Patent Application
20120006817
The present application claims the benefit of priority of German Application No. 102010031047.6, filed Jul. 7, 2011. The entire text of the priority application is incorporated herein by reference in its entirety.
The disclosure relates to a device for tempering a mixture of a solid and a liquid phase, particularly a liquid containing fruit particles, of the kind explained in the introductory portion of Claim 1.
Such a device is known from DE 39 30 934 A1. The known device contains a container that is heated via its wall, into which container the product portions to be processed, for example, fruit particles and juice, but also water, sugar, powder or the like, are introduced. The bottom side of the container is given an outlet of a circulation line that leads back into the upper area of the container via a heat exchanger. The container is likewise heated. A stirring mechanism that works against stationary arms rotates inside the container, whereby these arms extend from the container inner wall inwards in the direction of the stirring mechanism. The stirring mechanism is operated such that gravity separation takes place, whereby the liquid phase tends to collect on the bottom of the container and the solid components float. In this way, the liquid phase is predominantly drawn off from the bottom of the container and sent into the heat exchanger via a pump, whereby this heat exchanger further heats the liquid phase. The heated liquid subsequently ends up back in the container where it runs onto the floating fruit particles from above, as a result of which these floating fruit particles are likewise heated.
Both the stirring mechanisms and the direct heating at the container wall represent a large load, however, particularly for sensitive products, and impair the quality.
One aspect of the disclosure is developing a device of the aforementioned type in a manner that is gentler on the product.
By means of the development according to the disclosure, a separation of the liquid phase or a great portion thereof is achieved that is substantially gentler on the product, whereby the liquid phase or a great portion thereof is then brought to the desired temperature without problems and returned again without a need for mechanical loading of the solid phase by the stirring mechanism used in the state of the art.
The barrier is selected according to the type and consistency of the solid phase and is formed as a sieve in the simplest case.
In order to create and maintain sufficient extraction space for the liquid phase, the barrier is preferably formed as an inner container and arranged at a distance from the wall of the container.
The confluence of the tempered liquid phase into the container takes place from below and in that area of the container in which the solid phase is also located. This achieves a fast and deep mixing, so that the temperature in the container homogenizes very quickly.
The temperature equalization inside the container can be further improved if the introduction of the tempered liquid phase takes place via a nozzle and consequently at a higher speed.
If the confluence takes place from the bottom to the top, the homogenization of the temperature is further improved and accelerated.
The container according to the disclosure can preferably also be used in order to remove harmful gases, such as atmospheric oxygen, for example, from the mixture located in the container if a degassing device is provided.
A device for creating positive pressure in the container allows the container to be emptied without the use of a pump, which frees the solid phase from a further mechanical load.
An embodiment of the disclosure is explained in more detail in the following drawing, which depicts the tempering device in schematic format.
The drawing shows a device 1 according to the disclosure that is formed in the embodiment shown for heating a mixture of a solid phase in the form of fruit particles and a liquid phase in the form of fruit juice or other liquids. The device according to the disclosure can, however, also be used for cooling the cited mixture or for tempering other mixtures that need to be handled carefully.
The mixture can, for example, contain fruit particles in the form of pieces and/or fibers and/or cells; the liquids are present in the form of juice, tea, sugared water or the like.
The device 1 contains a container 2 into which the components of the mixture are fed via a filling opening 3 in the upper area, whereby this container 2 contains an extraction point 4 at the deepest point through which the tempered mixture is drawn off.
A circulation line 5 connects the container 2 to a heat exchanger 6 that is selected according to the product to be heated and that is preferably a plate heat exchanger. A pump 7 is furthermore connected in the circulation line 5. The circulation line 5 leaves the container 2 via an exit point 5a and enters into the container again via an entry point 5b.
The exit point 5a of the circulation line 5 is separated from the interior of the container 2 by a barrier 8 that is formed such that only or predominantly the liquid phase enters into the circulation line 5 and consequently into the heat exchanger 6 and the pump 7. In this way, it is ensured that the components of the solid phase are not excessively mechanically or thermally loaded.
The manner of the barrier 8 is adapted to the solid phase that is to be held back, such as for example, its particle size and/or its consistency and/or its dimensional distribution (cells, fibers or pieces), so that the best possible retention effect can be achieved. In the simplest case, which is sufficient in the majority of cases, the barrier 8 is formed as a sieve with an appropriate hole size. The barrier 8 can, however, also be a filter material or a membrane. The barrier 8 is preferably mechanically stiff, or stretched to be mechanically stiff, and is keep at a sufficient distance A from the exit point 5a, which distance counteracts clogging. The barrier 8 is preferably formed as an inner container that runs coaxially to the container 2 and that is at a distance A from the same on all sides so that a collecting space 9 for the liquid phase forms between the barrier 8 and container 2. The barrier 8 preferably spans the entire area of the container 2 taken up by the mixture under the outlet of the filling opening 3 and of the extraction point 4 preferably at least up to the intended maximum filling level.
The exit point 5a of the circulation line 5 lies in the collecting space 9 and is located as close as possible to the extraction point 4 so that the liquid phase can also be drawn off when the filling level in the container 2 is low.
The entry point 5b of the circulation line 5 into the container 2 lies outside the collecting space 9 in that area in which the solid phase that has been separated out is located. The entry point 5b points upwards and is preferably given a nozzle 10 by means of which the tempered liquid phase is injected out of the heat exchanger 6 into the solid phase held back by the barrier 8. Due to the introduction in the lower area of the container 2, just above the extraction point 4 and essentially centred in the container 2, the formation of bubbles or foaming due to the injection is also avoided. This approach also achieves good thermal distribution and the heat transfer between the heated (cooled) liquid phase is improved on its way up to the solid phase.
The container 2 can furthermore be provided with a degassing device 11 and/or with a device 12 for creating positive pressure in the container 2. For degassing, particularly for removing dissolved oxygen from the mixture/liquid phase, the interior of the container 2 can be set to negative pressure during or outside of the tempering process by the degassing device 11.
To create positive pressure in order, for example, to empty the container 2 via the extraction point 4 in the gentlest possible manner, the container 2 can be set to positive pressure via the device 12 so that the container contents are pressed through the extraction point 4.
Both devices 11, 12 preferably engage in the upper area of the container 2, above the maximum filling level.
Although the above described, discontinuous process (batch process) is preferred, the container can easily also be designed for continuous operation.
In practical application, preferably a plurality of the above-described devices 1 are connected next to one another in parallel for effective operation and, for example, provided with a shared feed of the raw materials and a collecting line connected to all extraction points for withdrawing the tempered mixture. Furthermore, suitable cleaning devices and cleaning lines can be provided for cleaning at the end of operation or during operation.
In modification of the described and drawn embodiment, the device according to the disclosure can also be used for other mixed solid/liquid products that require especially careful handling of the solid phase. The device can be used both for heating and for cooling. Furthermore, additional filling openings or filling devices can be provided in order to add, for example, powder or other products, where applicable, also exactly dosed.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102010031047.6 | Jul 2010 | DE | national |
