Evaporation precooling type cooling tower water saving system and method

Abstract

The invention provides an evaporation precooling type cooling tower water saving system and method, and relates to the technical field of cooling towers, the evaporation precooling type cooling tower water saving system comprises an evaporator, the evaporator comprises a tank body and a heat exchange pipe, a heat exchange cavity is formed in the tank body, the heat exchange pipe is used for being connected with a water source to be cooled, and a heat exchange section extending into the heat exchange cavity is arranged between the two ends of the heat exchange pipe; the condenser comprises a condensation pipe and a fan, the condensation pipe is of a snakelike bent structure, one end of the condensation pipe is connected to the top of the heat exchange cavity through an ascending pipe, the other end of the condensation pipe is connected to the bottom of the heat exchange cavity through a descending pipe, and the fan is installed at the position of the snakelike bent structure of the condensation pipe. By arranging a system composed of the evaporator, the condenser and other components, cooling water passes through the heat exchange section to exchange heat with the circulating working medium in the tank body before entering the cooling tower, evaporation precooling is achieved, the effect of reducing the heat load of the cooling water entering the tower is achieved, therefore, evaporation loss can be reduced, and finally water saving is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of cooling towers, and in particular to a water-saving system and method for an evaporative precooling cooling tower. Background Art

[0002] In a wet-cooled thermal power plant, the main water consumption includes the circulating water cooling system, chemical desalted water system, ash water system, domestic fire water system, desulfurization water system, etc. Among them, the circulating water cooling process is as follows: in a thermal power plant, water is heated into high-pressure steam in the boiler, and then enters the steam turbine to drive the steam turbine to work and make the generator generate electricity. The exhaust gas after the steam turbine works is discharged into the condenser to exchange heat with the cooling water and condense into water, and then pumped back to the boiler for recycling. The cooling water carrying waste heat transfers heat and mass with the air in the cooling tower, so that the waste heat is transferred to the air and finally dissipated into the atmosphere. After the water cooled in the cooling tower becomes low-temperature water, the water pump sends it back to the condenser for recycling.

[0003] As an important auxiliary production equipment in thermal power plants, wet cooling towers are an indispensable and important device for wet cooling. In the process of heat and mass transfer between cooling water and air in the tower, water losses will occur, namely evaporation loss, wind loss and sewage loss. These three losses account for 65% to 75% of the water consumption of thermal power plants, of which evaporation loss accounts for the vast majority. Evaporation loss is due to the fact that in the process of heat exchange between cooling water and air in the tower, water molecules continuously diffuse into the air in the form of evaporation and heat dissipation, and the water absorbs heat to become water vapor. The water vapor is discharged from the top of the cooling tower with the air, thereby taking away a large amount of heat. In a wet cooling tower, the reduction of cooling water volume and water inlet temperature will lead to a reduction in evaporation loss. The present invention defines the heat load of cooling water as Q=C w Wt1(C w is the specific heat capacity of water, W is the cooling water volume, and t1 is the cooling water temperature), then the reduction in the inlet water temperature and the reduction in the inlet water volume can be unified with the reduction in the inlet cooling water heat load. When the inlet heat load is reduced, the evaporation loss is reduced.

[0004] A Chinese patent (publication number CN114166040B, publication date 20230922) discloses a cooling and energy-saving device for a cooling tower and a wet cooling tower, including a water collecting tank and an air precooling device. The water collecting tank closes the inner wall of the tower tube, and the air precooling device passes through the bottom of the water collecting tank. The lower inlet of the air precooling device is connected to the new air entering the lower part of the tower tube, and the top outlet is provided with a hood for shielding water droplets. The air precooling device is located in the rain area under the cooling tower filler. The air precooling device is used to cool the ambient air absolutely, which can further reduce the outlet water temperature to below the wet-bulb temperature of the ambient air, or even close to the dew point temperature, thereby reducing the outlet cooling water temperature. However, it is a structural adjustment for the wet cooling tower, and the traditional water collecting tank bottom of the air precooling device is inconvenient to be constructed and improved for the wet cooling tower that has been built, and the heat load of the cooling water entering the tower has not been effectively reduced. Summary of the invention

[0005] The purpose of the present invention is to provide an evaporative precooling cooling tower water-saving system and method in view of the defects of the prior art. Before the cooling water enters the cooling tower, it first passes through a heat exchange section to exchange heat with a circulating working medium in a tank body to achieve evaporative precooling, reduce the heat load of the cooling water entering the tower, thereby reducing evaporation losses and achieving water saving.

[0006] The first object of the present invention is to provide an evaporative precooling cooling tower water saving system, which adopts the following scheme:

[0007] The evaporator comprises a tank body and a heat exchange tube, wherein a heat exchange cavity is formed in the tank body, the heat exchange tube is used to connect to a water source to be cooled, and a heat exchange section is provided between both ends of the heat exchange tube and extends into the heat exchange cavity;

[0008] The condenser includes a condenser tube and a fan. The condenser tube has a serpentine structure. One end of the condenser tube is connected to the top of the heat exchange chamber through a riser, and the other end is connected to the bottom of the heat exchange chamber through a downcomer. The fan is installed at the serpentine structure position of the condenser tube.

[0009] Furthermore, the serpentine curved structure of the condenser tube is composed of a plurality of straight tube sections and curved sections that are distributed at intervals, and the straight tube sections are connected in sequence through the curved sections to form a serpentine distribution.

[0010] Furthermore, the straight pipe section is distributed obliquely, and along the flow direction of the circulating working medium inside the condenser tube, the end of the straight pipe section entering the circulating working medium is higher than the end of the straight pipe section discharging the circulating working medium.

[0011] Furthermore, fins are connected to the tube wall of the condenser tube, and the fins are distributed at intervals along the axial direction of the condenser tube.

[0012] Furthermore, the heat exchange section is a bent tube, and the heat exchange tube is immersed in the circulating working medium contained in the tank body.

[0013] Furthermore, the heat exchange section is U-shaped, the heat exchange tube is fixed to the tank body, and the end of the heat exchange tube outside the tank body is connected to the water source to be cooled.

[0014] Furthermore, the heat exchange tubes are provided in plurality, distributed at intervals and respectively installed on the tank body.

[0015] Furthermore, the tank body axis is horizontally distributed, and the heat exchange section extends and distributes in the heat exchange cavity along the tank body axis.

[0016] The second object of the present invention is to provide a working method of the evaporative precooling cooling tower water-saving system as described in the first object, comprising:

[0017] The water source to be cooled is connected to one end of the heat exchange tube through a water supply pump, and the other end of the heat exchange tube is connected to the cooling tower through a water pipe, so that the cooling water passes through the heat exchange section of the heat exchange tube;

[0018] The cooling water exchanges heat with the circulating medium in the heat exchange chamber in the heat exchange section. The circulating medium around the heat exchange tube evaporates quickly to form a gas circulating medium, which takes away the heat of the cooling water, realizes evaporative precooling of the cooling water, and then supplies it to the cooling tower.

[0019] The gas circulating medium enters the condensing tube of the condenser through the riser. The heat of the gas circulating medium is transferred to the air under the action of the fan. The gas circulating medium is liquefied into liquid circulating medium and flows back to the heat exchange chamber through the downcomer to realize the circulation of the circulating medium.

[0020] Furthermore, the height difference between the liquid circulating medium in the downcomer and the liquid circulating medium in the evaporator provides a gravity driving force for the circulation of the circulating medium.

[0021] Compared with the prior art, the present invention has the following advantages and positive effects:

[0022] In view of the current problems of high heat load of cooling water entering the tower and large evaporation loss, a system consisting of components such as evaporator and condenser is set up. The cooling water passes through the heat exchange section and exchanges heat with the circulating working fluid in the tank before entering the cooling tower, realizing evaporative pre-cooling, achieving the effect of reducing the heat load of cooling water entering the tower, thereby reducing evaporation loss and ultimately achieving water saving.

[0023] Combined with the temperature range of the circulating cooling water in the power plant and the pressure range of the system, the evaporative precooling system adopts a circulating medium. When there is no flow inside, the heavier liquid circulating medium stays at the bottom of the evaporator, while the gaseous circulating medium fills the remaining space and maintains a saturated state in the system. When the cooling water of a certain temperature enters the heat exchange section in the evaporator located below, the circulating medium around the heat exchange tube evaporates rapidly, taking away the heat of the cooling water, thereby achieving evaporative precooling of the cooling water. The gaseous circulating medium enters the condenser above through the riser under the action of the density difference, and its heat is transferred to the air under the action of the fan, condensed back into liquid, and collected in the vertical downcomer connecting the condenser outlet and the evaporator inlet. The height difference between the liquid working medium in the downcomer and the liquid working medium in the evaporator provides a gravity driving force for the circulation of the working medium. The working medium flows from the evaporator to the condenser in a natural circulation and automatic adjustment manner without any pump or compressor. The heat of the circulating cooling water is first transferred to the circulating working fluid and then to the air on the condensing side. In this process, only the fan on the condensing side consumes energy, which improves the average energy efficiency ratio and has obvious energy-saving effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0025] Figure 1 Schematic diagram of the evaporative precooling cooling tower water saving system in Examples 1 and 2 of the present invention.

[0026] Figure 2 It is a front view of the evaporator in Examples 1 and 2 of the present invention.

[0027] Figure 3 1 is a top view of the evaporator in Examples 1 and 2 of the present invention.

[0028] Figure 4 It is a side view of the evaporator in Examples 1 and 2 of the present invention.

[0029] Figure 5 Schematic diagram of the distribution structure of the evaporator and heat exchange tubes in Examples 1 and 2 of the present invention.

[0030] Figure 6 It is a front view of the condenser in Examples 1 and 2 of the present invention.

[0031] Figure 7 1 is a top view of the condenser in Examples 1 and 2 of the present invention.

[0032] Figure 8 It is a side view of the condenser in Examples 1 and 2 of the present invention.

[0033] Among them, 1. Cooling tower fan; 2. Water eliminator; 3. Spray assembly; 4. Filler; 5. Water collection tank; 6. Return water pump; 7. Constant temperature water tank; 8. Valve; 9. Water feed pump; 10. Evaporator; 11. Downcomer; 12. Riser; 13. Condenser. DETAILED DESCRIPTION

[0034] Example 1

[0035] In a typical embodiment of the present invention, Figure 1-Figure 8 As shown, an evaporative precooling cooling tower water saving system is provided.

[0036] For the wet cooling tower that has been built, it is inconvenient to construct the improved air precooling device through the bottom of the water collection pool 5, and it fails to effectively reduce the heat load of the cooling water entering the tower. Based on this, this embodiment provides an evaporative precooling cooling tower water-saving system, which is composed of a system composed of components such as an evaporator 10 and a condenser 13, so that the cooling water passes through the heat exchange section and exchanges heat with the circulating working medium in the tank before entering the cooling tower, thereby solving the problem that the heat load of the cooling water entering the tower cannot be effectively reduced, thereby reducing evaporation losses and achieving the purpose of saving water.

[0037] like Figure 1 As shown, the evaporative precooling cooling tower water-saving system mainly includes an evaporator 10 and a condenser 13. The evaporator 10 includes a tank body and a heat exchange tube. The tank body is used as a container for accommodating the circulating working fluid. A heat exchange cavity is formed in the tank body. The heat exchange tube is used to connect to the water source to be cooled. A heat exchange section that probes into the heat exchange cavity is provided between the two ends of the heat exchange tube. When the cooling water supplied by the water source to be cooled enters the heat exchange section, it can exchange heat with the circulating working fluid in the heat exchange cavity. During the evaporation of the circulating working fluid, the heat of the cooling water is taken away, thereby realizing the precooling of the cooling water. The heat absorbed by the circulating working fluid exchanges heat with the outside air at the position of the condenser 13 to achieve cooling. The cooling water can exchange heat with the circulating working fluid in the tank body, which is a key link in realizing evaporative precooling and reducing the heat load of the cooling water entering the tower. The heat of the cooling water can be transferred to the circulating working fluid, thereby starting the entire precooling process.

[0038] The condenser 13 includes a condenser tube and a fan. The condenser tube has a serpentine structure. One end of the condenser tube is connected to the top of the heat exchange chamber through the riser tube 12, so that the circulating working fluid evaporated in the heat exchange chamber can enter the condenser 13 through the riser tube 12. The other end is connected to the bottom of the heat exchange chamber through the downcomer 11, so that the circulating working fluid after heat exchange in the condenser 13 can flow back to the heat exchange chamber of the tank body. The fan is installed at the serpentine structure position of the condenser tube. The fan promotes airflow through the condenser tube to exchange heat with the circulating working fluid in the condenser tube.

[0039] The condenser tube has a serpentine curved structure, which increases the area for heat exchange with the outside world. One end of the condenser tube is connected to the top of the heat exchange chamber through the riser 12, and the other end is connected to the bottom of the heat exchange chamber through the downcomer 11, which can form a circulation passage for the circulating medium between the heat exchange chamber of the evaporator 10 and the condenser tube of the condenser 13, facilitating the subsequent heat transfer and the change of the state of the circulating medium (from gas to liquid, etc.).

[0040] The function of the fan is to accelerate the flow of air around the condenser tube, so that the circulating medium can better dissipate heat to the external environment when passing through the serpentine condenser tube, so that the gaseous circulating medium can condense into liquid more quickly, thereby ensuring the continuous and efficient circulation of the entire circulating medium and the heat exchange process, assisting the evaporation precooling process of the cooling water, and achieving the effects of reducing the heat load entering the tower and saving water.

[0041] During operation, the circulating fluid can be R134a or other fluids that meet the heat exchange requirements. Figure 1 As shown, before the circulating cooling water enters the cooling tower, it is first passed into the evaporative precooling cooling tower water-saving system in this embodiment for precooling to reduce its heat load, thereby reducing the evaporation loss generated when entering the cooling tower. The evaporative precooling cooling tower water-saving system is upstream of the cooling tower. Combined with the temperature range of the circulating cooling water in the power plant and the pressure range of the system, the evaporative precooling cooling tower water-saving system in this embodiment uses R134a as a circulating working fluid. When there is no flow inside, the heavier liquid R134a stays at the bottom of the evaporator 10, while the gaseous R134a fills the remaining space and maintains a saturated state in the system.

[0042] When cooling water of a certain temperature enters the heat exchange tube of the evaporator 10 located at the lower position, the R134a around the heat exchange tube evaporates rapidly, taking away the heat of the cooling water, thereby achieving the effect of evaporative precooling of the cooling water. The gaseous R134a enters the condenser 13 above through the riser 12 under the action of the density difference, and its heat is transferred to the air under the action of the fan, condensed back into liquid, and collected in the vertical downcomer 11 connecting the outlet of the condenser 13 and the inlet of the evaporator 10. The height difference between the liquid circulating medium in the downcomer 11 and the liquid circulating medium in the evaporator 10 provides a gravity driving force for the circulation of the circulating medium.

[0043] The circulating medium flows from the evaporator 10 to the condenser 13 in a natural circulation and automatic adjustment mode without any pump or compressor. The heat of the circulating cooling water is first transferred to R134a and then to the air on the condensing side. In this process, only the fan on the condensing side consumes energy, and the average energy efficiency ratio exceeds 30, with obvious energy saving effect.

[0044] Combined with environmental conditions, taking into account the ratio between the size of the thermal driving force and the water and energy costs, the water distribution of the evaporative precooling cooling tower water-saving system and the wind speed of the condenser 13 fan are adjusted to ensure the economic balance between water saving and fan energy consumption. The evaporative precooling cooling tower water-saving system enhances the heat exchange effect by phase change heat transfer. Therefore, the wet cooling tower is coupled with the evaporative precooling cooling tower water-saving system in this embodiment to achieve water saving. According to the number of installed evaporative precooling cooling tower water-saving systems, it can handle the entire heat load in a colder environment, eliminating the dense fog and icing problems generated by the cooling tower, and improving the flexibility of the heat dissipation system.

[0045] like Figure 6 , Figure 7 and Figure 8 As shown, the serpentine curved structure of the condenser tube is composed of a plurality of straight tube sections and curved sections that are distributed at intervals, and the straight tube sections are connected in sequence through the curved sections to form a serpentine distribution. By designing the condenser tube to be a serpentine structure composed of a plurality of straight tube sections and curved sections, on the one hand, the length of the condenser tube can be increased as much as possible within a limited space, thereby increasing its contact area with the outside air, which is conducive to better heat dissipation of the circulating medium to the outside when flowing through the condenser tube, and accelerating the condensation process of the gaseous circulating medium; on the other hand, the interval distribution design can make the air flow more smoothly between the parts, avoiding the occurrence of local heat accumulation, poor air circulation, and other situations that affect the condensation effect.

[0046] It helps to improve the working efficiency of the condenser 13, ensure that the circulating working fluid can be transformed from gas to liquid in time, maintain the stability of the circulating working fluid in the entire evaporative precooling cooling tower water-saving system, and enable the evaporative precooling process of the cooling water at the evaporator 10 to be carried out continuously and efficiently, thereby better reducing the heat load entering the tower and achieving the purpose of saving water.

[0047] Specifically, the straight pipe section is tilted, and along the flow direction of the circulating medium inside the condenser, the end of the straight pipe section that enters the circulating medium is higher than the end that discharges the circulating medium. The tilted distribution design conforms to the flow characteristics of the circulating medium and the principle of gravity. The gaseous circulating medium will gradually liquefy during the condensation process. The tilted setting allows the liquefied circulating medium to flow more smoothly along the straight pipe section to a lower place under the action of gravity, avoiding the accumulation of liquid medium in the tube and obstruction of subsequent gaseous medium flow, ensuring the continuous and orderly flow of the circulating medium in the condenser, and improving the efficiency and stability of condensation.

[0048] In the condenser 13, along the flow direction of the circulating medium in the tube, the straight tube section is tilted downward by 5°. This ensures that the condenser 13 can efficiently convert the gaseous circulating medium into liquid, so that the entire circulating medium circulation loop can operate stably, ensuring that the heat exchange process at the evaporator 10 is not affected by problems such as poor reflux of the circulating medium, maintaining the normal operation of the entire water-saving system, and achieving stable evaporative precooling, reduced inlet heat load, and water-saving effects.

[0049] Fins are connected to the tube wall of the condenser tube. The fins are spaced apart along the axis of the condenser tube. The shape of the fins can be configured according to demand, such as triangle, square, rectangle, etc. The setting of the fins further increases the heat exchange area between the condenser tube and the outside air, because the fins themselves can exchange heat with the air, which is equivalent to expanding more heat dissipation surfaces on the basis of the original condenser tube. At the same time, the spaced fins can cause turbulence in the air when it flows through, enhance the heat exchange effect between the air and the condenser tube, accelerate the transfer of heat from the circulating medium to the air, and improve the condensation efficiency of the condenser tube.

[0050] It is understandable that the length of the straight tube section of the condenser tube can be 1.2m, the condenser tube can be supported by copper processing, and the fins can be made of aluminum. The heat dissipation and condensation capacity of the condenser 13 is significantly improved, so that the circulating medium can complete the transformation from gas to liquid faster, which helps to speed up the circulation speed of the circulating medium in the whole system, thereby making the heat exchange process in the evaporator 10 more efficient, enhancing the effect of cooling water evaporation precooling, and more conducive to reducing the heat load entering the tower and achieving the overall goal of water saving.

[0051] In this embodiment, Figure 6 As shown, during the experimental simulation, the condenser tube has an outer diameter of 18 mm, an inner diameter of 15 cm, 11 tube rows, 22 straight tube sections in total, the fin outer diameter is 0.35 mm, the diameter spacing is 3 mm, and the thickness is 1 mm; the curved section is a 180° elbow, with a total of 21; the fan has a diameter of 300 mm, a total pressure of 59 Pa, an air volume of 1750 m3, and there are two fans in total.

[0052] The partition serves to support the heat exchange tubes and the fan. The back partition is 124 cm long and 80 cm wide, with two circular holes with a diameter of 300 mm in the middle for installing the two fans. The bracket is composed of four circular tubes with a diameter of 25 mm and a height of 1 m, which are respectively installed on the four corners of the bottom partition to support the condenser 13.

[0053] like Figure 2 , Figure 3 , Figure 4 and Figure 5As shown, the heat exchange section is a curved tube, and the heat exchange tube is immersed in the circulating working fluid contained in the tank body. In this embodiment, the heat exchange section is U-shaped, and the heat exchange tube is fixed to the tank body. The end of the heat exchange tube outside the tank body is connected to the water source to be cooled. The heat exchange section adopts a curved tube, especially a U-shaped structure, which increases the contact area between the heat exchange tube and the circulating working fluid in the tank body, so that the water to be cooled can more fully exchange heat with the circulating working fluid when flowing through the heat exchange section, improve the heat exchange efficiency, and ensure that the cooling water can better achieve evaporative precooling. At the same time, the heat exchange tube is fixed to the tank body and immersed in the circulating working fluid, which ensures the stability and continuity of the heat exchange, and the end outside the tank body is conveniently connected to the water source to be cooled, so that the entire cooling water precooling process can be carried out smoothly, which improves the heat exchange performance of the evaporator 10, and lays the foundation for the entire water-saving system to reduce the heat load entering the tower, thereby helping to reduce evaporation losses and achieve the ultimate goal of water saving.

[0054] There are multiple heat exchange tubes, which are spaced and installed on the tank body respectively. The cooling water in multiple water flow channels can be pre-cooled at the same time, which increases the cooling water flow rate that can be pre-cooled per unit time and improves the processing capacity of the entire system. In addition, the spaced distribution can make the circulating working fluid around each heat exchange tube relatively evenly distributed, avoiding the situation where the local circulating working fluid temperature is too high or too low due to the centralized setting, which affects the heat exchange effect, and ensures that each heat exchange tube can efficiently exchange heat with the circulating working fluid. The overall pre-cooling efficiency and processing scale of the evaporator 10 for cooling water are improved, so that more cooling water can achieve better evaporative pre-cooling before entering the cooling tower, more effectively reducing the heat load entering the tower, thereby reducing evaporation losses to a greater extent and better achieving the goal of water saving.

[0055] In this embodiment, the heat exchange tube is fixed by the partitions at both ends of the tank body of the evaporator 10. When conducting the experimental simulation, the heat exchange tube is located outside the tank body and extends 10 cm. The heat exchange tube is a stainless steel round tube. The base supports the evaporator 10 and has a height of 25 cm. The diameter of the two U-shaped tubes is 1 cm, the spacing is 16 cm, the lower end is the water inlet pipe, the upper end is the water outlet pipe, and the upper and lower ends are 5 cm apart.

[0056] The tank axis is horizontally distributed, and the heat exchange section extends and distributes in the heat exchange cavity along the tank axis. The horizontal distribution of the tank axis facilitates the installation and layout of the entire system, making the connection and operation of each component more in line with conventional engineering design and operating habits. The heat exchange section extends and distributes along the tank axis, which can make the heat exchange section have a more reasonable layout in the heat exchange cavity, fully utilize the space in the tank, ensure that the circulating working fluid at different positions can have a good heat exchange with the heat exchange section, and improve the heat exchange uniformity and efficiency in the entire evaporator 10.

[0057] The riser 12 and the downcomer 11 are both composed of circular tubes. The circulating working medium steam enters the condenser 13 from the top of the evaporator 10 through the riser 12, and returns to the evaporator 10 from the bottom of the condenser 13 through the downcomer 11, forming a cycle.

[0058] The evaporative precooling cooling tower water-saving system in this embodiment is connected to the wet cooling tower, and also includes a constant temperature water tank 7, a return water pump 6, a feed water pump 9, and a valve 8. The water inlet of the return water pump 6 is connected to the water collection tank 5 of the cooling tower through a pipeline, and the water outlet is connected to the constant temperature water tank 7. The water inlet of the feed water pump 9 is connected to the constant temperature water tank 7, and the water outlet is divided into two ways, one way is connected to the evaporative precooling cooling tower water-saving system, and the other way is connected to the spray assembly 3 of the cooling tower.

[0059] A cooling tower fan 1 is provided at the top of the cooling tower, and a dehumidifier 2, a spray assembly 3, a filler 4 and a water collection tank 5 are provided inside the cooling tower from top to bottom. The heating rod in the constant temperature water tank 7 heats the cooling water, and the water tank body is added with insulation material to maintain the constant temperature of the cooling water after heating to the specified temperature; when conducting the experimental simulation, the frame size of the cooling tower body is 0.7m×0.7m×1.8m, the tower wall is made of transparent acrylic glass plate, the model tower is single-sided air intake, the bottom air inlet height is 0.35m, the experimental filler 4 thickness is 1m, the top fan diameter is 0.6m, the rated air volume is 10400m3 / h, and the rated total pressure is 180Pa. In order to reduce the loss of dripping water, a dehumidifier 2 is installed between the fan and the spray device.

[0060] Example 2

[0061] In another typical embodiment of the present invention, Figure 1-Figure 8 As shown, a working method of an evaporative precooling cooling tower water-saving system is provided, using the evaporative precooling cooling tower water-saving system as in Example 1.

[0062] A working method of an evaporative precooling cooling tower water-saving system, comprising:

[0063] The water source to be cooled is connected to one end of the heat exchange tube through the water supply pump 9, and the other end of the heat exchange tube is connected to the cooling tower through the water pipe, so that the cooling water passes through the heat exchange section of the heat exchange tube;

[0064] The cooling water exchanges heat with the circulating medium in the heat exchange chamber in the heat exchange section. The circulating medium around the heat exchange tube evaporates quickly to form a gas circulating medium, which takes away the heat of the cooling water, realizes evaporative precooling of the cooling water, and then supplies it to the cooling tower.

[0065] The gas circulating medium enters the condensing tube of the condenser 13 through the riser 12. The heat of the gas circulating medium is transferred to the air under the action of the fan. The gas circulating medium is liquefied into liquid circulating medium and flows back to the heat exchange chamber through the downcomer 11 to realize the circulation of the circulating medium.

[0066] The height difference between the liquid circulating medium in the downcomer 11 and the liquid circulating medium in the evaporator 10 provides a gravity driving force for the circulation of the circulating medium.

[0067] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An evaporative precooling cooling tower water-saving system, characterized in that: include: The evaporator comprises a tank body and a heat exchange tube, wherein a heat exchange cavity is formed in the tank body, the heat exchange tube is used to connect to a water source to be cooled, and a heat exchange section is provided between both ends of the heat exchange tube and extends into the heat exchange cavity; The condenser includes a condenser tube and a fan. The condenser tube has a serpentine structure. One end of the condenser tube is connected to the top of the heat exchange chamber through a riser, and the other end is connected to the bottom of the heat exchange chamber through a downcomer. The fan is installed at the serpentine structure position of the condenser tube.

2. The evaporative precooling cooling tower water-saving system according to claim 1, characterized in that: The serpentine bending structure of the condenser tube is composed of a plurality of straight tube sections and curved sections that are distributed at intervals, and the straight tube sections are connected in sequence through the curved sections to form a serpentine distribution.

3. The evaporative precooling cooling tower water-saving system according to claim 2, characterized in that: The straight pipe section is distributed obliquely, and along the flow direction of the circulating working medium inside the condenser tube, the end of the straight pipe section entering the circulating working medium is higher than the end of the straight pipe section discharging the circulating working medium.

4. The evaporative precooling cooling tower water-saving system according to claim 1, 2 or 3, characterized in that: The tube wall of the condenser tube is connected with fins, and the fins are distributed at intervals along the axial direction of the condenser tube.

5. The evaporative precooling cooling tower water-saving system according to claim 1, characterized in that: The heat exchange section is a bent tube, and the heat exchange tube is immersed in the circulating working medium contained in the tank body.

6. The evaporative precooling cooling tower water-saving system according to claim 5, characterized in that: The heat exchange section is U-shaped, the heat exchange tube is fixed to the tank body, and the end of the heat exchange tube outside the tank body is connected to the water source to be cooled.

7. The evaporative precooling cooling tower water-saving system according to claim 5 or 6, characterized in that: The heat exchange tubes are provided in plurality, distributed at intervals and respectively installed on the tank body.

8. The evaporative precooling cooling tower water-saving system according to claim 7, characterized in that: The axis of the tank body is horizontally distributed, and the heat exchange section extends and distributes in the heat exchange cavity along the axis of the tank body.

9. A working method of an evaporative precooling cooling tower water-saving system, comprising: constructing an evaporative precooling cooling tower water-saving system as claimed in any one of claims 1 to 8, characterized in that: include: The water source to be cooled is connected to one end of the heat exchange tube through a water supply pump, and the other end of the heat exchange tube is connected to the cooling tower through a water pipe, so that the cooling water passes through the heat exchange section of the heat exchange tube; The cooling water exchanges heat with the circulating medium in the heat exchange chamber in the heat exchange section. The circulating medium around the heat exchange tube evaporates quickly to form a gas circulating medium, which takes away the heat of the cooling water, realizes evaporative precooling of the cooling water, and then supplies it to the cooling tower. The gas circulating medium enters the condensing tube of the condenser through the riser. The heat of the gas circulating medium is transferred to the air under the action of the fan. The gas circulating medium is liquefied into liquid circulating medium and flows back to the heat exchange chamber through the downcomer to realize the circulation of the circulating medium.

10. The working method of the evaporative precooling cooling tower water saving system according to claim 9, characterized in that: The height difference between the liquid circulating medium in the downcomer and the liquid circulating medium in the evaporator provides a gravity driving force for the circulation of the circulating medium.

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