AU2016350039B2

AU2016350039B2 - Method and device for controlling foaming in containers for liquids or foams and register system for such a device

Info

Publication number: AU2016350039B2
Application number: AU2016350039A
Authority: AU
Inventors: Hubert Assing; Helmut Buss; Ulrich ROLLE; Andreas Schmied; Uwe Schwenzow; Ludger Tacke; Dietrich Zimmermann
Original assignee: GEA TDS GmbH
Current assignee: GEA TDS GmbH
Priority date: 2015-11-03
Filing date: 2016-10-27
Publication date: 2019-12-19
Anticipated expiration: 2036-10-27
Also published as: CA3003758A1; AU2016350039A1; DK3370510T3; EP3370511B1; AU2016351211A1; NZ742195A; PL3370510T3; CA3004119A1; DE102015015056A1; WO2017076488A1; EP3370510B1; WO2017076491A1; DE102015015055A1; PL3370511T3; AU2016351211B2; DE102015015055B4; EP3370510A1; DK3370511T3; EP3370511A1; DE102015015056B4

Abstract

The invention relates to a method and to a device for controlling foaming in a liquid container (100) for liquids (P), in particular liquid foods such as milk, semi-skimmed milk, skimmed milk, or fruit juices, or in a foam container (200) for foams (S) that arise from the liquids (P) by decomposition, and to a register system (20) for such a device. The aim of the invention is for the method, the device for performing the method, and the register system to effectively control and limit foaming and prevent the growth of the foam beyond a tolerable amount while ensuring the sanitary and hygienic process-control requirements. This is aim achieved in respect of process engineering in a liquid container (100), inter alia in that the growing foam (S), beginning at a heating distance (h) from the free surface (N), first experiences heating from the liquid temperature (T3) to a heating temperature (T1) in the register system (20), which consists of a heating register (20.1) and a cooling register (20.2), and that the further growing heated foam (S), beginning at a cooling distance (k) from the first heating distance (h), then experiences cooling to a cooling temperature (T2) in the register system (20).

Description

Method and Device for Controlling Foaming in Containers for Liquids or Foams and

Register System for Such a Device

TECHNICAL FIELD

The disclosure relates to a method and a device for controlling foaming in a liquid container or in a foam container, as well as a register system for such a device. The liquids are preferably liquid foods such as milk, skimmed milk or fruit juices, but generally all foaming liquids are considered.

PRIOR ART

With liquids of the kind at issue, gas admixtures, in particular air admixtures with their constituent of air oxygen, are harmful in many regards, and they may frequently lead to undesirable foaming in the treatment and processing of these liquids. For this reason, degassing devices for removing gas admixtures may be arranged in processing plants that handle and process the aforementioned gas-laden liquid foods or other liquids. These processing plants may, for example, be pasteurization plants, UHT plants or evaporators. Degassing devices of the aforementioned type are, for example, described in EP 1 866 046 Bl or DE 297 22 673 UL Generally, degassing is forced in known degassing devices by exposing the liquid to a vacuum that is generated by a vacuum source, such as a liquid ring pump, connected to the head space of the degassing tank.

In other fields of the food and beverage industry as well such as transferring milk to milk collecting tankers, significant foam problems frequently occur in an air separator arranged in the measuring arrangement so that even foam collecting tanks must be provided on the one hand to prevent foam from exiting into the environment and on the other hand to return the liquid contained in the foam to the collector (DE 38 03 572 Al).

During degassing in the containers of the known degassing devices or also in containers in which foaming liquids may be treated and processed, the liquid generates foam on a free surface of a liquid supply or on a free surface of a liquid film by which the liquid may be introduced into the liquid supply, and the foam may grow toward a head space of the container starting from the free surfaces. The foaming may be so strong that the entire head space of the degassing container fills with foam and the foam therefore may bring the degassing process to a standstill, or at least may significantly inhibit it so that overall the process control is greatly impeded. If the foam enters a vacuum source that may exist, the degassing process must then be stopped. Accordingly, there may be a need to control the foaming in the containers for treating and processing liquids themselves where the foaming originally takes place. If undesired foam must be held in a foam collecting tank, there may also exist a need of controlling the foaming here or at the site of its origin, or respectively to then destabilize the foam and convert it into liquid.

It is known to fight foam chemically, mechanically and thermally. Fighting by adding chemical agents is generally not done with liquid food products in order to avoid contamination. Mechanical foam destroyers may yield unsatisfactory results at high foaming rates due to excessively low performance and a relatively extensive and sometimes also complicated design effort which must be pursued with regard to production, or respectively adaptation to the wide range of application requirements.

The destruction of undesired foam bubbles may be founded on the insight that the foam bubble decomposes when its volume is no longer stable. The volume of a foam bubble may be determined by the equilibrium between the pressure of the captured gas on the one hand and the sum of two pressures on the other hand, i.e., the pressure at which the treatment process for the liquid takes place, and the pressure that arises from the surface tension of the foam bubble.

The aim of foam destruction in a thermal manner, i.e., either by heating or cooling, therefore may be to significantly disrupt the aforementioned state of equilibrium. Heating the foam bubbles may cause an increase, and cooling may lead to a decrease, in the respective inner pressure of the foam bubbles. For this purpose, DE 21 63 666 Al discloses that it is useful to disrupt the state of equilibrium between the surface tension and inner pressure of all or a part of the foam bubbles to be destroyed by changing the inner pressure of the foam bubbles. In this regard, it is proposed to increase the inner pressure by heating up all or a part of the foam bubbles, for example by heating up the foam bubbles electrically by installing an electrically conductive resistance wire in the foam zone.

Another suggestion provides heating up the foam bubbles by blowing in hot heating gases into the foam zone. With the first suggestion, operational reliability and temperature maintenance may be problematic, and with the second suggestion, the required product and quality assurance no longer exist due to potential contaminants. Another suggestion that satisfies sanitary and hygienic requirements, at least when its solvent is suitably configured, that applies to liquid food products to be treated in the context of the disclosure, provides heating the foam bubbles with a heat exchanger loaded with warmer gaseous or liquid media and mounted in the foam zone.

The disclosure in DE 37 27 132 Al lags behind the last-cited suggestion since it proposes strongly reducing the mechanical strength of the foam in a manner known per se by introducing thermal energy in a method for destabilizing and destroying foams; however, the relevant introduction consists of a problematic supply of steam or heated gas within the context of the problem addressed here. Moreover, the problematic supply of these substances is combined with means for mechanical foam destruction or with means for generating ultrasound that require additional design effort and expense.

DE 43 04 808 Al describes a method and a device for filling containers with milk. Bottles are used as the containers, wherein the objective is achieved of eliminating during the filling process the foam arising while adding milk to the containers and simultaneously ensuring an exact filling quantity in the container. The solution to this objective consists inter alia of overfilling the bottle with milk in the vacuum area and then drawing off the overfilled milk with all of the formed foam the given filling level using a vacuum to and collecting it in a separate receptacle. The relevant person skilled in the art gathers from the document the information that is impossible or at least problematic to destroy the foam (in particular milk foam) by heating apparatuses that extend into the foam. Instead, it is proposed to draw off the forming foam and collect it in a separate receptacle.

DE 1 017 140 Al discloses a device for destroying foam in liquid evaporators in which the liquid is evaporated in particular also in a vacuum. The vacuum in this case serves to lower the evaporation temperature and not, for example, to draw off the foam. To strengthen the vacuum-resistant evaporator jacket, it is known to provide a reinforcing ring. The subject matter of the application exploits the known insight that foam bubbles collapse on cooled walls, and achieves the objective task by configuring the steam separator jacket with a cleaning-friendly reinforcement and simultaneously using this reinforcement to destroy foam. This objective is solved by providing a welded-in ring approximately in the middle of the stepped evaporator jacket that serves to reinforce the jacket and channel a coolant. The relevant person skilled in the art gathers from the document the information that it is known to disrupt the equilibrium of the foam bubbles by cooling and thereby bring about the destruction of the foam. Moreover, this prior art discloses stepping down the diameter of the container jacket in the region of the foaming from outside to inside, wherein the stepping is formed by a tubular ring. The cooling zone formed by the tubular ring therefore only acts tangentially from the outside on the foam growing over the entire evaporator cross-section.

DE 10 2004 062 804 B3 describes a device for controlling the temperature of objects and/or media. This temperature control, heating or cooling, is carried out using at least one so-called thermal element block. This thermal element block is a flat structure that consists of a plurality of Peltier elements which are alternately switched electrically in sequence and thermally in parallel and are covered on the outside with an electrically insulating and thermally conductive layer. The medium to be heated or cooled is accommodated in at least one funnel-shaped recess that has an inflow opening at its lowest point and has a peripheral outflow channel at the top edge that is loaded via an overflow edge. The medium flows through the recess from the inflow opening to the outflow channel. The outflow channel is enclosed on the outside by a seal that locks and seals the interior of the recess with the thermal element block. Between the medium flowing through the recess and the flat thermal element block that more or less functions as a recess cover, a direct heat exchange takes place (heating or cooling). This prior art does not disclose any use that references a destruction of foam forming from the liquid or suggests a relevant use. Moreover, the flat thermal element block that heats or cools the respective medium may not have an external flow around it or an internal flow through it.

The present disclosure may present, in some embodiments, a method and a device for controlling foaming in a container for liquids or for foams that effectively controls and limits foaming and prevents the growth of the foam beyond a tolerable amount while ensuring the sanitary and hygienic process control requirements.

It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.

SUMMARY OF THE DISCLOSURE

In a first aspect of the disclosure is disclosed a method for controlling foaming in a liquid container, • wherein a liquid is fed to the liquid container, is treated therein and dwells, and is discharged from the liquid container as a treated liquid below a free surface formed by the liquid in the liquid container, • wherein a foam forming from the liquid at a liquid temperature is released above the free surface and grows, • wherein starting at a heating distance from the free surface, the growing foam initially experiences heating from the liquid temperature to a heating temperature in a register system consisting of a heating and a cooling register, • wherein starting at a cooling distance from the heating distance, the further growing heated foam then experiences cooling to a cooling temperature in the register system, • wherein means for performing the heat exchange to heat and cool the foam are permeable to flow in the direction of growth of the foam, • wherein the heating and/or the cooling temperature is/are adjusted depending on the properties of the liquid and/or of the treated liquid, and/or the physical parameters, and • wherein the properties of the liquid are understood to be the volumetric flow, viscosity, pressure, temperature and/or the composition of the liquid in the region of the infeed into, or in the region of the discharging from, the liquid container, and the physical parameters are understood to be the pressure and/or the result of foam destruction in the liquid container.

In a further aspect of the disclosure is disclosed a method for controlling foaming in a foam container, • wherein the foam is fed to the foam container at a temperature that exists in the region of the infeed into the foam container, grows there, and is discharged from the foam container as a liquid arising from the foam, • wherein starting at a specified target foam height relative to the foam container, the growing foam first experiences heating from the temperature that exists in the region of the infeed into the foam container to a heating temperature in a register system consisting of a heating and a cooling register, • wherein starting at a cooling distance from the target foam height, the further growing heated foam then experiences cooling to a cooling temperature in the register system, • wherein means for performing the heat exchange to heat and cool the foam are permeable to flow in the direction of growth of the foam, • wherein the heating and/or the cooling temperature is/are adjusted depending on the properties of the foam and/or the physical parameters, and • wherein the properties of the foam are understood to be the volumetric flow, viscosity, pressure, temperature and/or the composition of the foam in the region of the infeed into the foam container, and the physical parameters are understood to be the pressure and/or the results of foam destruction in the liquid container.

The method according to the disclosure is based on a liquid container that is fed liquid which is treated therein and dwells and is discharged from the liquid container as a treated liquid below a free surface formed by the liquid in the liquid container. The general mode of operation of the method may treat a foam that is generated on the free surface of the liquid and from it at a liquid temperature, and that grows in the space above proceeding from this free surface. The foam may possess the temperature of the liquid, or possibly may have a slightly lower temperature. This free surface may be a free surface of the liquid supply in the liquid container, a level of this liquid supply generally with a controlled height, and/or the free surface of a liquid film through which the liquid is introduced into the liquid supply. The term “grow” or respectively a “direction of growth” is understood in the following to be the direction of movement of the foam that takes place, wherein this may also run differently than the direction of gravity.

This growth of foam may therefore be a dynamic process of foam propagation. In some embodiments, the inventive basic concept may start at the boundary surface of foam propagation. Starting at a heating distance from the free surface, the foam that grows with the liquid temperature may initially experience a heating from the liquid temperature to a heating temperature in a register system consisting of a heating and a cooling register. This heating distance may first need to be overcome by the growing foam before heating starts. Depending on the liquid, the heating distance may be fixed or adjustable as well in the degassing container. The region in which the heating takes place may be limited and specified measured in the direction of growth. The foam bubbles may necessarily expand with the local heating, which may be basically limited to this region by thermodynamic laws; the above-addressed state of equilibrium may be disrupted and the foam bubbles may become unstable. The boundary surface of foam propagation may be forced to advance by the heating.

Starting at a cooling distance from the heating distance, the further growing heated foam then may experience a cooling to a cooling temperature in the register system which may fall below the liquid temperature. The cooling distance may also relate to the foamgenerating surface, wherein the cooling distance is then greater than the heating distance. The region in which the cooling takes place may also be limited and specified measured in the direction of growth. Due to the sudden cooling of the liquid lamellae encasing the foam bubbles, the state of equilibrium of the foam bubbles may be further disrupted, opposite that of the heating. The foam bubbles may become more instable and burst due to the changing viscosity of the liquid lamellae, and the foam may therefore collapse on itself in this region and decrease to an associated liquid volume that drains in the direction of gravity. Viewed in the direction of growth, the foam propagation may have concluded at the end of the cooling or respectively the cooling zone, or at a reasonable distance from this end.

The means for performing the heat exchange to heat and cool the foam, i.e., the register system consisting of a heating and a cooling register, may be formed to channel a flow in the direction of growth of the foam.

In some embodiments, the heating and/or cooling temperature may be adjusted depending on the properties of the liquid and/or the physical parameters. The properties of the liquid may be understood to be the volumetric flow, viscosity, pressure, temperature and/or the composition of the liquid in the region of the infeed into, or the region of the discharging from, the liquid container, and the physical parameters may be understood to be the pressure and/or the result of foam destruction in the liquid container. The result of foam destruction may be indicated by whether foam exists and possibly still grows above the cooling of the foam. A signal generated by this foam may then be used to adjust the heating and/or cooling temperature.

The method according to the disclosure for controlling foaming in a foam container may, in some embodiments, be based on this foam container to which foam may be fed at a temperature that exists in the region of the infeed into the foam container and grows there, and may be discharged from the foam container as a liquid arising from the foam. The inventive basic concept may again start at the boundary surface of foam propagation. Starting at a specified target foam height relative to the foam container, the growing foam first may experience heating from the temperature that exists in the region of the infeed into the foam container to a heating temperature in a register system consisting of a heating and a cooling register. Starting at a cooling distance from the target foam height, the further growing heated foam then may experience cooling to a cooling temperature in the register system.

The heating and/or the cooling temperature may be adjusted depending on the properties of the foam and/or the physical parameters, wherein the properties of the foam may be understood to be the volumetric flow, viscosity, pressure, temperature and/or the composition of the foam in the region of the infeed into the foam container, and the physical parameters may be understood to be the pressure in the foam container.

In some embodiments, the respective method according to the disclosure may be designed in principle so that the differently temperature-controlled foam regions either slightly extend into each other, or respectively overlap due to their heating and cooling, or may be adjacent to each other without extending into each other or overlapping in this regard. As provided in a suggestion, it has proven to be advantageous in some embodiments when an extension region of the heating and heated foam and an extension region of the cooling and cooled foam, viewed in an associated direction of growth of the foam, may be directly adjacent without completely or at least partially overlapping each other. In this embodiment of the method, the foam may first heat and expand unhindered across its overall generation front, or respectively supply surface from which it grows, in order to then subsequently experience unhindered cooling and destruction under the same geometric conditions.

The hygienic and sanitary requirements to which the treatment and processing of liquid foods must be subjected may be adequately satisfied within the context of the respective method according to the disclosure in that the foam may be heated and cooled by an indirect heat exchange, for example at walls of heat exchangers that may be largely permeable to the foam in the direction of growth of the foam. A heating medium, preferably hot water, and a coolant, preferably cold water, may be provided as the heat transfer medium for the indirect heat exchange. However, hot steam or hot gas may also be used. The heating medium usefully may have a heating medium temperature preferably up to 90°C depending on the liquid temperature of the liquid or the temperature that exists in the area of the infeed into the foam container. The coolant usefully may have a coolant temperature preferably down to 12 to 14°C for milk and down to 6°C for fruit juices also depending on the respective liquid or foam temperature, whereby a cooling of the foam to a temperature level below the liquid or foam temperature may also be feasible.

The disclosure furthermore proposes, in some embodiments, that the foam may be heated and/or cooled by a direct heat exchange based on the Peltier effect. In this case, the heating and cooling register may be designed very cleaning-friendly in terms of CIP cleaning when the Peltier elements are suitably designed.

In some embodiments, it may be particularly useful when a cooling output in the region of foam cooling is designed to be greater than a heating output in the region of foam heating. Beyond the relative dimensions between a required heating and cooling surface given by the geometric design conditions, the relation between the heating and cooling output may be changed by the effective driving temperature difference in the respective heat exchangers of the heating and cooling zone. In this context, the heating medium and coolant temperature may be available as influential variables that may be changed within limits.

The heating and/or the cooling temperature may be adjusted as provided in another suggestion by means of an adjusting function created and saved before or while starting up the liquid or foam container. The optimum conditional relationships between the properties of the liquid to be treated and processed and/or the physical parameters on the one hand, and the heating and the cooling temperature on the other hand may be saved in this adjusting function so that a fully automated method may be performed to control foaming in the liquid container for liquids and in the foam container for foams.

The liquid container for liquids with a device for controlling foaming in the liquid container suitable for performing the associated method according to the disclosure may consist in a manner known per se of a liquid container that has an entry for the liquid and an outlet for a treated liquid. In the liquid container, the liquid may form a free surface with a level that may be preferably controlled by a level control apparatus.

In some embodiments, the device for controlling foaming in the liquid container may be distinguished according to the disclosure in that a register system consisting of a heating and a cooling register is provided at a heating distance from the free surface in the foaming region with the heating register. The cooling register may be arranged offset by a cooling distance from the heating register viewed in the direction of growth of the foam. The register system may be associated with a control apparatus that changes a heating output of the heating register and/or a cooling output of the cooling register depending on the properties of the liquid and/or the physical parameters. The control apparatus may be connected to a measuring apparatus that establishes at least one of the properties of the liquid or of the treated liquid and/or the physical parameters. The measuring apparatus may be configured in light of the physical parameters such that it may be a measuring apparatus for detecting foam (such as a foam sensor), wherein this foam grows above the cooling register and generates a foam signal there that is transmitted to the control apparatus.

In some embodiments, the foam container for foams with a device for controlling foaming in the foam container suitable for performing the associated method may consist in a manner known per se of a foam container that has an entry for the foam and an outlet for a liquid arising from the foam. The foam may be ultimately fed to the foam container for the purpose of a desired decomposition and grows there.

In some embodiments, the device for controlling foaming in the foam container may be distinguished according to the disclosure in that a register system consisting of a heating and a cooling register is provided and positioned with the heating register at a height in the foam container determined by a target foam height. The cooling register may be arranged offset by a cooling distance from the heating register viewed in the direction of growth of the foam. The register system may be associated with a control apparatus that changes a heating output of the heating register and/or a cooling output of the cooling register depending on the properties of the foam and/or the physical parameters. The control apparatus may be connected to a measuring apparatus that establishes at least one of the properties of the foam and/or the physical parameters. The measuring apparatus may be configured in light of the physical parameters such that it is a measuring apparatus for detecting foam (such as a foam sensor), wherein this foam grows above the cooling register and generates a foam signal there that is transmitted to the control apparatus.

A heat exchanger is understood as the heating and the cooling register respectively for the indirect heat exchange which has a plurality of hollow structures that may be each bordered by flat or curved walls. When joined together, the hollow structures may be permeable to flow to the outside in the direction of growth of the foam. The flat walls form flow-through chambers that may have different geometries such as rectangular, square or triangular. The curved walls border e.g. oval, elliptical or circular flow cross-sections. On the inside, a thermal transfer medium flows through the hollow structures, a heating medium in the heating register and a coolant in the cooling register.

The heating and/or the cooling register for the direct heat exchange may be designed in each case as a Peltier element according to one suggestion.

Preferably, in some embodiments, for indirectly exchanging heat using a heat transfer medium, the disclosure moreover proposes a register system that may consist of a heating and a cooling register for the device for controlling foaming in the liquid and foam container, wherein the liquid and foam container that is suitable for performing the associated method according to the disclosure has been described above.

It has proven to be particularly useful, in some embodiments, with regard to effective foam destruction when an overall cooling surface of the cooling register is designed to be greater than an overall heating surface of the heating register. The overall cooling and overall heating surface may be each understood to be the sum of all heating or cooling heat exchanger surfaces of the cooling and heating register that act on the foam.

An embodiment with a simple design that may ensure the hygienic and sanitary requirements in treating and processing in particular liquid food products results according to a suggestion when the heating register consists of first pipes and the cooling register consists of second pipes. The first pipes and the second pipes may be arranged individually in a row next to each other and spaced apart from each other. The first pipes may be positioned at the heating distance from the foam-generating free surface in the liquid container, and may be positioned in the foam container at the height determined by the target foam height. The second pipes may be positioned in the liquid container at the cooling distance from the heating distance, i.e., proceeding from the heating distance, and may be positioned in the foam container at the cooling distance from the height determined by the target foam height, i.e., proceeding from the target foam height. Transverse to the respective direction of growth, the first and second pipes may be also arranged offset from each other, i.e., easily in that the second pipes may be positioned above, and distributed to the respective gaps between, the first pipes.

To prevent the cooling register realized with pipes from not engaging with the heating register, or respectively overlapping the heating register entirely or in sections, it may be suggested that the cooling distance always be greater than a greatest first diameter of the first pipes in the cooling distance. A simplification of the respective construction may result when the first pipes and the second pipes each have the same diameter, and the desired relation between the cooling and heating surface may be configured more easily and flexibly under the above diameter conditions when the first pipe has a greater diameter than the second pipe.

It is moreover suggested, in some embodiments, to design the first pipes and/or the second pipes as a monopipe. With this design, flow problems may be avoided in the distribution of the heating medium and coolant. It is moreover provided, in some embodiments, to design both the first pipe and the second pipe as a helically wound monopipe. This design moreover may make it possible to very easily arrange the monopipes wound in this manner with reference to the direction of growth of the foam and transverse thereto so that the monopipes, viewed in the direction of growth, may be each permeable to flow on the one hand, and on the other hand, they realize the required series connection of the heating and cooling register. This may be usefully accomplished in that the monopipes of the cooling zone may be on the one hand arranged axially offset relative to the monopipes in the heating zone and, on the other hand, may be positioned in a radial direction above the respective gaps between the monopipes in the heating zone. An possibly advantageous embodiment in this regard may provide that two second pipes may be each positioned symmetrically and evenly distributed above the respective gap between two adjacent first pipes.

Two solutions may be suggested for a simple and easily variable calibration and fastening of the registry system in any embodiment, or in the embodiment with first and second pipes. Both solutions may equally provide supporting the heating and cooling register on the liquid or foam tank via a plurality of supports that may be arranged evenly distributed over the circumference of the respective container and extend star-shaped toward the center of the respective container. The first solution may be distinguished in that the progression of each support with reference to the heating register results from a bottom contour of the heating register against which each support fits from below. In the second solution, the progression of each support with reference to the heating register may result from the positioning of the first pipe against which each support fits tangentially from below. In both solutions, preferably four supports may be provided.

In the embodiment of the register system with first and second pipes, the required positioning and fastening of the pipes according to the disclosure both in the direction of growth of the foam as well as transverse thereto may be very easily realized in that an imaginary line of contact is used as a reference line for positioning and fastening that may result from the contact points between the first pipes and the support tangentially adjacent thereto. Over the progression of the contact line, retaining means may be provided for the first and the second pipes on the support that may be securely connected to the support. The retaining means may be preferably designed as metal plates and may be oriented upright on the one hand in the direction of a longitudinal axis of the liquid or foam container and on the other hand in the direction of the contact line, which may inhibit the growth of the foam as little as possible. Two adjacent retaining means thereby may each immovably hold one first pipe and at least one second pipe in the direction of the contact line.

BRIEF DESCRIPTION OF THE DRAWINGS

A detailed representation of the disclosure results from the following description and the accompanying figures of the drawing and from the claims. Whereas the disclosure is realized in a wide variety of embodiments, a preferred embodiment of a liquid container and of a foam container according to the disclosure is portrayed and described in the drawing, wherein the foam container according to the disclosure is provided individually or in combination with a liquid container according to the prior art. Moreover, a preferred exemplary embodiment of a register system is portrayed that consists of a heating and a cooling register for the device according to the disclosure for controlling foaming in the liquid or foam container, that is suitable for performing the associated method according to the disclosure, and will be described below in terms of design and function. In the figures:

Fig· 1 shows a schematic representation of a liquid container with different options for arranging an entry for the liquid to be treated and an outlet for the treated liquid according to the prior art, together with a register system according to the disclosure consisting of a heating and a cooling register;

Fig. 2 shows a schematic representation of a foam container according to the prior art together with a register system according to the disclosure according to Fig. 1;

Fig. 3 shows a schematic representation of a liquid container according to the prior art in a known combination with a foam container according to the disclosure according to Fig. 2;

Fig. 4 shows a meridian section in a specific design of the essential parts of a liquid container with a register system according to the disclosure according to Fig. 1 corresponding to a section identified with A-A in Fig. 6;

Fig. 5 shows a perspective representation of the liquid or foam container according to Fig. 4, or respectively Fig. 2 in a specific embodiment, wherein the device according to the disclosure is exposed by omitting a jacket and a top floor of the respective container, and a schematic representation of a control apparatus with associated means for admitting a heating medium and coolant to a register system consisting of a heating and cooling register, wherein the central area of the register system is not portrayed;

Fig. 6 shows a plan view of the liquid or foam container according to Fig. 4 and 5, wherein the central region of the register system is not portrayed;

Fig. 7 portrays an enlarged representation of a first section identified in Fig. 4 with “B” in the region of the device according to the disclosure;

Fig. 8 shows a further enlarged representation of a second section from the first section according to Fig. 7 that is identified in Fig. 7 with “C”; and

Fig. 9 shows a front view and a plan view of retaining means portrayed in Fig. 7 and 8 for pipes of the register system according to the disclosure in an enlarged representation.

DETAILED DESCRIPTION

The disclosure is based on a liquid container 100 for liquids P according to the prior art (Fig. 1 and 4), for example a degassing device in which the liquid P such as a liquid food product is degassed. The liquid container 100 consists of a container 2 in the form of a substantially cylindrical container jacket 2c with a bottom floor 2b and a top floor 2a. The bottom floor 2b has either a central drain port 2d as portrayed in Fig. 4 with an outlet for the treated liquid A(P’) for a degassed, or respectively treated liquid P’, or a tangentially arranged drain port (schematically indicated in Fig. 1; not portrayed in Fig. 4). The liquid P is fed via an entry for the liquid E(P) into the liquid tank 100 where it forms a liquid supply. In this regard, the following options are known:

• an entry for the liquid E(P) through the bottom floor 2b centrally from below that then generally runs concentrically through the drain port 2d, or laterally from below, • an entry for the liquid E(P) through the container jacket 2c, either above or below a free surface N or a free level of the liquid supply, or • an entry for the liquid E(P) from above.

The entry for the liquid E(P) from below or above is generally continued by a feed pipe (not portrayed), the end of which terminates in a peripheral annular gap of an inlet valve (also not portrayed) or between a distribution shield 3 and a baffle plate (not portrayed). Through the peripheral annular gap, the liquid P is either expelled as a free jet (inlet valve) or on the distribution shield 3 as a liquid film F into the liquid container 100. The free surface N of the largely degassed, or respectively to be degassed liquid P’, P that forms the liquid supply in the liquid container 2 is adjusted with a level control apparatus (not portrayed). The partially degassed or largely degassed liquid film F enters the free surface N at the bottom end of the distribution shield 3. The liquid fractions layered on and entering the free surface N via the distribution shield 3 in the form of the liquid film F dwell in the liquid container 2 with an average dwell time and can further degas there via the free surface N with the assistance of the gas bubble buoyancy.

A foam S that forms during the treatment, or respectively the degassing of the liquid P is released above and from the free surface N and grows in the direction of an interior formed by the container jacket 2c and in the direction of a headspace formed by the top floor 2a. A respective direction of growth of the foam is designated with r(S).

The disclosure is moreover based on a foam container 200 for foam S according to the prior art (Fig· 2 and 3), for example a foam collection tank in which intrinsically undesirable foam S is accommodated and where it remains until its desired decomposition into liquid P. Like the liquid container 100, the foam container 200 consists of a container 2 in the form of a substantially cylindrical container jacket 2c with a bottom floor 2b and a top floor 2a. The foam container 200 has an entry for the foam E(S) for the foam S and an outlet of the liquid A(P) for the liquid (P) arising from the form S.

A combination of the above-outlined liquid container 100 according to Fig. 1 and the foam container 200 according to Fig. 2 is portrayed in Fig. 3. The foam S arising in the liquid container 100 is discharged from the headspace of the container 2 and fed to the foam container 200 at a temperature that exists at the region of the infeed into the foam container 200. The liquid P arising in the foam container 200 from the foam S is fed to the liquid supply in the liquid container 100 below the free surface N.

A register system 20 according to the disclosure consisting of a heating register 20.1 and a cooling register 20.2 is schematically portrayed in Fig. 1 to 3 and in Fig. 4 to 9 in a specific design and will be described below with reference to Fig. 4 to 9.

The register system 20 is arranged in the liquid container 100 (Fig. 1, 4 to 8) so that the heating register 20.1 is spaced apart from the free surface N at a heating distance h. The cooling register 20.2 is arranged offset by a cooling distance k from the heating register 20.1 viewed in the direction of growth of the foam r(S) (see also Fig. 1). A control apparatus 13 that changes a heating output HL of the heating register 20.1 and/or a cooling output KL of the cooling register 20.2 depending on the properties of the liquid P or of the treated liquid P’ and/or the physical parameters is associated with the register system 20 (Fig. 5). The control apparatus 13 is connected to a measuring apparatus 14 that establishes at least one of the properties of the liquid P, P’ and/or the physical parameters.

The register system 20 consisting of a heating 20.1 and a cooling register 20.2 is arranged in the foam container 200 so that its heating register 20.1 is positioned at a height in the foam container 200 determined by a target foam height N* (Fig. 2, 3, and 5 to 8). The cooling register 20.2 is arranged offset by a cooling distance k from the heating register 20.1 viewed in a direction of growth of the foam r(S). A control apparatus 13 that changes a heating output HL of the heating register 20.1 and/or a cooling output KL of the cooling register 20.2 depending on the properties of the foam S and/or the physical parameters is associated with the register system 20. The control apparatus 13 is connected to a measuring apparatus 14 that establishes at least one of the properties of the foam S and/or the physical parameters. Moreover, a measuring apparatus 14 can be arranged in the headspace of the liquid or foam container 100, 200 above the cooling register 20.2 and is a measuring apparatus for detecting foam (such as a foam sensor), wherein this foam grows above the cooling register 20.2 where it generates a foam signal LS that is transmitted to the control apparatus 13 (Fig. 5).

The register systems 20 for the liquid or foam container 100, 200 are usefully designed substantially the same. Within the context of the indirect heat exchange, a heating medium Wh that has a heating medium temperature Th flows through the heating register 20.1, and a coolant Wk that has a coolant temperature Tk flows through the cooling register 20.2 (Fig. 5 and 6). An overall cooling surface Ok of the cooling register 20.2 is preferably designed to be greater than an overall heating surface Oh of the heating register 20.1. In the present exemplary embodiment, the heating output HL is changed by the volumetric flow of the heating medium Wh and/or the cooling output KL is changed by the volumetric flow of the coolant Wk depending on the properties of the liquids P, P’, or respectively of the foams S, and/or the physical parameters (Fig. 5). The flow of the heating medium Wh is controlled by the heating register 20.1 via a first valve 15 that is connected by a signal to the control apparatus 13, and the flow of the coolant Wk is controlled by the cooling register 20.2 via a second valve 16.

According to an advantageous and preferred embodiment, the heating register 20.1 consists of first pipes 8, and the cooling register 20.2 consists of second pipes 9 (Fig. 4 to 8). The first pipes 8 and the second pipes 9 are arranged individually in a row next to each other and spaced apart from each other. The first pipes 8 are positioned at the heating distance h from the free surface N (with reference to the liquid container 100) or at the height determined by the target foam height N* (with reference to the foam container 200). The necessary offset of the first and the second pipes 8, 9 to each other and in the direction of grown r(S) of the foam S is ensured by positioning the second pipes 9 at the cooling distance k from the heating distance h, or at the cooling distance k from the height determined by the target foam height N*. Complete coverage of the foam-generating surface in the liquid container 100, or respectively the overall supply surface in the foam container 200, is ensured by arranging the second pipes 9 above, and distributed to the respective gaps between, the first pipes 8.

If, as preferably provided, the cooling distance k is always greater than a greatest first diameter Dh of the first pipes 8 at the cooling distance k, a complete or at least partial engagement, or respectively a relevant overlapping of the heating and cooling register 20.1, 20.2 is prevented.

The first pipes 8 and the second pipes 9 are each preferably designed with the same diameter amongst themselves, and the first pipe 8 preferably has a greater diameter, the first diameter Dh, than the second pipe 9 with a second diameter Dk.

The construction of the piping in the register system 20 is significantly simplified if the first pipes 8 and/or the second pipes 9 are each designed as a monopipe. Another simplification of the construction results when the first pipe 8 and the second pipe 9, each designed as a monopipe, are designed helically wound. Easy and gap-free coverage of the foamgenerating surface of the liquid P, or respectively of the foam surface of the foam S, is preferably achieved by positioning two second pipes 9 above the respective gap between two adjacent first pipes 8 symmetrically and evenly distributed (Fig. 7 and 8).

In consideration of a useful and expedient configuration of the register system 20 in the tubular embodiment, and preferably in the respective design as a monopipe heat exchanger, in particular in consideration of the ratio between the heating and cooling surface Oh, Ok, the specific relevant design provides, for example, configuring the cooling surface Ok via the second pipe 9 so that it has the second diameter Dk = 8 mm and an overall length, a second length Lk. The heating surface Oh in the context of the aforementioned cooling surface Ok is configured via the first pipe 8 so that it has the first diameter Dh = 10 mm and an overall length, a first length Lh = Lk/2. With regard to the above required ratio of the cooling output Kl to the heating output Hl, a ratio of the cooling surface Ok to the heating surface Oh accordingly results in the exemplary embodiment:

Ok/Oh = dKL_K/dHL_H = 8 L_k/10 L_H = 8 L_k/(10 L_k/2) = 2 x 8/10 = 1.6, which adequately fulfills the condition that the cooling surface Ok is to be configured to be greater than the heating surface Oh.

In the embodiment of the register system 20, it is important for the foaming to be unrestricted, or only marginally restricted in the growing direction of the foam r(S) by the first and second pipes 8, 9. For this purpose, the first and second pipes 8, 9 are sufficiently spaced apart from each other on the one hand, and on the other hand, are numerous enough to ensure a comprehensive and sufficient thermal treatment of the foam S.

A heating and/or a cooling temperature ΤΙ, T2 of the foam S (Fig. 7 and 8) is/are adjusted by the control apparatus 13 (Fig. 5), depending on the properties of the liquid P and of the foam S and the physical parameters, with the assistance of the heating medium Wh at heating medium temperature Th and the coolant Wk at the coolant temperature Tk, so that it is possible to thereby control foaming.

In the liquid container 100, the foam S grows from the free surface N approximately at a liquid temperature T3 and is initially located in the region of the heating distance h. A foam Sh heated at the heating surface Oh to the heating temperature T1 is located in the region of the cooling distance k, and a cooling and cooled foam Sk, the latter at the cooling temperature T2 which decomposes into liquid while cooling, is located within the region above the cooling distance k (Fig. 7, 8 and 1, 4).

In the foam container 200, a foam S is stored at a temperature corresponding to that existing in the region of the infeed of the foam S into the foam container 200, and that correspondingly lies slightly below the liquid temperature T3. If the foam S grows up to the target foam height N* from where the heating register 20.1 has its beginning in the direction of growth of the foam r(S), it is heated at heating surface Oh up to the heating temperature Tl. It is then located in the region of the cooling distance k and experiences further treatment as already described above (Fig. 7, 8 and 2).

The register system 20 is preferably supported on the liquid or foam container 100, 200 via a plurality of supports 7 that are arranged preferably evenly distributed over the perimeter of the respective container 100, 200, and preferably extends in a star shape toward the center of the respective container 100, 200 (Fig. 5 to 8). Preferably four supports 7 are provided (Fig. 6, 5), wherein this number can also vary by one to two on both sides. In a generalized embodiment (not portrayed) of the register system 20, the progression of each support 7 with reference to the heating register 20.1 preferably results from a bottom contour of the heating register 20.1 against which each support 7 fits from below.

In the presently described specific embodiment of the register system 20 in the form of a monopipe, at least for the heating register 20.1, the progression of each support 7 as portrayed in Fig. 5 to 8 with reference to the heating register 20.1 results from the positioning of the first pipes 8 against which each support 7 fits tangentially from below. An imaginary contact line PL results on each support 7 from the contact points between the first pipes 8 and the support 7 tangentially lying against each of them. Over the progression of the contact line PL, retaining means 12 are provided for the first and the second pipes 8, 9 on the support 7 that are securely connected to the support 7. The retaining means 12 are preferably designed as metal plates and are oriented upright on the one hand in the direction of a longitudinal axis of the respective container 100, 200, and on the other hand in the direction of the contact line PL. Two adjacent retaining means 12 each immovably hold one first pipe 8 in the direction of the contact line PL, and each retaining means 12 also immovably holds at least one second pipe 9 in the direction of the contact line PL.

In the embodiment portrayed as an example, the register system 20 consists of the first and the second pipe 8, 9 that are each designed as a monopipe and are preferably helically wound. The first pipe 8 lies on the supports 7 and is held in position between two retaining means 12. It functions as a heating pipe and, measured from the free surface N, has the heating distance h (Fig. 7, 8). In the foam container 200, the heating register 20.2 is positioned at a height determined by the target foam height N*. The heating register 20.2 accordingly defines the entry of the foam S into a warming, or respectively heating zone in the direction of growth of the foam r(S). Two directly adjacent second pipes 9 are arranged in the region above the cooling distance k with reference to the intermediate distance between two adjacent first pipes 8. The second pipes 9 are supported in cutouts in the retaining means 12 such that both the distance between the pipes themselves as well as with reference to the first pipes 8 results, also in consideration of ensuring the cooling distance k.

Only the supports 7 and the holding means 12 that are designed as narrow as feasible with regard to strength lie in the direction of growth of the foam r(S), without significantly affecting its temperature. With reference to the direction of growth of the foam in the correspondingly projected direction, they tend to promote a mechanical impairment of the foam S and hence the desired foam destruction.

Moreover, the method according to the disclosure and the device for performing it yield another positive result This is that the highly effective foam destruction at the side of foam generation in the liquid container 100 or in the foam container 200 leads to a reforming into pure liquid. The aromas that are contained in the foam and may be highly volatile and hence easily leave the headspace of the containers 100, 200 under the forceful effect of a vacuum source that may be present are retained in the reformed liquid and are either directly returned via the free surface N or by the foam container 200 into the liquid supply over a short path.

In the claims which follow and in the preceding description of the disclosure, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense,

i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the disclosure.

REFERENCE SIGN LIST OF THE USED ABBREVIATIONS

100 Liquid container

200 Foam container

Container

2a Top floor

2b Bottom floor

2c Container jacket

2d Drain port

Distribution shield

Support

First pipe (heating pipe)

Second pipe (cooling pipe)

Retaining means

Control apparatus

Measuring apparatus

First valve

Second valve

Register system

20.1 Heating register

20.2 Cooling register

A(P) Outlet for liquid

A(P’) Outlet for the treated liquid

Dh First diameter (first pipe; heating pipe)

Dk Second diameter (second pipe; cooling pipe)

E(P) Entry for liquid

E(S) Entry for foam

F Liquid film

HL Heating output

KL Cooling output

Lh First length (first pipe; heating pipe)

Lk Second length (second pipe; cooling pipe)

LS Foam signal

N Free surface (free level)

N* Target foam height

Oh Heating surface (first pipe; heating pipe)

Ok Cooling surface (second pipe; cooling pipe)

P Liquid

P’ Treated liquid

PL Contact line

S Foam

Sh Heating and heated foam

Sh Cooling and cooled foam

T1 Heating temperature (of the foam S)

T2 Cooling temperature (of the foam S)

T3 Liquid temperature (of the liquid P, P’)

Th	Heating medium temperature
Τκ	Coolant temperature
Wh	Heating medium
5 Wk	Coolant
h	Heating distance (first pipe; heating pipe)
k	Cooling distance (second pipe; cooling pipe)
r(S)	Direction of growth of the foam

Claims

Claims

1. A method for controlling foaming in a liquid container, • wherein a liquid is fed to the liquid container, is treated therein and dwells, and is discharged from the liquid container as a treated liquid below a free surface formed by the liquid in the liquid container, • wherein a foam forming from the liquid at a liquid temperature is released above the free surface and grows, • wherein starting at a heating distance from the free surface, the growing foam initially experiences heating from the liquid temperature to a heating temperature in a register system consisting of a heating and a cooling register, • wherein starting at a cooling distance from the heating distance, the further growing heated foam then experiences cooling to a cooling temperature in the register system, • wherein means for performing the heat exchange to heat and cool the foam are permeable to flow in the direction of growth of the foam, • wherein the heating and/or the cooling temperature is/are adjusted depending on the properties of the liquid and/or of the treated liquid, and/or the physical parameters, and • wherein the properties of the liquid are understood to be the volumetric flow, viscosity, pressure, temperature and/or the composition of the liquid in the region of the infeed into, or in the region of the discharging from, the liquid container, and the physical parameters are understood to be the pressure and/or the result of foam destruction in the liquid container.
2. A method for controlling foaming in a foam container, • wherein the foam is fed to the foam container at a temperature that exists in the region of the infeed into the foam container, grows there, and is discharged from the foam container as a liquid arising from the foam, • wherein starting at a specified target foam height relative to the foam container, the growing foam first experiences heating from the temperature that exists in the region of the infeed into the foam container to a heating temperature in a register system consisting of a heating and a cooling register, • wherein starting at a cooling distance from the target foam height, the further growing heated foam then experiences cooling to a cooling temperature in the register system, • wherein means for performing the heat exchange to heat and cool the foam are permeable to flow in the direction of growth of the foam, • wherein the heating and/or the cooling temperature is/are adjusted depending on the properties of the foam and/or the physical parameters, and • wherein the properties of the foam are understood to be the volumetric flow, viscosity, pressure, temperature and/or the composition of the foam in the region of the infeed into the foam container, and the physical parameters are understood to be the pressure and/or the results of foam destruction in the liquid container.
3. The method according to claim 1 or 2, wherein an extension region of the heated foam and an extension region of the cooled foam viewed in an associated direction of growth of the foam are directly adjacent to each other without completely or at least partially overlapping each other.
4. The method according to one of the preceding claims, wherein the foam is heated and cooled by indirect heat exchange.
5.

The method according to one of claims 1 to 3, wherein the foam is heated and/or cooled by direct heat exchange based on the Peltier effect.
6. The method according to claim 4, wherein a heating medium and a coolant are provided as the heat transfer medium for the indirect heat exchange.
7. The method according to one of claims 1 to 6, wherein a cooling output in the region of the cooling of the foam is configured to be greater than a heating output in the region of the heating of the foam.
8. The method according to one of claims 1 to 7, wherein the heating and/or the cooling temperature is/are adjusted by means of an adjusting function created and saved before or while starting up the liquid container and the foam container.
9. A liquid container for liquids with a device for controlling foaming in the liquid container suitable for performing the method according to claim 1, with the liquid container that has an entry for the liquid, with an outlet for a treated liquid, and with a free surface formed by the liquid in the liquid container, wherein • a register system consisting of a heating and a cooling register is provided, and its heating register is spaced apart at a heating distance from the free surface, • the cooling register is arranged offset by a cooling distance from the heating register viewed in a direction of growth of the foam, • the register system is associated with a control apparatus that changes a heating output of the heating register and/or a cooling output of the cooling register depending on the properties of the liquid, and/or the physical parameters, and • the control apparatus is connected to a measuring apparatus that establishes at least one of the properties of the liquid and/or the physical parameters.
10. A foam container for foams with a device for controlling foaming in the foam container suitable for performing the method according to claim 2, with the foam container that has an entry for the foam and an outlet for a liquid arising from the foam, wherein • a register system consisting of a heating and a cooling register is provided, and its heating register is positioned at a height in the foam container determined by a target foam height, • the cooling register is arranged offset by a cooling distance from the heating register viewed in a direction of growth of the foam, • the register system is associated with a control apparatus that changes a heating output of the heating register and/or a cooling output of the cooling register depending on the properties of the foam and/or the physical parameters, and • the control apparatus is connected to a measuring apparatus that establishes at least one of the properties of the foam and/or the physical parameters.
11. The liquid container according to claim 9 or the foam container according to claim 10, wherein a heating medium flows through the heating register, and a coolant flows through the cooling register.
12. The liquid container according to claim 9 or the foam container according to claim 10, wherein the heating register and/or the cooling register is/are each designed as a Peltier element.
13. A register system for the device for controlling foaming in the liquid container that consists of a heating and a cooling register according to claim 9, 11 or 12.
14. The register system for the device for controlling foaming in the foam container that consists of a heating and a cooling register according to claim 10, 11 or 12.
15. The register system according to claim 13 or 14, wherein an overall cooling surface of the cooling register is configured to be greater than the overall heating surface of the heating register.
16. The register system according to claim 13, wherein • the heating register consists of first pipes, and the cooling register consists of second pipes, • the first pipes and the second pipes are arranged individually in a row next to each other and spaced apart from each other, • the first pipes are positioned at the heating distance from the free surface or at the height determined by the target foam height, • the second pipes are positioned at the cooling distance from the heating distance or at the cooling distance from the height determined by the target foam height, • and the second pipes are arranged above, and distributed to the respective gaps between, the first pipes.
17. The register system according to claim 16, wherein the cooling distance is always greater than a greatest first diameter of the first pipes at the cooling distance.
18. The register system according to claim 16 or 17, wherein the first pipes and the second pipes each have the same diameter amongst themselves, and the first pipe has a greater diameter than the second pipe.
19. The register system according to one of claims 16 to 18, wherein the first pipes and/or the second pipes are each designed as a monopipe.
20. The register system according to claim 19, wherein the first pipe and the second pipe, each designed as a monopipe, are designed helically wound.
21. The register system according to one of claims 16 to 20, wherein two second pipes are each positioned symmetrically and evenly distributed above the respective gap between two adjacent first pipes.
22. The register system according to one of claims 13 to 21, wherein the register system is supported on the liquid container or the foam container via a plurality of supports that are arranged evenly distributed over the perimeter of the respective container and extend in a star shape toward the center of the respective container, and the progression of each support with reference to the heating register preferably results from a bottom contour of the heating register against which each support fits from below.
23. The register system according to one of claims 16 to 21, wherein the register system is supported on the liquid container or the foam container via a plurality of supports that are arranged evenly distributed over the perimeter of the respective container and extend in a star shape toward the center of the respective container, and the progression of each support with reference to the heating register results from the positioning the first pipes against which each support fits tangentially from below.
24. The register system according to claim 22 or 23, wherein four supports are provided.
25. The register system according to claim 23 or 24, wherein • an imaginary contact line results from the contact points between the first pipes and the support tangentially lying against each of the supports, • over the progression of the contact line, retaining means are provided for the first and the second pipes on the support, • the retaining means are securely connected to the support, • the retaining means are designed as metal plates and are oriented upright on the one hand in the direction of the longitudinal axis of the container and on the other hand in the direction of the contact line, • two adjacent retaining means each immovably hold one first pipe in the direction of the contact line, and

2016350039 03 Dec 2019 each retaining means immovably holds a second pipe in the direction of the contact line.