DE202021103254U1 - Vent hood for an unpressurized tank - Google Patents

Abstract

Ventilation hood (1) for a tank (2) operated without pressure, comprising: a ventilation pipe (3) which can be connected to the tank; a side wall (4) peripherally surrounding the ventilation pipe and having at least one screen (5) for the escape of air and the prevention of entry of solids; and a cover (6) covering the front side of the ventilation pipe, with a baffle plate (7) with a peripheral drainage channel (8) for catching liquid (9) running off on the inside (7a) of the baffle plate being arranged inside the screen in such a way that the ventilation pipe on the one hand and the cover and the baffle plate on the other hand form an angled ventilation channel (10) between them for centrifugally driven separation of liquid from an air flow (11)/steam flow on the baffle plate and for subsequent ventilation through the sieve.

Description

The invention relates to a ventilation hood for an unpressurized tank and a tank equipped with it, as well as a beverage treatment system with such a tank.

In the food industry, in addition to closed pressure vessels, unpressurized (atmospheric) tanks, boilers or similar vessels are also used, i.e. those in which the ambient pressure essentially prevails inside during operation. Such tanks require ventilation and venting in the upper area of the tank in order to allow pressure equalization with the environment. This is also called boiler breathing.

In tanks in particular where food is stored, it is necessary to prevent insects from entering the tank via the ventilation/vent. So-called ventilation hoods, which are installed in the upper floor / on the roof of the pressureless tank and are equipped with a fly screen, are common for this purpose.

From the US 4,889,160A for example, a tamper evident two-way vent assembly on food tanks is known. The vent assembly includes inner and outer stainless steel inverted cup shell members that nest within each other and are concentrically mounted on a bracket over a tubular vent opening in the container or tank. The outer shell member has a lower peripheral edge that rests on the surface of the tank. The inner shell member has a lower peripheral edge spaced from the surface of the tank. The outer shell member is formed with a plurality of small openings to allow air to flow in and out therealong, with a multi-directional flow path formed between the shell members.

the FR 2 988 081 A1 also discloses a device for partially closing the vent of a milk tank. The main body of the device comprises a tube which is extended at its upper end by a shell. A screen is closed at the top by a disc and is mounted within the shell in extension of the tube and coaxially therewith. The bowl includes an annular partition extending from the bottom of the bowl at a distance from an outer surface of the screen and from the side wall of the bowl. A cap is secured over the opening in spaced relation to cover the opening and form a flow passage between the cap and the opening.

The main problem with the known ventilation hoods, however, is that during a hot cleaning of the tank when changing from cold to hot, for example from a cold water rinsing step to a hot lye cleaning step, cleaning liquid, which is sprayed into the tank via a spray head or jet cleaner, together with is torn outwards through the ventilation hood by an upward flow of air. The air flow is created by the abruptly expanding air in the tank due to the heating by the cleaning medium. This problem occurs mainly in larger tanks with more than 10 m ³ content.

Since the liquid entrained into the environment can be hot lye, for example, this creates a safety risk. For example, CIP liquid entrained to the outside can rain down from the roof of the tank into the immediate vicinity. As a makeshift, an attempt was made to drain at least part of the cleaning solution through a drain pipe attached to the outside of the tank. However, this has often turned out to be insufficient.

There is therefore a need for ventilation hoods which are improved in comparison thereto.

The task is solved with a ventilation hood according to claim 1.

Accordingly, this is suitable for an unpressurized tank, boiler or similar container. The tank is used to hold food and/or its components, such as beverages or beverage components, in a food production plant, in particular in a bottling plant, and/or to hold auxiliary media such as cleaning media. An unpressurized tank/container is understood to be one in which the ambient pressure essentially prevails inside during operation.

The vent hood includes: a vent tube connectable to the tank; a sidewall peripherally surrounding the vent tube having at least one screen for exiting air and preventing ingress of solids such as insects; a cover covering the front side of the ventilation pipe; and a baffle having a peripheral gutter for collecting liquid runoff on the inside of the baffle. The baffle plate is arranged within the screen in such a way that the ventilation tube on the one hand and the cover and the baffle plate on the other hand have an angled and preferably essentially annular ventilation channel between them for the centrifugally driven separation of liquid from an air flow/vapor flow formation on the baffle plate and for subsequent venting through the screen.

The ventilation hood arranged on the roof/upper floor of the tank enables the tank to breathe in relation to the surrounding atmosphere and prevents insects or other solid bodies from entering the tank by means of the sieve or similar grid.

Amounts of air that suddenly expand in the tank from cold to hot in the course of hot cleaning of the tank when the medium is changed can thus escape through the ventilation hood. Droplets of the respective cleaning liquid that are entrained in the suddenly developing air flow are then separated on the baffle plate. Here, the liquid phase (droplets) of the air flow / vapor flow is separated from the gas phase (air) by a change of direction at the angled course of the ventilation duct, driven by centrifugal force, so that the separated liquid phase can drain off the baffle plate and collect in the drainage channel formed on it. From there, the collected liquid can be returned to the inside of the tank.

This prevents the liquid phase (droplets) from being entrained to a significant extent through the sieve into the surroundings of the tank and having to be discharged from there through drain pipes. Such devices on the outside of the tank are therefore not necessary.

In addition, a safety risk arising from the escape of cleaning liquid into the area surrounding the tank can be minimized. In addition, the collected cleaning liquid can be fed back into the tank or into the cleaning circuit, so that recycling and/or targeted disposal is possible in an equally environmentally friendly and economical manner.

Preferably, the vent hood further comprises drain pipes connected to the downcomer and traversing down the vent channel for returning collected liquid from the downcomer to the vent pipe. On the one hand, this allows the air flow to rise unhindered through the ventilation pipe and to flow out after the liquid phase (droplets) has separated out between the outlet pipes. These isolate the returned liquid from the discharged airflow and thus prevent the collected liquid from being (again) swept away by the exiting airflow. In addition, the collected liquid can flow back into the tank through the ventilation pipe in a controlled manner.

Preferably, the vent hood further includes a collection pan for collected liquid surrounding the vent tube and served by the drain tubes. That is, the drain pipes open into the collection pan. As a result, the liquid can first be temporarily stored in the collection pan before the liquid can flow from the collection pan into the ventilation pipe, for example given suitable pressure conditions in the ventilation hood and in the ventilation pipe.

The collection pan preferably has a capacity of at least two liters, in particular at least three liters. This enables sufficient amounts of air to flow out and sufficient amounts of liquid contained therein to be separated, even in the case of stationary tanks/containers, as are required for the temporary storage of beverages, beverage components or similar foodstuffs in the corresponding production.

Preferably, a dividing wall penetrated by the drain pipes is formed between the ventilation duct and the collecting trough to shield the collecting trough against air flow. This prevents liquid temporarily stored in the collection pan from being entrained again by the outflowing air.

Drainage openings are preferably formed in the venting pipe for draining liquid collected in the collection pan into the venting pipe. Through the drain openings, the collected liquid can drain into the ventilation pipe in a controlled manner, for example at a specific filling level in the collecting trough and/or at a certain pressure difference.

The drainage openings preferably have a clear width, in particular a diameter, of 6 to 10 mm. This promotes a controlled outflow of the liquid when the rising air flow in the vent tube decreases, so that the liquid can flow completely back through the vent tube into the tank. In particular, this also avoids the returning liquid being entrained again by the rising air flow.

The ventilation pipe, the cover and the baffle plate are preferably arranged in relation to one another in such a way that a steam flow/air flow rising in the ventilation pipe is deflected by the cover and the baffle plate by at least 150°, in particular essentially by 180°, and consequently hits the baffle plate. This means that liquid droplets entrained in the air flow / vapor flow as a result of their Loosen the mass inertia during the deflection of the air flow / steam flow and hit the baffle plate. As a result, the liquid phase (droplets) of the air flow / vapor flow is separated from its gas phase and consequently separated.

The baffle plate preferably connects directly to the cover. This means that there is no aerodynamically effective air gap between the baffle plate and the cover. This promotes a particularly effective deflection of the air flow / steam flow and the corresponding separation of liquid droplets on the baffle plate.

The cover and the baffle plate, in particular with the drain pipes connected to the baffle plate, are preferably designed as a detachable insert for insertion between the ventilation pipe and the side wall of the ventilation hood. This simplifies assembly and cleaning of the ventilation hood.

The insert can preferably be detachably fastened to the side wall of the ventilation hood in the area of the cover by means of a form fit, in particular by means of a bayonet catch. This allows easy inspection and, if necessary, cleaning of the ventilation hood.

The stated object is also achieved with a tank according to claim 12, which is designed to operate essentially at ambient pressure and includes a ventilation hood according to at least one of the described embodiments. The tank is preferably a product tank for accommodating liquid foods or components thereof, for example for accommodating beverages or beverage components.

Preferably, the tank also includes spray nozzles for the internal supply of a cleaning liquid and a drain for draining cleaning liquid collected in the ventilation hood out of the tank. This enables the tank to be cleaned efficiently using CIP processes and the cleaning liquid to be recycled, recycled and/or disposed of in an economical and environmentally friendly manner.

The stated object is also achieved with a beverage treatment system according to claim 14, which includes such a tank.

Furthermore, the beverage treatment system can include a CIP system, via which cleaning, sterilizing and/or rinsing agents can be introduced into the tank. For this purpose, the tank and the CIP system are connected via at least one pipe. Furthermore, the beverage treatment system can include a deaerator, a heat exchanger, a filling machine and/or other components for beverage treatment, which are at least indirectly connected to the tank via pipes.

• 1 einen Längsschnitt durch die Entlüftungshaube;
• 2 einen Schnitt durch den fest zu montierenden Grundkörper der Entlüftungshaube;
• 3 einen Längsschnitt durch den als lösbaren Einsatz ausgebildeten Bestandteil der Entlüftungshaube; und
• 4 eine Schrägansicht des Einsatzes.

A preferred embodiment of the invention is shown in the drawing. Show it:

• 1 a longitudinal section through the ventilation hood;
• 2 a section through the main body of the ventilation hood to be fixed;
• 3 a longitudinal section through the part of the ventilation hood designed as a detachable insert; and
• 4 an oblique view of the insert.

As the 1 can be seen, the ventilation hood 1 for mounting on a (schematically indicated) tank 2 comprises a ventilation pipe 3 on which, for example, a flange 3a for fastening the ventilation hood 1 to the tank 2 is formed.

The ventilation hood 1 also comprises a side wall 4 surrounding the ventilation pipe 3, preferably with a circular cross-section, in which at least one screen 5 is formed. The sieve 5 has, for example, such a mesh size that air can escape and the penetration of solid bodies, such as insects or the like, is prevented. Suitable mesh sizes are, for example, in the range from 0.5 to 2 mm.

The ventilation hood 1 also includes a cover 6 which covers the ventilation pipe 3 at the front side and on which a handle 6a, for example, is formed.

The ventilation hood 1 also includes a baffle plate 7 and a drainage channel 8 for catching liquid 9 running off on the inside 7a of the baffle plate 7.

The baffle plate 7 is arranged within the sieve 5 in such a way that the cover 6 and the baffle plate 7 on the one hand and the ventilation pipe 3 on the other hand form an essentially annular ventilation channel 10 running at an angle between them. In this, a steam flow / air flow 11 rising in the ventilation pipe 3 is deflected in such a way that droplets entrained therein in the sense of a liquid phase 11a are driven by centrifugal force when the air flow 11 is deflected, i.e. due to inertia, are guided against the baffle plate 7 and are thus separated from the gas phase flowing onwards 11b of the air flow 11 separate. The remaining gas phase 11b of the air Flow 11 can flow through the annular ventilation channel 10 and the screen 5 into the environment.

As the 1 can also be seen, the ventilation hood 1 includes drain pipes 12, which are connected to the inlet channel 8 and the ventilation channel 10 cross the bottom. This means that the gas phase 11b of the air flow 11 can flow out largely unhindered between the outlet pipes 12 without entraining liquid 9 in the outlet pipes 12 again after it has been separated off. That is, the drain pipes 12 separate the outflowing liquid 9 in terms of flow from the gas phase 11b of the air flow 11.

Below the ventilation pipes 12 there is preferably also a collection trough 13 which can be formed by a bottom section 4a of the side wall 4, for example. The outlet pipes 12 then open into the collection pan 13. The collection pan 13 is located below the screens 5, through which the gas phase 11b can flow out to the outside.

The collection pan 13 preferably has a capacity for the collected liquid 9 of at least 2 liters, in particular at least 3 liters. A sufficient volume of the collected liquid 9 can thus be temporarily stored for CIP processes, for example as long as the air flow 11 is still appreciably rising in the ventilation pipe 3 .

In the 1 It can also be seen that a partition wall 14 is formed between the ventilation channel 10 and the collection pan 13 . This prevents the liquid 9 collected in the collecting tray 13 from being entrained by the gas phase 11b of the air flow 11 flowing above it.

In the 1 drain openings 15 can also be seen, through which the liquid 9 collected in the collection trough 9 can flow back into the ventilation pipe 3 and thus be fed back into the tank 2 . The drain openings 15 preferably have a clear width, in particular a diameter, of 6 to 10 mm. This reduces the backflow of the liquid 9 as a function of the pressure, i.e. as a function of a pressure difference between the collection trough 13 and the interior of the ventilation pipe 3. For example, this can prevent the collected liquid 9 from flowing back into the ventilation pipe 3 as long as there is still an air flow 11 in it , The returning liquid 9 could entrain upwards again.

Like in the 1 is indicated schematically, the air flow 11 is deflected in the region of the cover 6 and the baffle plate 7 by at least 150° and in particular by at least 180° in the vertical direction. This enables a sufficient centrifugal force effect during the deflection, so that droplets contained in the air flow 11 are guided against the baffle plate 7 due to their mass inertia and are deposited there and run down it.

A deflection by at least 180° is to be understood as meaning that the air flow 11 rising essentially vertically in the ventilation pipe 3 is deflected overall at least to such an extent on the cover 6 and on the baffle plate 7 that it then temporarily flows essentially vertically downwards and/or in the ventilation duct 10. or flows obliquely inwards to the vent pipe 3.

The gas phase 11b of the air flow 11 can, in principle, be further deflected after passing through the baffle plate 7 and can thus be guided through the screen 5 to the outside.

This too is in the 1 shown by way of example using an essentially S-shaped flow path in the ventilation channel 10 .

The baffle plate 7 adjoins the cover 6 preferably without any gaps in terms of flow at its upper edge, so that the air flow 11 or its gas phase 11b is conducted completely through the flow channel 10 . This makes it possible to prevent significant portions of the liquid phase 11a from being guided past the baffle plate 7 and leaving the ventilation hood 1 in a different way than that described.

As the 2 and 3 can be seen in the comparison, the ventilation hood 1 is preferably designed essentially in two parts with a base body 1a, which is fixedly mounted on the tank 2, and with an insert 1b, which includes the cover 6, the baffle plate 7, the drain channel 8 and the drain pipes 12 includes.

Correspondingly, the ventilation pipe 3, the side wall 4 with the screens 5 and the collection trough 13 are components of the base body 1a, which is firmly anchored to the tank 2.

The insert 1b can be handled, for example, by the handle 6a of the cover 6 and inserted into the base body 1a. To fasten the insert 1b to the base body 1a, a bayonet catch 16 is provided, for example, whose components 16a, 16b, which are known in principle, are formed on the base body 1a and on the insert 1b, for example in the area of the cover 6.

As the 3 and 4 can be seen in the synopsis, the drain pipes 12 are preferably present in four versions. This then also applies, for example, to the drainage openings 15, the number of screens 5 and/or the number of bayonet locks 16. Such a circumferential distribution of the above components of the ventilation hood 1 enables a simple construction and easy insertion of the insert 1a into the base body 1b .

In principle, however, different circumferential distributions of the individual components described would also be conceivable, for example three, five or six drain pipes 12.

The drainage channel 8 is preferably continuous in the circumferential direction, but could also be segmented in such a way that the separated liquid phase 11a is then collected in one segment of the drainage channel 8 and can flow from there into the collection trough 13 in the respective associated drainage pipe 12 .

The partition wall 14 is preferably part of the base body 1a and can be ring-shaped and/or suitably segmented and/or have openings, so that the drain pipes 12 when

Insertion of the insert 1b are guided through the partition 14 and finally open into the collection trough 13 on the outlet side.

The tank 2 can be any container, for example a kettle, in which a product, for example a drink or similar foodstuff, is stored. Such tanks 2 preferably have a capacity of at least 1 m ³ .

During production operation, the tank 2 is essentially at ambient pressure, ie the tank 2 can breathe in relation to the atmosphere surrounding it to equalize the pressure.

When cleaning the tank 2, which is preferably a CIP process, heated air can rise through the ventilation pipe 3 and is deflected in the ventilation hood 1 in the area of the cover 6 and the baffle plate 7, in particular by at least 180°. The centrifugal force generated in the airflow 11 causes the liquid phase (droplets) 11a contained therein to separate from the gaseous phase 11b of the airflow 11. The liquid 9 separated in this way is collected via the peripheral drainage channel 8 and through the drainage pipes 12 into the lower area of the Ventilation hood 1 and in particular passed into the collection pan 13. This area is fluidically separated from the air flow 11 and thus from the ventilation channel 10 in such a way that separated liquid 9 cannot be entrained by the air flow 11 or its gas phase 11b.

While the air flow 11 is being blown off in the course of cleaning the tank 2, an overpressure temporarily builds up in the tank, which prevents the liquid 9 temporarily stored in the collection pan 13 from being able to flow back through the drain openings 15 into the ventilation pipe 3 and there in turn to the air flow 11 is exposed.

For this purpose, the drain openings 15 are appropriately dimensioned to allow the liquid 9 to flow back in a controlled manner only when the rising air flow 11 has weakened to such an extent that a pressure equalization between the tank 2 and the environment is established. The collected liquid 9 can then flow back into the tank 2 in a controlled manner and can thus be essentially completely returned.

Additional collecting devices and/or drain pipes in the outside area of the tank 2 for liquid 9 contained in the air flow 11 or similar components are therefore unnecessary. In addition, contamination of the liquid 9 is effectively avoided since the separation takes place entirely within the at least one screen 5 . This can be optimized in the sense of an insect protection screen in such a way that there is sufficient air outlet and at the same time no solid bodies that need to be held off, such as insects, for example, can penetrate into the tank 2 .

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• US4889160A [0004]
• FR 2988081 A1 [0005]

Claims (14)

Ventilation hood (1) for a tank (2) operated without pressure, comprising: a ventilation pipe (3) which can be connected to the tank; a side wall (4) peripherally surrounding the ventilation tube and having at least one screen (5) for the escape of air and the prevention of entry of solids; and a cover (6) covering the front side of the ventilation pipe, with a baffle plate (7) with a peripheral drainage channel (8) for catching liquid (9) running off on the inside (7a) of the baffle plate being arranged inside the screen in such a way that the ventilation pipe on the one hand and the cover and the baffle plate on the other hand form an angled ventilation channel (10) between them for the centrifugally driven separation of liquid from an air flow (11)/steam flow on the baffle plate and for subsequent ventilation through the sieve. ventilation hood after claim 1 , further comprising drain tubes (12) connected to the gutter (8) and crossing the vent channel (10) downwards for returning collected liquid (9) from the gutter to the vent tube (3). ventilation hood after claim 2 , further with a collecting tank (3) for collected liquid (9) surrounding the ventilation pipe (3) and supplied by the drain pipes (12). ventilation hood after claim 3 , wherein the collection trough (13) has a capacity of at least 2 liters, in particular at least 3 liters. ventilation hood after claim 3 or 4 , wherein between the venting channel (10) and the collection pan (13) a partition (14) for shielding the collection pan against air flow is formed. Ventilation hood after one of claims 3 until 5 wherein in the vent pipe (3) drain openings (15) for draining in the collection trough (13) collected liquid (9) are formed in the vent pipe. ventilation hood after claim 6 , wherein the drain openings (15) have a clear width, in particular a diameter of 6 to 10 mm. Ventilation hood according to at least one of the preceding claims, wherein the ventilation pipe (3), the cover (6) and the baffle plate (7) are arranged in such a way that an air flow (11)/steam flow rising in the ventilation pipe from the cover and from the baffle plate is rotated by at least 150° , In particular essentially by 180°, is deflected and consequently hits the baffle plate. Ventilation hood according to at least one of the preceding claims, in which the baffle plate (7) directly adjoins the cover (6). Ventilation hood according to at least one of the preceding claims, wherein the cover (6) and the baffle plate (7), in particular with drain pipes (12) connected thereto, are designed as an insert (1b) for insertion between the ventilation pipe (3) and side wall (4). ventilation hood after claim 10 , wherein the insert (1b) in the area of the cover (6) can be detachably fastened to the side wall (4) by means of a form fit, in particular by means of a bayonet catch (16). Tank (2), in particular product tank for accommodating liquid foodstuffs or components thereof, for operation essentially under ambient pressure, with a ventilation hood (1) according to at least one of the preceding claims. tank up claim 12 , furthermore with spray nozzles for the internal supply of a cleaning liquid and with a drain for discharging cleaning liquid (9) collected in particular in the ventilation hood (1) from the tank. Beverage treatment plant with one tank after claim 12 .

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