Evaporative wet surface air cooling device
By integrating a spiral plate heat exchanger with evaporative cooling techniques, the WSAC devices achieve improved thermal efficiency and reduced footprint, addressing the issues of high costs and large footprints in conventional designs.
Patent Information
- Application Number
- JP2023538802
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2021-02-23
- Filing Date
- 2021-12-15
- Publication Date
- 2025-05-12
- Estimated Expiration
- 2041-12-15
AI Technical Summary
Existing wet surface air cooling (WSAC) devices have large footprints and high operating costs due to their conventional tube bundle designs and evaporative cooling methods.
The use of a spiral plate heat exchanger in combination with evaporative cooling techniques to enhance the efficiency and compactness of WSAC devices, allowing for a more efficient heat transfer process.
This solution results in a more compact and efficient WSAC with reduced footprint and operational costs, while maintaining or improving thermal performance.
Smart Images

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Abstract
Description
[Technical field]
[0001] The present invention is directed to a wet surface air cooler (WSAC) with reduced cost, reduced footprint and improved thermal performance. [Background technology]
[0002] Existing evaporative cooling technologies, such as existing wet surface air coolers for industrial applications, have a large footprint and high operating costs.
[0003] A conventional Wet Surface Air Cooler (WSAC) (e.g., evaporative cooler) consists of a tube bundle to facilitate process fluid flow, a spray system to distribute water over the top of the tube bundle, and a fan or set of fans to draw air through the tube bundle. The air / spray water mixture on the exterior of the tubes provides an evaporative cooling effect that removes heat from the process fluid and rejects it out of the fan canister and back into the spray water collection sump.
[0004] For example, U.S. Patent No. 6,399,633 (herein the "'862 patent"), which is incorporated by reference in its entirety, discloses an evaporative cooling apparatus including a direct heat transfer section 324 separated from an indirect cooling or indirect heat transfer section 330 by a wall 369 that extends to a liquid collector 338 (e.g., a reservoir) that collects water discharged from nozzles 344 of the direct heat transfer section 324 and from nozzles 382 of the indirect cooling section 330. Pumps 362 and 376 are provided for recirculating water from the liquid collector 338 to the respective nozzles 382, 344 (Figure 7 and paragraph 13 of the '862 patent, lines 31-39). The '862 patent further discloses that direct heat transfer zone 324 includes wet deck flood 326 and drift exclusion 352, with "air flowing in through air inlet 348 and up through flood 326, through drift exclusion 352, past air movement device 328, and out through opening 350" (Figure 7 of the '862 patent, lines 59-62 of paragraph 12, and lines 1-6 of paragraph 14). The '862 patent discloses that to reduce the need for additional flow requirements and reduce the need for "excessive air movement power," it is desirable to have coil 332 outside of the air flow, such that "heat transfer coil 332 is positioned substantially outside of the air flow through the enclosure," which is accomplished by wall 369 (lines 29-32 of paragraph 2, and lines 1-3 of paragraph 14 of the '862 patent). [Prior art documents] [Patent documents]
[0005] [Patent Document 1] U.S. Patent No. 6,598,862 Summary of the Invention [Problem to be solved by the invention]
[0006] The present invention is directed to utilizing a spiral plate heat exchanger for a wet surface air cooler in combination with evaporative cooling technology to provide a more efficient and compact solution for industrial cooling applications. [Means for solving the problem]
[0007] The present invention enhances the evaporative cooling process of WSAC by utilizing an evaporative spiral (i.e., helical) plate heat exchanger instead of a tube bundle, where the evaporative spiral plate heat exchanger is exposed to evaporative cooling. The spiral plate heat exchanger may also be referred to as a spiral heat exchanger. A cooling medium such as water is sprayed onto the outer heat transfer surface of the evaporative spiral plate heat exchanger, and air is either pushed or pulled through the open passages of the evaporative spiral plate heat exchanger via a fan to create the evaporative cooling effect.
[0008] The present invention can function in both co-flow and counter-flow arrangements depending on how the fans are positioned relative to the direction of airflow through the evaporative spiral plate heat exchanger and the direction of the sprayed cooling medium. The present invention may further comprise a direct heat exchange section consisting of a cooling tower which cools the sprayed water and provides a further increase in heat transfer efficiency.
[0009] The wet surface air cooling apparatus (WSAC) includes an evaporative spiral plate heat exchanger including a first passageway configured to receive a process medium, a spraying system configured to spray a cooling medium onto the spiral plate heat exchanger, and a fan configured to flow air through the evaporative spiral plate heat exchanger, wherein a combination of the cooling medium sprayed onto the evaporative spiral plate heat exchanger and the air flowing through the evaporative spiral plate heat exchanger at least partially evaporates the cooling medium to reduce a temperature of the process medium.
[0010] The first passage of the evaporative spiral plate heat exchanger may have a helical shape and include a plurality of turns for flowing the process medium, and the evaporative spiral plate heat exchanger may further include a set of second passages extending axially through the evaporative spiral plate heat exchanger for receiving air and a cooling medium, and each second passage may be disposed between the turns of the first passage.
[0011] The first passage may be a closed path extending between an inlet and an outlet and may be closed at the upper and lower surfaces of the evaporative spiral plate heat exchanger, and the second passage may be open at the upper and lower surfaces of the evaporative spiral plate heat exchanger.
[0012] The inlet may be provided at the radial center of the evaporative spiral plate heat exchanger and the outlet may be provided at the outermost radial surface of the evaporative spiral plate heat exchanger, or the inlet may be provided at the outermost radial surface of the evaporative spiral plate heat exchanger and the outlet may be provided at the radial center of the evaporative spiral plate heat exchanger.
[0013] The evaporative spiral plate heat exchanger may have a cross-flow arrangement in which the direction of air and / or cooling medium flowing through the second passages is perpendicular to the direction of process medium flowing through the first passages.
[0014] The WSAC may further include a lower housing including a plurality of air passages and a reservoir, the reservoir being configured to receive a cooling medium sprayed by the spray system.
[0015] The air flow passages in the lower housing may be configured to direct air from inside the WSAC to outside the WSAC or from outside the WSAC to inside the WSAC.
[0016] The fan may be mounted above the evaporative spiral plate heat exchanger, which may be mounted in the lower housing.
[0017] The lower housing may be a lower module, the fan and spray system may be part of an upper module, the upper module may be configured to be removably fastened to an upper surface of the evaporative spiral plate heat exchanger, and the lower module may be configured to be removably fastened to a lower surface of the evaporative spiral plate heat exchanger.
[0018] The fan, the spray system, and the evaporative spiral plate heat exchanger may be stacked vertically.
[0019] The spray system may be a concentric spray system including a plurality of distribution passages spaced apart from one another to distribute the cooling medium across the evaporative spiral plate heat exchanger.
[0020] The fan may be horizontally spaced from the evaporative spiral plate heat exchanger.
[0021] The WSAC may further include a lower housing including a reservoir, which may be configured to receive a cooling medium sprayed by the spray system, and the fan and evaporative spiral plate heat exchanger may be provided on an upper surface of the lower housing, and the spray system may be provided above the evaporative spiral plate heat exchanger.
[0022] The fan may be configured to force air across the reservoir and through the evaporative spiral plate heat exchanger, or through the evaporative spiral plate heat exchanger and into the reservoir.
[0023] The spiral plate heat exchanger may include at least one spiral sheet wound to form a first passage. The wound at least one spiral sheet may form a second passage. Thus, the spiral plate heat exchanger may include at least one spiral sheet wound to form a first passage and a second passage. The at least one spiral sheet may separate the first passage and the second passage.
[0024] The spiral plate heat exchanger may include a helix formed by at least one wound helical sheet. A spacing member may be attached to the at least one helical sheet to space the windings of the at least one helical sheet. The helix may be surrounded by a substantially cylindrical shell.
[0025] A method of cooling with a wet surface air cooler (WSAC), the WSAC comprising an evaporative spiral plate heat exchanger including a first passage configured to receive a process medium, a spraying system configured to spray a cooling medium into the spiral plate heat exchanger, and a fan configured to flow air through the evaporative spiral plate heat exchanger, the method may include flowing the process medium through the first passage and operating the fan to flow air through the evaporative heat exchanger to at least partially evaporate the cooling medium and reduce a temperature of the process medium simultaneously with spraying the cooling medium by the spraying system.
[0026] The first passage of the evaporative spiral plate heat exchanger may have a helical shape and include a plurality of turns for flowing the process medium, and the evaporative spiral plate heat exchanger may further include a set of second passages extending axially through the evaporative spiral plate heat exchanger, each second passage being disposed between turns of the first passage, and the method further includes flowing the cooling medium and air in the same or opposite directions through the second passages during the step of operating the fan simultaneously with spraying the cooling medium.
[0027] The first passage may be a closed path extending between an inlet and an outlet and may be closed at the upper and lower surfaces of the evaporative spiral plate heat exchanger, and the second passage may be open at the upper and lower surfaces of the evaporative spiral plate heat exchanger, and the method may further include flowing the process medium from the center of the evaporative spiral plate heat exchanger radially outward through the first passage to the outer surface of the evaporative spiral plate heat exchanger, flowing the cooling medium downward via gravity, and flowing air upward opposite to the direction of the cooling medium.
[0028] The first passage may be a closed path extending between an inlet and an outlet and may be closed at the upper and lower surfaces of the evaporative spiral plate heat exchanger, and the second passage may be open at the upper and lower surfaces of the evaporative spiral plate heat exchanger, and the method may further include flowing the process medium from the outer surface of the evaporative spiral plate heat exchanger radially inward through the first passage to the center of the evaporative spiral plate heat exchanger, flowing the cooling medium downward via gravity, and flowing air upward opposite to the direction of the cooling medium.
[0029] The fan and spray system may be part of the upper module, and the WSAC may further include a lower module including a plurality of air passages and a reservoir, and the method may further include removably fastening the upper module to an upper surface of the evaporative spiral plate heat exchanger and the lower module to a lower surface of the evaporative spiral plate heat exchanger.
[0030] The spiral plate heat exchanger of the present invention provides more efficient heat transfer and therefore requires less surface area, resulting in a more compact WSAC with a dramatically reduced footprint over conventional WSACs.
[0031] Further scope of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood, however, that the detailed description and specific examples, while indicating embodiments of the present invention, are given by way of illustration only, since various changes and modifications within the scope of the present invention will become apparent to those skilled in the art from this detailed description.
[0032] The present invention will become more fully understood from the detailed description provided below and the accompanying drawings, which are provided by way of example only and therefore do not limit the invention. [Brief description of the drawings]
[0033] [Figure 1]FIG. 1 is a cross-sectional view of a WSAC according to one embodiment of the present invention. [Diagram 2] FIG. 1 is a cross-sectional perspective view of a WSAC according to one embodiment of the present invention. [Diagram 3] FIG. 1 is a cross-sectional perspective view of an evaporative spiral plate heat exchanger according to an embodiment of the present invention. [Figure 4] FIG. 1 is a cross-sectional view of a WSAC according to one embodiment of the present invention. [Diagram 5] FIG. 1 is a perspective view of a WSAC according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] The present invention will now be described with reference to the accompanying drawings, in which like reference numerals are used throughout the several views to identify the same or similar elements.
[0035] Figure 1 is a cross-sectional view of a WSAC according to an embodiment of the present invention, Figure 2 is a cross-sectional perspective view of a WSAC according to an embodiment of the present invention, and Figure 3 is a cross-sectional perspective view of an evaporative spiral plate heat exchanger according to an embodiment of the present invention.
[0036] The WSAC 1 according to the first embodiment of the present invention comprises an upper module 100, a lower module 200, and an evaporative spiral plate heat exchanger 300.
[0037] The upper module 100 includes a fan 110 (e.g., an exhaust fan) having a fan motor 115, a spray system 120 having a plurality of distribution passages 125, and a first passage 130. The fan 110 and the fan motor 115 may be provided in a housing of the upper module 100. Furthermore, the center of the fan 110 may be centrally located in the upper housing. The distribution passage 125 may be in the form of a nozzle, or a hole in a slotted tube, or the like. The spray system 120 may be a concentric spray system 120, and the plurality of distribution passages 125 may be equally spaced from each other along the periphery of the upper module 100 to distribute the cooling medium across the evaporative spiral plate heat exchanger 300 (i.e., across the top of the evaporative spiral plate heat exchanger 300). Alternatively, multiple distribution passages 125 may have some spacing from each other and may be provided on the surface of the upper module 100 to distribute the cooling medium across the evaporative spiral plate heat exchanger 300 (i.e., across the top of the evaporative spiral plate heat exchanger 300).
[0038] Each of the upper module 100, the lower module 200, and the evaporative spiral plate heat exchanger 300 may be provided with flanges to allow connection between the upper module 100, the lower module 200, and the evaporative spiral plate heat exchanger 300. The lower module 200 may be a lower housing 200.
[0039] The upper module 100 can be removably coupled to the upper surface (e.g., upper flange) of the evaporative spiral plate heat exchanger 300 via fasteners (i.e., bolts, screws, rivets, etc.), and the lower module 200 can be removably coupled to the lower surface (e.g., lower flange) of the evaporative spiral plate heat exchanger 300 via fasteners (i.e., bolts, screws, rivets, etc.). When the spiral plate heat exchanger includes an outer shell 370, the outer shell 370 may be provided with flanges, such as an upper flange and a lower flange. Furthermore, the evaporative spiral plate heat exchanger 300 may be vertically stacked on the lower module 200, and the upper module 100 may be vertically stacked on the evaporative spiral plate heat exchanger 300 such that the upper module 100, the lower module 200, and the evaporative spiral plate heat exchanger 300 are in a vertically stacked configuration, as shown in FIG. 1 and FIG. 2.
[0040] The upper module 100 may be removably coupled to an upper surface of the evaporative spiral plate heat exchanger 300 to allow for easy replacement with other upper modules 100 having different configurations, such as different heights, different fan sizes, and / or different shapes. Similarly, the lower module 200 may be removably coupled to a lower surface of the evaporative spiral plate heat exchanger 300 to allow for easy replacement with other lower modules 200 having a different number or size of air passages 220, different sized reservoirs, and / or different shapes.
[0041] The WSAC1, including the upper module 100, the lower module 200, and the evaporative spiral plate heat exchanger 300, may have a circular cross-sectional shape. The multiple distribution passages 125 of the spray system 120 may be positioned around the periphery of the spray system 120 to form a concentric spray pattern that provides uniform distribution of the cooling medium to the evaporative spiral plate heat exchanger 300. Furthermore, the multiple distribution passages 125 may be evenly spaced or randomly spaced around the periphery of the spray system 120. The spray system 120 may spray water or any other known cooling medium that is collected in the sump 210 onto the evaporative spiral plate heat exchanger 300.
[0042] Alternatively, the upper module 100, lower module 200, and evaporative spiral plate heat exchanger 300 can have any cross-sectional shape, including any polygonal shape (ie, rectangular, pentagonal, hexagonal), elliptical, and the like.
[0043] The lower module 200 includes a reservoir 210 that collects water sprayed from the spray system 120, one or more air passages 220, a pump 230, a first fluid line 232, and a second fluid line 234. The one or more air passages 220 may be evenly spaced around the periphery of the lower module 200, and the number of air passages 220 and the size of each air passage 220 may be varied to optimize airflow through the WSAC1. Additionally, although FIG. 1 illustrates the one or more air passages 220 positioned at an upper portion of the lower module 200, the one or more air passages 220 may be positioned at any height along the lower module 200.
[0044] In a counterflow arrangement of WSAC1, the fan 110 draws air through one or more air passages 220, upward through the evaporative spiral plate heat exchanger 300, and out through the first passage 130. That is, the upward direction of the airflow through WSAC1 is opposite to the downward direction of the cooling medium sprayed by the distribution passages 125 (i.e., due to gravity).
[0045] Alternatively, in a parallel flow arrangement of WSAC1, the fan 110 pushes air down the first passage, down through the evaporative spiral plate heat exchanger 300, and finally out through one or more air passages 220. That is, the downward direction of airflow through WSAC1 is parallel to the downward direction of the cooling medium sprayed by the distribution passages 125.
[0046] The cooling medium collected in the reservoir 210 is recycled by the pump 230, the first fluid line 232, and the second fluid line 234. Specifically, the collected cooling medium is pumped by the pump 230 through the first fluid line 232 and then through the second fluid line 234 to the spray system 120. The spray system 120 sprays the cooling medium into the evaporative spiral plate heat exchanger 300 in a continuous manner via the distribution passage 125. That is, the pump 230 can provide a continuous flow of the cooling medium to the spray system 120, and the spray system 120 can continuously spray the cooling medium into the evaporative spiral plate heat exchanger 300.
[0047] As shown in Figures 2 and 3, the evaporative spiral plate heat exchanger 300 includes an inlet 310, an outlet 320, a first passage 330 (i.e., a first fluid passage), and a second passage 340. The first passage 330 is coupled to the inlet 310 and the outlet 320 and has a spiral configuration (i.e., a helical cross-sectional profile). That is, the first passage 330 begins at the cross-sectional center of the evaporative spiral plate heat exchanger 300 and spirals radially outward to the outlet 320 of the evaporative spiral plate heat exchanger 300. The first passage 330 and the second passage 340 extend substantially parallel to each other.
[0048] Additionally, the evaporative spiral plate heat exchanger 300 may be oriented such that the central axis of the evaporative spiral plate heat exchanger 300 is along the vertical axis of WSAC1 and such that the radial axis of the evaporative spiral plate heat exchanger 300 is along the horizontal axis of WSAC1.
[0049] A spiral plate heat exchanger typically includes two spiral sheets that extend along respective spiral paths around a central axis and form first and second passages that are substantially parallel to each other. A spacing member having a height corresponding to the width of the flow passages may be attached to, and typically welded to, at least one of the sheets to separate the sheets, obtain a desired distance between the sheets, and provide rigidity to the spiral plate heat exchanger, and in particular to the spirals of the spiral plate heat exchanger.
[0050] The spiral plate heat exchanger 300 includes at least one spiral sheet 360 that is wound to form a first passageway 330. The wound at least one spiral sheet 360 also forms a second passageway 340.
[0051] At least one spiral sheet 360 of wrap separates the first passageway 330 and the second passageway 340 .
[0052] The spiral plate heat exchanger 300 includes a spiral 350 formed by at least one wound spiral sheet 360. Spacing members (not shown), such as studs, typically cylindrical studs, may be attached to the at least one sheet 360 to space the windings of the at least one sheet 360.
[0053] The spiral plate heat exchanger 300 comprises a spiral 350. The spiral 350 is formed by at least one spiral sheet 360 that is wound to form the spiral 350. The spiral 350 forms a first spiral passage 330 and a second spiral passage 340.
[0054] The helix 350 is typically formed by two helical sheets 360 of metal that are wound to form the helical first passage 330 and the helical second passage 340. Alternatively, the helix 350 may be formed from a single sheet 360 of metal that extends from the center of the helix 350 and provides two sheet portions that are wound to form the helix 350. The helix 350 may be formed in a conventional manner by winding the two sheets 360 of metal around a retractable mandrel, but may also be formed in other ways. In the figures, the helix 350 is only diagrammatically shown with a few turns, but it is clear that the helix 350 may include further turns and that the turns are formed from the center of the helix 350 outwards around the helix 350. When at least one helical sheet 360 is wound, a turn is formed, more precisely, a plurality of turns are formed.
[0055] The spiral 350 is surrounded by a substantially cylindrical outer shell 370. The spiral 350 may be surrounded by another outer shell 370 (as shown in FIG. 2) or alternatively the sheet 360 forming the spiral may constitute the outer shell 370 by the outer turns of the sheet 360 (as shown in FIG. 3). The spiral 350 comprises a central body 380, which is typically cylindrical. The central body 380 may be formed by a central part of a sheet or by a cylindrical central part. The central body 380 of the spiral plate heat exchanger is covered by a central cover 390, which is welded to the spiral 350, more precisely at each end of the central body 380, i.e. at the upper and lower ends.
[0056] The central body 380 of the helix 350 may be formed by a cylindrical piece to which the ends of each helical sheet 360 are welded. Alternatively, the central body 380 of the helix 350 may be formed by inserting each end of two sheets 360 of metal into opposing slits of a retractable mandrel, as described in WO 2010 / 130580, which is incorporated herein by reference. As a further alternative, the starting material for the helix 350 may be a single sheet 360, in which case a central portion of the single sheet 360 is inserted into the mandrel, and the two sheet portions extending from the central portion are wound to form the helix 350 and the central body 380. A winding machine winds the sheet 360 to form the helix 350. After the winding machine has completed winding the sheet 360 of metal, the helix 350 is removed from the winding machine and the retractable mandrel is removed. The spiral 350 is then moved to a welding station for sealing or closing the first passage 330 and the second passage 340 from each other by hand or by a welding machine by welding together the edges of the turns of the sheet 360, i.e. the top and bottom edges, to each other, so that the first passage 330 is closed and the second passage 340 is open, at the top and bottom. This is done by welding all the second turns open. A central cover 390 is welded to the openings at each end of the central body 380 to obtain a durable sealed central body 380.
[0057] Sheet 360 is a flexible plate that allows for rolling the plate into a helical shape, however, a rolling machine may be required to accomplish rolling the sheet / plate into a helical shape.
[0058] As shown in FIG. 3 and indicated by the arrows, the evaporative spiral plate heat exchanger 300 has a cross-flow arrangement in which the direction of the air and / or cooling medium flowing through the second passages 340 is cross, or perpendicular, to the direction of the process medium flowing through the first passages 330.
[0059] The evaporative spiral plate heat exchanger 300 may include a header coupled to the outlet 320, as shown in FIG. 3, or may be provided without a header, as shown in FIGS. 1, 2, 4, and 5.
[0060] The evaporative spiral plate heat exchanger 300, including the first passage 330, or more precisely, including at least one sheet 360 forming the first passage 330, may be made of a metal material with good thermal conductivity, such as stainless steel, copper, galvanized steel, or any other known material. Furthermore, the first passage 330 can radiate (i.e., conduct) heat away from the process medium toward the second passage 340. Furthermore, the cooling medium sprayed into the evaporative spiral plate heat exchanger 300 is covered along the entire length (i.e., axial length) of the second passage 340 to further conduct heat away from the process medium. The structure of the evaporative spiral plate heat exchanger 300 with vertical passages (second passage 340) allows a heat exchanger design that can maximize the exposure of the air flow and the cooling medium to the heat transfer surface while making optimal use of the available pressure loss, thereby improving the heat dissipation effect of the evaporative spiral plate heat exchanger 300.
[0061] A process medium (e.g., a hot process medium) flows through the evaporative spiral plate heat exchanger 300 by means known in the art. In the present invention, the process medium flows through an inlet 310, through a first passageway 330, and out an outlet 320. The process medium can be any type of hot process medium as known in the art, such as water, glycol, oil, fuel, gas, or for condensing steam, ammonia, propylene, butane, etc.
[0062] Further, as shown in FIG. 2, the inlet connection can extend from the outside of WSAC1 to the cross-sectional center of the evaporative spiral plate heat exchanger 300, and the outlet connection can extend from the outer extent (i.e., the radially outermost extent) of WSAC1.
[0063] FIG. 3 shows the evaporative spiral plate heat exchanger 300 oriented vertically (i.e., vertically) in the same manner as shown in FIGS. 1 and 2 such that air flows axially through the evaporative spiral plate heat exchanger 300, driven by the fan 110.
[0064] That is, the process medium flows radially outward in a spiral manner from an inlet 310 located at the cross-sectional center of the evaporative spiral plate heat exchanger 300 to an outlet 320, which may be located at the periphery or outermost radial surface of the evaporative spiral plate heat exchanger 300. The second passages 340 are located between each turn (e.g., turn) of the first passages 330 to allow air flow around each turn of the first passages 330. That is, the second passages 340 are axial passages that extend in the axial direction (i.e., vertical direction) of the WSAC1 (and similarly in the axial / vertical direction of the evaporative spiral plate heat exchanger 300). The second passages 340 (or set of second passages 340) may be formed by a single continuous spiral passage 340 that extends axially through the evaporative spiral plate heat exchanger 300, and each of the second passages 340 may be connected to each other. That is, each portion of the second passage within each turn of the first passage can be interpreted as one of a plurality of second passages.
[0065] Alternatively, the outlet connection can extend from the exterior of WSAC1 to the cross-sectional center of the evaporative spiral plate heat exchanger 300 and the inlet connection can extend from the exterior extent of WSAC1. That is, the process medium can flow radially inward in a spiral manner from an inlet 320 located at the outermost radial extent of the evaporative spiral plate heat exchanger 300 to an outlet 310 positioned at the radial center of the evaporative spiral plate heat exchanger 300. The second passages 340 are positioned between each turn (e.g., turn) of the first passages 330 to allow air flow around each turn of the first passages 330.
[0066] The airflow generated by the fan can flow from outside WSAC1, through one or more air passages 220, through the second passage 340, and out through the first passage 130. That is, the fan 110 can pull air through WSAC1. Alternatively, the fan 110 can push air through WSAC1 by forcing air from the first passage 130, through the evaporative spiral plate heat exchanger 300, and out through one or more air passages 220 of the lower module.
[0067] The combination of the sprayed cooling medium into the evaporative spiral plate heat exchanger 300 (i.e., second passage 340) and the air flow through the second passage 340 of the evaporative spiral plate heat exchanger 300 causes the cooling medium in the second passage 340 to evaporate, which further increases the thermal conductivity of the evaporative spiral plate heat exchanger 300. That is, the evaporative spiral plate heat exchanger 300 is exposed to the cooling medium sprayed by the spray system 120, vapor in the form of evaporated cooling medium, and air flow via the fan 110 through the air passage 220.
[0068] The mist system 120 of the present invention keeps the surfaces (i.e., vertical surfaces) of the second passages 340 covered (i.e., wet) with cooling medium to improve wetting of the evaporative spiral plate heat exchanger 300 and thus the cooling effect from the mist system 120.
[0069] This evaporative effect of the present invention improves the dissipation of heat from the process medium, thereby improving the efficiency of the WSAC1. Because of the improved thermal efficiency, the WSAC1 of the present invention can have a reduced footprint (i.e., reduced diameter). Furthermore, the vertically stacked configuration of the WSAC1, including the circular cross-sections for the upper module 100, lower module 200, and evaporative spiral plate heat exchanger 300 of the present invention, provides reduced pressure loss on the fan side of the WSAC1 (i.e., in the first passage 130 to increase the efficiency of the WSAC1).
[0070] That is, the helical shape of the evaporative spiral plate heat exchanger 300 allows airflow to pass axially (i.e., through the second passages 340) and have the cooling medium sprayed thereon to contact the entire axial length of each second passage 340. Water contact with the entire axial length of the second passages 340 improves the efficiency of cooling the process medium.
[0071] 4 and 5 are directed to an alternative embodiment of the present invention in which the fan 110 is horizontally spaced from the spray system 120, and each of the fan 110 and the spray system 120 is mounted in a lower housing 200 having a reservoir 210.
[0072] The embodiment of Figures 4 and 5 also includes an evaporative spiral plate heat exchanger 300 with the same structure and orientation as shown in Figures 1-3. Additionally, the embodiment of Figures 4 and 5 operates in a similar manner to the embodiment of Figures 1-3, with the primary difference being the location of the fan 110 relative to the evaporative spiral plate heat exchanger 300.
[0073] Additionally, instead of having an air passage, the embodiment of Figures 4 and 5 includes a second passage 150 positioned on the top surface of the spray system 120 for introducing air into or expelling air from the WSAC1.
[0074] As in the embodiment of Figures 1 and 2, the cooling medium collected in the reservoir 210 of the lower module 200 is pumped by the pump 230 back to the spray system 120 via a first fluid line 232 and a second fluid line 234.
[0075] 4 and 5 can be operated in a counterflow arrangement, where the fan 110 draws air through the first passage 130, down the sump 210, upward through the evaporative spiral plate heat exchanger 300, and out through the second passage 150. That is, the upward direction of airflow through the evaporative spiral plate heat exchanger 300 is opposite the downward direction of the cooling medium sprayed by the distribution passages 125.
[0076] Alternatively, in the parallel flow arrangement of the present invention, the fan 110 pulls air through the second passage 150, down through the evaporative spiral plate heat exchanger 300, across the sump 210, and out through the first passage 130. That is, the downward direction of airflow through the evaporative spiral plate heat exchanger 300 is parallel to the direction of the cooling medium being sprayed by the distribution passages 125.
[0077] The embodiment of Figures 4 and 5 functions in a similar manner to the embodiment of Figures 1-3 described above in that the combination of sprayed cooling medium (i.e., second passages 340) into the evaporative spiral plate heat exchanger 300 and air flow through the second passages 340 of the evaporative spiral plate heat exchanger 300 evaporates the cooling medium in the second passages 340, which further increases the thermal conductivity of the evaporative spiral plate heat exchanger 300. This evaporative effect improves the dissipation of heat from the process medium, thereby improving the efficiency of the WSAC1. Because of the improved thermal efficiency, the WSAC1 according to the present invention can have a reduced footprint.
[0078] The spray system 120 may be removably coupled to an upper surface of the evaporative spiral plate heat exchanger 300, as shown in Figures 4 and 5. Additionally, the evaporative spiral plate heat exchanger 300 may be removably coupled to an upper surface of the lower housing 200 that includes the reservoir 210. Similarly, the fan 110 may be removably coupled to an upper surface of the lower housing 200 and may be horizontally spaced from the evaporative spiral plate heat exchanger 300.
[0079] 1-3 above, the embodiment of Figures 4 and 5 may be modular. The fan 110 may be a first module, the evaporative spiral plate heat exchanger 300 or the combination of the evaporative spiral plate heat exchanger 300 with the spray system 120 may be a second module, and the reservoir may be a third module. The first, second, and third modules may be replaced with other modules having different flow characteristics, including modules having different configurations, such as different heights, different fan sizes, and / or different shapes, as known in the art.
[0080] As described above with respect to the upper module 100, the lower module 200, and the evaporative spiral plate heat exchanger 300, the first module, the second module, and the third module may be provided with flanges to allow connection between the first module, the second module, and the third module. If the spiral plate heat exchanger includes a shell 370, the shell 370 of the spiral plate heat exchanger 300 may be provided with a flange.
[0081] Additionally, the evaporative spiral plate heat exchanger 300 may be oriented such that the central axis of the evaporative spiral plate heat exchanger 300 is along the vertical axis of WSAC1 and such that the radial axis of the evaporative spiral plate heat exchanger 300 is along the horizontal axis of WSAC1.
[0082] The present invention is not limited to the examples shown in Figures 1-5 and can have different shapes and configurations.
[0083] The disclosure set forth above is not limited to the materials and features described herein, which may be modified within the knowledge of one of ordinary skill in the art. [Explanation of symbols]
[0084] 1 Wet Surface Air Cooler (WSAC) 100 Upper Module 110 Fan 115 Fan motor 120 Spray system, concentric spray system 125 Distribution aisle 130 First Passage 150 Second Passage 200 Lower module, lower housing 210 Reservoir 220 Air flow path 230 Pump 232 First fluid piping 234 Second Fluid Piping 300 Evaporative Spiral Plate Heat Exchanger 310 Entrance, exit 320 Exit, Entrance 330 First Passage 340 Second Passage 350 Spiral 360 Spiral Sheet 370 Shell 380 Centrosome 390 Center Cover
Claims
1. an evaporative spiral plate heat exchanger (300) including a first passage (330) configured to receive a process medium; a spray system (120) configured to spray a cooling medium onto the evaporative spiral plate heat exchanger (300); a fan (110) configured to blow air through the evaporative spiral plate heat exchanger (300); A wet surface air cooling device (WSAC) (1) comprising: a combination of the cooling medium sprayed into the evaporative spiral plate heat exchanger (300) and the air flowing through the evaporative spiral plate heat exchanger (300) causes the cooling medium to at least partially evaporate and reduce the temperature of the process medium; The WSAC further comprises a lower housing (200) including a plurality of air passages (220) and a reservoir (210); the reservoir (210) is configured to receive the cooling medium sprayed by the spray system (120); the lower housing (200) is a lower module (200), and the fan (110) and the spray system (120) are part of an upper module (100); The upper module (100) is configured to be removably fastened to an upper surface of the evaporative spiral plate heat exchanger (300), and the lower module (200) is configured to be removably fastened to a lower surface of the evaporative spiral plate heat exchanger (300).
2. the first passage (330) of the evaporative spiral plate heat exchanger (300) has a helical shape and includes a plurality of turns for flowing the process medium; the evaporative spiral plate heat exchanger (300) further includes a set of second passages (340) extending axially through the evaporative spiral plate heat exchanger (300) for receiving air and a cooling medium; The wet surface air cooling apparatus (WSAC) of claim 1, wherein each second passage (340) is disposed between turns of the first passage (330).
3. the first passage (330) is a closed path extending between an inlet and an outlet (310, 320) and is closed at the upper and lower surfaces of the evaporative spiral plate heat exchanger (300); The wet surface air cooling apparatus (WSAC) of claim 2, wherein the second passages (340) are open at the top and bottom surfaces of the evaporative spiral plate heat exchanger (300).
4. the inlet (310) is provided at the radial center of the evaporative spiral plate heat exchanger (300) and the outlet (320) is provided at the outermost radial surface of the evaporative spiral plate heat exchanger (300); or 4. The wet surface air cooling apparatus (WSAC) of claim 3, wherein the inlet (320) is disposed at the outermost radial surface of the evaporative spiral plate heat exchanger (300) and the outlet (310) is disposed at the radial center of the evaporative spiral plate heat exchanger (300).
5. 5. The wet surface air cooling apparatus (WSAC) of claim 2, wherein the evaporative spiral plate heat exchanger (300) has a cross-flow arrangement in which a direction of air and / or the cooling medium flowing through the second passage (340) is perpendicular to a direction of the process medium flowing through the first passage (330).
6. 6. The wet surface air cooling apparatus (WSAC) of claim 1, wherein the air flow path (220) of the lower housing (200) is configured to flow air from inside the wet surface air cooling apparatus (WSAC) (1) to outside the wet surface air cooling apparatus (WSAC) (1) or from outside the wet surface air cooling apparatus (WSAC) (1) to inside the wet surface air cooling apparatus (WSAC) (1).
7. The fan (110) is provided above the evaporative spiral plate heat exchanger (300), The wet surface air cooling apparatus (WSAC) of any one of claims 1 to 6, wherein the evaporative spiral plate heat exchanger (300) is mounted in the lower housing (200).
8. The wet surface air cooling apparatus (WSAC) of any one of claims 1 to 7, wherein the fan (110), the spray system (120), and the evaporative spiral plate heat exchanger (300) are stacked in a vertical direction.
9. 9. The wet surface air cooling apparatus (WSAC) of claim 1, wherein the spray system (120) is a concentric spray system including a plurality of distribution passages (125) spaced apart from one another to distribute the cooling medium across the evaporative spiral plate heat exchanger (300).
10. The wet surface air cooling apparatus (WSAC) of any one of claims 1 to 5, wherein the fan (110) is horizontally spaced from the evaporative spiral plate heat exchanger (300).
11. Further comprising a lower housing (200) including a reservoir portion (210); the reservoir (210) is configured to receive the cooling medium sprayed by the spray system (120); The fan (110) and the evaporative spiral plate heat exchanger (300) are provided on the upper surface of the lower housing (200); The wet surface air cooling apparatus (WSAC) of claim 10, wherein the fogging system (120) is disposed above the evaporative spiral plate heat exchanger (300).
12. 12. The wet surface air cooling apparatus (WSAC) of claim 11, wherein the fan (110) is configured to force air across the reservoir (210) and through the evaporative spiral plate heat exchanger (300) or through the evaporative spiral plate heat exchanger (300) and into the reservoir (210).
13. 13. The wet surface air cooling apparatus (WSAC) of claim 1, wherein the evaporative spiral plate heat exchanger (300) comprises at least one spiral sheet (360) wound to form the first passage (330).
14. A method for cooling with a wet surface air cooling device (WSAC) (1), comprising: an evaporative spiral plate heat exchanger (300) including a first passage (330) configured to receive a process medium; a spray system (120) configured to spray a cooling medium onto the evaporative spiral plate heat exchanger (300); a fan (110) configured to blow air through the evaporative spiral plate heat exchanger (300); The method comprises: flowing the process medium through the first passageway (330); operating the fan (110) simultaneously with spraying the cooling medium via the spray system (120) to flow air through the evaporative spiral plate heat exchanger (300) and at least partially evaporate the cooling medium to reduce a temperature of the process medium; Including, the fan (110) and the spray system (120) are part of an upper module (100), and the wet surface air cooling apparatus (WSAC) (1) further comprises a lower module (200) including a plurality of air passages (220) and a reservoir (210); The method further includes the steps of releasably fastening the upper module (100) to an upper surface of the evaporative spiral plate heat exchanger (300) and releasably fastening the lower module (200) to a lower surface of the evaporative spiral plate heat exchanger (300).
15. the first passage (330) of the evaporative spiral plate heat exchanger has a helical shape and includes a plurality of turns for flowing the process medium; The evaporative spiral plate heat exchanger (300) further includes a set of second passages (340) extending axially through the evaporative spiral plate heat exchanger (300); Each second passage (340) is provided between turns of the first passage (330); 15. The method of claim 14, further comprising flowing the cooling medium and air in the same or opposite directions through the second passageway during the step of operating the fan simultaneously with spraying the cooling medium.
16. the first passage (330) is a closed path extending between an inlet and an outlet (310, 320) and is closed at the upper and lower surfaces of the evaporative spiral plate heat exchanger (300); The second passages (340) are open at the top and bottom surfaces of the evaporative spiral plate heat exchanger (300), and the method comprises: flowing the process medium from a center of the evaporative spiral plate heat exchanger (300) radially outward through the first passages (330) to an exterior surface of the evaporative spiral plate heat exchanger (300); allowing the cooling medium to flow downwardly via gravity; directing the air upwardly against a direction of the cooling medium; The method of claim 15 further comprising:
17. the first passage (330) is a closed path extending between an inlet and an outlet (310, 320) and is closed at the upper and lower surfaces of the evaporative spiral plate heat exchanger (300); The second passages (340) are open at the top and bottom surfaces of the evaporative spiral plate heat exchanger (300), and the method comprises: flowing the process medium from an exterior surface of the evaporative spiral plate heat exchanger (300) radially inward through the first passages (330) to a center of the evaporative spiral plate heat exchanger (300); allowing the cooling medium to flow downwardly via gravity; directing the air upwardly against a direction of the cooling medium; The method of claim 15 further comprising:
18. 18. The method according to any one of claims 14 to 17, wherein the evaporative spiral plate heat exchanger (300) comprises at least one spiral sheet (360) wound to form the first passages (330).
Citation Information
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