Method and device for recovering energy in a bottle cleaning machine

Abstract

The container cleaning device (100, 200, 300) according to the invention comprises a cleaning zone (91, 92) for cleaning the containers; a cooling zone (93) for cooling the containers, wherein an air stream (15) laden with water vapor can be generated; and a heat transport device (80) with a working medium (81) for absorbing heat from the water vapor of the air stream and for supplying absorbed heat to the cleaning zone.

Description

Field of the invention

[0001] The invention relates to a container cleaning device and a method for cleaning containers. State of the art

[0002] Special container cleaning systems have been established for cleaning bottles. The cleaning process requires the bottles to first be heated and then cooled again. This process results in the air within the system being saturated with moisture. Since the air condenses upon contact with the cooler outside air, air extractors are located at the system's openings to prevent the moist air from escaping into the environment. However, the heat energy stored in the moist air is lost during extraction. Description of the invention

[0003] The object of the invention is to at least partially mitigate or eliminate the above-mentioned disadvantages.

[0004] The problem is solved by a device according to patent claim 1.

[0005] The container cleaning device according to the invention comprises a cleaning zone for cleaning the containers; a cooling zone for cooling the containers, wherein an air stream laden with water vapor can be generated; and a heat transport device with a working medium for absorbing heat from the water vapor of the air stream and for supplying the absorbed heat to the cleaning zone. The container cleaning device can, in particular, be a bottle cleaning device.

[0006] The device according to the invention has the advantage that energy can be extracted from the water vapor-enriched or saturated air and fed into the cleaning zone. This prevents or reduces energy loss.

[0007] The device according to the invention can be further developed as follows.

[0008] The heat transfer device may comprise a heat pump for increasing the temperature of the working fluid after absorbing heat from the water vapor in the air stream and before supplying the absorbed heat to the cleaning zone. In this way, the efficiency of energy transfer to a fluid in the cleaning zone can be improved.

[0009] The working fluid can absorb heat from the condensation enthalpy of the water vapor. The energy stored in the water vapor (evaporation enthalpy) is comparatively high and can be recovered as condensation enthalpy.

[0010] To absorb the heat from the air flow, at least one first heat exchanger through which the working medium flows can be provided in the cooling zone. Furthermore, at least one second heat exchanger through which the working medium flows can be provided in the cleaning zone to supply heat from the working medium to the cleaning zone. This offers the advantage that a working medium circuit can be provided to absorb the heat at one point and release it again at another point, without requiring direct contact between the working medium and another fluid.

[0011] At least one additional heat exchanger can be provided to absorb thermal energy from the cooling zone and / or wastewater from the cleaning zone into the working medium. This leads to further energy recovery.

[0012] In the container cleaning device, the absorbed heat can be supplied for heating at least one cleaning liquid in the cleaning zone.

[0013] In particular, the absorbed heat can be applied to a cleaning fluid in a pretreatment zone or heating zone for the containers in the cleaning zone. This is advantageous because energy is required for heating at these points.

[0014] The air flow may extend at least partially along a transport direction of the containers in the cooling zone.

[0015] The containers can be cooled along the transport direction from a first, higher temperature to a second, lower temperature, whereby the air flow, which has been cooled by the heat absorbed by the working medium, can be directed against the transport direction of the containers and fed back to containers with the first temperature.

[0016] This can be further developed in such a way that at least one channel can be provided for guiding the cooled air flow against the transport direction of the containers.

[0017] The above-mentioned object is also achieved by the method according to patent claim 10.

[0018] The method according to the invention for cleaning containers, in particular bottles, comprises the steps of: cleaning the containers in a cleaning zone; cooling the containers in a cooling zone, whereby an air stream laden with water vapor is generated; and absorbing heat from the water vapor of the air stream into a working medium and supplying absorbed heat from the working medium into the cleaning zone by means of a heat transport device, whereby the heat is absorbed in particular from condensation enthalpy of the water vapor.

[0019] The advantages of the method according to the invention and its further developments correspond to those of the device according to the invention and its further developments.

[0020] The method according to the invention can be further developed as follows.

[0021] The method may comprise the following further step: increasing the temperature of the working medium after absorbing heat from the water vapor of the air stream and before supplying absorbed heat to the cleaning zone with a heat pump.

[0022] The further step of cooling the containers along a transport direction of the containers from a first, higher to a second, lower temperature may be provided.

[0023] The following further steps can be carried out: directing the air flow, which has been cooled by the heat absorbed by the working medium, against the transport direction of the containers; and supplying the cooled air flow to the containers with the first temperature.

[0024] Further features and exemplary embodiments, as well as advantages of the present invention, are explained in more detail below with reference to the drawings. It is understood that this embodiment cannot exhaust the entire scope of the present invention. It is further understood that some or all of the features described below can also be combined in other ways.

[0025] The principle of the invention can be applied in a similar and simple manner to container processing machines such as tunnel pasteurizers or tunnel coolers. These machines also generate large quantities of water vapor-containing air during operation, the energy content of which can be utilized in process steps within the device itself or elsewhere. Brief description of the drawings

[0026] Fig. 1 shows a first embodiment of the container cleaning device according to the invention. Fig. 2 shows a second embodiment of the container cleaning device according to the invention. Fig. 3 shows a third embodiment of the container cleaning device according to the invention. Description of the embodiments Preliminary remarks

[0027] The cleaning process results in moisture-enriched or saturated air within the container cleaning device. Due to the evaporation enthalpy of water, this air contains a high level of energy. If this energy is extracted and released into the environment via a chimney, the same amount of energy must be fed back into the container cleaning device via a heater to maintain a constant cleaning temperature. At the same time, the warm air flow at the outlet is directed such that it flows from the warmer baths towards the cooler outlet zone (cooling zone). This causes condensation to form in the outlet zone, which acts as a breeding ground for germs and can lead to contamination with condensation when it drips into the cleaned containers (bottles).On the other hand, the containers (bottles) are heated by the warm air flow, although they should be cooled down in order to avoid losing further energy from the system due to a higher container temperature (bottle temperature).

[0028] In one embodiment, the invention provides for the exhaust air flow to be passed through a heat exchanger. Due to the cool surface temperature in the heat exchanger, the water in the air flow condenses, and the energy of the evaporation enthalpy is released. This allows the fluid (working medium) flowing through the heat exchanger to be heated. By coupling the fluid flow of the heat exchanger with a heat pump, energy can be provided at a temperature level that can be used to heat the cleaning machine, e.g., to heat the pretreatment zone.

[0029] In a further embodiment of the invention, it is possible to reverse the air volume flow within the cleaning device, i.e., to allow it to flow against the direction of container movement. In this case, the intake opening of the extraction system is relocated further into the interior of the machine, e.g., to the area where the bottle cooling zone begins. The extracted air is passed through the heat exchanger. The cooled air can then be fed back into the cleaning device at the container (bottle) discharge point, or at the point where the extraction system is located, via a duct system. This prevents the formation of condensate at the container (bottle) outlet and assists in drying and cooling the containers.

[0030] An extension of the design provides for coupling the air heat exchanger (which transfers the evaporation enthalpy energy from the air stream to the working medium) with one or more additional heat exchangers. This offers the advantage that even more energy from the cleaning device can be recovered with just one heat pump. The additional heat exchangers can be fluid heat exchangers (in particular, liquid heat exchangers), allowing additional energy to be recovered from the cooling zone and / or wastewater, for example. Advantages of the invention

[0031] Energy recovery of the evaporation enthalpy from the exhaust air stream Cleaning machines with less energy consumption Better TCO calculation for customers Less condensate formation at the bottle discharge Reduced recontamination of the containers Better drying of the bottles Better cooling of the bottles and thus further energy savings Embodiments of the drawings

[0032] Fig. 1 shows a first embodiment of the container cleaning device 100 according to the invention.

[0033] The container cleaning device 100 comprises a cleaning zone 91, 92 for cleaning containers (not shown), wherein the containers are, for example, bottles. The cleaning zone 91, 92 here comprises a pretreatment zone 91, in which the containers are preheated and / or precleaned and / or residues are soaked thereon, e.g., by spraying them with warm water. The cleaning zone further comprises a main cleaning zone 92, following the pretreatment zone 91 in the process flow, in which the containers are completely cleaned.

[0034] In addition, a cooling zone 93 is provided for cooling the containers. There, the containers are gradually cooled and then discharged from the container cleaning device 100. In the cooling zone 93, an air stream 15 enriched with water vapor is generated by extracting this moist air with a fan 20.

[0035] The container cleaning device 100 further comprises a heat transport device 80 with a working medium 81 for absorbing heat from the water vapor of the air stream 15 and for supplying the absorbed heat to the cleaning zone 91, 92. Energy is extracted from the water vapor-enriched or saturated air and supplied to the cleaning zone (pretreatment zone 91 and / or main cleaning zone 92). This avoids or reduces energy loss. The working medium is a fluid in a pipeline that can absorb heat. A pump 70 is provided for transporting the working medium 81. The working medium 81 is circulated via piping.

[0036] In this embodiment, the heat transport device 80 comprises a heat pump 40 for increasing the temperature of the working medium 81 after absorbing heat from the water vapor of the air stream 15 and before supplying the absorbed heat to the cleaning zone 91, 92. This allows the working medium to enter the cleaning zone 91, 92 at an elevated temperature. The efficiency of energy transfer to a fluid in the cleaning zone 91, 92 is improved by the increased temperature difference between the temperature of the working medium 81 and the temperature of the fluid in the cleaning zone 91, 92. The heat pump 40 has, for example, a compressor 41, a throttle valve 42, and an expansion valve 43.

[0037] The working fluid 81 absorbs heat from the condensation enthalpy of the water vapor. The energy stored in the water vapor (evaporation enthalpy) is relatively high and can be recovered as condensation enthalpy.

[0038] To absorb the heat from the air stream 15, a first heat exchanger 10 through which the working medium 81 flows is provided in the cooling zone 93. A further heat exchanger 30 is provided here to absorb heat energy from the air or liquid in a further inner region of the cooling zone 93, near still-hot containers.

[0039] In addition, at least one second heat exchanger 60 through which the working medium flows is provided in the cleaning zone 91, 92 to supply heat from the working medium 15 to the cleaning zone 91, 92. The heat exchanger 60 heats, for example, spray water for pre-cleaning in the pre-treatment zone 91. Thus, a circuit of the working medium 81 is provided to absorb the heat at one point 10 and release it again at another point 60, without requiring direct contact between the working medium 81 and another fluid.

[0040] In this embodiment, a heat exchanger 50 is provided, merely by way of example, which heats a fluid in the main cleaning zone 92 upstream of the working medium 81. The temperature of the working medium 81 at the heat exchanger 50 is higher than at the downstream heat exchanger 60 because energy has already been extracted from the working medium 81.

[0041] Here, also purely by way of example, a further heat exchanger 30 is provided to absorb thermal energy from the cooling zone 93 in the working medium 81. This leads to further energy recovery.

[0042] In the container cleaning device 100, the absorbed heat can thus be supplied to heat at least one cleaning fluid in the cleaning zone 91, 92. In particular, the absorbed heat can be supplied to a cleaning fluid in a pretreatment zone 91 or heating zone 91 for the containers in the cleaning zone 91, 92. This is advantageous because energy is required for heating at these locations.

[0043] Fig. 2 shows a second embodiment of the container cleaning device 200 according to the invention.

[0044] This second embodiment of the container cleaning device 200 essentially corresponds to the first embodiment of the container cleaning device 100, wherein the same reference numerals are used for the same elements.

[0045] The air flow 15 runs at least partially along a transport direction of the containers in the cooling zone and passes through the heat exchanger 10 due to the suction by the fan 20.

[0046] The containers are cooled along the transport direction from a first, higher temperature to a second, lower temperature. The air stream 15, which has been cooled by the heat absorbed by the working medium 81, is then directed counter to the transport direction of the containers and supplied to the containers at the first temperature. For this purpose, at least one channel 16 is provided for directing the cooled air stream 15 counter to the transport direction of the containers. In this way, cooled air is supplied to the containers to be cooled.

[0047] Fig. 3 shows a third embodiment of the container cleaning device 300 according to the invention.

[0048] This third embodiment of the container cleaning device 300 essentially corresponds to the second embodiment of the container cleaning device 200, wherein the same reference numerals are used for the same elements.

[0049] The difference here is that downstream of heat exchanger 10 and upstream of heat exchanger 30, a further heat exchanger 51 is provided, with which thermal energy from wastewater of the pre-treatment zone 91 is transferred to the working medium 81 and recovered. In this embodiment, for example, the heat exchanger 50 of the first and second embodiments is omitted, and the working medium 81, at a temperature increased by the heat pump, is simply passed through the heat exchanger 60 of the pre-treatment zone 91 to transfer thermal energy to a pre-treatment fluid there.

[0050] The illustrated embodiments are merely exemplary and the full scope of the present invention is defined by the appended claims.

Claims

1. Container cleaning device (100, 200, 300), wherein the containers are in particular bottles, comprising: a cleaning zone (91, 92) for cleaning the containers; a cooling zone (93) for cooling the containers, wherein an air stream (15) laden with water vapor can be generated; and a heat transport device (80) with a working medium (81) for absorbing heat from the water vapor of the air stream (15) and for supplying absorbed heat to the cleaning zone (91, 92).

2. Container cleaning device (100, 200, 300) according to claim 1, wherein the heat transport device (80) comprises a heat pump (40) for increasing the temperature of the working medium (81) after absorbing heat from the water vapor of the air stream (15) and before supplying absorbed heat to the cleaning zone (91, 92).

3. Container cleaning device (100, 200, 300) according to claim 1 or 2, wherein the working medium (81) absorbs heat from condensation enthalpy of the water vapor.

4. Container cleaning device (100, 200, 300) according to one of claims 1 to 3, wherein at least one first heat exchanger (10) through which the working medium (81) flows is provided in the cooling zone (93) to absorb the heat from the air flow (15), and wherein at least one second heat exchanger (50, 60) through which the working medium (81) flows is provided in the cleaning zone (91, 92) to supply heat from the working medium (81) to the cleaning zone (91, 92).

5. Container cleaning device (100, 200, 300) according to claim 4, wherein at least one further heat exchanger (30, 51) is provided to absorb thermal energy from the cooling zone (93) and / or from waste water of the cleaning zone (91, 92) in the working medium (81).

6. Container cleaning device (100, 200, 300) according to one of claims 1 to 5, wherein absorbed heat can be supplied for heating at least one cleaning liquid in the cleaning zone (91, 92), in particular in a pretreatment zone (91) or warm-up zone (91) for the containers in the cleaning zone (91, 92).

7. Container cleaning device (100, 200, 300) according to one of claims 1 to 6, wherein the air flow (15) runs at least partially along a transport direction of the containers in the cooling zone (93).

8. Container cleaning device (100, 200, 300) according to claim 7, wherein the containers can be cooled along the transport direction from a first, higher to a second, lower temperature, and wherein the air flow (15) which has been cooled by the heat absorbed by the working medium (81) can be directed counter to the transport direction of the containers and can be supplied to the containers at the first temperature.

9. Container cleaning device (100, 200, 300) according to claim 8, wherein at least one channel (16) is provided for guiding the cooled air flow (15) against the transport direction of the containers.

10. A method for cleaning containers, in particular bottles, comprising the steps of: cleaning the containers in a cleaning zone (91, 92); cooling the containers in a cooling zone (93), wherein an air stream (15) laden with water vapor is generated; and absorbing heat from the water vapor of the air stream (15) into a working medium (81) and supplying absorbed heat from the working medium (81) to the cleaning zone (91, 92) by means of a heat transport device (80), wherein the heat is absorbed in particular from condensation enthalpy of the water vapor.

11. The method according to claim 10, comprising the further step of: increasing the temperature of the working medium after absorbing heat from the water vapor of the air stream (15) and before supplying absorbed heat to the cleaning zone (91, 92) with a heat pump (40).

12. The method according to claim 10 or 11, comprising the further step of: cooling the containers along a transport direction of the containers from a first, higher to a second, lower temperature.

13. The method according to claim 12, comprising the further steps of: directing the air stream (15) cooled by the heat absorbed by the working medium (81) counter to the transport direction of the containers; and supplying the cooled air stream (15) to the containers at the first temperature.

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