EP2452149B1 - Plate heat exchanger - Google Patents

Description

Field of the invention

The invention relates to a plate heat exchanger having a plurality of flow channels having plates, wherein a first plate having a front side with at least one flow channel for a first fluid and a second plate has a front with at least one flow channel for a second fluid, and wherein the plates have through holes, via which the flow passages for the same fluid are respectively connected to each other, wherein a front plate, which is upstream of the front of the first plate, connections for the first fluid and for the second fluid, and wherein an end plate forms the conclusion of the juxtaposed plates.

State of the art

In the pharmaceutical, biotechnology and food industry, gaseous or liquid media must often be heated or cooled. To perform such thermal processes, heat exchangers are commonly used. Heat is transferred from the warmer medium to the colder medium. The media are separated from each other. There is a need for Heat exchangers that are very inexpensive in terms of material and manufacturing.

From the DE 10 2006 013 503 A1 a plate heat exchanger with a plurality of flow channels plates is known. A first plate has at least one flow channel for a first fluid and a second plate has at least one flow channel for a second fluid. The plates have through openings through which the flow channels for the same fluid are connected to each other.

The disadvantage here is that the plates are relatively expensive sealed against each other via seals or, as far as they are made of a ceramic material, it is known to join them in a complex process cohesively to a monolithic block. Both devices produced by this method are correspondingly expensive and expensive to manufacture. Another disadvantage is that in the known plate heat exchanger, a separate outflow of condensate is not possible.

From the DE 36 41 458 A1 is a plate heat exchanger, consisting of several with the interposition of seals using pressure plates into a plate package joinable plastic plates, between which adjacent flow gaps are formed, which are successively flowed through plate flow openings alternately by a heat-emitting and heat-absorbing medium, known as Heat transfer plates are used, which are formed as flat plates, between which so-called turbulence plates are arranged, the surfaces of which have turbulence profiles on one or both sides in order to generate flow turbulences in the flow gap or flow channel.
Insofar as the turbulence plates have turbulence profiles only on one side, this results in that in each case a flow gap or flow channel is formed by flat sides without flow profile only by edge seals as spacers, which can lead to a reduction in stability. As far as the turbulence plate has turbulence profiles on both sides, this leads to the fact that although the first plate is easier to produce, but the turbulence plate is correspondingly expensive to produce.
Another disadvantage is also here that in the known plate heat exchanger, a separate outflow of condensate is not possible.

Out EP 0 038 454 A2 is a plate heat exchanger consisting of a plurality of extruded single sheets of polycarbonate known.

The disadvantage here is that the plates have no internal flow distributor or flow straightener. Thus, more expensive components for fluid distribution must be provided. When assembling difficulties arise to ensure a necessary sealing for sterile applications. Even with this known plate heat exchanger, a separate outflow of condensate is not provided.

From the FR 2 184 536 A1 For example, a plate heat exchanger having a plurality of flow channel forming plates is known. A first plate 4a, 4c in this case has a meandering opening 6, which forms a flow channel for a first fluid with two adjacent flat plates 2a, 2b. A corresponding second plate 4b, 4d has a meandering aperture 6 arranged in mirror image, which with two adjacent flat plates 2b, 2c and 2d, 2e has a second flow channel extending parallel to the first flow channel for a second fluid. Through passage openings in the plates, the flow channels for the same fluid are connected to each other. A disadvantage of the known heat exchanger, on the one hand, that the arrangement of the flow channels is relatively limited by the meandering design of the apertures and, secondly, that the apertures having plates must be sealed from both sides. Another disadvantage is in the FR 2 184 536 A1 in that separate drainage of condensate is not possible.

From the DE 199 09 881 A1 a plate heat exchanger is known, which is flowed through by a first and a second fluid, wherein between a front plate and a cover plate, a plurality of stacked plates is arranged, which are partially spaced apart and in contact, so that between them in a heat transfer region flow channels are formed , which are connected to each other for the same fluid. The spacing of the plates is effected by formations which are formed by partially arranged knobs and / or beads. Furthermore disadvantageous in the DE 199 09 881 A1 is that a separate drain of condensate is not possible.

Unlike the DE 199 09 881 A1 has the flow channel of the subject of the application in the vertical direction in the lower part of a plenum, which serves to accommodate condensate, which is discharged separately via a condensate connection.

Also from the EP 1 308 685 A2 a plate heat exchanger is known which can be traversed by two separate media, with stacked plates, which are partially spaced and in regions in contact, so that between each adjacent plates flow channels are formed. In this case, the plates are spaced apart by formations of the plates, wherein over the circumference of the plates successive areas having openings or through openings (via which the flow channels for the same fluid are each connected to each other), alternately formed in the opposite direction from the plane of the plates are. Also at the EP 1 308 685 A2 is disadvantageous that a separate outflow of condensate is not possible.

Also from the EP 0 805 328 A2 a plate heat exchanger is known in which first plates and second plates are stacked, wherein at least one plate surface has a rectilinearly parallel profiling, so that between adjacent plate elements flow spaces of a plurality of rectilinear parallel flow channels are formed, which alternately via inlet and outlet channels with a first and a second fluid can be charged. Also from this document, neither a separate drain of condensate nor a plenum for receiving condensate is known.
Also from the EP 0 203 213 A1 For example, there is known a plate heat exchanger having a plurality of parallel, spaced plates between which flow channels for first and second fluids are formed. Another disadvantage here is that no separate outflow of condensate from a collecting space for receiving the condensate is arranged.

From the WO2008 / 024066 A1 is also known a plate heat exchanger with a plurality of plates, between which formations for forming flow channels are arranged. Although this plate exchanger in the vertical direction down an additional drain for removing the first liquid in the first channel, which is not connected to a separate collection space. A note on the discharge of condensate is also not refer to this citation.

Also from the US 5 538 593 A a plate heat exchanger with a plurality of flow channels plates is known. In this case, a first plate has a front side with at least one flow channel for a first fluid (heated steam) and a second plate has a front side with at least one flow channel for a second fluid (raw liquid). Furthermore, the plates have through openings, via which the flow channels for the same fluid are respectively connected to one another. The front of the first plate is preceded by a front plate having ports for the first fluid and ports for the second fluid. The conclusion The juxtaposed plates is formed by an end plate.

A disadvantage of the known plate heat exchanger that the plates are relatively expensive sealed against each other via seals. Another disadvantage is that no collecting space is provided for the second fluid, can be removed via the condensate separated from the second fluid.

task

Object of the present invention is therefore to provide a plate heat exchanger available, which is simple and inexpensive in terms of material and production and which makes it possible, for example, due to a cooling of gas resulting condensate.

Presentation of the invention

The object is achieved in conjunction with the preamble of claim 1, characterized in that the plates and connections are made of plastic, that the plates are glued or welded tightly together, and that the flow channel for the second fluid in the lower region in the vertical direction a collecting space has, which serves to receive condensate, which is discharged via a arranged on the front plate condensate connection that the communicating with the collecting space through holes for the second fluid of the plates are elongated and with passage openings of the plates correspond, and that these passage openings in their vertically lower portion with the condensate connection and in its vertical upper portion with the connection to the flow channel of the second plates in connection.

The plate heat exchanger according to the invention is simple in construction and can be produced inexpensively by simple production of its plastic plates, for example by injection molding of the plates. By gluing or by connecting the plates in a plastic welding process can be dispensed with seals. The plate heat exchangers can be manufactured so cheaply that they can be used as a disposable heat exchanger. This can be dispensed with a costly cleaning or disassembly. Due to their structure, the plate heat exchangers according to the invention are suitable for applications in the pharmaceutical, biotechnology and food industries. By arranging a collecting space in the vertically lower region of the flow channels, which is connected to a condensate connection, condensate formed, for example, by cooling a gas conducted through the flow channel can be discharged via the condensate connection on the front plate.

Characterized in that the communicating with the collecting space through holes of the plates are elongated and formed in its lower in the vertical direction with the condensate connection and in its upper vertical direction Area are connected to the connection to the flow channel of the second plate, can advantageously be discharged via the same through-openings both the second fluid and its condensate via separate ports.

According to a preferred embodiment of the invention, the plates are flat on their backs facing away from the front sides. This has the advantage that the plates can be strung together in any order.

According to a further preferred embodiment of the invention, the plates on their backs facing away from the front sides of the flow channels of the adjacent front sides corresponding mirror-symmetrical flow channels.

This makes it possible in particular to form the first plates and the second plates of identical construction, wherein the second plates are mounted relative to the first plates turned by 180 °. As a result, only one mold is needed for the first and second plate, which considerably simplifies the production.

According to a preferred embodiment of the invention, the flow channels of the plates each have flow straighteners. The flow straighteners are designed as barriers or partitions arranged in the flow channels. The dividing walls of flow channels for the first fluid and of flow channels for the second fluid are preferably arranged perpendicular to one another. This contributes to a better heat exchange.

According to a further preferred embodiment of the invention, the plates and connections are formed from a sterilizable plastic. This makes it possible to deliver the plate heat exchangers sterile packed.

As far as the plates and terminals are made of polycarbonate (PC), polyethylene terephthalate (PET), acrylonitrile-butadiene-styrene (ABS), polyphenylene ether (PPE) or polyphenylene sulfide (PPS), the plate heat exchangers are sterilizable by irradiation with gamma or beta rays become. It is also possible to sterilize the plate heat exchangers by autoclaving with superheated steam.

According to a further preferred embodiment of the invention, the plate heat exchanger is connected to a bioreactor, which is preferably also sterilizable.

Thus, for exhaust gas cooling of a gas to be discharged from the bioreactor, the connection for the inlet of the first fluid can be connected to an exhaust pipe of the bioreactor and the connection for the outlet of the first fluid can be connected to an inlet of a sterile filter, while the connections for the second fluid are connected to a cooling circuit can be.

Liquid vapors taken up during the gassing of the bioreactor are condensed and the condensate is returned to the bioreactor, and the dried waste gas can now be discharged via a sterile filter without being blocked by condensed liquid.

According to a further preferred embodiment of the invention, for preheating a medium to be fed to the bioreactor, the inlet for the first fluid is connected to a medium supply line for supplying the medium and the exit point for the first fluid is connected to an inflow port of the bioreactor the second fluid is connected to a temperature control circuit. As a result, in particular long heating times of the filled bioreactor can be avoided.

In the following detailed description and the accompanying drawings, preferred embodiments of the invention are exemplified.

Brief descriptions of the drawings

Figur 1:

eine räumliche Darstellung eines Plattenwärmetauschers als Explosionszeichnung, welcher nicht unter den Schutzbereich der Ansprüche fällt,

Figur 2:

eine Vorderansicht einer Platte eines Plattenwärmetauschers in einer weiteren bevorzugten Ausführungsform mit einem Strömungskanal für ein erstes Fluid,

Figur 3:

eine Rückansicht der Platte von Figur 2,

Figur 4:

eine Vorderansicht einer Frontplatte eines Plattenwärmetauschers mit Anschlüssen für ein erstes Fluid, für ein zweites Fluid sowie einem Kondensatanschluss,

Figur 5:

eine Rückansicht der Frontplatte von Figur 4 mit einem Strömungskanal für ein erstes Fluid, der spiegelsymmetrisch zu dem Strömungskanal von Fig. 2 ausgebildet ist,

Figur 6:

eine Vorderansicht einer Abschlussplatte eines Plattenwärmetauschers mit einem Strömungskanal für ein erstes Fluid,

Figur 7:

eine schematische Darstellung eines Prozessschemas eines Bioreaktors in Verbindung mit einem Wärmeplattentauscher, der als Abgaskühler ausgebildet ist, und

Figur 8:

ein Prozessschema eines Bioreaktors in Verbindung mit einem Plattenwärmetauscher als Medienbeheizung zur Vorwärmung beim Befüllen des Bioreaktors.

In the drawings show:

FIG. 1:

a spatial representation of a plate heat exchanger as an exploded view, which does not fall under the scope of the claims,

FIG. 2:

a front view of a plate of a plate heat exchanger in a further preferred embodiment with a flow channel for a first fluid,

FIG. 3:

a back view of the plate from FIG. 2 .

FIG. 4:

a front view of a front plate of a plate heat exchanger with connections for a first fluid, for a second fluid and a condensate connection,

FIG. 5:

a rear view of the front panel of FIG. 4 with a flow channel for a first fluid which is mirror-symmetrical to the flow channel of Fig. 2 is trained,

FIG. 6:

a front view of a closure plate of a plate heat exchanger with a flow channel for a first fluid,

FIG. 7:

a schematic representation of a process diagram of a bioreactor in conjunction with a heat plate exchanger, which is designed as an exhaust gas cooler, and

FIG. 8:

a process diagram of a bioreactor in conjunction with a plate heat exchanger as media heating for preheating during filling of the bioreactor.

Description of the embodiments

A plate heat exchanger 1 essentially consists of a plurality of first plates 40 and second plates 50 with flow channels 4, 5, a front plate 6 and an end plate 7.

The first plate 40 has a front side 2 and a back side 41. In the vertical direction, the first plate 40 in its lower left and upper left corners through openings 8, 9 for a first fluid. On the front side 2 of the plate 40, a flat depression is arranged, which forms the flow channel 4 and extends into the passage openings 8, 9. The flow channel 4 has in the horizontal direction from the side walls forth flow barriers 10, 11 of a flow director 12, which overlap in the horizontal direction and thus form a meandering flow channel 4. The back 41 is flat, that is without a flow channel formed.

Outside the flow channel 4, the first plate 40 in the vertical direction at the top right and bottom right through openings 13, 14, respectively.

The second plate 50 has on its front side 3 a flat depression which forms the flow channel 5 and extends into the right through openings 17, 18. The flow channel 5 has flow barriers 15 running in the vertical direction, which form a flow straightener 16. In the left corners, the plate 50 outside the flow channel 5 through holes 19, 20, which with the Through holes 8, 9 of the plate 40 correspond. Correspondingly, the passage openings 17, 18 of the plate 50 correspond to the passage openings 13, 14 of the plate 40. The plate 50 has a rear side 51 facing away from its front side 3, which is flat and thus has no flow channel.

The plate heat exchanger 1 has on its front side the front plate 6 with its connections 21, 22 for the first fluid and connections 23, 24 for the second fluid. In this case, the connection 21 communicates with the passage openings 8, 19 and serves to supply the first fluid, which is discharged via the connection 22, which is in communication with the passage openings 9, 20.

The front panel can be optional on its in FIG. 1 not shown back have a flow channel 4 '.

The port 23 communicates with the through holes 14 and 18 and serves to supply the second fluid, while the port 24 communicates with the through holes 13 and 17 and is used to discharge the second fluid.

The plate heat exchanger 1 is closed at its end facing away from the front panel 6 by the end plate 7. The end plate 7 may have a flow channel 4 in this embodiment and has no through holes in this embodiment.

In an embodiment of the end plate 7, not shown, this is identical to the front plate 6 and is arranged in the plate heat exchanger 1 mirror-symmetrical to the front panel 6.

The front of the end plate can be like in the FIG. 1 However, it may also be flat and thus be formed without a flow channel 4 and may furthermore have passage openings, not shown, which correspond to the passage openings of the plates 40 and 50.

In a particularly preferred embodiment, the front plate 6 and the end plate 7 are each provided with through holes to increase the cross section of the fluid supply, without having to change the sizing of the terminals 21, 22, 23 and 24. In this way, the pressure loss during inflow and outflow of the fluids into and out of the heat exchanger 1 can be minimized in a particularly advantageous manner.

The plates 40 and 50 are at their backs, as explained above, each flat, while the back of the front panel 6 and / or the front of the end plate 7 may be formed flat or alternatively may have a flow channel 4, 4 '. The plates 40, 50, 6 and 7 are each glued to their adjacent plate.

The embodiment of FIG. 2 shows a plate 40 'and 50' with a flow channel 4 'on its front side 2' for a first fluid, which is formed for example as a cooling medium.

In the vertical direction, the first plate 40 'and 50' in their lower left and upper left corners through openings 8 ', 9' for the first fluid. On the front side 2 'of the plate 40', the flow channel 4 'is arranged, which is in communication with the passage openings 8', 9 '. Outside the flow channel 4 ', the side 2' in the vertical direction at the top and bottom right each of the through holes 13 ', 14'.

The back 41 'of the first plate 40' (see FIG. 3 ) has a flow channel 5 'for a second fluid.

The plate 40 'and the plate 50' are exactly identical. Analogous to the in FIG. 1 As shown, the plates 40 'and 50' can be assembled into a plate heat exchanger, with the plates 50 'being mounted facing the identical plates 40', turned through 180 °. Unlike the embodiment according to FIG. 1 in which the back faces of the plates 40 and 50 are each plane, this assembly results in a plate heat exchanger 1, in which the front and the back of the composite plates 40 'and 50' each have a flow channel 4 'and 5'.

In the lower region in the vertical direction, the flow channel 5 'on a collecting space 25 which serves to receive condensate, which via a condensate connection 26 which on the front plate 6' (see FIG. 4 ) is arranged, is discharged. The passage openings 13 'and 14' for the second fluid of the plate 50 'are elongated and correspond to passage openings 13', 14 'of the plate 40' (see FIG. 2 ).

The back 51 'of the plate 50' (see FIG. 3 ) has a flow channel 4 'of another identical plate 40' or the flow channel 4 'of an end plate 7' corresponding flow channel for a first fluid.

The plate heat exchanger 1, 1 'according to the embodiments of the FIGS. 1 to 6 are made of polycarbonate (PC). They are readily gamma-irradiated and are suitable for any sterile application in the temperature range up to 110 ° C, for a short time even up to 125 C. Thus, the heat plate exchanger 1, 1 'can also be sterilized with superheated steam.

According to the embodiment of the FIG. 7 the plate heat exchanger 1 'is connected to a bioreactor 27' and is used as an exhaust gas cooler. The exhaust gas is introduced from the head space 28 of the bioreactor 27 'via an exhaust pipe 29 connected to the port 23' of the plate heat exchanger 1 'at the top of the plate heat exchanger 1'. In the plate heat exchanger 1 ', the gas flow over the flow channel 5' over the individual front sides 3 'of the plates 50' is divided. At the front of the plates 3 'of the plates 50', the gas stream is cooled when flowing down the plate wall and discharged through the port 24 'and further discharged through a sterile filter 30 to the environment. By the exhaust gas cooling in the plate heat exchanger 1 ', the humidity of the exhaust gas is lowered, wherein the liquid medium taken in the bioreactor condensed, discharged via the condensate connection 26 and the bioreactor 27' is fed via a peristaltic pump.

In countercurrent thereto, cooling medium is introduced from the primary cooler 33 from below via the connection 21 'into the plate heat exchanger 1'. From the through holes 8 ', the cooling medium is introduced into the individual flow channels 4' and absorbs the heat from the plates 40 'and 50'. The cooling medium heats up. The cooling medium is collected in the passage opening 9 'and conveyed back into the primary cooler 33 via the connection 22'. The cooling medium is circulated.

According to the embodiment of FIG. 8 the plate heat exchanger 1 is connected to the bioreactor 27 via a feed line 31. In this case, the plate heat exchanger 1 is used to pre-heat the bioreactor 27 to be supplied medium.

The medium to be heated is introduced from a reservoir, not shown, in the plate heat exchanger 1 from above via the terminal 23. In the plate heat exchanger 1, the material flow over the resulting from the through holes 14 and 18 flow distributor in the individual channels 5 distributed. In the flow straighteners 12, the media stream is warmed up when flowing down the plate wall. The media streams are merged and directed to the output or port 24. From port 24, the preheated medium is fed into the bioreactor 27.

In countercurrent thereto, heating medium is introduced from below by a thermostat 32 via the connection 21 into the plate heat exchanger 1. In the resulting from the through holes 8 and 9 flow distributor, the heating medium is introduced into the individual channels 4 and gives the heat to the plates 40 and 50 from. The heating medium is conveyed from the outlet or from the connection 22 back into the thermostat 32. The heating medium is circulated.

Claims (15)

1. A plate heat exchanger (1, 1') comprising a plurality of plates (40, 40', 50, 50') having flow channels (4, 4', 5, 5'), wherein a first plate (40, 40') has a front side (2, 2') with at least one flow channel (4, 4') for a first fluid and a second plate (50, 50') has a front side (3, 3') with at least one flow channel (5, 5') for a second fluid, and wherein the plates (40, 40', 50, 50') have through openings (8, 8', 9, 9', 13, 13', 14, 14', 19, 20) by which the flow channels (4, 4', 5, 5') for the same fluid are connected to each other,
   wherein a front plate (6, 6'), which is placed in front of the front side (2, 2') of the first plate (40, 40'), has ports (21, 21', 22, 22', 23, 23', 24, 24') for the first fluid and for the second fluid, and wherein an end plate (7, 7') forms the end of the serially arranged plates (40, 40', 50, 50', 6, 6'), wherein the flow channel (5') for the second fluid has a collector (25) in the lower region in the vertical direction that is used for receiving condensate, which can be discharged through a condensate port (26),
   characterized in that
   the plates (40, 40', 50, 50', 6, 6', 7, 7') and ports (21, 21', 22, 22', 23, 23', 24, 24') are formed from plastic,
   that the plates (40, 40', 50, 50', 6, 6', 7, 7') are bonded or welded to one another with fluid tight seals,
   that the through openings (13', 14') for the second fluid of the plates (50') that are connected to the collecting space (25) have an elongated design and correspond to through openings (13', 14') of the plates (40'), and
   that these through openings (13', 14') are connected to the condensate port (26) in their lower region in the vertical direction and to the port (24') on the flow channel (5') of the second plates (50') in their upper region in the vertical direction.
2. The plate heat exchanger according to claim 1,
   characterized in that
   the end plate (7, 7') has through openings corresponding to the through openings (8, 8', 9, 9', 13, 13', 14, 14', 19, 20) of the plates (40, 40', 50, 50').
3. The plate heat exchanger according to either of claims 1 or 2,
   characterized in that
   the rear side of the front plate (6, 6') has a flow channel (4, 4').
4. The plate heat exchanger according to any of claims 1 to 3,
   characterized in that
   the front side of the end plate (7, 7') has a flow channel (4, 4').
5. The plate heat exchanger according to any of claims 1, 2 or 4,
   characterized in that
   the rear side (61, 61') of the front plate (6, 6') is flat.
6. The plate heat exchanger according to any of claims 1 to 3 or 5,
   characterized in that
   the front side of the end plate (7, 7') is flat.
7. The plate heat exchanger according to any of claims 1 to 6,
   characterized in that
   the plates (40, 50) have a flat design on their rear sides (41, 51), which face away from the front sides (2, 3).
8. The plate heat exchanger according to any of claims 1 to 6,
   characterized in that
   the plates (40', 50', 6', 7') have on their rear sides (41', 51', 61') that face away from the front sides (2', 3') mirror-symmetrical flow channels (4', 5') corresponding to the flow channels (4', 5') of the adjacent front sides (2', 3').
9. The plate heat exchanger according to claim 8,
   characterized in that
   the first plates (40') and the second plates (50') are configured structurally identical, and that the second plates (50') are mounted, correspondingly turned by 180°, opposite to the first plates (40').
10. The plate heat exchanger according to any of claims 1 to 9,
    characterized in that
    the flow channels (4, 4', 5, 5') have a flow guide (12, 16).
11. The plate heat exchanger according to any of claims 1 to 10,
    characterized in that
    the plates (40, 40', 50, 50', 6, 6', 7, 7') and ports (21, 21', 22, 22', 23, 23', 24, 24', 26) are formed from a sterilizable plastic.
12. The plate heat exchanger according to any of claims 1 to 11,
    characterized in that
    the plates (40, 40', 50, 50', 6, 6', 7, 7') and ports (21, 21', 22, 22', 23, 23', 24, 24', 26) can be irradiated with gamma and/or beta rays and/or can be autoclaved with superheated steam.
13. An assembly consisting of a bioreactor (27, 27') and a plate heat exchanger according to any of claims 1 to 12,
    characterized in that
    the plate heat exchanger (1, 1') is connected to the bioreactor (27, 27').
14. The arrangement according to claim 13,
    characterized in that
    for the exhaust gas cooling of a gas to be discharged from the bioreactor (27'), the port (23') for the entry of the second fluid is connected to an exhaust gas line (29) of the bioreactor (27') and the port (24') for the exit of the second fluid is connected to an inlet of a sterile filter (30), and
    that the ports (21', 22') for the first fluid are connected to a cooling circuit.
15. The arrangement according to claim 13,
    characterized in that
    for the preheating of a medium which is to be fed to the bioreactor (27), the port (23) for the entry of the second fluid is connected to a medium supply line (31) for supplying the medium and the port (24) for the exit of the second fluid is connected to an inflow port of the bioreactor (27), and
    that the ports (21, 22) for the first fluid are connected to a temperature control circuit.

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