This invention relates to heat recovery devices and can be used when heat exchange between gas media with low pressure (1-2 bar) and low pressure loss requirement (up to 1-2 kPa) is needed, including, but not limited to, refrigeration systems (refrigerators, freezers, rapid chilling systems, A/C and/or indoor temperature control systems) and other systems based on air cycle refrigeration that cannot operate without heat exchange equipment.

A heat exchanger (HE) is a system wherein heat exchange between two media of different temperature occurs.

Advantages of the claimed heat exchanger as compared to the known heat exchange systems can be conveniently illustrated by one of its applications, e. g. in air cycle refrigeration systems for air-to-air heat exchange.

An air cycle refrigeration system (ACRS) is a type of refrigeration system wherein air is used as a working medium. These are closed cycle systems. Air enters a compressor and undergoes adiabatic compression with a rise in temperature. Then, compressed air is cooled by coolers (mostly heat exchangers using ambient air or cold return flow) and sent to an expander where it undergoes adiabatic expansion with cooling. Cooled air is sent to the object to be cooled, interacts with it and goes back to the compressor.

ACRS's have the following distinctive features:

1) . Reduced energy usage. The energy of compressed air is used to rotate the expander. If the expander and the compressor use the same shaft, the energy used to rotate the compressor is partially compensated.

2) . Safety for the environment, ease of maintenance. Unlike toxic refrigerants currently in use (e. g. widely-used aliphatic saturated fluorine-containing hydrocarbons), air used as a refrigerant is not toxic. It means ACRS's are environmentally clean refrigeration systems.

3) . Safety. The refrigerant used in the system is not explosive or inflammable, unlike other refrigerants in use (e. g. ammonia, propane, butanes and other hydrocarbons). The operating pressure does not exceed 1 bar (g) making ACRS's safe for use in refrigeration systems.

One of the solutions to the problem of cooling air flowing from the compressor to the expander is the arrangement of heat exchange with the cold air exiting the cold room. This application is described in prior art as a "counter- flow plate fin type heat exchanger and ACRS for containers" (patent application JP 2010025438 A, IPC F28D9/02, F25B9/00 published on 04/02/2010). Said document discloses, among other tilings, an ACRS wherein a compressor and an expander are mounted on a single shaft and compressed air is cooled in a heat exchanger using a flow of return air from a cold room. In a description to this patent application, the authors indicate the key problem of heat exchange in such ACRS's, i. e. the need for high efficiency of heat exchange and minimum pressure loss.

Said prior art describes a counter- flow plate fin type HE that represents a set of corrugated plate-shaped fins disposed parallel to one another and separated by smooth plate-shaped fins. The plate-shaped fins are assembled by welding. The pattern of flow separation into channels is not described in said invention, i. e. it needs extra design efforts. The claimed solution does not require welding during assembly while the issue of flow separation into channels (between the plates) is resolved by using seals.

Known prior art includes various HE designs.

Summarizing information on the existing types of counter-flow plate heat exchangers, one can single out the following groups:

- Non-pressure heat exchangers that ensure heat exchange between flows of media with a difference in pressure of less than 1 kPa; specifications for such systems indicate losses in % depending on the actual pressure difference. Said heat exchangers cannot ensure reliable separation of media even if the pressure difference in small. In certain cases they cannot even ensure separation of the media and the ambient environment.

- High pressure heat exchangers that ensure heat exchange between media at a high pressure difference; they are frequently welded, half-welded or brazed. They can withstand a pressure differential of up to 30 bar or more. Such systems ensure impermeability (separation of media from one another and from the ambient environment) and are highly efficient (approach temperature of up to 4 °C). As a rule, these heat exchangers are quite expensive due to the labor- intensiveness of the welding and brazing processes while the need for a new die for each standard plate size limits the capabilities of custom production.

HE's similar to the claimed solution are well described in prior art. Known prior art includes a HE for gases of widely differing temperatures (German patent DE 3146089 Al, IPC F28D7/06, F28F1/08 published on 07/07/1983). It describes a matrix consisting of multiple channels formed by U-shaped tubes and a separator of media flows into separate channels. This design is intended for high temperatures and is very complicated: its components have an irregular shape and are to be assembled by welding (brazing). Flows of heat transfer agents pass through multiple turns and are restricted in the inlet/outlet connections significantly increasing flow resistance of the heat exchanger. Counter-flow is not arranged making the heat exchanger significantly less efficient even if the media flowrate is identical. This is also the reason why this design cannot be used for recuperative heat exchangers in ACRS's.

Known prior art includes a HE for heat exchange between gases and/or liquids (German utility model DE 202004000505 Ul , IPC F28D9/00, F28F3/04 published on 22/04/2004). 22/04/2004). It describes a HE wherein gas/gas or gas/fluid flows are separated by plates while the counter- flow of heat transfer media is arranged via turning the flow using complex profile components that adversely impact the flow resistance of the heat exchanger. The heat transfer fluid (gas) is in complex welded (brazed) panels with profile components welded onto them This design is highly complicated and material- and labor-intensive.

Known prior art includes an embossed regenerator matrix for HE (American patent US 6892795 Bl, IPC F28D 19/04, F23L 15/02, F23L 15/00, F28D 17/00, F28D 19/00, published on 17/05/2005). Said patent describes a rotating regenerator matrix comprising an embossed plate wound about an axis so as to form a roll wherein channels are formed by ribs disposed between the layers of the roll used for the passage of hot and cold gas. The solution is designed for ventilation and A/C systems to recuperate heat and moisture and cannot be operated at a high difference of pressure between the flows (over several hundred Pa) as in this case separation of media from one another and from the ambient environment is very challenging.

Known prior art includes a plate heat exchanger, process for manufacturing a plate heat exchanger and ceramic fiber reinforced composite material (European patent EP 1544565 A3, IPC F28F 19/02, F28F 3/04, C04B 41/00, C04B 37/00, F28F 21/04, C04B 35/80, F28D 9/00, C04B 35/573 published on 22/06/2005). This solution represents a HE designed for high temperature (about 1,000 °C) and can be used for counter-flow applications. The HE comprises complex-shaped ceramic plates that form channels for heat transfer agents when they are mounted into a pack. Manufacturing ceramic plates is a highly labor-intensive process. The design uses composite materials and is to be applied in aggressive media while its components are hard to manufacture. The use of this solution in ACRS's is unpractical due to its extreme manufacturing complexity and, consequently, its high cost.

Known prior art includes a heat transfer plate pack and its utilization in regenerative heat exchangers (American patent US 5318102 A, IPC F28D 19/04, F28D 19/00 published on 07/06/1994). This solution comprises three types of plates with each type having parallel ridges. The plates alternate in such a way that the ridges of adjacent plates are disposed at an angle to one another. It creates channels between adjacent plates where hot and cold media flow. This solution is used for preheating air by the heat of exhaust gas. In this application, there is no need for using a seal between media with a significant pressure difference, and small leaks or transfers of fluids are also possible. Due to the indicated operational aspects, said heat exchanger cannot be used in ACRS's as it cannot ensure high-quality sealing between media wilh a significant pressure difference.

Known prior art includes a ribbed recuperative heat exchanger (Russian patent RU 2578374 CI, IPC F28D 9/00, F28F3/08 published on 27/03/2016). Said recuperative heat exchanger comprises at least two modules: central and peripheral modules wherein the central module is "inserted" into the center of the peripheral module. The modules represent channel matrices. Flows of hot and cold media, including gas, move through the channels of different modules perpendicular to one another. As this invention relates to the area of crossflow recuperative heat exchangers, high performance of heat energy regeneration required for the efficient ACRS operation is impossible to achieve, and the use of this solution as a recuperative heat exchanger in ACRS's is unpractical.

Known prior art includes a plate and shell HE (Russian patent RU 22068 1 CI , IPC F28D9/00, F28F3/08 published on 27/04/2006). In this solution, plates are also joined using the labor-intensive process of welding, and, to ensure operation at high temperature and pressure difference, one of the flows is directed into a massive body. In the claimed solution, however, HE has no body, and medium is directly sent to the HE channels from the channel connected to the flange. The labor-intensive process of welding is not used.

Therefore, in spite of the large number of various HE designs, all of them have certain drawbacks. The applicant has no knowledge of a HE design that would ensure minimum loss of hydraulic pressure, high performance of heat exchange and reliable sealing of connections, without excessive complexities of HE design or the manufacturing process.

Thus, many HE's dictate the need for using dies for plate molding, with each plate type requiring a separate die and production line. Therefore, the manufacturing process and the changes in plate dimensions or geometry present a challenge resulting from the need for new dies.

Another serious drawback of many plate HE's is the need for making openings for different flows in the plates. It results in a major excessive use of materials and a high amount of waste that needs to be further processed and recycled.

Currently, the applicant has no knowledge of a simple and reliable design that would stand between high pressure HE's— complex and expensive designs— and no-pressure HE's that are simple, but cannot ensure impermeability of flows with a pressure difference of over 1 kPa.

The purpose of the present invention is the construction of a high-performance HE where drawbacks of known prior art would be eliminated.

The proposed solution is achieved as follows:

One of the embodiments is a heat exchanger comprising a set of plates separated by resilient seals and disposed between two body parts, and inlet and outlet flanges for the first and second media disposed perpendicular to the plate ends wherein:

Plates have bulges and resilient seals are installed along the entire perimeter of the plates, with the exception of gaps in places of medium inlet and outlet;

Even-numbered plates have gaps in resilient seals on two opposing sides that form inlet and outlet for the first flow; uneven-numbered plates have gaps in resilient seals on the other two opposing sides that form inlet and outlet for the second flow. The flows are separated by the resilient seals;

The ends of the plates have end sealing in the flange connection areas.

The claimed heat exchanger wherein:

One of the sides of uneven-numbered plates that has gaps in the resilient seal has another gap in the resilient seal that forms an inlet for the second flow whereas the opposing side has a gap in the resilient seal that forms an outlet for the second flow, with the outlet shifted relative to the inlet on the opposing side of the plate.

The claimed heat exchanger wherein:

One of the sides of uneven-numbered plates that has gaps in the resilient seal has additional gaps in the resilient seal that form the first inlet and the first outlet for the second flow whereas the opposing side has gaps in the resilient seal that form the second inlet and outlet for the second flow.

Another embodiment is a heat exchanger comprising a set of plates separated by resilient seals and disposed between two body parts, and inlet and outlet flanges for the first and second media disposed perpendicular to the plate ends wherein:

Plates have bulges and resilient seals are installed along the entire edge of the plates, with the exception of gaps in places of medium inlet and outlet;

Even-numbered plates have gaps in resilient seals on two opposing sides that form inlet and outlet for the first flow; uneven-numbered plates have gaps in resilient seals on the same two sides as the even-numbered plates, with these gaps forming inlet and outlet for the second flow;

The flows are separated by the resilient seals;

The ends of the plates have end sealing in the flange connection areas.

The claimed heat exchanger wherein:

Uneven-numbered plates have two gaps in the resilient seal on each side that form two inlets and two outlets for the second medium, with the gaps in the resilient seal made in such a way that when uneven-numbered plates are laid upon even-numbered plates the inlet for the first medium flow is located between the inlets for the second medium flows and the outlet for the first medium flow is located between the outlets for the second medium flows.

The claimed heat exchanger wherein:

Even-numbered plates have two gaps in the resilient seal on each side that form two inlets and two outlets for the first medium, with the gaps in the resilient seal made in such a way that when uneven-numbered plates are laid upon even-numbered plates the inlet for the second medium flow is located between the inlets for the first medium flows and the outlet for the second medium flow is located between the outlets for the first medium flows.

Another embodiment is a heat exchanger comprising a set of plates separated by resilient seals and disposed between two body parts, and inlet and outlet flanges for the first and second media disposed perpendicular to the plate ends wherein:

Plates have bulges and resilient seals are installed along the entire perimeter of the plates, with the exception of gaps in places of medium inlet and outlet;

Even-numbered plates have gaps in resilient seals on two opposing sides that form inlets and outlets for the first flow; uneven- numbered plates have additional gaps in resilient seals on the same two sides as the even-numbered plates, with these gaps forming additional inlets and additional outlets for the second flow, and also have gaps on the other two opposing sides that form inlets and outlets for the second medium flow;

The flows are separated by the resilient seals;

The ends of the plat s have end sealing in the flange connection areas.

The claimed heat exchanger wherein:

One of the sides of uneven-numbered plates that differs from the sides of even-numbered plates having gaps in the resilient seal has a gap in the resilient seal that forms an additional inlet for the second flow whereas the opposing side has a gap in the resilient seal that forms an additional outlet for the second flow, with the outlet shifted relative to the inlet on the opposing side of the plate.

The claimed heat exchanger wherein:

One of the sides of uneven-numbered plates that differs from the side of even-numbered plates having gaps in the resilient seal has gaps in the resilient seal that form the first additional inlet and the first additional outlet for the second flow whereas the opposing side has gaps in the resilient seal that form the second additional inlet and additional outlet for the second flow.

Any embodiment of the claimed heat exchanger wherein:

The set of plates is fastened by ties comprising a pin and two tying members wherein the pin penetrate all plates in the set, perpendicular to the plate surface.

The design of the seal unit for any embodiment of the heat exchanger wherein: Areas of flange connections along the plate edge have furrows with grooves inside that have an area that is less than the area of the furrows;

The resilient seal is a tape that is wider than the maximum bulge height;

In the area of furrows, the resilient seal is installed on the plate surface along the furrow edge and covers the grooves in such a way that when the set of plates is compressed the excessive tape is squeezed out into the grooves and joins the resilient seals of adjacent plates, thus forming a solid end sealing in the areas of flange connections.

The character of the present invention is as follows.

In ACRS's of the type described above that are regarded as the key field of application for the present invention, one of the flows (hot flow with elevated pressure) travels from the compressor; as it has a higher pressure and, consequently, a higher density, its speed is lower; therefore, this flow generates less losses in the channels of identical geometry providing for the capability to turn it.

The claimed solution separates the flows by sending one of the flows through HE without turns and sending the other flow (with higher pressure) through HE with a turn. It minimizes the total losses for the two flows and maximizes performance of the entire system without excessive design complexities.

Another advantage of the present invention is the significant increase of the stock utilization ratio and a significant reduction in the amount of waste.

Yet another advantage of the present invention is the simplicity of the manufacturing process, both in greater volumes, e. g. by molding using universal dies, and in small batch runs for various forms and dimensions of the heat exchanger plates with no need for new dies.

In addition to the above, the present invention also reduces HE dimensions by turning one of the flows and maximizing use of the HE plate area.

An important advantage of the present HE is the design of the seals that provides for the significant reduction in the system's weight and dimensions.

The original design of the flow directions has resulted in performance growth.

The above features and advantages as well as other benefits of the present invention that are evident for an expert and means and methods of achieving said benefits will be further clarified in the following description of the various methods and forms of invention embodiments with references to drawing views wherein:

Fig. l a shows a general view of the HE plate design.

Fig. lb shows a general view of the HE plate design.

Fig. 2 shows a general view of the HE plates.

Fig. 3 shows a view of the HE sealing.

Fig. 4 shows a flowchart of sealing installation on two types of HE plates.

Fig. 5 shows a general view of the HE.

Fig. 6 shows the direction of flows inside HE (preferred embodiment).

Fig. 7 shows an alternative option of flow direction inside HE.

Fig. 8 shows an alternative option of flow direction inside HE.

Fig. 9 shows an alternative option of flow direction inside HE.

Fig. 10 shows an alternative option of flow direction inside HE.

Fig. 1 1 shows an alternative option of flow direction inside HE.

Review the preferred embodiment of the present invention.

It should be pointed out that the claimed invention can have multiple embodiments that have a single inventive concept and common industrial design and provide for the solution of the original task. The key difference between all embodiments is the different directions of flows inside HE. In terms of the technical arrangement, all embodiments are identical. Below is a detailed description of the preferred embodiment of the claimed invention while other embodiments are described briefly and can be constructed similarly to the preferred embodiment.

Plates of the claimed HE are of major interest. Two types of plates (Fig. 1) 101 H 102 have identical shape (Fig. 2), but differently disposed bulges 103, 104. In the preferred embodiment, bulges 103, 104 are disposed in shifted rows although other options are also possible. In this case, bulges 103, 104 are only designed to separate plates 101 and 102 so mat the required distance is maintained between the plates in case of compression. The location of bulges 103, 104 on each of the two types of plates 101 and 102 must leave channels for air flows and minimize pressure loss.

Firstly, this approach drastically reduces the complexity and cost of pre-production processes as it eliminates the need for manufacturing a die for an entire plate; a simple tool for making bulges is all that is needed. This is very important for custom and small batch production. For greater volumes, a compound die can be easily manufactured — it is a plate with a number of openings and inserted punches (or matrices on an adjacent plate) made by turning. When this die wears out, it can be repaired by replacing the above parts.

Secondly, the location of bulges on plates and the plate geometry can be changed; using a single tool, one can produce heat exchanges for various conditions (pressure difference, flowrates, performance).

Finally, the claimed approach eliminates the need to use flat intermediate plates that make HE a lot heavier.

Plates 101 and 102 have identical shape before bulges 103, 104 are made (see Fig. 2 for preferred shape). The preferred plate shape is a rectangular parallelepiped. In the preferred embodiment, openings 201 are made in the middle of the longer sides to be used for inserting the tie pins. Each plate has small, preferably rectangular furrows 202 for the installation of flanges 303 along the edge. Two adjacent furrows 202 form channels 203 to be used for the inlet of flows after HE is assembled. Sealing 301 (e. g. a double sided stick tope) is installed along the edge of each plate in a certain manner (to be reviewed below). The main requirement as to sealing 301 is that its thickness (in non-compressed state) should not exceed the height of bulges 103 and 104. Other resilient seals may be used in place of a sealing tape.

An important feature of the present HE is that flows are separated by only installing the seal differently on the two types of plates (see Fig. 4). On one of the plates the seal is applied in such a way that the longer sides of the plate have the seal 301 applied continuously while the shorter side of the plate has a gap with no sealing in the middle that forms channel 203. Another plate has two channels 203 on the longer sides formed by the gaps in seal 301.

However, as indicated below, alternative flow direction inside HE is possible resulting in a different location and number of medium inlet and outlet flanges. However, as indicated above, the form of the plates can be easily changed by changing the location of the bulges and the sealing application procedure. On Fig. 6, one can see that in the preferred embodiment channels 203 on different plate types form ducts for cold air (inlet 502, outlet 503) and hot air (inlets 504, outlets 505).

Fig. 3 shows a detailed view of the seal assembly on sheet 102 (inlet of the flow from the compressor) subject to separate requirements within the present application.

Small grooves 302 are made in furrows 202, closer to the furrow edges, in the area of furrows 202 along the plate edges. Seal 301 is applied to the plate edge to cover grooves 302. When compressed (to be described below), seal 301 is squeezed out into groove 302 coming into contact with the seals of adjacent (upper and lower) plates. Therefore, compression of a set of alternating plates 101 and 102 creates solid continuous sealing (see Fig. 5) in the area of flange 303 connection at the end of plates 101 and 102. Currently, the applicant has no knowledge of similar solid sealing at the ends of HE plates that would not cause a significant increase in the weight and dimensions of the entire system. It ensures an acceptable level of sealing (coupled with similar sealing 304 on flange 303) at minimum cost, without the need for complex adapters. Thus, when the claimed design was tested, HE maintained pressure that was several times higher than the atmospheric pressure, for 24 hours, with no registered losses, thus attesting to the quality of sealing. HE disassembly becomes much easier as flange disconnection does not require disassembly of complex adapters. Consequently, it improves performance, weight and dimensions, stock utilization ratio and operation of the system An expert in this field can also see other important advantages of this innovative approach.

Turning back to Fig. 3 (also seen on Fig. 5), one can note that flange 303 has a preferred frame-like shape with the width corresponding to the width of relevant furrows 202; seal 304 is also applied to said frame. When HE is assembled, flange 303 is installed in furrows 202 after HE plates 101 and 102 are compressed so tiiat seal 304 of the flange and the end seal (at the end of plates 101 and 102) described above and formed by compressing and squeezing out seal 301 come in contact and create solid sealing. Flange 303 can be attached to HE body, e. g. by stretching bolts. HE assembly and operation for the preferred embodiment is best shown on Fig. 5. First of all, seal 301 is applied to plates 101 and 102 in the manner described above (see Fig. 4). Plates 101 and 102 are then alternately placed into the set and installed between two body members 501. The upper and lower body members (top, bottom, front and rear are conditionally designated in accordance with Fig. 5) have two attaching points for flanges 303 at the front and at the rear and one attaching point on either side. After the set of plates 101 and 102 is installed between the body members, pins 507 with ties 506 (e. g. nuts) are inserted into aforesaid openings 201. When ties 506 are tightened, plates 101 and 102 are compressed. As they are compressed and since bulges 103 and 104 on plates 101 and 102 have a height that is less than the width of seal 301, the seal is compressed. Therefore, seal 301 fills all irregularities and furrows ensuring high-quality sealing of connections for adjacent plates 101 and 102. Due to compression, seal 301 is partially squeezed out into grooves 302 made along the edge of plates 101 and 102, and the squeezed-out part comes in contact with the adjacent plates. As a result, seal 301 forms vertically oriented, continuous sealing in grooves 302 at the ends of plates 101 and 102. Flanges 303 having seal 304 on their reverse side (see Fig. 3) are installed in furrows 202. Seal 304 of flanges 303 comes in contact with the vertically oriented end seal formed in grooves 302 thus creating a sealed interface between the flange and the remaining HE components. Moreover, the alternating pattern of applying seal 301 to plates 101 and 102 (see Fig. 3) leaves channels 504 and 505 open on the lateral HE sides while channels 502 and 503 remain open on the front and rear HE sides. Thus, hot and cold air flows are separated in HE.

At the same time, as indicated above, low pressure air (e. g. from the ACRS refrigerator) travels along channels 502-503 in HE without turns, with minimum pressure loss. Air from the compressor 504-505 makes a turn. A turn of high pressure flow in HE, as stated above, results in lower pressure loss compared to an identical turn for low pressure flow; in fact, this turn ensures additional improvement of HE performance.

It is important to note that in one of the embodiments hot air from the compressor is pre- separated into two flows and enters HE from two sides (see Fig. 6). This solution shrinks areas of cross-current at HE edges resulting in improved performance. While the area of plates 101 and 102 remains the same, its usage becomes much more efficient.

As indicated above, there are alternative flow direction patterns inside HE.

They can be arbitrarily divided into the following subgroups:

1) . Patterns wherein inlets and outlets of different flows are disposed on different pairs of opposing plate sides.

2) . Patterns wherein inlets and outlets of different flows are disposed on a single pair of opposing plate sides.

3) . Combinations of the above.

The above options only differ by the position of bulges on sheets with the resulting formation of channels and by the seal application pattems. Another difference of the above options is the position of flanges 303 and, consequently, the difference in the positions of grooves 302 that form the end seals and of furrows 202 that form areas of flange mounting. However, an expert would clearly see a capability to simultaneously produce multiple options as bulging and sealing tapes are universal and changing the positions for grooves 302 and furrows 202 is obviously a trivial and straightforward task for an expert based on prior art. The actual area of furrows 202 is an ultra-low value relative to the area of plates (101, 102); therefore, changing the number of furrows 202 and/or the position thereof will have no impact on achieving one of the advantages of the claimed HE, i. e. reduced material consumption and increased utilization ratio.

Thus, all embodiments as described below are manufactured, in technical and production terms, based on the preferred embodiment.

Various embodiments listed below can be used for different HE applications, depending on the specifications of a specific ACRS.

The first group includes, among others, the preferred embodiment of the claimed invention as described above. As indicated above, the air flow directions pattern in the preferred embodiment is shown on Fig. 6.

Another flow directions pattern is demonstrated on Fig. 7. In this case, inlet 502 and outlet 503 for the first flow are disposed on a single pair of opposing plate sides while inlet 504 and outlet 505 for the second flow are positioned on another pair of opposing plate sides. This pattern differs from the preferred embodiment in that inlet 504 for the second flow is disposed on one side of the pair of opposing sides while outlet 505 is positioned on the other side, and outlet 505 is shifted relative to inlet 504 towards the opposing end of the plate.

Embodiments from the second group are demonstrated on Fig. 8 and Fig. 9.

Fig. 8 shows a plate wherein the following is disposed: inlet and outlet (502, 505) for both flows on one side, and the respective inlet and outlet (503,504) for both flows on the other side. Both flows travel through HE without turns.

The embodiment shown on Fig. 9 differs from the embodiment shown on Fig. 8 in that one of the flows has two inlet openings (502) and two outlet openings (503) while the inlet for the second flow (504) is disposed between the outlet openings for the first flow (503) and, the outlet for the second flow (505) is disposed between two inlet openings for the first flow (502).

Embodiments from the third group are demonstrated on Fig. 10 and Fig. 1 1.

They represent modifications of the first group embodiments (Fig. 6, Fig. 7) wherein the channel for the first flow (inlet 502 and outlet 503) is divided into two sub channels that have an additional channel for the second flow between them in a counter-flow arrangement (inlet 504 and outlet 505).

Even though the above description relates mostly to the separation of gas flows, namely air, and to the operation as a component of ACRS, an expert in this field can clearly see other applications of the claimed HE.