JP2008520410A - Evaporation heat exchanger plant - Google Patents

Abstract

The distillation heat exchanger plant has at least two mutually parallel process lines (1) with at least two successive heat exchanger stages (2a, 2b), each heat exchanger stage being for condensation A plate package of a heat exchange plate in which a first inter-plate space and a second inter-plate space for evaporation are formed. The heat exchanger stages form a row (8) of heat exchanger stages provided adjacent to each other in a direction transverse to the process line. Each heat exchanger stage is configured so that vapor is supplied to the first inter-plate space of the first heat exchanger stage and liquid is supplied to the second inter-plate space to condense the vapor and evaporate the liquid. Has been. The supplied vapor condenses into a liquid, the supplied liquid evaporates, and the next stage heat exchanger stage is used to evaporate the liquid supplied to the second inter-plate space of the next stage heat exchanger stage. To the first inter-plate space. The plant has a closed casing (10) surrounding an inner space (11) in which a process line is provided. The casing is rectangular when viewed in cross section across the process line.

Description

  The present invention relates generally to a heat exchanger plant for distillation. The invention particularly relates to a heat exchanger plant for seawater desalination. More specifically, the present invention has at least one process line with at least two successive heat exchanger stages, each heat exchanger stage having a plate package of heat exchange plates, and heat exchange plates Is provided such that a first inter-plate space for condensation and a second inter-plate space for evaporation are formed in the plate package, and each heat exchanger stage is a first heat exchanger stage. Steam is supplied to the first inter-plate space and liquid is supplied to the second inter-plate space, the supplied steam condenses into the liquid, the supplied liquid evaporates, and the second heat exchanger stage In order to evaporate the liquid supplied to the space between the two plates, the liquid is supplied to the first inter-plate space of the next heat exchanger stage to condense the vapor and evaporate the liquid. Exchanger Process line having a stage is on Evaporative heat exchanger plant with a closed casing surrounding the inner space provided inside.

  For many years, the applicant has manufactured seawater desalination equipment in which packages with heat exchange plates form the main component of the process. The plate does not have a port for steam, the plate package is placed in a container, and the outer space of the plate is used as one or several flow paths for steam depending on the type of process. A large plant uses a cylindrical pressure vessel, and plate packages are arranged along the longitudinal direction of the cylinder. Large plants often have as many as five or six plate packages.

  The process takes place in several so-called effect parts, all of which are below atmospheric pressure. Vapor from the first effect part having the highest pressure and temperature flows into the second effect part and condenses in the inter-plate space for condensation. The salt water in the intermediate space for evaporation is evaporated by the radiated heat, and the generated steam flows into the next effect part. This process is repeated for other effect parts, and finally condensation takes place in a condenser where the refrigerant is water. Each effect part is provided with at least one plate package. However, the plate package should not have more than 1000-1200 plates, and if more plates are needed, two parallel plate packages are included in each effect portion.

  If more capacity is needed, a plant with several cylindrical containers is built. Providing three mutually parallel plate packages in one cylinder is not economical. The diameter must be adapted to three plate packages arranged adjacent to each other, increasing the diameter by about 50% compared to one container for three plate packages. This means that the thickness of the material is increased by 50% and the increase in the total amount of material exceeds 100%. A significant increase in cross-sectional area is advantageous because it results in a decrease in vapor velocity, but the economic effect is negligible. Therefore, individual costs cannot be reduced based on reliable valuation.

  U.S. Pat. No. 4,511,436 discloses a seawater desalination plant. The plant has a process line with several consecutive heat exchanger stages, each heat exchanger stage having a plate package of heat exchange plates. The plate packages are welded to each other in pairs, and a first gap space for condensation and a second inter-plate space for evaporation are formed in the plate package. The process line of the heat exchange plate extends vertically and the first stage is located at the top. Parallel to the vertically extending process line, a vertically extending heat exchanger line is provided for preheating seawater to be desalinated. These two lines are provided in a closed pressure vessel and are shown schematically in this document. The casing construction is mentioned in U.S. Pat. No. 4,511,436 and is shown in the corresponding application published as U.S. Pat. No. 4,514,260.

  This document, U.S. Pat. No. 4,514,260, discloses a similar plant with multiple plate packages stacked on top of each other and stacked vertically to a height substantially greater than the width and length of the horizontal plane. ing. The plate package is surrounded by a casing. The casing includes two flat side portions extending in the vertical direction and facing each other, and two side portions extending in the vertical direction and facing each other and curved outward.

  The object of the present invention is to provide a heat exchanger plant which has a very large capacity and can be manufactured and installed in a cost-effective manner. It is a further object of the present invention to provide a heat exchanger plant having a structure that can be increased in capacity and that can include multiple heat exchanger stages.

  The purpose of this is a heat exchanger plant as described above, having at least two process lines with continuous heat exchange stages, the at least two process lines running parallel to each other in the inner space, The stage forms, in the inner space of the casing, a row of heat exchanger stages provided adjacent to each other in a direction transverse to the process line, and when viewed in cross section across the process line, the casing is This is achieved by a heat exchanger plant characterized by being rectangular.

  Each row of such heat exchanger stages, each having a plate package, forms a so-called effect part of the plant. Since a rectangular storage casing is used instead of a conventional cylindrical container, the cost can be greatly reduced. More preferably, the casing shape matches the outer contour formed by the rows of heat exchanger stages in the plant when viewed from the direction across the line. Pressure vessels are usually made to be cylindrical because they are optimally shaped with respect to strength and therefore require minimal material. This principle is not self-evident when the pressure vessel is subjected to excessive external pressure, but the structure may collapse due to instability. In a cylindrical container, when it is deformed slightly to an ellipse, a local bending stress is generated, which causes a deformation, a larger bending stress, and finally the whole collapses. Therefore, a pressure vessel that receives excessive external pressure needs to be dimensioned to have a much higher strength than if it only receives excessive internal pressure of the same magnitude. This is particularly important for vacuum vessels. This is because if the container dimensions are set only in relation to the membrane stress, a small material thickness is sufficient for small pressures, but this material thickness is sufficient to achieve sufficient safety against buckling. This is because the rigidity of the plate is too small. To keep the material from becoming too thick, the casing is provided with a reinforcing ring, but it still needs to be 4-5 times thicker than a cylindrical container that is subjected to excessive internal pressure. Since the desalination plant operates at high vacuum, the above description applies. Cylindrical containers do not save much material compared to square containers, and the more material plates that are placed in the container, the less material that can be saved. Recall that the material constitutes only a small part of the cost of the finished container, and that the structure with the least amount of material does not necessarily have the lowest cost. There are several important factors for overall economics.

  According to a preferred embodiment of the invention, the plant has at least three process lines with continuous heat exchange stages and extending parallel to each other. Thus, each row has three heat exchanger stages that are arranged adjacent to each other and together form an effect part of the plant. Furthermore, the plant advantageously comprises at least four process lines with continuous heat exchange stages and extending parallel to one another. The advantages of a rectangle increase as the plant grows, that is, as the number of parallel process lines it has.

  According to a further embodiment of the invention, each heat exchange stage is configured as a module with a part of the casing, the module being connected to at least one of the successive modules located before and after the same process line flow. Has been. In large plants, it is important to be able to transport easily, minimize customer site work, and reduce work to just installation. All manufacturing that requires confirmation should be done by the supplier or subcontractor. In this regard, the rectangular casing is advantageous because it can be easily divided into two modules that can be reasonably manufactured at the factory and then relatively easily transported to the installation site.

  According to a further embodiment of the invention, each module is either a module adapted to be provided between two adjacent modules in the same row, or adjacent to only one adjacent module in the same row. It is formed as one of the outer modules adapted to be provided. Therefore, there are two modules from a structural point of view. The outer modules exist in the right and left structures, but they can be made perfectly symmetrical, so there is only one configuration. Each module is advantageously adapted to be connected to at least one module adjacent in the same row in the flow direction. Furthermore, a part of the casing of each module is adapted to be mechanically connected to at least one adjacent module in the same row and mechanically connected to at least one of the modules located before and after the same process line. You may be made to connect to.

  According to a further embodiment of the present invention, each process line has at least three consecutive heat exchanger stages, and at least a portion of the liquid evaporated in the second heat exchanger stage is a third heat exchanger. In order to evaporate the liquid supplied to the second inter-plate space of the stage, it is supplied to the first inter-plate space of the third heat exchanger stage. Further, each process line has at least four consecutive heat exchanger stages, and at least a portion of the liquid evaporated in the third heat exchanger stage is in the second interplate space of the fourth heat exchanger stage. For the evaporation of the liquid supplied to the first, it is advantageous to supply the first interplate space of the fourth heat exchanger stage. Of course, each process line may further comprise, for example, 5, 6, 7, 8, 9, or more such continuous heat exchanger stages.

  According to a further embodiment of the invention, the casing is adapted to maintain a lower pressure in the inner space than in the outer side of the casing.

  According to a further embodiment of the invention, the plant is such that the rows of heat exchanger stages extend substantially horizontally.

  According to a further embodiment of the invention, the process line extends substantially horizontally.

  According to a further embodiment of the invention, the plant is such that the process line extends substantially vertically. In very large plants, the cost of the casing can be further reduced if the plate packages are arranged in several rows in several planes. With such a configuration, the outer surface and the required installation area can be minimized.

  According to a further embodiment of the invention, the first interplate space and the second interplate space in the plate package are sealed by a gasket. Thus, the plate package can be opened for cleaning and repair.

  According to a further embodiment of the present invention, a liquid separator connected to substantially all heat exchanger stages is provided.

  According to a further embodiment of the invention, the plant is operated by a supply of high-pressure external steam and mixes the external steam with at least part of the steam produced in at least the last heat exchanger stage. To this end, it has a thermal compressor adapted to receive at least a portion of the steam, and the mixed steam forms steam that is fed to the first heat exchange stage.

  In the following, various embodiments will be described and the present invention will be described in more detail with reference to the accompanying drawings.

  1-4 show a heat exchanger plant for distillation, in particular for seawater desalination. The disclosed heat exchanger plant has four process lines 1. Each process line 1 extending in the longitudinal direction of the plant has five consecutive heat exchanger stages 2a to 2e, each heat exchanger stage has a plate package 3 of heat exchange plates 4, and the heat exchange plates 4 One inter-plate space 5 and second inter-plate space 6 are provided in the plate package 3 so as to be formed. The four process lines 1 extend parallel to each other so that the heat exchanger stages 2a to 2e form five rows 8 of heat exchanger stages 2a to 2e. Each row 8 each comprising a heat exchanger stage 2a, 2b, 2c or 2d forms a so-called effect part.

  These rows 8 are arranged in parallel with each other and extend in the transverse direction of the plant, ie in the direction transverse to the process line 1. The rows 8 extend in a direction substantially perpendicular to the process lines 1 extending longitudinally parallel to each other in the disclosed embodiment. Note that in an alternative configuration plant, the number of columns 8 and process lines 1 may be different from the number of columns 8 and process lines 1 disclosed.

  The plant has a closed casing 10 surrounding an inner space 11 provided with four process lines 1 with heat exchanger stages 2a to 2e. The casing 10 is configured as a pressure vessel that can maintain the inside space 11 at a pressure substantially lower than the ambient atmosphere immediately outside the casing 10. A separating wall 12 extends substantially horizontally in the casing 10 and divides the inner space 11 into two halves extending substantially in the longitudinal direction. Further, the different heat exchanger stages 2a to 2d are separated from each other by walls 18 and 18 'extending in the vertical direction. As shown in FIG. 3, the walls 12, 18, 18 ′ thus form a number of upper spaces 13 and a number of lower spaces 14. Each plate package 3 is provided so as to extend through the separation wall 12, and the upper part of the plate package 3 is located in the upper space 13 and the lower part of the plate package 3 is located in the lower space 14. is doing.

  FIG. 3 shows one of the plate packages 3 in more detail. Each plate package 3 can have a large number, for example 500-1500 heat exchange plates 4. Each plate package 3 can be integrally held by, for example, four fastening bolts (not shown) extending through the frame plate and the pressure plate (not shown) of each plate package 3. Gaskets 15 and 15 ′ for sealing the inter-plate spaces 5 and 6 are provided in the inter-plate spaces 5 and 6 in the plate package 3, respectively. More specifically, the gasket 15 is provided so that the first inter-plate space 5 for condensation is sealed with respect to each lower space 14 shown in FIG. 3, and the gasket 15 'is a second vaporization space. The inter-plate space 6 is provided so as to be sealed with respect to each upper space 13.

  In addition, the plant has a flow path through the separating wall 12 between each heat exchanger stage 2a and 2b, between 2b and 2c, between 2c and 2d, and between 2d and 2e. ing. In substantially all such channels, liquid separators 16a-16d are provided.

  The plant also has a thermal compressor 20 which is adapted to operate in a manner known per se by the supply of high-pressure external steam. External steam is supplied to the thermal compressor 20 through the supply conduit 21. The thermal compressor 20 supplies steam at a certain pressure and a certain temperature through the inlet conduit 22 to the first heat exchanger stage 2a. This pressure and temperature coincide with the pressure and temperature in the first heat exchanger stage 2a, but are lower than the ambient atmospheric pressure and ambient temperature. The temperature and pressure then continue to drop in the subsequent heat exchanger stages 2b-2e. A portion of the steam discharged from one or several of the last heat exchanger stages, in this example the penultimate heat exchanger stage 2d, is returned to the thermal compressor 20 through a conduit 23. The thermal compressor 20 has a nozzle that recirculates the returned steam to the inlet conduit 22 by external steam.

  A liquid to be distilled, in this example a salty liquid, so-called brine, is fed through the supply conduit 30 shown schematically. The supply conduit 30 may be more complicated than that shown in FIG. 1, but is adapted to supply a liquid containing salinity at a temperature adapted to the temperature of each stage 2a-2d. The salt-containing liquid passes through the supply conduit 30 in each plate package 3 and the port channel 31 shown in FIG. 4, and the second in each plate package 3 of the four first heat exchanger stages 2a to 2d. To the inter-plate space 6. The supplied liquid is heated by the vapor in the adjacent first inter-plate space 5, and at least a part thereof is evaporated. The vapor in the first inter-plate space 5 is then condensed and discharged as a liquid through the two port channels 34 in each plate package shown in FIG. 4 and the discharge conduit 35 below it. Here, it should be noted that in the embodiment shown in FIGS. 1 to 4, the last heat exchanger stage 2e is a pure condensation stage for condensing the vapor from the previous heat exchanger stage 2d. Condensation is achieved by circulating external refrigerant through the circulation conduits 32 and appropriate port channels in each plate package 3 of the last heat exchanger stage 2d. At least a part of the external refrigerant may be supplied to the other heat exchanger stages 2 a to 2 d by the supply conduit 30. The heat exchanger stage 2e is used for preheating salt-containing liquid as shown in FIG.

  Each of the heat exchanger stages 2a to 2e is configured to condense the vapor in the first inter-plate space 5 in this way. Further, each of the heat exchanger stages 2a to 2d except the last heat exchanger stage 2e evaporates the liquid in the second inter-plate space 6. More specifically, steam is supplied to the first interplate space 5 of the first heat exchanger stage 2 a through the inlet conduit 22 and the upper space 13. The liquid containing salt is supplied to the second inter-plate space 6 of the first heat exchanger stage 2a through the supply conduit 30. The supplied vapor is condensed into a liquid and discharged from the first heat exchanger stage 2 a through the port channel 34 and the discharge conduit 35. All of the liquid discharged from all heat exchanger stages 2a to 2e through the discharge conduit has a very low salt content and high purity. The supplied liquid is partially evaporated in the lower space 14 and discharged. The vapor can pass from the lower space 14 to the upper space 13 through the first liquid separator 16a. In the disclosed embodiment that does not evaporate, the liquid droplets containing salt are then captured and returned to the lower space 37 in the lower portion of the lower space 14 as excess liquid. Thus, in the disclosed embodiment, the lower space 37 is configured to accommodate an excess liquid containing salt, so-called brine. It should be noted that the salted liquid is supplied several times and then evaporated to ensure that the heat exchange surface in the first inter-plate space 5 is moistened.

  Vapor that passes through the first liquid separator 16a passes through the supply conduit 30 to the second heat due to evaporation of the liquid supplied to the second interplate space 6 of the second heat exchanger stage 2b. It is supplied to the upper space 13 of the exchanger stage 2 b and the first inter-plate space 5. The steam condenses in the first interplate space 5 of the second heat exchanger stage 2 b and is exhausted through the port channel 34 and the exhaust conduit 35 in the plate package 3. The supplied liquid evaporates and is discharged into the lower space 14. The steam can pass from the lower space 14 to the upper space 13 of the third heat exchanger stage 2c through the second liquid separator 16b. In the disclosed embodiment, the liquid containing salt is then captured and returned to the lower space 37 as surplus liquid.

  Vapor passing through the second liquid separator 16b passes through the supply conduit 30 for the third heat to evaporate the liquid supplied to the second interplate space 6 of the third heat exchanger stage 2c. It is supplied to the upper space 13 of the exchanger stage 2 c and the first inter-plate space 5. The steam condenses in the first inter-plate space 5 of the second heat exchanger stage 2 c and is discharged through the port channel 34 and the discharge conduit 35 in the plate package 3. The supplied liquid evaporates and is discharged into the lower space 14. Steam can pass from the lower space 14 to the upper space 13 of the fourth heat exchanger stage 2d through the third liquid separator 16c. In the disclosed embodiment, the liquid containing salt is then captured and returned to the lower space 37 as surplus liquid.

  Vapor passing through the third liquid separator 16c passes through the supply conduit 30 to the fourth heat due to evaporation of the liquid supplied to the second interplate space 6 of the fourth heat exchanger stage 2d. It is supplied to the upper space 13 of the exchanger stage 2d and the first inter-plate space 5. The steam condenses in the first inter-plate space 5 of the fourth heat exchanger stage 2 d and is exhausted through the port channel 34 and the exhaust conduit 35 in the plate package 3. The supplied liquid evaporates and is discharged into the lower space 14. The steam can pass from the lower space 14 to the upper space 13 of the fifth heat exchanger stage 2e through the fourth liquid separator 16d. In the disclosed embodiment, the liquid containing salt is then captured and returned to the lower space 37 as surplus liquid.

  The vapor passing through the fourth liquid separator 16d is supplied to the upper space 13 of the fifth heat exchanger stage 2e. From this upper space, a part of the steam is sucked into the thermal compressor 20 through the conduit 23, and the remaining steam is supplied to the first inter-plate space 5 of the fifth heat exchanger stage 2e. The steam condenses in the first inter-plate space 5 of the fifth heat exchanger stage 2 e and is discharged through the discharge conduit 35. The fifth heat exchanger stage 2e configured to perform final condensation is a stage 2a to 2d in the previous stage, such as a plate package composed of different types of plates or a completely different type of heat exchanger such as a tube condenser. It may have a different type of heat exchanger stage.

  One or several of the heat exchanger stages 2a-2d also have a preheater heater 40 for preheating the salted liquid supplied to the first interplate space 5 through the supply conduit 30. May be. FIG. 1 schematically shows such a preheating heater 40 for preheating a salt-containing liquid by steam supplied to the heat exchanger stage 2c.

  FIG. 3 shows at least part of the excess liquid from the heat exchanger stages 2a, 2b, 2c from its lower space 14 to the lower space 14 in the next row 8 of the heat exchanger stages 2b, 2c, 2d. Note also that it can flow directly through the flash chamber 42. Excess liquid from one row 8 of heat exchanger stages 2a, 2b, 2c passes through one or several conduits 41 to the same pressure as the next row of heat exchanger stages 2b, 2c, 2d. Is transferred into a flush chamber 42. As the pressure drops, the excess liquid evaporates. The liquid formed in this way is transferred through one or several relatively large openings 43 into the lower space of the next row 8 of heat exchanger stages 2b, 2c, 2d.

  The discharge conduit 35 may also be connected to the flash tank 39 downstream of at least some heat exchanger stages, in the disclosed embodiment, downstream of the heat exchanger stages 2b, 2c, 2d. Condensed water from each plate package 3 is transferred through a discharge conduit 35 to a flash tank 39 that is at a lower pressure than in each plate package 3. Since the pressure is lowered, a part of the condensed water is evaporated by flushing. The generated steam is returned to the next row 8 process of the heat exchanger stage through a suitable conduit (not shown). The remaining condensed water is discharged from the tank 39 through the conduit 40.

  The casing 10 is rectangular when viewed in the cross section shown in FIG. The opposing upper and lower side walls 51 and 52 are flat, substantially horizontal, and substantially parallel to each other. The opposing side walls 53, 54 are flat, substantially vertical, and substantially parallel to each other. The plant is also formed from a number of modules 61-63 so that it can be easily prefabricated at the factory and easily installed at the plant installation site. Each of the modules 61 to 63 has one of the plate packages 3 and a part of the casing 10. Each of the modules 61 to 63 is connected to at least one module in the same process line 1 that is forward or backward with respect to the flow direction. Further, each of the modules 61 to 63 is connected to at least one module 61 to 63 in the same row 8 that is adjacent to each other in the flow direction. In the disclosed embodiment, the steam flow can pass from one heat exchanger stage to the next. However, in each row 8, there is no partition between adjacent plate packages. This means that the vapor flow in one process line 1 can diffuse to adjacent process lines 1 in a continuous row 8.

  Each module 61-63 is an inner module 61 that is arranged between two adjacent modules in the same row 8, or only one adjacent module 61, 63 and 61, 62 in the same row 8. Are formed as outer modules 62 to 63 that are arranged adjacent to each other. The inner module 61 is shown in FIG. Each outer module 62, 63 can be formed as a left module 62 or a right module 63. The left module 62 is shown in FIG. 5, and the right module 63 is shown in FIG.

  The aforementioned portion of the casing 10 of each module 61-63 is mechanically coupled to at least one adjacent module 61-63 in the same row 8 and at least one of the modules 61-63 before and after the same process line 8. To be connected to. According to one embodiment, the mechanical connection is made by connecting the modules 61-63 to each other by welding joint, that is, the casing 10 of each module 61-63 is welded to the casing 10 of the adjacent module 61-63. realizable.

  According to other embodiments, each inner module 61 may have a longitudinally extending vertical flange 70 that abuts a corresponding vertically extending flange 70 of the adjacent module 61-63. Accordingly, the modules 61 to 63 can be connected to each other by appropriate bonding such as screw bonding. The outer modules 62 to 63 are different from the inner module 61 because the flange 70 is provided only on one side. Further, each of the modules 61 to 63 may have a vertically extending vertical flange 71 that abuts a corresponding vertically extending flange 71 of an adjacent module 61 to 63 of the same process line 1. . These flanges 71 are shown in FIG. The first and last modules 61 to 63 in each process line may be closed by a cover 73 having an appropriate configuration. Gaskets 74 as shown in FIGS. 5 and 7 may be provided at the longitudinal and transverse joints between the different modules 61 to 63.

  In the disclosed embodiment, the flash tanks 39 are located outside the casing 10, but they can also be arranged in the casing 10.

  9 and 10 schematically show the heat exchanger plant of the second embodiment. In the two embodiments, components having substantially the same function have the same reference numerals. In the second embodiment, the process line 1 including the continuous heat exchanger stages 2a to 2g does not extend horizontally in the longitudinal direction but extends vertically in the longitudinal direction. As in the first embodiment, the row 8 of the plate package 3 extends in the horizontal direction and in the direction crossing the process line 1 extending in the longitudinal direction. The width of the last row 8 provided with the last heat exchanger stage 2g configured for final condensation is wider than the width of the previous row 8 related to the heat exchanger stages 2a to 2f in this embodiment. . The heat exchanger stage 2g shown in FIGS. 9 and 10 is realized by a tube capacitor. The second embodiment is suitable for a very large plant and comprises three thermal compressors 20 with three supply conduits 22 as shown. The casing 10 of this embodiment is substantially a cube. This means that the area of the outer surface of the casing 10 is minimized. The pipe length is very short due to the compact structure. The required installation area is very small compared to the required installation area of the plant having the process lines 1 arranged horizontally.

  The present invention is not limited to the disclosed embodiments, but can be changed or modified within the scope of the following claims.

It is sectional drawing seen from the side of the heat exchanger plant of the 1st Embodiment of this invention. It is sectional drawing seen from the upper direction of the plant of FIG. It is a side view of the heat exchanger stage of the plant of FIG. It is sectional drawing of the plant of FIG. 1 along the IV-IV line. FIG. 2 is a view of a first outer module of the heat exchanger plant of FIG. 1. FIG. 2 is a diagram of an inner module of the heat exchanger plant of FIG. 1. FIG. 3 is a view of a second outer module of the heat exchanger plant of FIG. 1. It is a side view of the plant of FIG. It is sectional drawing seen from the side of the heat exchanger plant of the 2nd Embodiment of this invention. FIG. 10 is a second cross-sectional view of the heat exchanger plant of FIG. 9 along the line XX.

Claims (16)

Having at least one process line (1) with at least two successive heat exchanger stages (2a, 2b), each heat exchanger stage (2a, 2b) being a plate package of heat exchange plates (4) ( 3), and the heat exchange plate (4) includes a first inter-plate space (5) for condensation and a second inter-plate space (6) for evaporation inside the plate package (3). Is formed so that
In each of the heat exchanger stages (2a, 2b), vapor is supplied to the first inter-plate space (5) of the first heat exchanger stage (2a), and liquid is supplied to the second inter-plate space (6). Is supplied, the supplied vapor is condensed into a liquid, the supplied liquid is evaporated, and the liquid supplied to the second inter-plate space (6) of the next heat exchanger stage (2b). In order to evaporate the water, the steam is supplied to the first inter-plate space (5) of the next heat exchanger stage (2b) to condense the vapor and evaporate the liquid.
In an evaporation heat exchanger plant having a closed casing (10) surrounding an inner space (11) in which the process line (1) including the heat exchanger stage (2a, 2b) is provided.
The plant has at least two process lines (1) with the continuous heat exchange stages (2a, 2b);
The at least two process lines (1) extend parallel to each other in the inner space (11), and the heat exchanger stages (2a, 2b) are in the inner space (11) of the casing (10), Forming a row (8) of the heat exchanger stages provided adjacent to each other in a direction transverse to the process line (1);
The casing (10) is rectangular when viewed in cross section across the process line (1);
Evaporation heat exchanger plant.   Evaporation heat exchanger plant according to claim 1, characterized in that it comprises at least three said process lines (1) comprising said continuous heat exchange stages (2a, 2b) and extending parallel to one another.   2. Evaporation heat exchanger plant according to claim 1, characterized in that it comprises at least four said process lines (1) comprising said continuous heat exchange stages (2a, 2b) and extending parallel to one another.   Each of the heat exchange stages (2a, 2b) is configured as a module (61-63) having a part of the casing (10), and the module is positioned before and after the flow direction of the same process line (1). 4. The evaporative heat exchanger plant according to claim 1, wherein the evaporative heat exchanger plant is connected to at least one of the successive modules (61 to 63).   Each module (61-63) is either an inner module (61) adapted to be provided between two adjacent modules in the same row (8) or just the same row (8). Evaporation heat exchanger according to claim 2 or 4, characterized in that it is formed as one of outer modules (62, 63) adapted to be provided adjacent to one adjacent module. plant.   The said each module (61-63) is connected with the at least 1 said module adjacent to the flow direction of the said said row | line | column (8), The 4 or 5 characterized by the above-mentioned. Heat exchanger plant for evaporation.   The part of the casing (10) of each module (61-63) is adapted to be mechanically connected to at least one adjacent module in the same row (8) and the same Evaporation according to any one of claims 4 to 6, characterized in that it is mechanically connected to at least one of the modules located before and after the flow of the process line (1). Heat exchanger plant.   Each process line (1) has at least three consecutive heat exchanger stages (2a-2c), and at least a part of the liquid evaporated in the second heat exchanger stage (2b) Between the first plates of the third heat exchanger stage (2c) for the evaporation of the liquid supplied to the second interplate space (6) of the third heat exchanger stage (2c). Evaporation heat exchanger plant according to any one of claims 1 to 7, characterized in that it is supplied to the space (5).   Each process line (1) has at least four consecutive heat exchanger stages (2a-2d), and at least part of the liquid evaporated in the third heat exchanger stage (2c) Between the first plates of the fourth heat exchanger stage (2d) for the evaporation of the liquid supplied to the second inter-plate space (6) of the fourth heat exchanger stage (2d). Evaporation heat exchanger plant according to claim 8, characterized in that it is supplied to the space (5).   The casing (10) is characterized in that the inside space (11, 13, 14) can be maintained at a substantially lower pressure than the outside of the casing (10). The heat exchanger plant for evaporation according to any one of 9.   11. The plant according to any one of the preceding claims, characterized in that the row (8) of the heat exchanger stages (2a-2d) extends substantially horizontally. Heat exchanger plant for evaporation.   12. A heat exchanger plant for evaporation according to any one of the preceding claims, characterized in that the process line (1) extends substantially horizontally.   12. Evaporation heat exchanger plant according to any one of the preceding claims, characterized in that the plant is such that the process line (1) extends substantially vertically.   The first inter-plate space (5) and the second inter-plate space (6) in the plate package (3) are sealed by a gasket (15). The heat exchanger plant for evaporation according to any one of 13.   Each process line (1) is provided with a liquid separator (16) connected to substantially all the heat exchanger stages (2a, 2b, 2c, 2d), The heat exchanger plant for evaporation according to any one of claims 1 to 14.   In order to mix the external steam with at least a portion of the steam made to operate by the supply of high pressure external steam and at least the last stage heat exchanger stage (2d) A heat compressor (20) adapted to receive a portion, wherein the mixed steam forms the steam supplied to the first heat exchange stage (2a). The heat exchanger plant for evaporation according to any one of 1 to 15.

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