Counter-flow type evaporative cooling tower and heat exchange method

Abstract

The invention provides a counter-flow type evaporative cooling tower and a heat exchange method. The counter-flow type evaporative cooling tower comprises a closed tower body, an induced draft fan, a heat exchange tube bundle, a spraying device and a spraying cooling device. The closed tower body is sequentially provided with a first air inlet end, a cooling area, an air mixing area, a heat exchange area and a second air inlet end from one side to the other side, an air outlet end is arranged at the position, corresponding to the air mixing area, of the closed tower body, a water storage area is formed below the cooling area, the air mixing area and the heat exchange area in the closed tower body, and the induced draft fan is arranged at the air outlet end; the heat exchange tube bundle is arranged in the heat exchange area in the vertical direction, a circulating water inlet is formed in the lower end of the heat exchange tube bundle, and a circulating water outlet is formed in the upper end of the heat exchange tube bundle. The spraying device is arranged between the heat exchange tube bundle and the water storage area; and the spraying cooling device is arranged in the cooling area. The water-water heat exchanger has the advantages that external circulating water is sprayed to the outer surface of the heat exchange tube bundle through the spraying device, and internal circulating water and the external circulating water are in a reverse flow type, so that the water-water heat exchange efficiency can be greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of cooling towers, and particularly to a countercurrent evaporation cooling tower and a heat exchange method.

Background Art

[0002] An evaporation cooling tower is a device that uses the principle of water evaporation to absorb heat and is widely used in multiple fields such as industry, energy, and construction. The evaporation cooling tower includes an internal circulation and an external circulation. Among them, the internal circulation: high-temperature circulating water enters the heat exchange tube bundle of the evaporation cooling tower and exchanges heat with the spray water outside the heat exchange tube bundle, so that the high-temperature circulating water is cooled to the required process temperature; the external circulation: uses a water pump to pump water and spray it outside the heat exchange tube bundle, and at the same time uses a fan to drive the air inside the tower to flow, so that the spray water fully contacts the heat exchange tube bundle and the air to achieve heat and mass transfer, thereby taking away the heat of the high-temperature circulating water inside the heat exchange tube bundle and achieving a cooling effect.

[0003] However, the internal circulation and external circulation of existing evaporation cooling towers usually adopt a cross-flow type, and the spray water adopts a low-pressure split spraying method, resulting in a poor thin water film effect and poor heat exchange efficiency; at the same time, the spray water of the evaporation cooling tower is in open contact with the ambient air, usually only a louver grille is set at the air inlet, and conventional production water is used as the spray water, with a low concentration ratio and difficult water quality control, and various soft and hard scales are easily formed on the heat exchange tube bundle, resulting in a rapid attenuation of the heat exchange efficiency. In view of the above problems, the inventor of this case has conducted in-depth research on this problem, and thus this case has been produced.

Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a countercurrent evaporation cooling tower and a heat exchange method, which solve the problems of poor heat exchange efficiency and easy scaling of the heat exchange tube bundle in existing evaporation cooling towers, resulting in a rapid attenuation of the heat exchange efficiency.

[0005] The present invention is implemented as follows:

[0006] In a first aspect, a countercurrent evaporation cooling tower includes a closed tower body, a draft fan, heat exchange tube bundles, a spraying device, and a spray cooling device; the closed tower body is sequentially provided with a first air inlet end, a cooling area, an air mixing area, a heat exchange area, and a second air inlet end from one side to the other side. An air outlet end is provided at a position corresponding to the air mixing area of the closed tower body. A water storage area is formed below the cooling area, the air mixing area, and the heat exchange area inside the closed tower body. The draft fan is arranged at the air outlet end; the heat exchange tube bundles are arranged vertically in the heat exchange area. A circulating water inlet is provided at the lower end of the heat exchange tube bundles, and a circulating water outlet is provided at the upper end of the heat exchange tube bundles; the spraying device is arranged between the heat exchange tube bundles and the water storage area, and external circulating water is extracted from the water storage area through the spraying device and sprayed onto the outer surface of the heat exchange tube bundles; the spray cooling device is arranged in the cooling area, and external circulating water is extracted from the water storage area through the spray cooling device for spray cooling.

[0007] Further, a plurality of heat exchange tube bundles are arranged in the heat exchange area from left to right. Each heat exchange tube bundle includes a plurality of heat exchange plate tubes arranged from front to back, and the heat exchange plate tubes on each heat exchange tube bundle are arranged in alignment with each other.

[0008] Further, the spraying device includes a spray head, a high-pressure spray pump, a shunt pipeline, and a first conveying pipeline;

[0009] A plurality of shunt pipelines are arranged from bottom to top between adjacent two heat exchange plate tubes and on the front and back sides of the heat exchange tube bundles. A plurality of spray heads are arranged on each shunt pipeline, and the spray ports of the spray heads face the outer surface of the heat exchange plate tubes; each shunt pipeline is connected to the high-pressure spray pump through the first conveying pipeline. The high-pressure spray pump is connected to the water storage area, and a filtering device is provided at the input end of the high-pressure spray pump.

[0010] Further, the spray head adopts a wide-angle fan-shaped spray head.

[0011] Further, the spray cooling device includes a filler with a honeycomb hole structure, a spray pipe, a second conveying pipeline, and a spray pump;

[0012] The filler is arranged in the cooling area. The spray pipe is arranged above the filler, and the spray pipe is connected to the spray pump through the second conveying pipeline. The spray pump is connected to the water storage area.

[0013] Further, a baffle is arranged between the cooling area, the air mixing area, the heat exchange area and the water storage area; a water collecting tank and a water purification tank are formed in the water storage area. Water inlet holes for connecting the cooling area and the heat exchange area to the water collecting tank are formed on the baffle. The spraying device is connected to the water purification tank, and the spray cooling device is connected to the water collecting tank.

[0014] Further, the water collecting tank and the water purification tank are separated by an overflow plate. At the upper end of the overflow plate, a suspended matter filter screen is provided on one side of the water purification tank, and the height of the overflow plate is lower than the heights around the water collecting tank and the water purification tank.

[0015] Further, a water collector is provided at the second air inlet end of the closed tower body.

[0016] In a second aspect, a heat exchange method for a counterflow evaporation cooling tower includes the following steps:

[0017] The internal circulating water is conveyed into the tubes of the heat exchange tube bundle through the circulating water inlet at the lower end of the heat exchange tube bundle. The spraying device is controlled to extract the external circulating water from the water storage area and spray it outside the tubes of the heat exchange tube bundle, so that a thin water film flowing in the opposite direction to the internal circulating water is formed on the outer side of the heat exchange tube bundle. At the same time, the induced draft fan is controlled to draw the external natural wind into the closed tower body through the first air inlet end and the second air inlet end. The external natural wind drawn in from the second air inlet end passes through the heat exchange tube bundle in a cross-flow manner, so that the external natural wind and the external circulating water jointly carry out contact heat exchange with the outer side of the heat exchange tube bundle. The external natural wind drawn in from the first air inlet end passes through the spray cooling device in a cross-flow manner, and the spray cooling device is controlled to extract the external circulating water from the water storage area for spraying, so that the external natural wind exchanges heat with the sprayed external circulating water. The two streams of external natural wind after heat exchange are mixed in the air mixing area and discharged through the induced draft fan. The external circulating water after heat exchange flows into the water storage area, and the internal circulating water after heat exchange is output through the circulating water outlet.

[0018] Further, the spraying device is controlled to extract the external circulating water from the water purification tank in the water storage area, the spray cooling device is controlled to extract the external circulating water from the water collecting tank in the water storage area, and the external circulating water after heat exchange flows into the water collecting tank in the water storage area. The external circulating water in the water collecting tank enters the water purification tank in an overflow manner.

[0019] By adopting the technical solution of the present invention, at least the following beneficial effects are achieved:

[0020] 1. By arranging the heat exchange tube bundle vertically in the heat exchange area, setting a circulating water inlet at the lower end of the heat exchange tube bundle, and a circulating water outlet at the upper end of the heat exchange tube bundle. At the same time, using a spraying device to extract the external circulating water from the water storage area and spray it onto the outer surface of the heat exchange tube bundle. When working specifically, on the one hand, the internal circulating water and the external circulating water are in a countercurrent type, which can greatly improve the water-water heat exchange efficiency; on the other hand, using the spraying device to spray the external circulating water onto the outer surface of the heat exchange tube bundle can form a high-pressure sprayed thin water film between the external circulating water and the heat exchange tube bundle. And the formed thin water film is more uniform, has no dead angle, and is thinner than the traditional low-pressure splashing type. At the same time, the spraying flow rate is faster, with the effect of impact splashing, which can enhance the heat exchange between the air and the external circulating water in the gap of the heat exchange tube bundle, thus greatly strengthening the water-water heat exchange effect; in addition, when dirt adheres to the outer surface of the heat exchange tube bundle, the sprayed external circulating water can also be used to wash away the dirt to reduce the reduction of the heat exchange performance due to fouling on the outer surface of the heat exchange tube bundle; on the third hand, using the spray cooling device to spray the external circulating water in the water storage area onto the cooling area for cooling helps to enhance the heat exchange effect between the external circulating water and the internal circulating water.

[0021] 2. By arranging a filtering device at the input end of the high-pressure injection pump, on the one hand, it can prevent the high-pressure injection pump from being blocked by foreign objects drawn in, resulting in the nozzle being blocked; on the other hand, it can improve the water quality of the external circulating water sprayed onto the heat exchange tube bundle to reduce the fouling on the surface of the heat exchange tube bundle.

[0022] 3. By designing the spray cooling device to include a filler with a honeycomb hole structure, a spray pipe located above the filler, and a second delivery pipeline connecting the spray pipe and the spray pump. When working specifically, it can not only spray the external circulating water in the water storage area onto the filler to exchange heat with the external natural hot air, thereby reducing the temperature of the external circulating water; but also the filler with a honeycomb hole structure can play a role in dust filtration for the inhaled external natural hot air, and the sprayed external circulating water can also play a certain role in dust filtration, so that the dust and other impurities carried in the external natural air will not enter the air mixing area, thereby effectively reducing the fouling on the outer surface of the heat exchange tube bundle.

[0023] 4. By forming a water collection tank and a water purification tank in the water storage area, connecting the cooling area and the heat exchange area to the water collection tank, connecting the spray cooling device to the water collection tank, connecting the injection device to the water purification tank, and arranging a suspended matter filter screen at the upper end of the overflow plate between the water collection tank and the water purification tank; during specific use, on the one hand, the spray cooling device can extract the external circulating water from the water collection tank for spray cooling, and the external circulating water after heat exchange in the heat exchange area and the external circulating water after cooling in the cooling area can both be collected into the water collection tank. In this way, it can better cool the used external circulating water to ensure the subsequent heat exchange effect, and at the same time, the used external circulating water can form precipitation in the water collection tank to filter out impurities such as particulate matter in the external circulating water; on the other hand, the external circulating water after precipitation and cooling can enter the suspended matter filter screen in an overflow manner and then enter the water purification tank through the suspended matter filter screen. This can ensure the water quality of the external circulating water extracted by the injection device, so as to ensure that the surface of the heat exchange tube bundle is not prone to fouling after the external circulating water is sprayed onto it, and the heat exchange performance of the heat exchange tube bundle can be guaranteed.

[0024] 5. By arranging a water collector at the second air inlet end, on the one hand, it can prevent the external circulating water sprayed by the injection device from splashing outside the closed cooling tower, thus avoiding waste of water resources; on the other hand, the water collector can be used to isolate the external environment, preventing impurities such as dust in the external environment from entering the closed cooling tower through the second air inlet end along with the external natural wind and having an adverse effect on the heat exchange tube bundle.

[0025] 6. By arranging a filler with a honeycomb hole structure in the cooling area near the first air inlet end and a water collector at the second air inlet end, it can effectively reduce the contact between the external circulating water and the external environment, reduce the natural evaporation amount of the external circulating water, play a role in saving water, and can also play a role in dust removal and filtration for the external natural hot air to reduce the pollution of the external circulating water by the external environment; at the same time, the injection device extracts the external circulating water that has been treated by precipitation in the water collection tank, filtration by the suspended matter filter screen, and filtration by the filtration device, which can effectively reduce the fouling of the heat exchange tube bundle. Especially when the external circulating water uses softened water, it can effectively increase the concentration ratio, reduce the formation of hard scale on the heat exchange tube bundle, thereby increasing the service life of the equipment and enabling the equipment to maintain high-efficiency heat exchange performance without attenuation for a long time.

Description of the Drawings

[0026] The following further describes the present invention with reference to the accompanying drawings in conjunction with embodiments.

[0027] Figure 1 is the front view of a countercurrent evaporation cooling tower of the present invention;

[0028] Figure 2 is the top view of a countercurrent evaporation cooling tower of the present invention;

[0029] Figure 3 is Figure 2 a partial enlarged view of part A in

[0030] Figure 4 is the structural diagram of the closed tower body in the present invention.

[0031] Explanation of reference numerals:

[0032] Countercurrent evaporative cooling tower 100;

[0033] Closed tower body 1, first air inlet end 11, cooling area 12, air mixing area 13, heat exchange area 14, second air inlet end 15, air outlet end 16, water storage area 17, baffle 18, water inlet hole 181;

[0034] Induced draft fan 2;

[0035] Heat exchange tube bundle 3, circulating water inlet 31, circulating water outlet 32, heat exchange plate tube 33;

[0036] Injection device 4, nozzle 41, high-pressure injection pump 42, shunt pipeline 43, first conveying pipeline 44, filtering device 45;

[0037] Spray cooling device 5, packing 51, spray pipe 52, second conveying pipeline 53, spray pump 54;

[0038] Water collecting tank 61, clean water tank 62, overflow plate 63, suspended matter filter screen 64;

[0039] Water eliminator 7.

Detailed implementation manners

[0040] In order to better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings of the specification and specific implementation manners.

[0041] It should be noted here that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing these implementation manners and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features.

[0042] Example 1

[0043] Please refer to Figures 1 to 4 As shown, a countercurrent evaporation cooling tower 100 of the present invention, the countercurrent evaporation cooling tower 100 includes a closed tower body 1, a draft fan 2, a heat exchange tube bundle 3, a spraying device 4 and a spray cooling device 5, wherein: the draft fan 2 is used to introduce external natural wind into the closed tower body 1, the heat exchange tube bundle 3 is the core component for realizing heat exchange, the spraying device 4 is used to spray water onto the heat exchange tube bundle 3, and the spray cooling device 5 is used to cool the sprayed water;

[0044] The closed tower body 1 is sequentially provided with a first air inlet end 11, a cooling area 12, an air mixing area 13, a heat exchange area 14 and a second air inlet end 15 from one side to the other side. The closed tower body 1 is provided with an air outlet end 16 at a position corresponding to the air mixing area 13. The air outlet end 16 can be specifically arranged at the top of the closed tower body 1. A water storage area 17 is formed below the cooling area 12, the air mixing area 13 and the heat exchange area 14 inside the closed tower body 1; the draft fan 2 is arranged at the air outlet end 16. During operation, under the suction of the draft fan 2, external natural wind can enter the closed tower body 1 from the first air inlet end 11 and the second air inlet end 15; the heat exchange tube bundle 3 is arranged vertically in the heat exchange area 14. A circulating water inlet 31 is provided at the lower end of the heat exchange tube bundle 3, and a circulating water outlet 32 is provided at the upper end of the heat exchange tube bundle 3. During operation, the internal circulating water (i.e., high-temperature circulating water) needs to be transported into the heat exchange tube bundle 3 through the circulating water inlet 31 for heat exchange and cooling, and the process circulating water after heat exchange and cooling is transported to the required equipment for use through the circulating water outlet 32; the spraying device 4 is arranged between the heat exchange tube bundle 3 and the water storage area 17, and the external circulating water is extracted from the water storage area 17 through the spraying device 4 and sprayed onto the outer surface of the heat exchange tube bundle 3; the spray cooling device 5 is arranged in the cooling area 12, and the external circulating water is extracted from the water storage area 17 through the spray cooling device 5 for spray cooling.

[0045] In the present invention, the heat exchange tube bundle 3 is arranged vertically in the heat exchange area 14, a circulating water inlet 31 is provided at the lower end of the heat exchange tube bundle 3, and a circulating water outlet 32 is provided at the upper end of the heat exchange tube bundle 3. Meanwhile, the jetting device 4 is used to extract the external circulating water from the water storage area 17 and jet it onto the outer surface of the heat exchange tube bundle 3. When in specific operation, on the one hand, the internal circulating water and the external circulating water are in a countercurrent type, which can greatly improve the water-water heat exchange efficiency; on the other hand, by using the jetting device 4 to jet the external circulating water onto the outer surface of the heat exchange tube bundle 3, a high-pressure jet thin water film can be formed between the external circulating water and the heat exchange tube bundle 3. The formed thin water film is more uniform, has no dead corners, is thinner than the traditional low-pressure splash type, and at the same time has a faster jetting flow rate and an impact splashing effect, which can enhance the heat exchange between the air and the external circulating water in the gap of the heat exchange tube bundle 3, thus greatly strengthening the water-water heat exchange effect; in addition, when dirt adheres to the outer surface of the heat exchange tube bundle 3, the dirt can also be washed away by the jetted external circulating water to reduce the reduction of the heat exchange performance due to fouling on the outer surface of the heat exchange tube bundle 3; on the third hand, the spray cooling device 5 is used to spray the external circulating water in the water storage area 17 onto the cooling area 12 for cooling, which helps to enhance the heat exchange effect between the external circulating water and the internal circulating water.

[0046] In some embodiments of the present invention, in order to ensure the heat exchange effect, a plurality of heat exchange tube bundles 3 are arranged in a row from left to right in the heat exchange area 14. The specific number of the heat exchange tube bundles 3 can be set according to actual needs; each heat exchange tube bundle 3 includes a plurality of heat exchange plate tubes 33 arranged in a row from front to back, and the heat exchange plate tubes 33 on each heat exchange tube bundle 3 are arranged in alignment with each other. By arranging the heat exchange plate tubes 33 on each heat exchange tube bundle 3 in alignment with each other, on the one hand, the overall structure can be made more compact and beautiful, and on the other hand, it is more convenient to arrange the nozzles 41 between two adjacent heat exchange plate tubes 33.

[0047] In some embodiments of the present invention, the jetting device 4 includes a nozzle 41, a high-pressure jet pump 42, a shunt pipeline 43, and a first conveying pipeline 44;

[0048] There are several shunt pipes 43 arranged from bottom to top between two adjacent heat exchange tube plates 33 and on the front and back sides of the heat exchange tube bundle 3. The specific number of the shunt pipes 43 can be set according to actual needs. For example, as a specific embodiment of the present invention, 3 shunt pipes 43 are arranged from bottom to top between two adjacent heat exchange tube plates 33 and on the front and back sides of the heat exchange tube bundle 3; several nozzles 41 are arranged on each shunt pipe 43, and the jet orifices of the nozzles 41 face the outer surface of the heat exchange tube plate 33. When the present invention is specifically implemented, for the shunt pipes 43 between two adjacent heat exchange tube plates 33, the nozzles 41 can be arranged on both sides of the shunt pipe 43, while for the shunt pipes 43 on the front and back sides of the heat exchange tube bundle 3, only the nozzles 41 are arranged on the side of the shunt pipe 43 close to the heat exchange tube bundle 3, so that the nozzles 41 can accurately spray the external circulating water onto the outer surface of the heat exchange tube plate 33 and form an impact and splashing effect; each shunt pipe 43 is connected to a high-pressure injection pump 42 through a first delivery pipeline 44, the high-pressure injection pump 42 is connected to a water storage area 17, and a filtering device 45 is arranged at the input end of the high-pressure injection pump 42. When the injection device 4 works, the high-pressure injection pump 42 extracts the external circulating water from the water storage area 17 and conveys the external circulating water to each nozzle 41 through the first delivery pipeline 44 and each shunt pipe 43, so that the nozzles 41 can spray the external circulating water onto the outer surface of the heat exchange tube plate 33. By arranging the filtering device 45 at the input end of the high-pressure injection pump 42, on the one hand, it can prevent the nozzles 41 from being blocked due to foreign matters being drawn into the high-pressure injection pump 42, and on the other hand, it can improve the water quality of the external circulating water sprayed onto the heat exchange tube bundle 3 to reduce the scaling on the surface of the heat exchange tube bundle 3.

[0049] As a specific embodiment of the present invention, the nozzle 41 adopts a wide-angle fan-shaped nozzle, so that the thin water film formed after the nozzle 41 sprays is more uniform and has a larger coverage range, thereby improving the heat exchange effect. By adopting the wide-angle fan-shaped nozzle and the high-pressure injection pump 42 to replace the traditional low-pressure splashing spray method, the present invention can ensure that the formed thin water film is more uniform, has no dead angle, and is thinner than the traditional low-pressure splashing spray.

[0050] In some embodiments of the present invention, the spray cooling device 5 includes a filler 51 with a honeycomb hole structure, a spray pipe 52, a second delivery pipeline 53, and a spray pump 54;

[0051] The filler 51 is arranged in the cooling area 12. The spray pipe 52 is arranged above the filler 51, and the spray pipe 52 is connected to the spray pump 54 through the second delivery pipeline 53. The spray pump 54 is connected to the water storage area 17. During operation, the spray pump 54 extracts the external circulating water from the water storage area 17, and after passing through the second delivery pipeline 53, sprays it onto the filler 51 through the spray pipe 52. At the same time, due to the suction of the induced draft fan 2, the first air inlet end 11 sucks in the external natural hot air, and the external natural air passes through the filler 51 with a honeycomb hole structure and contacts the sprayed external circulating water to achieve heat exchange, reducing the temperature of the external circulating water, thereby ensuring the heat exchange effect between the external circulating water and the internal circulating water.

[0052] In the present invention, by designing the spray cooling device 5 including the filler 51 with a honeycomb hole structure, the spray pipe 52 located above the filler 51, and the second delivery pipeline 53 connecting the spray pipe 52 and the spray pump 54, during specific operation, not only can the external circulating water in the water storage area 17 be sprayed onto the filler 51 to exchange heat with the external natural hot air, thereby reducing the temperature of the external circulating water; but also the filler 51 with a honeycomb hole structure can play a role in dust removal and filtration for the inhaled external natural hot air, and the sprayed external circulating water can also play a certain role in dust removal and filtration, so that dust and other impurities carried in the external natural air will not enter the air mixing area 13, thereby effectively reducing the scaling on the outer surface of the heat exchange tube bundle 3.

[0053] In some embodiments of the present invention, baffles 18 are provided between the cooling area 12, the air mixing area 13, and the heat exchange area 14 and the water storage area 17; a water collecting tank 61 and a clean water tank 62 are formed in the water storage area 17. Among them, the water collecting tank 61 is used to collect the external circulating water after spraying and cooling, and the clean water tank 62 is used to store the filtered external circulating water. Water inlet holes 181 are formed on the baffle 18 to connect the cooling area 12 and the heat exchange area 14 with the water collecting tank 61, so that the external circulating water sprayed onto the heat exchange area 14 and the external circulating water sprayed onto the cooling area 12 can be collected into the water collecting tank 61. The spraying device 4 is connected to the clean water tank 62, so that the spraying device 4 can extract the clean external circulating water from the clean water tank 62. The spray cooling device 5 is connected to the water collecting tank 61, so that the spray cooling device 5 can extract the external circulating water from the water collecting tank 61 for spray cooling.

[0054] Furthermore, the water collecting tank 61 and the clean water tank 62 are separated by an overflow plate 63, so that the external circulating water in the water collecting tank 61 and the clean water tank 62 will not be mixed together. A suspended matter filter screen 64 is provided on one side of the clean water tank 62 at the upper end of the overflow plate 63, and the height of the overflow plate 63 is lower than the height around the water collecting tank 61 and the clean water tank 62, so that the external circulating water will not flow to the outside of the water collecting tank 61 and the clean water tank 62, and it is ensured that the external circulating water in the water collecting tank 61 can overflow into the clean water tank 62.

[0055] In the present invention, a water collecting tank 61 and a purified water tank 62 are formed in the water storage area 17, the cooling area 12 and the heat exchange area 14 are both communicated with the water collecting tank 61, the spray cooling device 5 is communicated with the water collecting tank 61, the injection device 4 is communicated with the purified water tank 62, and a suspended matter filter screen 64 is arranged at the upper end of the overflow plate 63 between the water collecting tank 61 and the purified water tank 62. In the specific use process, on the one hand, the spray cooling device 5 can extract the external circulating water from the water collecting tank 61 for spray cooling, and the external circulating water after heat exchange in the heat exchange area 14 and the external circulating water after cooling in the cooling area 12 can both be collected into the water collecting tank 61. In this way, it can better realize the cooling of the used external circulating water to ensure the subsequent heat exchange effect, and can also make the used external circulating water form precipitation in the water collecting tank 61 to filter out impurities such as particulate matters in the external circulating water. On the other hand, the external circulating water after precipitation and cooling can enter the suspended matter filter screen 64 in an overflow manner and then enter the purified water tank 62 through the suspended matter filter screen 64. In this way, the water quality of the external circulating water extracted by the injection device 4 can be guaranteed, so as to ensure that after the external circulating water is sprayed onto the heat exchange tube bundle 3, the surface of the heat exchange tube bundle 3 is not easily fouled, and the heat exchange performance of the heat exchange tube bundle 3 can be guaranteed.

[0056] In some embodiments of the present invention, a water collector 7 is arranged at the second air inlet end 15 of the closed tower body 1. By arranging the water collector 7 at the second air inlet end 15, on the one hand, it can prevent the external circulating water sprayed by the injection device 4 from being splashed outside the closed tower body 1, thus avoiding waste of water resources. On the other hand, the water collector 7 can play a role in isolating the external environment, preventing impurities such as dust in the external environment from entering the closed tower body 1 through the second air inlet end 15 along with the external natural wind and having an adverse effect on the heat exchange tube bundle 3.

[0057] In the present invention, by arranging a filler 51 with a honeycomb hole structure in the cooling area 12 near the first air inlet end 11 and a water collector 7 at the second air inlet end 15, the contact between the external circulating water and the external environment can be effectively reduced, the natural evaporation amount of the external circulating water can be reduced, which can play a role in saving water, and it can also play a role in dust removal and filtration for the external natural hot air to reduce the pollution of the external circulating water by the external environment. At the same time, the external circulating water extracted by the injection device 4 is the external circulating water after precipitation treatment in the water collecting tank 61, filtration treatment by the suspended matter filter screen 64 and filtration treatment by the filtration device 45, which can effectively reduce the fouling of the heat exchange tube bundle 3. Especially when the external circulating water uses softened water, the concentration ratio can be effectively increased, the hard fouling of the heat exchange tube bundle 3 can be reduced, so as to extend the service life of the equipment and enable the equipment to maintain high-efficiency heat exchange performance without attenuation for a long time.

[0058] Embodiment Two

[0059] Please refer to Figures 1 to 4 As shown, a heat exchange method for a countercurrent evaporation cooling tower 100 of the present invention. The specific structure of the countercurrent evaporation cooling tower 100 and the technical effects that can be obtained are exactly the same as those in Embodiment 1. For the specific details, please refer to the detailed introduction in Embodiment 1 and will not be elaborated here. The heat exchange method includes the following steps:

[0060] The internal circulating water (i.e., high-temperature circulating water) is conveyed into the tube of the heat exchange tube bundle 3 through the circulating water inlet 31 at the lower end of the heat exchange tube bundle 3. The spraying device 4 is controlled to extract the external circulating water from the water storage area 17 and spray it outside the tube of the heat exchange tube bundle 3, so that the external circulating water forms a thin water film with a flow direction opposite to that of the internal circulating water on the outer side of the heat exchange tube bundle 3. At the same time, the induced draft fan 2 is controlled to draw the external natural wind into the closed tower body 1 through the first air inlet end 11 and the second air inlet end 15. The external natural wind drawn in from the second air inlet end 15 passes through the heat exchange tube bundle 3 in a cross-flow manner, so that the external natural wind and the external circulating water jointly conduct contact heat exchange with the outer side of the heat exchange tube bundle 3, thereby reducing the temperature of the internal circulating water. The external natural wind drawn in from the first air inlet end 11 passes through the spray cooling device 5 in a cross-flow manner, and the spray cooling device 5 is controlled to extract the external circulating water from the water storage area 17 for spraying, so that the external natural wind exchanges heat with the sprayed external circulating water, thereby reducing the temperature of the external circulating water. The two streams of external natural wind after heat exchange are mixed in the air mixing area 13 and discharged through the induced draft fan 2. The external circulating water after heat exchange flows into the water storage area 17 to realize the recycling of the external circulating water. The internal circulating water after heat exchange is output through the circulating water outlet 32 to supply the internal circulating water to other equipment for use.

[0061] In the present invention, the spraying device 4 is controlled to extract the external circulating water from the clean water tank 62 in the water storage area 17, that is, the spraying device 4 extracts the filtered and clean external circulating water from the clean water tank 62 to reduce the scaling on the outer surface of the heat exchange tube bundle 3. The spray cooling device 5 is controlled to extract the external circulating water from the collection tank 61 in the water storage area 17, and the external circulating water after heat exchange flows into the collection tank 61 in the water storage area 17. The external circulating water in the collection tank 61 enters the clean water tank 62 in an overflow manner.

[0062] Although the specific embodiments of the present invention have been described above, those skilled in the art of this technology should understand that the specific embodiments we described are illustrative rather than used to limit the scope of the present invention. Equivalent modifications and variations made by those skilled in the art in accordance with the spirit of the present invention should be covered by the scope protected by the claims of the present invention.

Claims

1. A counter-current evaporative cooling tower, characterized in that: It includes a closed tower body, an induced draft fan, a heat exchange tube bundle, an injection device and a spray cooling device; the closed tower body is provided with a first air inlet end, a cooling area, an air mixing area, a heat exchange area and a second air inlet end in sequence from one side to the other side, the closed tower body is provided with an air outlet end at a position corresponding to the air mixing area, a water storage area is formed below the cooling area, the air mixing area and the heat exchange area in the closed tower body, and the induced draft fan is arranged at the air outlet end; the heat exchange tube bundle is arranged in the heat exchange area along the vertical direction, a circulating water inlet is provided at the lower end of the heat exchange tube bundle, and a circulating water outlet is provided at the upper end of the heat exchange tube bundle; the injection device is arranged between the heat exchange tube bundle and the water storage area, and external circulating water is extracted from the water storage area through the injection device and sprayed onto the outer surface of the heat exchange tube bundle; the spray cooling device is arranged in the cooling area, and external circulating water is extracted from the water storage area through the spray cooling device for spray cooling.

2. A counter-flow evaporative cooling tower as claimed in claim 1, characterized in that: A plurality of heat exchange tube bundles are arranged from left to right in the heat exchange area, each heat exchange tube bundle includes a plurality of heat exchange plate tubes arranged from front to back, and the heat exchange plate tubes on each heat exchange tube bundle are aligned with each other.

3. A counter-flow evaporative cooling tower as claimed in claim 2, characterized in that: The injection device includes a nozzle, a high-pressure injection pump, a flow diversion pipeline and a first delivery pipeline; A plurality of shunt pipes are arranged from bottom to top between two adjacent heat exchange plate tubes and on the front and rear sides of the heat exchange tube bundle, and a plurality of nozzles are arranged on each shunt pipe, and the nozzles of the nozzles face the outer surface of the heat exchange plate tube; each shunt pipe is connected to the high-pressure jet pump through the first delivery pipeline, the high-pressure jet pump is connected to the water storage area, and a filtering device is provided at the input end of the high-pressure jet pump.

4. A counter-flow evaporative cooling tower as claimed in claim 3, characterized in that: The nozzle is a wide-angle fan-shaped nozzle.

5. A counter-flow evaporative cooling tower as claimed in claim 1, characterized in that: The spray cooling device comprises a filler with a honeycomb hole structure, a spray pipe, a second delivery pipeline and a spray pump; The filler is arranged in the cooling area, the spray pipe is arranged above the filler, and the spray pipe is connected with the spray pump through the second delivery pipeline, and the spray pump is connected with the water storage area.

6. A counter-flow evaporative cooling tower as claimed in claim 1, characterized in that: A baffle is arranged between the cooling area, the air mixing area, the heat exchange area and the water storage area; a water collecting tank and a clean water tank are formed in the water storage area, and a water inlet hole is opened on the baffle to connect the cooling area and the heat exchange area with the water collecting tank, the injection device is connected with the clean water tank, and the spray cooling device is connected with the water collecting tank.

7. A counter-flow evaporative cooling tower as claimed in claim 1, characterized in that: The water collecting tank is separated from the clean water tank by an overflow plate, a suspended matter filter is arranged on the upper end of the overflow plate at one side of the clean water tank, and the height of the overflow plate is lower than the height around the water collecting tank and the clean water tank.

8. A counter-flow evaporative cooling tower as claimed in claim 1, characterized in that: The second air inlet end of the closed tower body is provided with a water collector.

9. A heat exchange method based on a counter-flow evaporative cooling tower according to any one of claims 1 to 8, characterized in that: The steps include: The inner circulating water is transported to the tubes of the heat exchange tube bundle through the circulating water inlet at the lower end of the heat exchange tube bundle, and the spray device is controlled to extract the outer circulating water from the water storage area and spray it to the outside of the heat exchange tube bundle, so that the outer circulating water forms a thin water film on the outside of the heat exchange tube bundle in the opposite direction to the flow direction of the inner circulating water; at the same time, the induced draft fan is controlled to draw the external natural wind into the closed tower body through the first air inlet end and the second air inlet end, and the external natural wind drawn from the second air inlet end passes through the heat exchange tube bundle in a cross flow manner, so that the external natural wind and the external circulating water are in contact with the outside of the heat exchange tube bundle for heat exchange; the external natural wind drawn from the first air inlet end passes through the spray cooling device in a cross flow manner, and the spray cooling device is controlled to extract the external circulating water from the water storage area for spraying, so that the external natural wind exchanges heat with the sprayed external circulating water; the two external natural winds after heat exchange are mixed in the air mixing area and discharged through the induced draft fan, the external circulating water after heat exchange flows into the water storage area, and the internal circulating water after heat exchange is output through the circulating water outlet.

10. A heat exchange method for a counter-flow evaporative cooling tower as claimed in claim 9, characterized in that: The injection device is controlled to extract external circulation water from the clean water tank in the water storage area, and the spray cooling device is controlled to extract external circulation water from the water collecting tank in the water storage area, and the external circulation water after heat exchange flows into the water collecting tank in the water storage area, and the external circulation water in the water collecting tank enters the clean water tank in an overflow manner.

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