FR3033879A1 - BLOCK HEAT EXCHANGER, ITS IMPLEMENTATION METHOD AND THERMAL EXCHANGE BLOCK BELONGING TO SUCH AN EXCHANGER - Google Patents

Abstract

This exchanger comprises an enclosure having a bottom (5), a cover (4) and a peripheral envelope (6), at least one block (1 - 3) disposed between the bottom and the cover, each block comprising a body, channels (10) longitudinal and transverse channels (12). At least one interface among the interfaces (112, 114, 123, 135) between two facing faces belonging to the cover and to the block adjacent thereto, to the bottom and to the adjacent block, possibly to two contiguous blocks, a radially inner circumferential seal (J1, J'1) is provided, which extends radially out of the region (14) of outlets of the longitudinal channels, and a radially outer peripheral seal (J2, J 2) defining, with the inner peripheral seal and the opposite end faces, an annular space (E, E ') for confining a possible leak of one or the other fluid. This confers improved sealing, in particular by comparison with solutions involving a single seal between these two streams. The effectiveness of each joint is improved, while its life is increased. Finally the operator can be warned, substantially immediately, in case of malfunction of one of the seals.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to the technical field of block heat exchangers. BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to the technical field of block heat exchangers. It relates more particularly to such a block heat exchanger, which is equipped with means for identifying a possible leak of one of the fluids circulating in this exchanger.

STATE OF THE ART There are many types of heat exchangers, among which there will be mentioned, inter alia, plate, tube or finned exchangers. The invention is more particularly directed to a block-type heat exchanger comprising an enclosure in which at least one heat exchange block is housed. Usually, this chamber receives several of these blocks, which are stacked on top of each other. Each block is made of a thermally conductive material, such as graphite possibly combined with additives, for example of the polymer type. This block, which may be parallelepipedal or cylindrical, is hollowed out of two series of channels extending perpendicularly to each other. These channels are intended for the circulation of two fluids, in order to put them in exchange for mutual heat. Typically, the first fluid is for example an acid, while the second fluid is a coolant, especially water. There are two main constructive modes, for the realization of the heat exchange blocks above. In a first mode, the first channels are longitudinal and open on the front faces of the body, while the second channels are transverse and open on the opposite transverse faces of the body. In an alternative construction mode, both the first and second channels are longitudinal and open on the front faces of the body.

The facing faces, belonging to two contiguous stacked blocks, are in mutual support. Moreover, the end blocks are respectively placed against the bottom and the cover of this enclosure. The latter is finally equipped with different tubings, allowing the supply of fluids in the two series of channels, and their evacuation out of these channels. For example, block heat exchangers are known from EP-A-0 196 548 or from VVO-A-2006/081965. It is understood that the technical problem of sealing is of particular importance in this type of exchanger. Indeed, if there is a leak of one of the two fluids circulating in the channels, there is a risk of mixing between these fluids. This leakage induces at least an economic loss since the fluids put in contact with each other are no longer usable, or even a material and human risk if the mixing between the fluids is dangerous, especially if it is explosive.

Various solutions have already been proposed for monitoring the good sealing between fluids circulating in heat exchangers. The following documents are especially mentioned: VVO-A-2005/119197, DE-A-195 01 467 or DE-A-433 13 14. These different arrangements are however not applicable to block exchangers, at least immediate way. That being said, an object of the present invention is to provide a block heat exchanger which has improved sealing compared to exchangers of the same type, known from the state of the art.

Another object of the present invention is to provide such a heat exchanger, which allows effective monitoring of the seal between the two fluids circulating in the channels of this exchanger.

Another object of the present invention is to provide such a heat exchanger, which has a relatively simple structure and which can be manufactured without particular risk of mechanical failure, particularly with respect to channels dug in the blocks belonging to this exchanger.

OBJECT OF THE INVENTION An object of the present invention is a heat exchanger comprising - an enclosure having a bottom, a cover and a peripheral envelope, - at least one block disposed between the bottom and the cover, each block comprising a body, first longitudinal channels, formed in this body in a longitudinal direction of the block, which open on two opposite end faces of the body, the exchanger further comprising first inlet means of a first fluid in the first channels, second means for inputting a second fluid into the second channels, first means for outputting the first fluid out of the first channels, second means for outputting the second fluid out of the second channels, means for sealing between the first and second fluids, said exchanger being characterized in that the sealing means comprise, at least one interface among the interfaces between two end faces in view 3033879 3 belonging to the cover and to the block adjacent thereto, to the bottom and to the block which is adjacent thereto, possibly to two contiguous blocks, at least one radially inner peripheral seal, each inner seal extending radially outwardly the zone of outlets of at least a portion of the longitudinal channels, and a radially outer peripheral seal 5 defining, with the peripheral seal (s) and inner faces and opposite faces, a gap containment of a possible leak of one or the other fluid. According to other characteristics of the exchanger according to the invention: the second channels are transverse and there is provided a single radially inner seal extending radially outside the zone of the outlets of the longitudinal channels; containment space being ring-shaped; the second channels are also longitudinal and at least one radially inner seal is provided, each first inner seal extending outside the outlet area of at least a portion of the first longitudinal channels, and at least one second radially inner seal, each second inner seal extending outside the outlet area of at least a portion of the second longitudinal channels; the first and second longitudinal channels are arranged in a succession of alternating rows, the zone of outlets of each row being surrounded by a respective radially inner seal; the sealing means comprise said at least one inner peripheral seal and said outer peripheral seal, at all the interfaces between two contiguous blocks; The sealing means comprise said at least one inner peripheral seal and said outer peripheral seal, to all of said interfaces; the exchanger further comprises detection means suitable for detecting the presence of at least one of the first and second fluids, within at least one annular confinement space; The exchanger further comprises an alarm capable of being activated by the detection means; - The exchanger further comprises evacuation means adapted to evacuate outside the enclosure said leakage of any fluid, confined in at least one annular space; The evacuation means are placed in communication by the fluid with the detection means; The detection means are distant from the enclosure and there is provided a clean connecting pipe to connect these detection means and the outlet of the evacuation means; the evacuation means comprise at least one evacuation pipe, each evacuation pipe being formed in a respective block and connecting two adjacent confinement spaces; the evacuation means comprise an evacuation tunnel formed in the bottom and / or the cover, which tunnel connects a confinement space and the outside of the enclosure; The seal is an O-ring received in grooves formed respectively on the two faces facing each other. Another object of the present invention is a process for implementing an exchanger as above, in which the first and second fluids are circulated in the first and second channels, so as to put them in exchange for heat, and the circulation of at least one fluid is stopped if the presence of said fluid is detected in at least one annular confinement space. According to other characteristics of the process according to the invention: at least one inner seal is replaced if the presence of the first fluid is detected in at least one annular confinement space; the outer seal is replaced if the presence of the second fluid is detected in at least one annular confinement space.

Another object of the present invention is a heat exchange block comprising a body, said first longitudinal channels, formed in this body in a longitudinal direction of the block, which open on two opposite end faces of the body, said second channels. transverse, formed in this body in a transverse direction of the block, which open on two opposite transverse faces of the body, said block being characterized in that it further comprises, on each front face, at least one radially inner peripheral seat which extends radially outside the region of the outlets of the longitudinal channels, this seat being adapted to receive a first seal, a radially outer peripheral seat adapted to receive a second seal 35 sealing, this outer peripheral seat defining with the inner peripheral seat an annular intermediate section e and in that at least one evacuation pipe connects the opposite end faces and opens on the two opposite annular sections.

The invention achieves the previously mentioned objectives. A heat exchanger, of the type targeted by the invention, delimits a certain number of interfaces, between the end faces opposite its constituent elements. There is therefore a first interface between the cover and the block adjacent thereto, an opposite interface 5 between the bottom and the adjacent block, as well as any additional interfaces between each pair of contiguous blocks. The invention achieves the previously mentioned objectives. A heat exchanger, of the type targeted by the invention, delimits a number of interfaces, between the front faces opposite its constituent elements. There is therefore a first interface between the cover and the block adjacent thereto, an opposite interface between the bottom and the adjacent block, and any additional interfaces between each pair of contiguous blocks.

The invention relates to two main types of heat exchangers. According to a first constructive mode, only the first channels, intended for the circulation of a first fluid, called process fluid, are longitudinal and open on the front faces of each block. On the other hand, the second channels, intended for the circulation of the coolant, are transverse and open on the lateral faces of each block. In this case, the inner seal (s) surrounds only the outlet of the first channels at the end faces. It is typically provided with a single inner seal, forming an annular containment space with the outer seal. According to an alternative construction mode, both the first and second channels are longitudinal and open on the front faces of each block. In this case, there are provided at least two inner seals, one of which surrounds the outlet of the first channels and the other the outlet of the second channels. A greater number of inner seals may be provided depending on the arrangement of the different channels. In the typical case of a succession of alternating rows between the first and second channels, a number of internal seals, corresponding to the number of rows, are provided. The invention ensures the seal between the two fluids put in heat exchange, firstly thanks to the (x) seal (s) interior (s). In case of malfunction of this (s) internal seal (s), the possible leakage of fluid is confined because of the presence of the outer seal. This double degree of security is provided on at least one of the interfaces listed above, in particular on all the interfaces between each pair of contiguous blocks, preferably on all the interfaces listed above. This provides improved sealing and safety, particularly compared to solutions involving a single seal between these two streams. The invention also makes it possible to warn the operator in a substantially immediate manner, in the event of malfunction of one of the seals. Depending on the nature of the fluid, confined in the annular space and then discharged out of the exchanger, the operator knows which of the two seals is out of use. He can proceed to the detailed replacement of this faulty seal, before restarting the implementation of the installation.

It will be noted that the invention makes it possible to substantially overcome any risk of contact between the two fluids. Indeed, such contacting occurs only in the case, highly improbable in practice, where the two joints pass simultaneously from a functional state to a defective state. In the most common case, only one of these joints becomes out of use while the other remains operational. The operator is notified without delay, stops the flow of fluids and replaces the defective seal. Therefore, the exchanger of the invention is particularly suitable for the exchange of heat between two fluids with high criticality. For example, the case where one of the two fluids has a high purity, so that it does not accept any contamination, or the case where the mixture between these fluids can cause an explosion or a harmful gas emission. . Finally, the blocks belonging to the exchanger according to the invention have a small number of additional mechanical members, compared with the conventional blocks of the prior art. Moreover, these mechanical members are arranged at a distance from the fluid passage channels. Therefore, the manufacture of these blocks does not induce a significant increase in the risk of rupture. In addition, in use, these blocks have a robustness and a satisfactory life.

DESCRIPTION OF THE FIGURES The invention will be described hereinafter with reference to the accompanying drawings, given by way of non-limiting example, in which: FIG. 1 is a longitudinal sectional view illustrating a heat exchanger according to FIG. invention; Fig. 2 is a cut away perspective view illustrating a block belonging to the exchanger of Fig. 1; Figure 3 is a longitudinal sectional view, similar to Figure 1, illustrating in more detail a longitudinal end of the heat exchanger according to the invention; and Figs. 4 to 6 is a longitudinal sectional view on a much larger scale, illustrating the junction area between two blocks, respectively in a sealing configuration and in two leak configurations of one or the other of the two fluids circulating in this exchanger.

Figure 7 is a top view illustrating a heat exchange block belonging to a heat exchanger according to an alternative embodiment of the invention. FIGS. 8 and 9 are views from above, similar to FIG. 7, illustrating two configurations of leaks of one or the other of the two fluids flowing in the exchanger of this FIG.

Detailed Description of the Invention The following reference numerals are used in the figures: 1-3 Heat exchange blocks 6 Shell 4 Bottom 61 Cover 6 5 Cover 62 Chamber 6 112 Interface 1 to 2 63.64 Tubing of 6 114 Interface between 1 and 4 J 1, J2 Joints between 1 and 2 123 Interface between 2 and 3 11,12 Functional gaps 135 Interface between 3 and 5 J'1, J'2 Joints between 1 and 4 L Main axis of the exchanger E, E 'Containment spaces L1 Main axis bu block 1 80 Detection device 10 Longitudinal channels of 1 82 Alarm 11,11' Front faces of 1 201 Heat exchange block 12 Transverse channels of 1 210 1st channel 201 13,13 'Transverse faces of 1,211 End face of 1 14 Outlet area of 10,212 2nd channels of 201 15,15' Inner gorges of 10 R1-R3 Rows of channels 210 16,16 'External gorges of 10 R'1 , R'2 Rows 212 212 17,17 'Annular sections DR1-DR3 R1-R3 outlets area 18,28,38 DR'1-DR'2 ducts Zone outlets of R'1-R'2 41 Opening of 4 JR1-JR3 Joints of R1-R3 42 Plate of 4 JR'1-JR'2 Joints of R'1-R'2 43 Tunnel 217 Intermediate 44 Outlet of 43 218 Conduit 51 Opening of 5 E201 Containment space 15 As illustrated in particular in FIG. 1, the heat exchanger according to a first embodiment of the invention essentially comprises several heat exchange blocks 1 to 3, a bottom 4 , a cover 5, and a peripheral envelope 6. In the example there is shown three blocks stacked one above the other, it being understood that a different number of blocks can be provided. The interfaces between the end faces 20 facing these constituent elements are referenced, from top to bottom, 135, 123, 112 and 114.

In what follows, we will describe more particularly the structure of the block 1, it being understood that the blocks 2 and 3 have a similar structure. The mechanical elements of these blocks 2 and 3 similar to those of block 1 are assigned the same reference numbers, the prefix "1" being replaced respectively by "2" or "3". These different blocks 5 are made of any suitable material known from the state of the art, such as graphite. As shown in particular in Figure 2, the block 1 has a cylindrical shape of circular section. As a variant, it may be of different shape, in particular parallelepipedal, in particular cubic. We denote L1 its main or longitudinal axis, which is parallel to the main axis L of the exchanger. In a manner known per se, this block 1 is hollowed out with different channels, for the flow of two fluids intended to be put in mutual heat exchange.

First there is a first series of channels 10 parallel to the axis L1, said longitudinal channels, which open on the opposite end faces 11 and 11 'of the block. Furthermore a second series of transverse channels 12, extending obliquely, in particular perpendicular to the axis L1, open on the opposite transverse faces 13 and 13 'of the block. In operation, two fluids are circulated in heat exchange, circulating respectively in the first and second series of channels. These channels are distant from each other, namely that they do not open into each other. Dotted lines on the front face 11 illustrate the zone 14 known as the opening of the longitudinal channels. This zone 14, circular in shape, connects the outer edge of the peripheral longitudinal channels. A similar outlet area, not shown, is associated with the other end face 11 '. Each end face is hollowed by two concentric grooves, one of which 15 or 15 'is said radially inner and the other 16 or 16' radially outer. Each inner groove 15 and 15 'is formed outside the outlet area, namely that the inner edge of this groove is remote from the outlet of the peripheral channels. The grooves 15, 15 ', 16 and 16' are adapted to form the seat of a sealing member, for example of the O-ring type. In the example shown, they have a section in the form of a circular arc. Nevertheless, they can adopt any other profile, specific to the reception of the aforementioned sealing member. There are 17 and 17 'the two annular intermediate sections, defined by the edges facing the inner and outer grooves.

The block 1 is hollowed out of a duct 18, extending generally along the direction L1, which opens on the end faces 11 and 11 'by connecting the two intermediate sections 17 and 17'. It may be provided to provide several ducts, similar to that 18, preferably angularly distributed regularly. Without limitation, the section of each duct is between 0.1 and 50 mm (millimeters). In terms of manufacturing method, the channels 10 and 20 are dug in the usual way. The duct 18 is pierced according to a similar method, regardless of whether or not the ducts are made. Finally, the various grooves 15, 15 ', 16 and 16' are provided by any appropriate means, again indifferently before or after the production of the channels. Again with reference to FIG. 1, the bottom 4 is hollowed out with an opening 41 intended for the entry of a first fluid into the channels 10. This inlet is placed in communication with a source of this fluid, which is located upstream and is not illustrated. Similarly, the lid 5 is hollowed out with an opening 51 intended for the outlet of the first fluid out of the channels 10. This outlet is placed in communication with a recovery tank, which is located downstream and is not illustrated. The stack of blocks 1 to 3 is surrounded by means of an envelope 6 defining a receiving enclosure, with the bottom and the cover. Conventionally, this envelope has a flange 61, allowing its attachment to a plate 42, belonging to the bottom (see Figure 3). Similarly, it is provided with means for fixing it on the lid. This envelope delimits, with the walls opposite the blocks, a peripheral chamber 62 for the circulation of a second fluid, intended to be put in heat exchange with the first fluid in the blocks 1 to 3. For this purpose, the casing is equipped with respective inlet 63 and outlet 64 pipes of this second fluid, placed in communication with a source and a recovery tank. The various mechanical elements, listed in the last three paragraphs, are of a type known per se. Therefore, they will not be described in more detail in the following. Figure 4 illustrates the stack between blocks 1 and 2. Two O-rings J1 and J2 are received in the respective grooves 15 and 25 ', as well as 16 and 26'. The front faces 11 and 21 'of the blocks are arranged opposite, providing functional interstices 11 and 12, the thickness of which has been enlarged in the drawing for the sake of clarity. In addition, a spacer space E, said confinement, is provided between the facing walls belonging to sections 17 and 27 ', as well as joints J1 and J2. This space is annular, in that it extends over the entire periphery of the interface 112. The ducts 18 and 28, dug in the blocks 1 and 2, open into this space E. As illustrated in FIG. 3, the stack between the block 1 and the bottom 4 is similar to the stack described above between the two blocks 1 and 2. There are two O-rings J'1 and J'2 interposed between the end faces facing these block 1 and the bottom 4. These seals and these end faces define an annular confinement space E ', similar to that E above. The bottom 4 is further hollowed out by an evacuation tunnel 43, connecting the annular space E 'and the outside of the enclosure. The outlet of this tunnel is noted 44 on the outer front face of the cover. The walls of this outlet receive the first end of a pipe 70, of any suitable type, the other end cooperates with a detection member 80. The latter is able to transmit a signal to the operator via an alarm 82 when it detects the arrival of one or the other of the two fluids circulating in the various blocks 1 to 3. This signal may be of any suitable nature, in particular sound, visual or electronic. There is a similar stack, on the one hand between the other blocks 2 and 3 and, on the other hand, between the block 3 and the cover 5. At each interface respectively 123 and 135, two O-rings are interposed between the faces in view of these mechanical elements, 20 delimiting two other confinement spaces. In addition, the block 3 is dug a pipe similar to that 18 formed in the block 1. On the other hand, the lid is not equipped with a tunnel, such as the one 43 of the bottom. The implementation of the heat exchanger, described above, will now be explained in what follows.

The first heat exchanged fluid is admitted through the inlet opening 41, flows successively into the channels 10, 20 and 30, before being discharged through the outlet opening 51. The second fluid is admitted by the inlet pipe 63, flows in the channels 12, 22 and 32, before being discharged through the outlet pipe 64. These flows are indicated by arrows in dashed and mixed lines respectively, on the FIG. 4 more particularly illustrates the flow of fluids between blocks 1 and 2, it being understood that this flow is similar between the other blocks 2 and 3, between block 1 and the bottom, as well as between the block 3 and the lid. When these fluids infiltrate into the respective interstices 11 and 12, they come into contact with the J1 and J2 joints. In normal operation illustrated in this FIG. 4, the joints J1 and J2 are functional so that they prevent the passage of fluids towards the annular space and that there is no mixing between these fluids. No fluid flows in the pipe 70, shown schematically in this FIG. 4, while the detector 80 and the alarm 82 are inactive, so that they are represented by dashed lines. However, it is now assumed that the inner seal J1 is defective, which is illustrated in Figure 5. There is therefore a leakage of the first fluid from the gap 11 in the direction of the safety space E. On note that this first fluid can not be brought into contact with the second fluid present in the gap 12, due to the presence of J2 seal which remains functional. This first fluid is then directed along the conduit 18, then the tunnel 43.

The first fluid is then discharged from the enclosure, via the pipe 70, towards the detection member 80. The latter then activates the alarm 82, which indicates to the operator that he must stop the walk of the installation. The operator is further informed of the nature of the fluid thus evacuated, so that it can proceed to a detailed replacement of the first seal J1.

If it is now assumed that the outer seal J2 is defective, as shown in Figure 6, there is a leakage of the second fluid from the gap 12 towards the safety space E. It will be noted that this second fluid can not be brought into contact with the first fluid present in the gap 11, because of the presence of J1 seal which remains functional.

This second fluid is then directed via the conduit 18, the tunnel 43 and the pipe 70, to the detection member. As in the previous case, the operator is alerted to the malfunction, so that it stops the implementation of the installation and proceeds to replace this second seal J2. If the leakage of one or the other fluid occurs at the interface between the upper block 3 and the cover 5, the fluid is evacuated successively along the lines 38, 28 and 18, before being evacuated via the tunnel 43. If this leak occurs at the interface between the two blocks 2 and 3, the fluid is sucked successively along the lines 28 and 18, before being discharged via the tunnel 43. Finally if this leakage occurs at the interface between the lower block 1 and the bottom 4, the fluid is directly discharged via the tunnel 43.

The lines 18, 28 and 38, as well as the tunnel 43, form evacuation means, making it possible to direct any leakage of fluid outside the enclosure. These pipes and this tunnel do not open into the fluid passage channels, whether those oriented longitudinally or those oriented transversely.

FIG. 7 illustrates a heat exchange block 201 belonging to a heat exchanger according to an alternative embodiment of the invention. In this figure the mechanical elements similar to those of the preceding figures are assigned the same reference numbers, increased by 200.

The block 201 of FIG. 7 differs from that of FIGS. 1 to 6, first of all in that it is rectangular in shape, but also in that the two series of channels are parallel and open on the end faces. each block, of which only one 211 is referenced in this figure. There is therefore first of all the first series of channels 210, similar to those 10 of the previous figures. The second series is also formed of longitudinal channels 212, as opposed to the transverse channels 12 of the preceding figures. These different channels 210 and 212 are substantially parallel, namely that they do not open into each other. As in the embodiment of the preceding figures, two fluids are circulated in heat exchange, circulating respectively in the first and second series of channels. These two fluids are of the same nature as those described above. More specifically, the channels are formed by parallel rows, arranged alternately in plan view. Three rows R1 to R3 of first channels 210 are thus found, as well as two rows R'1 and R'2 of second channels 212. FIG. 7 shows in dashed lines the various areas of outlet of the longitudinal channels. either DR1 to DR3 for the rows of the first series and DR'1, DR'2 for the rows of the second series. Each zone, of rectangular shape, extends around the perimeter of a respective row of channels. The front face 211 is hollowed out with rectangular grooves, called inner grooves, each of which extends outside a corresponding outlet area. The different internal grooves receive respective sealing members, JR1 to JR3, and JR'1 and JR'2, which are for example similar to that J1 of the first embodiment. This front face 211 is further hollowed out with a peripheral rectangular groove, said outer, which surrounds the various internal grooves mentioned above. This outer groove 25 receives a sealing member JP, which is for example similar to that J2 of the first embodiment. Note 217 the intermediate section, defined by the edges facing the inner and outer grooves explained above. An intermediate section, not shown, is similarly defined on the other end face of the block 201. This block is furthermore hollowed out by several ducts 218, generally parallel to the channels 210 and 212, which open on the front faces by connecting the two intermediate sections defined above. In the illustrated example, four of these ducts are provided, placed in the vicinity of the corners of the block, it being understood that a different number of ducts and / or a different arrangement of these ducts may be envisaged.

When the block 201 is stacked on a similar block not shown, these contiguous blocks define a confinement space E201, similar to that E of the previous figures. This space is delimited by the facing faces belonging to the section 217 and to the unrepresented section of the contiguous block, as well as by the joints JP, JR1 to JR3, as well as JR'1 and 3033879 13 JR'2. As in the first embodiment, other confinement spaces are advantageously formed by the facing walls of the other contiguous blocks, by the facing walls of the bottom and of the block which is contiguous thereto, as well as by the walls opposite the cover and block adjoining it.

In normal operation illustrated in FIG. 7, the inner seals are functional, so that they prevent the passage of fluids towards the confinement space and that there is no mixing between these fluids. If it is assumed that one of the joints JR1 to J R3, for example that JR1 is defective, there is therefore a leakage of the first fluid to the safety space E201. It should be noted that this first fluid can not be brought into contact with the second fluid, because of the presence of JR'1 and JR'2 joints which remain functional. This first fluid is then directed along the ducts 218, according to the dashed lines illustrated in FIG. 8. It then flows into a not shown tunnel similar to that 43, before being evacuated out of the enclosure, as in FIG. the first embodiment.

If it is now assumed that one of the JR'1 or JR'2 joints, for example that JR'1 is defective, there is a leakage of the second fluid towards the E201 safety space. It will be noted that this second fluid can not be brought into contact with the first fluid because of the presence of the JR1 to JR3 seals which remain functional. This second fluid is then directed along the ducts 218, in the mixed lines illustrated in Figure 9. It then flows into the unrepresented tunnel mentioned in the previous paragraph, before being evacuated outside the enclosure. The invention is not limited to the example described and shown. In particular, O-rings have been illustrated as sealing members respectively inside and outside.

Nevertheless, it may be provided to replace these O-rings by any other suitable seal, for example a multiple seal.

Claims (18)

CLAIMS1, heat exchanger comprising an enclosure having a bottom (5), a cover (4) and a peripheral casing (6), at least one block (1 - 3; 201) disposed between the bottom and the cover, each block comprising a body, longitudinal first channels (10; 210) formed in this body in a longitudinal direction (L1) of the block, which open on two opposite end faces (11, 11 '; 211) of the body of the second channels (12); 212), formed in this body in a second direction, which is: * is a transverse direction, these second channels then being transverse channels, which open on two transverse faces (13, 13 ') opposite the body, * is said longitudinal direction, these second channels then being longitudinal channels (212) also opening on said opposite end faces (211) of the body, the exchanger further comprising first means (41) for entering a first fluid into the first canau x - second means (63) for inputting a second fluid into the second channels of the first means (51) for outputting the first fluid out of the first channels of the second means (64) for outputting the second fluid out of the second channels sealing means between the first and second fluids, said exchanger being characterized in that the sealing means comprise at least one of the interfaces (112, 114, 123, 135) between two facing faces. belonging to: the lid and the block which is adjacent to the bottom and the block which is adjacent thereto possibly to two contiguous blocks at least one radially inner peripheral seal (J1, J'1; JR1, JR11, JR2, JR12, JR3), each inner seal extending radially out of the area (14; DR1, DR11, DR2, DR'2, DR3) outlets of at least a portion of the channels longitudinal, a radially outer peripheral seal (J2, J'2) defining, with the peripheral seal (s) 35 (s) and the facing end faces, a space (E, E '; E201 ) containment of a possible leak of one or the other fluid. 3033879 15 2. Heat exchanger according to claim 1, characterized in that the second channels (12) are transverse and there is provided a single radially inner seal (J1, J'1) extending radially outside the zone (14). ) outlets of the longitudinal channels, the confinement space (E, E ') being ring-shaped. 3. Heat exchanger according to claim 1, characterized in that the second channels (212) are also longitudinal and there is provided at least one first radially inner seal (JR1, JR2, JR3), each first inner seal extending to outside the zone (DR1, DR2, DR3) outlets of at least a portion of the first longitudinal channels, and at least one second radially inner seal (JR'1, JR'2), each second inner seal s extending out of the zone (DR'l, DR'2) outlets of at least a portion of the second longitudinal channels. 4. Heat exchanger according to claim 3, characterized in that the first (210) and second (212) longitudinal channels are arranged in a succession of alternating rows (R1, R'1, R2, R'2, R3), the zone (DR1, DR'1, DR2, DR'2, DR3) outlets of each row being surrounded by a respective radially inner seal (JR1, JR'1, JR2, JR'2, JR3). 5. Heat exchanger according to one of the preceding claims, characterized in that it comprises at least two blocks (1-3) stacked on each other in a longitudinal direction (L) of the exchanger, between the bottom ( 4) and the cover (5). 6. Heat exchanger according to the preceding claim, characterized in that the sealing means comprise said at least one inner peripheral seal (J1) and said outer peripheral seal (J2) at all interfaces (112, 123) between two contiguous blocks. 7. Heat exchanger according to one of the preceding claims, characterized in that the sealing means comprise said at least one inner peripheral seal (J1, J'1) and said outer peripheral seal (J2, J'2), to all of said interfaces (112, 114, 123, 135). 8. Heat exchanger according to one of the preceding claims, characterized in that it further comprises detection means (80) for detecting the presence of at least one of the first and the second fluid, interior of at least one annular confinement space (E, E '). 3033879 16 9. Heat exchanger according to the preceding claim, characterized in that it further comprises an alarm (82), adapted to be activated by the detection means (80). 5 10. Heat exchanger according to one of the preceding claims, characterized in that it further comprises discharge means (18, 28, 38, 43) adapted to evacuate outside the enclosure (4, 5, 6) said leakage of one or the other fluid, confined in at least one annular space. 10 11. Heat exchanger according to one of claims 8 or 9, taken in combination with claim 10, characterized in that the evacuation means (18, 28, 38, 43) are placed in communication by the fluid with the means detection (80). 12. Heat exchanger according to claim 11, characterized in that the detecting means (80) are distant from the enclosure (4, 5, 6) and there is provided a connecting pipe (70) suitable for connecting these detection means and the outlet (44) of the evacuation means. 13. Heat exchanger according to one of claims 10 to 12, characterized in that the evacuation means comprise at least one discharge pipe (18, 28, 38), each discharge pipe being formed in a block respective and connecting two adjacent confinement spaces (E, E '). 14. Heat exchanger according to one of claims 10 to 13, characterized in that the evacuation means comprise an evacuation tunnel (43) formed in the bottom (4) and / or the cover, which tunnel connects a confinement space (E) and the outside of the enclosure. 15. A method of implementing an exchanger according to one of claims 8 to 14, wherein the first and second fluids are circulated in the first and second channels, so as to put them in exchange for heat, and the circulation of at least one fluid is stopped if the presence of said fluid is detected in at least one annular confinement space. 35 16. The method as claimed in the preceding claim, wherein at least one inner seal is replaced if the presence of the first fluid is detected in at least one annular confinement space. 3033879 17 17. The method of claim 15 or 16, wherein the outer seal is replaced if the presence of the second fluid is detected in at least one annular confinement space. 5 18. Heat exchange block (1; 201) comprising a body, said longitudinal first channels (10; 210) formed in said body in a longitudinal direction (L1) of the block, which open on two end faces (11, II '; 211) opposite the body, 10 second channels (12; 212), formed in this body in a second direction, which is: * is a transverse direction, these second channels then being transverse channels, which lead to two opposite transverse faces (13, 13 ') of the body, * is said longitudinal direction, these second channels then being longitudinal channels (212) opening on said opposite end faces (211) of the body, said block being characterized in that it further comprises, on each front face, at least one radially inner peripheral seat (15, 15 '), each inner seat extending radially outside the outlet area of at least part of the longitudinal channels , the OR each inner seat being adapted to receive a respective inner seal 20, a so-called radially outer peripheral seat (16, 16 ') adapted to receive an outer seal, said outer peripheral seat defining with the inner peripheral seat an intermediate section (17, 17 '; 217), and in that at least one evacuation pipe (18) connects the opposite end faces and emerges on two opposite sections (17, 17 ').