FR2816043A1 - Heat exchanger or chemical reactor has series of levels, one above other, over which fluid flows, always in same direction, each level being connected to one below by ramp which connects its outlet end with inlet end of lower level - Google Patents

Abstract

The heat exchanger or chemical reactor has a series of levels (15), one above the other, over which a fluid flows, always in the same direction. Each level is connected to the one below by a ramp (22) which connects its outlet end with the inlet end of the lower level. An Independent claim is included for an exchange process carried out in a heat exchanger or chemical reactor as described above.

Description

<Desc / Clms Page number 1>

 The present invention relates to the technical means used to improve the circulation of a heat or material exchange fluid in an enclosure inside which an element is deposited vis-à-vis which the exchange must take place .

 The technical field concerned therefore includes exchangers of the type with a single fluid, as well as those used to establish an exchange between two different fluids, at least one of which is advantageously liquid and which must imperatively circulate in independent and sealed circuits.

 In this latter application, in particular, the proposed devices must, most often, meet the requirements of geometric space constraints.

In order to maintain the characteristics of the fluid which circulates in a device of reduced size, pass change devices (baffles) are installed to allow the fluid to traverse the number of round trips corresponding to the circulation in an unconstrained device. .

 Such a fluid circulates in the space which is delimited between the envelope of the apparatus and the internal element that this envelope surrounds that the internal element is constituted indifferently by an independent body which it is advisable to cool or to heat or by an exchange body, for example of the plate type, structurally speaking, an integral part of the device and which is traversed by a second fluid, in particular liquid. In such a case, the pass change system is located in the free space between the envelope and the internal element and comprises baffles which induce the change of circulation pass but which have the consequence of giving rise to zones of stagnation responsible for disadvantages, such as corrosion, fouling, differential expansion.

 There is therefore a need to be able to control the circulation of the fluid in the interval between the envelope and the internal element, at the same time as the reversal of circulation of the fluid in the change of pass.

 It is precisely the object of the invention to propose a new structure of exchangers which makes it possible to achieve these results while making it possible to meet the needs of change of pass in the apparatus and of circulation between the envelope and internal element.

<Desc / Clms Page number 2>

'la sortie de chaque intervalle avec l'entrée du suivant, 'et la sortie du dernier intervalle à une tubulure d'évacuation dudit fluide. According to the invention, the heat or material exchange process, within an exchanger or a chemical reactor comprising an element to be cooled, reheated or regulated in temperature and incorporated into an envelope or calender defining, with the element an exchange circuit borrowed by a fluid, is characterized - in that the element is organized within the grille so as to delimit separate stages defining intervals all reserving the same direction of circulation between an entry and an outlet that each has, - and in that said fluid is circulated by connecting:. the entry of the first interval to an intake manifold for said fluid,

'the exit from each interval with the entry of the next,' and the exit from the last interval to a discharge pipe for said fluid.

 The subject of the invention is also an exchanger or a chemical reactor, the structure of which is characterized in that: - the element delimits intervals having inlets and outlets and all allowing circulation of the fluid in the same direction, - the first interval is connected by its inlet directly to a fluid intake manifold, - the last interval is connected by its outlet directly to a fluid intake manifold - and the stages are joined to the grille by baffles connecting the exit of each interval, except that of the last one, with the entry of the next one.

 Various other characteristics will emerge from the description given below with reference to the appended drawings which show, by way of nonlimiting examples, embodiments and implementation of the subject of the invention.

<Desc / Clms Page number 3>

 Fig. 1 is a sectional elevation, partially cut away, of an exchanger according to the invention.

 Fig. 2 is a cross section taken along line n-n of FIG. 1.

 Fig. 3 is a section taken along the line m-m of FIG. 1.

 Fig. 4 is a partially broken away partial perspective showing in more detail a constructive characteristic of the exchanger.

 Fig. 5 is a partial perspective showing a constructive characteristic of the exchanger.

 Fig. 1 shows, by way of example, an exchanger, in particular of heat, according to the invention. Such an exchanger, designated as a whole by the reference 1, comprises a first element 2 which may consist of a finished product which should be subjected to cooling or heating or else by an exchange body constituted by a beam defining successive intercommunicating chambers.

 In an example of application, the bundle is advantageously formed of a plurality of double plates which are organized to delimit successive chambers 3, 31, ...... 3n Each chamber 3 is formed by the association of two plates 4 and 5 preformed and assembled perimeter tightly. The different chambers, arranged in parallel, are in communication with each other by connection pipes 6 and 7.

 In the example, the bundle is moreover connected, by one of the end chambers, such as chamber 3, to two pipes 8 and 9, respectively for inlet and outlet of a first fluid, preferably liquid, for which the exchange body 2 constitutes a first circulation circuit.

 The element 2 is incorporated in an envelope or calender 10 with which it delimits an exchange body 11. The calender 10 can be produced in several suitable ways and, for example, in the form of a ferrule which is connected to two pipes 12 and 13, respectively, for admission and discharge of a fluid responsible for ensuring a heat exchange with the element 2 and in this case with the element 2 with the fluid passing through or circulating inside body 2.

<Desc / Clms Page number 4>

 In the application example, provision is made to organize the bundle 2 in such a way that the pairs of plates 4 and 5 are organized in separate stages delimiting between them each time an interval 15 having an open section called the inlet 16 and an open section called exit 17. The organization in separate stages is also provided in such a way that the intervals 15 extend parallel to each other and that the open sections 16 and 17 are placed in the same way to establish a possible circulation in each interval in the same direction shown by the arrow fi.

 According to another constructive arrangement, the first interval 15, corresponding to that which can be appreciated as being in relation to the intake manifold 12, is connected by its outlet section with the inlet section of the following interval which is the subject of the same connection with the following interval, the same arrangement being retained until the last interval 15, the open outlet section 17 of which is in connection with the pipe 13. This organization defines a circuit circulation in baffles or zigzag to the last interval 15 by forcing the second fluid to pass through each interval in the same direction.

 To achieve such a result, according to the structure of the invention, the successive intervals 15 are delimited between the inlet and outlet sections 16 and 17 by walls 20 extending between the successive stages and being located at a distance from the internal periphery of the grille 10.

 In this way, as shown in Figs. 2 to 4, the walls 20 delimit, inside the grille, one or more lateral corridors 21 which are occupied by inclined partitions 22 connecting a chamber 3, at the level of the outlet section of the corresponding interval 15 to the next room 3, but at the level of the entry section of the interval that this room delimits with the previous one.

 The partitions 22 constitute baffles linked or joined in a sealed manner to the peripheral wall of the grille 10 to the walls 20 as well as to the edges of each chamber 3.

 As shown in fig. 1, the second fluid borrows the tubing 12 in the direction of the arrow f2 to cross the first interval 15 and be led towards the open outlet section 17 to the right of which it is deflected by the calender into two sub-veins oriented towards the lateral corridors 21 which lead these sub-veins to the

<Desc / Clms Page number 5>

 right of the entry section of the next interval 15 in which it is reconstituted in the form of the initial elementary vein.

 The fluid continues to circulate in the same way for all successive stages up to the last interval 15, the open outlet section 17 of which establishes direct communication with the discharge pipe 13.

 As shown in fig. 1, the obligation to traverse each interval in the same direction with, between two intervals, the division of the elementary vein into two sub veins inflected and circulating against the current allows the establishment of a homogeneous circulation inside the second exchange body 11 and promoting the reduction if not the elimination of the zones of least circulation which are detrimental to an optimal exchange ratio between the second fluid circulating in the exchange body 11 and the first fluid passing through the body exchange 2 through the different successive chambers 3, 31, .... 3n.

 Figs. 1 to 4 show an exemplary embodiment involving a ferrule or grille 10 of cylindrical shape and the presence of walls 20 in the form of a sector of cylindrical walls.

 Fig. 5 shows that it is possible to adopt a different architecture by using plates 4 and 5 of rectangular shape, suitably tightly linked to define the successive stages or chambers 3 and associated with planar walls 20 so that the first exchange body 2 thus formed can be inserted inside a grille offering a complementary polygonal section.

 It should be considered that the representation given by fig. 1 is given by way of example as regards the orientation given to the exchanger. Indeed, according to the invention, it does not matter whether the circulation of the first fluid along the arrow f is established horizontally or vertically. Similarly, in an orientation of the type of FIG. 1, it is possible to make the fluid penetrate into the calender 10 through the low pipe 13 and ensure its exit through the high pipe 12.

 It should be understood, within the meaning of the invention, that the exchanger 1 could be a chemical reactor.

 The invention is not limited to the examples described and shown since various modifications can be made thereto without departing from its scope.

Claims (6)

1-Exchange process within a chemical exchanger or reactor comprising an element to be cooled, heated or regulated in temperature or be the seat of a chemical reaction and incorporated into an envelope or calender defining, with the element, an exchange circuit borrowed by a fluid, characterized: - in that the element is organized within the grille so as to delimit separate stages defining intervals all reserving the same direction of circulation between an inlet and an outlet that each has, - and in that one circulates said fluid by connecting:. the entry of the first interval to an intake manifold for said fluid,. the exit from each interval with the entry of the next, and the exit from the last interval to a discharge pipe for said fluid.  2-A method according to claim 1, characterized in that the fluid is circulated in the form of a vein in each interval and in that this vein is subdivided into two lateral sub-veins, between the outlet of each interval and the inlet of the next, except for the last interval, the outlet of which is connected directly to the discharge pipe of said second fluid.  3-Heat exchanger or chemical reactor comprising an element to be cooled or reheated, incorporated into a calender (1) to define with the latter intervals (15) delimiting a circulation circuit for an exchange fluid, characterized in that: - the element delimits intervals (15) having inlets (16) and outlets (17) and all allowing circulation of the fluid in the same direction, - the first interval (15) is connected by its inlet directly to a pipe (12) fluid intake, <Desc / Clms Page number 7>  - The last interval (15) is connected by its output directly to a tube (13) for evacuating said fluid - and the stages are joined to the grille by baffles (22) relating the output of each interval, except that of the last, with the entry of the next.  4-Exchanger or chemical reactor according to claim 3, characterized in that the intervals (15) are delimited between the inputs and the outputs by walls (20) connecting the stages and being located at a distance from the grille (10) to define at least one corridor (21) occupied by a partition (22).  5-Exchanger or chemical reactor according to claim 4, characterized in that the walls (20) define between the calender and the element two lateral passageways (21).  6-exchanger or chemical reactor according to claim 4, characterized in that the baffles are formed for each stage, apart from the last, by at least one partition (22) which is connected: e to the part of the stages, defining the outlet ( 17) of an interval (15), * to the part of the floors defining the entry (16) of the following interval (15),

 * to the wall (20) connecting two successive stages, * and to the grille (10).