Patent Application
20120312419
This application claims priority to German Patent Application No. DE 10 2011 077 375.4, filed Jun. 10, 2011, which is hereby incorporated by reference herein in its entirety.
The invention relates to a method for the hot filling of liquids, in particular juices, with a flash pasteuriser, which comprises a first heat exchanger, a filling station for filling the liquids into containers, for example bottles, and a cooling tunnel, which comprises a plurality of cooling cells, for cooling the filled containers by means of a cooling liquid, for example water, and also relates to an appropriate device for implementing the method.
In the state of the art it is known that liquids, in particular beverages or similar items containing juice, are heated before filling and are then filled warm/hot. The hot filling here ensures the sterilisation of the container and furthermore it simultaneously provides pasteurization of the product, say the beverage. After filling the liquid into the containers the products in the containers, which are typically closed, are cooled to at least ambient temperature or a desired storage temperature for improved handling and also for storage purposes.
To heat the juice typically vapour is used, for example steam, which is passed through a heat exchanger, thus transferring the heat from the steam to the product to be warmed/preheated, i.e. the beverage juice. Then, for the purposes of cooling typically a cooling tower and/or a refrigerating plant is employed.
For example, the liquid to be heated can be passed at approximately room temperature into the heat exchanger and is heated therein to temperatures of 80-90° C. Then the filling into containers typically follows. For cooling the containers filled with the product typically a cooling section such as say a cooling tunnel is used which is connected to a cooling tower. In the simplest case the thermal energy present in the containers with the filled, still hot liquid is dissipated into the surroundings. This energy is then lost from the system.
With regard to an at least partial recovery of the heat present in the liquid in the containers, in the state of the art it is known to employ heat exchangers. The cooling water used during cooling is heated due to the cooling process. A heat exchanger can extract thermal energy from the cooling water heated in this way, so that it can be used again for preheating. For example, DE 103 51 689 A1 shows the return of process liquid for the purpose of using the heat from the cooling liquid with regard to preheating. Here one problem is however that a heat exchanger can only transfer certain, suitable energies, so that the heated cooling water must attain a certain temperature before it can be used for heat transfer to other liquids.
DE 10 2007 003 976 A1 also describes a pasteurizing device with an integrated heat pump, whereby a pasteurizing device comprises a plurality of the same type of pasteurizing zones or pasteurizing segments, whereby thermal energy can be fed from a colder segment of the pasteurizing device to a hotter segment of the pasteurizing device. In this respect exclusively filled, closed containers are treated in the pasteurizing device. Here, the heat pump is integrated into the pasteurizing device, by means of which the configuration and complexity of the pasteurizing device are increased.
In view of the above mentioned problems and the discussed state of the art, an aspect of the present invention is to provide a device for the hot filling of liquids with an efficient thermal recovery which is also robust and easy to operate.
In an embodiment, the present invention provides a method for hot filling of liquids using a flash pasteurizer including a first heat exchanger, a filling station and a cooling tunnel including a plurality of cooling cells. The liquids are filled into containers in the filling station. The filled containers are cooled in the cooling tunnel using a cooling liquid. The liquids are heated before being filled into the containers, by feeding thermal energy from the cooling liquid that was heated during the cooling of the filled containers to the flash pasteurizer using a separate heat pump.
Exemplary embodiments of the present invention are described in more detail below with reference to the drawings, in which:
In an embodiment, the invention provides a method for the hot filling of liquids, in particular juices, with a flash pasteuriser, which comprises a first heat exchanger, a filling station for filling the liquids into containers, for example bottles, and a cooling tunnel, which comprises a plurality of cooling cells, for cooling the filled containers by means of a cooling liquid, for example water, whereby the liquids are heated in the flash pasteuriser before filling into containers in the filling station, in that thermal energy from the cooling liquid from the cooling tunnel heated during the cooling process is passed to the flash pasteuriser by means of a separate heat pump.
In the method the liquid to be filled, the product, for example beverage juice, is heated in the flash pasteuriser and namely already before filling. For this purpose the thermal energy from the cooling liquid, which heats up during the cooling process in the cooling cells of the cooling tunnel, is passed to the flash pasteuriser by means of the separate heat pump. In this way it is no longer necessary to heat the liquid to be heated up with steam. Consequently, a significant simplification of the device is achieved, because the steam heating device, feed line and discharge line for the steam can be omitted. Furthermore, it is no longer necessary to achieve a certain temperature level of the cooling liquid before it then flows through a heat exchanger in order to provide a suitable thermal transfer in the heat exchanger. In this way the degree of utilisation of the recovery is increased. The performance figure, COP (Coefficient of Performance), of the heat pump is here noticeably better than when using a heat exchanger. Here, the heat pump facilitates both cooling/heating for low costs. The costs essentially arise with regard to the electrical power consumed, which can be used for the operation of the heat pump.
In the method as described above, the thermal energy passed from the heat pump to the liquids by means of the first heat exchanger can contribute to the heating thereof. Consequently, the thermal energy fed from the heat pump, for example with the aid of a suitable liquid, such as water, can be transferred in the first heat exchanger to the liquid to be heated. After the heat exchange the liquid made cooler by the heat exchange can now be passed back to the heat pump.
In the method as described above, the heating of the liquids can take place completely by the thermal energy fed by means of the heat pump. The heat pump and the thermal energy taken from the cooling cells provide the heating of the product.
In a device according to an embodiment of the invention as described above the preheating of the liquids to be filled, for example, beverage juices, can take place completely by the thermal energy fed by means of the heat pump. That is, with the aid of the thermal energy extracted from the cooling tunnel and the heat pump and the electrical energy supplied to the heat pump, the heating of the liquids can take place completely before the filling without additional heating stages being required.
In the method as described above a second heat exchanger can be provided additionally in series with the heat pump for heating the liquids before filling such that the heated cooling liquid passes from the cooling tunnel to the second heat exchanger and thereafter to the heat pump, so that at least one part of the thermal energy of the heated cooling liquid can be initially transferred by means of the second heat exchanger to the liquid to be heated and thereafter at least one further part of the thermal energy can be transferred by means of the heat pump to the flash pasteuriser for further heating of the liquids.
With regard to the heating of the product before filling, the second heat exchanger can be provided in series with a heat pump. With regard to the heating of liquids, the series connection of the second heat exchanger to the heat pump in particular facilitates an increase in the temperature level in the heat pump and therefore also an improvement in the performance figure of the heat pump. In this respect, typically two steps occur in the heating of the liquid to be filled—the heat transfer by means of the second heat exchanger in particular for directly transferable thermal energies from the cooling tunnel to the liquid and then the increase of the energy level to the specified temperature for the preheating of the liquid, i.e. of the product, with the aid of the heat pump.
A second heat exchanger can be provided additionally in parallel with the heat pump for heating the liquids before filling such that at least part of the heated cooling liquid passes from the cooling tunnel to the second heat exchanger and at least a further part of the heated cooling liquid passes from the cooling tunnel to the heat pump, so that at least one part of the thermal energy of the heated cooling liquid can be transferred by means of the second heat exchanger to the liquid to be heated and at least one further part of the thermal energy can be transferred by means of the heat pump to the flash pasteuriser for further heating of the liquids.
With regard to the heating of the product before filling, the second heat exchanger can be provided in parallel to the heat pump. According to the parallel configuration of the heat pump and the second heat exchanger with regard to the heating of the product, a first cascade of cooling cells can, for example, be used for direct thermal transfer through the second heat exchanger. This cooling liquid is for example returned to the cooling cells after the heat exchange in the second heat exchanger. A second, parallel cascade of cooling cells is for example connected to the heat pump, for example additionally with the aid of a simple pump, whereby the energy level of the thermal energy of the second cascade can be increased so that this energy level for heating the liquids to be filled can be raised to the desired filling temperature.
In the method as described above the part of the heated cooling liquid, which passes to the second heat exchanger, can be hotter than the part of the heated cooling liquid, which passes to the heat pump.
For example, the temperature in the group of the first cooling cells, which are typically arranged sequentially, is higher than in the group of the second cooling cells, which are similarly typically arranged sequentially. Due to the parallel configuration of the second heat exchanger corresponding to the first cascade and of the heat pump corresponding to the second cascade a still higher energy level and therefore a higher performance figure of the heat pump can be achieved. The control of the device according to the invention as described above can for example be implemented with a suitable control unit, such as a computer.
The invention also comprises a device for implementing the method for the hot filling of liquids as described above.
In a device according to an embodiment of the invention the flash pasteuriser, filling station and cooling tunnel can each be formed separately. Each of these elements can therefore be formed separately from the other elements. The elements can be connected by suitable conveyor and/or transport elements, for example pipes for the transport of products or other liquids, which can act as auxiliary liquids for the transfer of heat, as well as conveyor belts or a transport facility for containers.
In the device according to an embodiment of the invention the first heat exchanger of the flash pasteuriser as described above can comprise a plate heat exchanger, PHE, or a shell-and-tube heat exchanger, STHE. That is, currently available types of heat exchanger can be used to transfer the thermal energy supplied by the heat pump to the liquid to be heated. Thus, the heat transfer of the liquid to be heated in the flash pasteuriser is typically decoupled from the filling process, which typically occurs after heating, and the cooling process which follows.
The heat pump used in the device according to an embodiment of the invention can comprise for example a compression heat pump, for example an electrically driven compression heat pump, an ammonia heat pump or a heat pump with the transcritical CO2 process. That is, currently available types of heat pump can be used, in particular those in which ammonia or CO2 are used as coolant. The latter enables the use of particularly energy efficient heat pumps, whereby at the same time coolant such as nitrogen or halogen alkanes can be dispensed with, whereby the latter may possibly be undesirable for filling systems and halogen alkanes furthermore may not be desirable due to their property as climate-damaging gases.
The heat pump of a device according to an embodiment of the invention, as described above, can typically be provided between one of the cooling cells of the cooling tunnel and the first heat exchanger of the flash pasteuriser. The heat pump can therefore be provided between the multi-cell cooling tunnel and the heat exchanger. Here for example, the heated coolant/liquid from the cooling tunnel can be pumped to the heat pump by means of a simple pump. After the heat exchange the now cooler liquid is returned to the cooling tunnel, for example again with an additional pump.
In a device according to an embodiment of the invention, as described above, the cooling cells of the cooling tunnel are for example joined together such that cooling liquid from one cooling cell can be pumped into one or a plurality of neighbouring cooling cells, for example in particular from a colder cooling cell to a hotter cooling cell. After filling, the filled and closed containers pass through the cooling tunnel, i.e. a cooling section with a plurality of similar or the same type of cooling cells. The cooling cells differ typically due to the temperatures which respectively prevail in a cooling cell.
Each of the cooling cells contains typically a sprinkling system or spray device to spray the containers with cooling liquid. The containers to be cooled are also, for example, sprinkled with water. In this way a heat exchange between the cooling water and the liquid filled into the containers can occur.
The cooling liquid is for example collected and namely separately for each cooling cell. Typically there is a temperature gradient from the first to the last of the plurality of cooling cells, whereby typically the first cooling cell is the hottest and the last cooling cell is the coldest cooling cell. The reservoirs/collecting basins for the cooling liquid/water of the cooling cells are for example joined together so that cooling water from one cooling cell can be pumped into an adjacent cooling cell where it can be used again optionally for sprinkling.
In a device according to an embodiment of the invention a heat pump can be provided between the cooling cell with the highest temperature of the heated coolant and the first heat exchanger. Typically this is the first cooling cell of the cooling tunnel.
In device according to an embodiment of the invention and with the use of two heat exchangers the liquid to be heated flows to the first and to the second heat exchanger. The two heat exchangers are therefore provided in series in the flash pasteuriser.
Therefore, use of a heat pump is required which can be provided separately from the cooling tunnel, separately from the filling station and the flash pasteuriser and offers the possibility of an efficient and high energy recovery within the scope of the product preheating. The use of a heat pump in parallel or series configuration with a heat exchanger facilitates a further increase in efficiency and at the same time an improvement in the performance figure of the heat pump.
The product is passed through a line 11 to a further heat exchanger 12, which essentially acts as a flash pasteuriser. The heat exchanger/flash pasteuriser 12 has vapour, typically steam, passing through it, which transfers its thermal energy to the product flowing through the flash pasteuriser 12. The vapour is passed to the heat exchanger/flash pasteuriser 12 with the aid of the line 13 and the vapour, now cooler after the heat exchange, is led away from the flash pasteuriser 12 through the line 14. Here, the vapour used in this process, for example steam, can be heated by conventional means.
The heating of the product in the flash pasteuriser 12 can take place up to temperatures of 80-90° C., depending on the temperature required for the product. The heated product can be transported to a filling station 15 through suitable feed lines 16, which are shown purely schematically with an arrow, but which may be located spatially separate from the flash pasteuriser 12. The filling station 15 can comprise a suitable device for the hot filling of the product, i.e. the heated liquid, in containers 25, for example bottles, as they are known in the state of the art. Within the device 15 the containers 25 are typically closed and then passed by means of a transport device 17, which again is indicated purely schematically as an arrow, to the cooling section/cooling tunnel 20.
The cooling tunnel/cooling section 20 consists of a plurality of cooling cells. In
The cooling cells furthermore comprise sprinkling systems 21.1, 21.2, 21.3, 21.4, 21.5 and 21.6, which are illustrated schematically. The said sprinkling systems are used to sprinkle the closed containers 25 to be cooled with a cooling liquid, for example water, in order to cool them. The cooling water is passed through the cooling water feed lines 25.1, 25.2, 25.3, 25.4, 25.5 and 25.6 to the sprinkling devices. Here, the coolant used can be collected by coolant basins, which are designated by the reference numerals 23.1, 23.2, 23.3, 23.4, 23.5 and 23.6. From the designated coolant basins 23.1, 23.2, 23.3, 23.4, 23.5 and 23.6 at least part of the cooling water can be used again with the aid of pumps 22.1, 22.2, 22.3, 22.4, 22.5 and 22.6 for sprinkling. Furthermore, fresh, for example cooler coolant, say water, can also be fed in (not illustrated here). Furthermore, heated cooling water which has dissipated part of its heat in the product in the heat exchanger 3 and which subsequently has been cooled again by means of the cooling tower 7 can again be passed through a feed line 8, a conventional pump 9 and a feed line 10 to the cooling tunnel 20.
As already described in
In contrast to
The heat pump 30 comprises an element 34 for the heat dissipation, an element 31 for heat absorption, and a throttle 33 and a compressor 32. Within the heat pump the circulation paths are shown by arrows 35 and 36. The temperatures on the right, cooler side of the heat pumps are designated with TC2 and TC1. Here TC1 can be say 16° C., but other temperatures are also possible depending on the machine ratings, machine length, insulation, etc. Similarly, the temperature TC2 can be say 30 to 32° C., but similarly other temperatures are also possible. For example, the temperature T1 can be say 28° C., the temperature T2 say 96° C., the temperature T3 say 28° C. and the temperature T4 say 27° C. Here, these temperature figures should be regarded as purely exemplary and similarly other temperature figures are also possible depending on the rating of the heat pump 30, its performance figure, the recovered electrical energy and other parameters according to the rating of the machines.
In
In the device according to the invention in
After being heated and passing through the heat exchanger 62, the product is passed through a suitable line system 63 to the filling station 15. The filling station 15 can be a filling station, as has been already described with reference to
After heating in the heat exchanger 60, the heated product is passed to the heat exchanger 62. The cooling liquid, which has a slightly cooled temperature level through use in the heat exchanger 60, is passed from the heat exchanger 60 by means of the feed line 67 to the heat pump 50.
The heat pump 50 comprises the heat pump element 51 for heat absorption, heat pump element 54 for heat dissipation, as well as the compressor 52 and the throttle 53. The reference numerals 55 and 56 designate the direction of flow within the heat pump 50. A suitable liquid for the heat transfer is passed to the first heat exchanger 62 from the element 54 of the heat pump 50 through the feed line 64, whereby the product can be heated to the desired target temperature. After heating in the heat exchanger 62 the cooled liquid is passed through the feed line 65 back to the heat pump 50. Here it is passed into the element 54 of the heat pump 50. The cooling liquid, cooled after passing through the element 51, is passed back to the cooling tunnel 20 through the line 10. Here, as illustrated in
The cooling section 70 comprises, as exemplarily illustrated, six cooling cells 70.1, 70.2, 70.3, 70.4, 70.5 and 70.6. These cooling cells comprise sprinkling facilities/systems 71.1, 71.2, 71.3, 71.4, 71.5 and 71.6. These sprinkling systems 71.1, 71.2, 71.3, 71.4, 71.5 and 71.6, which are illustrated purely schematically as having two arms, receive the coolant, say water, for sprinkling through lines 75.1, 75.2, 75.3, 75.4, 75.5 and 75.6. The cooling water dripping or draining from the containers 25 after sprinkling is collected in the respective collecting containers 73.1, 73.2, 73.3, 73.4, 73.5 and 73.6, which can be open, in the respective cooling cells 70.1, 70.2, 70.3, 70.4, 70.5 and 70.6. The collected cooling water can at least be partially used by the pumps 72.1, 72.2, 72.3, 72.4, 72.5 and 72.6 for sprinkling. Here, similarly cooler freshwater can be used from other feed-line sources—not shown here. Furthermore, cooler water, which flows back from a heat pump 80, can be passed to the cooling cells 70.1, 70.2, 70.3, 70.4, 70.5 and 70.6, as is described in the following.
In
After heating to the target temperature, the product is fed to a filling station 15 through a line 93 which is drawn purely schematically. The filling station 15 corresponds to the filling stations already outlined above in connection with
In the embodiment illustrated in
For the devices illustrated in
It is self-evident that the illustrated devices can also be analogously used for a specified cooling of products to lower temperatures.
It is self-evident that the features mentioned in the above described embodiments are not restricted particularly to the combinations illustrated in the figures, but rather are also possible in other combinations.
While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2011 077 375.4 | Jun 2011 | DE | national |
