiting the drying chamber (2, 102) based on the final oxygen content and preferably when a threshold value of the fluid humidity is exceeded the fluid flow and/or the temperature of the liquid in the drying chamber (2,

102) to increase the drying fluid entering and/or to reduce the fluid flow and/or the temperature of the drying fluid entering the drying chamber (2, 102) if the fluid humidity falls below the threshold value. - 26 -

13. Production system for producing containers, in particular beverage cans, comprising a drying device (1, 100) according to any one of the preceding claims 1-10 and/or a control device

(34, 134) according to any one of the preceding claims 11-12.

14. A method for drying cleaning fluid having containers, in particular beverage cans, comprising the steps: - Applying a drying fluid to the container within a

drying chamber (2, 102), and

Determining a final oxygen content of the drying fluid exiting the drying chamber (2, 102). 15. The method of claim 14, comprising the step of:

Determining a fluid humidity, in particular an air humidity, of the drying fluid based on the final oxygen content. 16. The method according to any one of the preceding claims 14-15, comprising the

Step:

Adjusting a fluid flow and/or a temperature of the drying fluid entering the drying chamber (2, 102) such that the fluid humidity of the drying fluid exiting the drying chamber (2, 102) exceeds a fluid humidity threshold.