EP3269460B1 - Bottle cleaning device and method for a process water circuit using the bottle cleaning device - Google Patents

Description

The invention relates to a bottle cleaning device according to claim 1 and a method for a process water circuit using the bottle cleaning device according to claim 7.

State of the art

DE 32 05 956 A1 discloses a device for bottle cleaning, in which the water flowing out of the first preheating device is cooled in a recooling device by means of a heat exchanger and fed to the waste water, and in which the water thus heated in the recooling device is cooled by means of a heat pump and the recooling device is led to it. The lye of the second preheating device is heated by means of the heat pump. The heat and fresh water consumption of this device is thus low. This is due to the fact that the energy circuit for heating and cooling is closed and only the heat loss has to be replaced by energy supply.

DE 24 54 100 discloses a container cleaning machine in which the containers with conveyors are successively transported through several machine stages, in which they are treated with immersion or spraying with cleaning liquids, only a middle stage being externally heated and the treatment temperature in the container transport direction gradually increasing before this middle stage and behind it gradually falls off.

task

The object of the invention is to optimize a bottle cleaning device with regard to its fresh water consumption.

solution

The object is achieved by the bottle cleaning device according to claim 1 and the method according to claim 7. Preferred embodiments and developments are disclosed in the subclaims.

A bottle cleaning device comprises a fresh water reservoir, which is connected to a recycling water reservoir, which is connected to a cold water reservoir, which is connected to a second hot water reservoir, which is connected to a first hot water reservoir, which is connected to a post-lye reservoir, which is connected to a detergent solution bath or to a pretreatment zone in such a way that water is produced the fresh water reservoir into the recycle water reservoir, from the recycle water reservoir into the cold water reservoir, from the cold water reservoir into the second hot water reservoir, from the second hot water reservoir into the first hot water reservoir, from the first hot water reservoir for refilling or diluting into the replenishment reserve Lye bath or can enter the pretreatment zone. The bottle cleaning device also includes the recycle water reservoir, the cold water reservoir, the second hot water reservoir, the first hot water reservoir, the after-lye reservoir and the lye bath. In addition, the bottle cleaning device comprises a mixing valve which is connected to the first hot water reservoir and the cold water reservoir via feed lines and is designed to mix water supplied from the first hot water reservoir and the cold water reservoir to mixed water. The bottle cleaning device also comprises a first heat exchanger which is designed to cool the mixed water and at the same time heat up a first medium, a second heat exchanger which is designed to cool the first medium and at the same time heat up a second medium, and a third heat exchanger which does so is designed to cool down the second medium and at the same time heat up a third medium and a fourth heat exchanger which is designed to cool down the third medium and at the same time heat up alkali from the alkali bath. Furthermore, the bottle cleaning device comprises a return line which is designed to supply the mixed water cooled in the first heat exchanger to the recycling water reservoir.

When the water is passed from one stage of the cascade to a next stage, substances dissolved in the water of one stage can also pass along with the water. The proportion of these substances can, however, be reduced by filtering.

The first and second heat exchangers can be regarded as an intermediate circuit in which the first medium circulates and which is required for the two-stage high-temperature heat pump.

The two-stage high-temperature heat pump comprises the second and third heat exchangers in the first stage and the third and fourth heat exchangers in the second stage. The second heat exchanger of the first stage serves as an evaporator for the second medium and the third heat exchanger as a condenser for the second medium. In the second stage, the third heat exchanger serves as an evaporator for the third medium and the fourth heat exchanger as a condenser for the third medium.

The refrigerant R134a can be used for the second medium, since no high-temperature capability is required here. The refrigerant ÖKO 1 can be used for the third medium.

This bottle washer saves up to 30% in fresh water consumption as it allows water to be extracted from the washing process and treated, to cool and reintroduce the cleaning process as a fresh water replacement. The extracted water from the cold water reservoir and the first hot water reservoir has a temperature of about 50 ° C after mixing. In order to use this mixed water as a fresh water substitute, it must be cooled to around 15 ° C so that its temperature is roughly the same as that of the fresh water. The heat content of the branched-off water is high, and therefore a great cooling capacity has to be applied. The two-stage high-temperature heat pump described has proven to be the most suitable cooling.

The use of recycled water thus enables savings of around 30% in fresh water, and thus also a waste water quantity reduced by around 30%. By recycling the heat, energy can also be saved that would otherwise have to be used to heat the water. It is therefore possible to amortize such a modified bottle cleaning machine after a few years based on the current water, wastewater and energy costs.

The bottle cleaning device can further comprise a first compressor, in a first direction of flow of the second medium, after the second heat exchanger and a first expansion throttle, in the first direction of flow of the second medium, after the third heat exchanger, and also a second compressor, in a second direction of flow of the third Medium, after the third heat exchanger and a second expansion throttle, in the second flow direction of the third medium, after the fourth heat exchanger. The designations "first" and "second" flow direction are used in order to be able to clearly assign the respective flow direction to the respective (second or third) medium.

The first and second compressors as well as the first and second expansion throttles are also part of the two-stage high-temperature heat pump.

The medium, generally a refrigerant, which has been transferred from the liquid to the gaseous state in an evaporator, is sucked in by a compressor and compressed in the compressor to the pressure which is necessary to liquefy the medium. As the compressor compresses the vaporous medium from a low initial pressure to a high final pressure, the temperature of the medium rises, so that this medium can be used again to heat another medium.

The mixing valve can comprise a temperature-controlled servomotor. A temperature sensor at the outlet of the mixing valve can give a signal to a controller that regulates the servomotor, so that the volume flow of the water from the cold water reservoir and the Volume flow of water from the first hot water reservoir can be regulated and a desired mixing temperature can be achieved by regulating the mixing ratio.

The first compressor and / or the second compressor can each comprise a screw compressor. A screw compressor can work at very high pressures. For this purpose, two spiral rotors rotate in opposite directions of rotation. One rotor can have four convex teeth and the other rotor can have six concave teeth. If the rotors rotate against each other, small chambers are created which convey the gas in the screw compressor in one direction. There is suction on the suction side, which sucks in the gaseous medium, and ejection on the discharge side.

The first heat exchanger can comprise a plate heat exchanger. A plate heat exchanger achieves a very compact design through the construction of several corrugated plates, which are assembled alternately rotated by 180 °. This creates flow gaps through which the warm medium to be cooled and the medium to be heated are passed alternately. There is a large heat transfer area. With the counterflow heat exchanger, the medium runs on the primary side opposite to that on the secondary side. The temperature difference between the incoming and outgoing medium on an evaporator of the heat exchanger should only be between 5 and 7 K difference, otherwise the heat transfer coefficient will be smaller if the temperature difference between the incoming and outgoing medium is too large.

The second heat exchanger and / or the third heat exchanger and / or the fourth heat exchanger can each comprise a shell-and-tube heat exchanger. A tube bundle heat exchanger consists of a jacket and a tube bundle. One medium flows through the tube bundle of U-tubes on the primary side and another medium flows through the secondary side in the jacket.

A process for a process water circuit using a bottle cleaning device as described above or below comprises the following steps: branching off water from the cold reservoir and water from the first hot water reservoir and supplying this water to the mixing valve, mixing this water by means of the mixing valve with a temperature-controlled one Actuator, supplying the mixed water through the first filter to the first heat exchanger and cooling the mixed water in the first heat exchanger while heating a countercurrent first medium in the first heat exchanger and supplying the cooled mixed water via a second filter to the recycle water reservoir.

Subsequently, the heated first medium can be fed to the second heat exchanger and the first medium can be cooled in the second heat exchanger, and at the same time a countercurrent second medium can be heated in the second heat exchanger and the cooled first medium can be fed to the first heat exchanger. The first and the second medium can each circulate in a line system in the intermediate circuit or in the first stage of the two-stage high-temperature heat pump.

Then, feeding the heated second medium through the first compressor to a third heat exchanger and cooling the second medium in the third heat exchanger and simultaneously heating a countercurrent third medium in the third heat exchanger and feeding the cooled second medium via the first expansion throttle the second heat exchanger.

The heated third medium can then be fed to the fourth heat exchanger by the second compressor and the third medium can be cooled in the fourth heat exchanger. At the same time, countercurrent lye can be heated from the lye bath in the fourth heat exchanger, then the heated lye can be fed to the lye bath and the cooled third medium can be fed via the second expansion throttle to the third heat exchanger. The third medium can circulate in a line system in the second stage of the two-stage high-temperature heat pump. The lye can be led from the lye bath to the fourth heat exchanger and back to the lye bath by means of another line system.

In the method, fresh water can be fed into the bottle cleaning machine at the beginning in order to fill the cascade of successive water reservoirs. After filling with water and when the various water reservoirs have reached the required water temperatures, water from the cold reservoir and water from the first hot water reservoir can be branched off and then fed to the mixing valve.

Brief description of the figures

• Figur 1 ein Blockdiagramm eines Prozesswasserkreislaufs einer Flaschenreinigungsmaschine und
• Figur 2 ein Flussdiagramm eines Verfahrens für einen Prozesswasserkreislauf.

The attached figures represent examples of aspects of the invention for better understanding and illustration.

• Figure 1 a block diagram of a process water circuit of a bottle washer and
• Figure 2 a flowchart of a method for a process water cycle.

Detailed description of the figures

Figure 1 shows a block diagram of a process water circuit 1 of a bottle washing machine, which comprises a fresh water reservoir 2, a recycle water reservoir 3, a cold water reservoir 4, a second hot water reservoir 5, a first hot water reservoir 6, a post-alkali reservoir 7 and a caustic bath 8. Water is fed from the first hot water reservoir 6 to a pretreatment zone 9, which comprises a pre-soaking bath and spray devices.

Bottles to be cleaned can be fed to the bottle cleaning machine by means of a conveyor belt. After these bottles have been introduced into bottle cells of a bottle carrier, they are fed upside down to a pretreatment zone 9, in which there is first a residual emptying and then a pre-cleaning and heating of the bottles.

In the main treatment zone, the caustic bath 8 is provided at approximately 78-80 ° C., into which the bottles are placed. A plurality of soapy baths can also be provided. The labels detach from the bottles in the lye bath without dissolving. The detached labels are regularly removed from the lye bath 8 in order to keep its contamination low.

In the aftertreatment zone following the main treatment zone, the bottles are first of all with an after-liquor from the after-liquor reservoir 7 at about 60 ° C., then with water from the first hot water reservoir 6 at about 50 ° C., then with water from the second hot water reservoir 5 at about 40 ° C. , then treated with cold water from the cold reservoir 4 at about 30 ° C and finally with fresh water from the fresh water reservoir 2 at about 15 ° C. The sequential cooling minimizes tensions in the material of the bottles, and the bottles are also prepared for subsequent cold filling.

The cleaned bottles are then removed from the bottle cells of the bottle carrier and can be transported away with a delivery belt, for example to a filling device.

The direction of flow of the water in the bottle washer is opposite to the direction of transport of the bottles, i.e. from the aftertreatment zone to the main treatment zone and then to the pretreatment zone 9. The bottles in the pretreatment zone 9 are still comparatively heavily soiled and therefore do not have to be sprayed unnecessarily with fresh water, but can instead be sprayed with water that has already been used for other process steps and by means of a or more filters has been cleaned. Detached labels are also regularly removed from the caustic baths. The last spraying of the bottles before they leave the bottle washer must be done with fresh water, and therefore the bottle washer is filled with fresh water there.

The bottle washer is constructed in a cascade, so that the water fed in overflows from treatment zone to treatment zone and can therefore also be used there. Fresh water is preferably fed in at the beginning of the cascade.

A drain for a crate washer can be provided from the first water reservoir 6 so that the beverage crates do not have to be rinsed with fresh water. The container brewing machine can also be supplied with water by the bottle washing machine; for example, the water from a high pressure pre-injection of the pre-treatment zone 9 can be used.

If the after-liquor in the after-liquor reservoir 7 becomes too alkaline, it can be diluted with water from the first hot water reservoir 6. If the fill level in the lye bath 8 is too low, it can be refilled from the after-lye reservoir 7 by means of after-lye. If the lye 8 is too watered down, lye is replenished through a dosing station.

One consideration of saving resources in the bottle cleaning process is to remove water from the post-treatment of the bottle cleaning, to prepare it, to cool it and to feed it back into the process as a fresh water substitute. The extracted water must be cooled down from 50 ° C to 15 ° C so that its temperature corresponds approximately to the temperature of the fresh water used. The large amount of heat generated during cooling can be used to heat the hot alkaline baths.

However, the entire volume flow of fresh water should not be replaced by recycled water; for the present invention, it has been shown that about 30% of the original Fresh water consumption of the bottle washer can be recycled and fed into the cleaning process without there being any impairments. The water for reuse is withdrawn from the first hot water reservoir 6 and the cold water reservoir 4 and fed to a mixing valve 10 with a temperature-controlled servomotor. From there, the mixed water is passed through a first filter 11 and fed to a first heat exchanger 12 via a first inlet 13. The mixed water there has a temperature of T ₁ ^{acc. Water} = 50 ° C. In the first heat exchanger 12, a first medium with a temperature T ₁ ^M1 = 10-12 ° C. flows from a second inlet 15 in the opposite direction to the mixed water and leaves the first heat exchanger 12 after absorbing heat via a second outlet 16 with a temperature T ₂ ^M1 = 19 - 50 ° C. In order to obtain a predetermined temperature value of the temperature T ₂ ^M1 , the volume flow of the flowing first medium must be taken into account, among other things. At a temperature of T ₂ ^M1 = 19 ° C, the volume flow can be in a range of 140 m ³ per hour, at a temperature of T ₂ ^M1 = 50 ° C, the volume flow can be in a range of 25 m ³ per hour. The mixed water cooled in the first heat exchanger 12 leaves the first heat exchanger 12 via a first outlet 14 with a temperature of T ₂ ^{acc. Water} = 15 ° C. This cooled mixed water is passed through a second filter 17 and fed to the recycling water reservoir 3, so that this recycled water can be fed back into the cascade of the bottle washing machine, whereby the amount of fresh water that would otherwise be required can be reduced accordingly.

The first heat exchanger 12 is part of an intermediate circuit which is required for the two-stage high-temperature heat pump 38. The intermediate circuit comprises the first heat exchanger 12, a second heat exchanger 18 and a pump 19 which is provided for the transport of the first medium in the intermediate circuit and which is adjustable by means of a control valve and a pressure gauge. The first medium reaches the second heat exchanger 18 via a first inlet 20 at a temperature of T ₂ ^M1 = 19-50 °. In the second heat exchanger 18, a second medium with a temperature T ₁ ^{M2 flows} from a second inlet 22 in the opposite direction to the first medium. After cooling, the first medium leaves the second heat exchanger 18 via a first outlet 21 with a temperature of T ₁ ^M1 = 10-12 ° C.

The second medium leaves the second heat exchanger 18 after heating via a second outlet 23 with a temperature of T ₂ ^M2 . The second medium is passed through a first compressor 24 to increase its pressure and temperature to T ₃ ^M2 . The second medium then enters the third heat exchanger 25 via a first inlet 26 and leaves it again via a first outlet 27 at a temperature of T ₄ ^M2 . This third heat exchanger 25 serves as an evaporator for the second medium, and from there the condensed second medium arrives at the temperature T ₄ ^M2 . to a first expansion throttle 28. From there, the second medium with the temperature T ₁ ^{M2 is} fed back to the second heat exchanger 18 via the second inlet 22. The third heat exchanger 25 thus serves as a condenser for the second medium. The refrigerant R134a can be used as the second medium.

In the third heat exchanger 25, a third medium flows in the opposite direction to the second medium. The third medium enters the third heat exchanger 25 via a second inlet 29 with a temperature T ₁ ^M3 and leaves it again via a second outlet 30 with a temperature T ₂ ^M3 . From there, the third medium reaches a second compressor 31. After the third medium has been compressed, it reaches a fourth heat exchanger 32 at a temperature T ₃ ^M3 = 85 ° C. The compressed third medium is fed into the fourth heat exchanger via a first inlet 33 32 introduced, is liquefied in the fourth heat exchanger 32 and leaves this via a first outlet 34 with a temperature T ₄ ^M3 . From there the third medium reaches a second expansion throttle 35 and from there with the temperature T ₁ ^M3 to the third heat exchanger 25.

In the fourth heat exchanger 32, the liquor flows from the liquor reservoir 8 in the opposite direction to the third medium. The liquor reaches the fourth heat exchanger 32 at a temperature T ₁ ^liquor = 78-80 ° C. via a second inlet 36, where it takes heat from the third Medium and leaves the fourth heat exchanger 32 with a temperature T ₂ ^lye = 80-85 ° C again via a second outlet 37. From there, the lye is led back to the lye reservoir 8.

The third heat exchanger 25 thus serves as an evaporator for the third medium and the fourth heat exchanger 32 as a condenser for the third medium. The refrigerant ÖKO 1 can be used as the third medium.

The two-stage high-temperature heat pump 38 comprises the second heat exchanger 18, the third heat exchanger 25, the fourth heat exchanger 32, the first compressor 24, the second compressor 31, the first expansion throttle 28 and the second expansion throttle 35. Since the two-stage high-temperature heat pump 38 generally has different, circulating media and the volume flow in the respective circuits can be different and / or system conditions can be adapted, it is advantageous to specify 38 boundary conditions for the two-stage high-temperature heat pump, such as T ₁ ^lye = 78 - 80 ° C, T ₂ ^lye = 80 - 85 ° C and T ₁ ^M1 = 10 - 12 ° C, um then to be provided in accordance with properties of the second 18, the third 25 and the fourth heat exchanger 32, the first and the second compressor 31, the first 28 and the second expansion throttle 35.

Figure 2 shows a flow diagram of a method for a process water cycle. In order to start the process, in a first step 100 fresh water is first fed into the bottle cleaning machine in order to fill the cascade of successive water reservoirs. After filling with water and when the various water reservoirs have reached the required water temperatures, in a second step 101 water is branched off from the cold reservoir 4 and the first hot water reservoir 7 and fed to a mixing valve 10.

In a third step 102, this water of different temperatures is mixed by means of the mixing valve 10 with a temperature-controlled servomotor.

In a fourth step 103, the mixed water is fed to a first heat exchanger 12 via a first filter 11 and cooled in the first heat exchanger 12. At the same time, a counter-flowing first medium is heated in the first heat exchanger 12.

In a fifth step 104, the cooled mixed water is fed to a recycling water reservoir 2 via a second filter 17. The cooled, mixed water is then available to the cascade of the bottle washer again.

In a sixth step 105, the heated first medium is fed to a second heat exchanger 18, in which it is cooled. At the same time, a counter-flowing second medium is heated in the second heat exchanger 18. The cooled first medium is then fed back to the first heat exchanger 12.

In a seventh step 106, the heated second medium is fed through a first compressor 24 to a third heat exchanger 25, in which the second medium is cooled. At the same time, a counter-flowing third medium is heated in the third heat exchanger 25. The cooled second medium is fed back to the second heat exchanger 18 via a first expansion throttle 28.

In an eighth step 107, the heated third medium is fed through a second compressor 31 to a fourth heat exchanger 32 and cooled there. At the same time, countercurrent lye from the lye bath 8 is heated in the fourth heat exchanger and then fed back to the lye bath 8. The cooled third medium is fed back to the third heat exchanger 25 via a second expansion throttle 35.

Claims (11)

1. Bottle cleaning device comprising:

   - a fresh water reservoir (2) being connected with a recycle water reservoir (3), the recycle water reservoir (3) being connected with a cold water reservoir (4), the cold water reservoir (4) being connected with a second warm water reservoir (5), the second warm water reservoir (5) being connected with a first warm water reservoir (6), the first warm water reservoir (6) being connected with an post-lye reservoir (7), the post-lye reservoir (7) being connected with a lye bath (8) or with a pre-treatment zone (9) in such a way, respectively, that water from the fresh water reservoir (2) can pass into the recycle water reservoir (3), from the recycle water reservoir (3) in the cold water reservoir (4), from the cold water reservoir (4) in the second warm water reservoir (5), from the second warm water reservoir (5) in the first warm water reservoir (6), from the first warm water reservoir (6) for refilling or diluting in the post-lye reservoir (7) and from the post-lay reservoir (7) for refilling in the lye bath (8) or the pre-treatment zone (9),

   - mixing valve (10) being connected via feed pipes with the first warm water reservoir (6) and the cold water reservoir (4), and being adapted to mix water being infeed form the first warm water reservoir (6) and the cold water reservoir (4) to mixed water,

   - a first heat exchanger (12) being adapted to cool the mixed water and at the same time heat a first medium,

   - a second heat exchanger (18) being adapted to cool the first medium and at the same time heat a second medium,

   - a third heat exchanger (25) being adapted to cool the second medium and at the same time heat a third medium,

   - a fourth heat exchanger (32) being adapted to cool the third medium and at the same time heat lye of the lye bath (8) and

   - a return pipe being adapted to feed the mixed water that has been cooled in the first heat exchanger to the recycle water reservoir (3) .
2. Bottle cleaning device according to claim 1, further comprising:

   - a first condenser (24) being located in a first flow direction of the second medium after the second heat exchanger (18) and a first release choke (28) being located in the first flow direction of the second medium after the third heat exchanger (25) and

   - a second condenser (31) being located in a second flow direction of the third medium after the third heat exchanger (25) and a second release choke (35) being located in the second flow direction of the third medium after the fourth heat exchanger (32).
3. Bottle cleaning device according to claim 1 or 2, wherein the mixing valve (10) comprises a temperature controlled servomotor.
4. Bottle cleaning device according to one of claims 1 to 3, wherein the first condenser (24) and/or the second condenser (31) each comprise a screw compressor.
5. Bottle cleaning device according to one of claims 1 to 4, wherein the first heat exchanger (12) comprises a plate heat exchanger.
6. Bottle cleaning device according to one of claims 1 to 5, wherein the second heat exchanger (18) and/or the third heat exchanger (25) and/or the fourth heat exchanger (32) each comprise a tube bundle heat exchanger.
7. Method for a process water circuit using a bottle cleaning device according to one of claims 1 to 6 with the steps:

   - diverting (101) water from the cold water reservoir (4) and water from the first warm water reservoir (6) and infeeding (101) this water to the mixing valve (10),

   - mixing (102) this water by means of the mixing valve (10) with a temperature controlled servomotor,

   - infeeding (103) the mixed water via the first filter (11) to the first heat exchanger (12) and cooling (103) of the mixed water in the first heat exchanger (12) and at the same time heating (103) of a counter flowing first medium in the first heat exchanger (12) and

   - infeeding (104) of the cooled mixed water via a second filter (17) to the recycle water reservoir (3).
8. Method according to claim 7 with the further steps:

   - infeeding (105) the heated first medium to the second heat exchanger (18) and cooling (105) the first medium in the second heat exchanger (18) and at the same time heating (105) of a counterflowing second medium in the second heat exchanger (18) and infeeding (105) the cooled first medium to the first heat exchanger (12).
9. Method according to claim 8 with the further steps:

   - infeeding (106) the heated second medium via the first condenser (24) to the third heat exchanger (25) and cooling (106) the second medium in the third heat exchanger (25) and at the same time heating (106) the counterflowing third medium in the third heat exchanger (25) and infeeding (106) the cooled second medium via the first release choke (28) to the second heat exchanger (18).
10. Method according to claim 9 with the further steps:

    - infeeding (107) the heated third medium via the second condenser (31) to a fourth heat exchanger (32) and cooling (107) the third medium in the fourth heat exchanger (32) and at the same time heating (107) counterflowing lye of the lye bath (8) in the fourth heat exchanger, afterwards infeeding (107) of the heated lye to the lye bath (8), infeeding the cooled third medium via the second release choke (35) to the third heat exchanger (25).
11. Method according to one of claims 7 to 11, wherein in a first step (100) an infeed of fresh water in the bottle cleaning device takes place.

Images