Steam-water separation and defogging device for cooling tower

Abstract

The utility model belongs to the technical field of cooling towers, and provides a steam-water separation and defogging device for a cooling tower, which is arranged at the top of the cooling tower and comprises an air collecting cover arranged at an air outlet of the cooling tower, a water collecting and defogging channel arranged at an air outlet of the air collecting cover, and a condenser and an air cooler which are sequentially arranged in the water collecting and defogging channel. The tail end of the water collecting and mist expelling channel is provided with an air inducing barrel which is vertically installed, and an air outlet of the air inducing barrel is formed in the top end of the air inducing barrel. The device is arranged at the air outlet of the existing cooling tower and has small influence on the operation of the existing cooling tower, so that the water collection rate of evaporated water vapor of the cooling tower is greatly improved, and meanwhile, the device can efficiently eliminate mist and has an environment-friendly function.

Description

Technical Field

[0001] This utility model belongs to the field of cooling tower technology, and in particular relates to a steam-water separation and demisting device for cooling towers. Background Technology

[0002] Cooling towers are heat exchange devices widely used in industrial and building sectors. For example, in thermal power plants, cooling towers condense the high-temperature steam discharged from turbines into water, maintaining the efficient operation of generator units; in chemical production, they are used to control reactor temperatures and prevent equipment overheating; and in commercial buildings, cooling towers provide cooling water to central air conditioning systems, ensuring a comfortable indoor environment. Their core functions are twofold: first, through the principle of evaporative cooling (partial water evaporation carries away a large amount of heat), they reduce the temperature of circulating water to within the range required by the process; second, they enable the recycling of water resources, reducing industrial water consumption.

[0003] Cooling towers are classified into natural ventilation cooling towers and mechanical ventilation cooling towers according to their ventilation methods. Natural ventilation cooling towers rely on the difference in air density to form natural convection. They are commonly found in large power plants and have the characteristics of low operating costs and simple maintenance, but the initial construction cost is relatively high. Mechanical ventilation cooling towers, on the other hand, use fans to force ventilation. They are suitable for small and medium-sized systems with limited space. They have high cooling efficiency but consume more energy.

[0004] Typically, mechanical ventilation cooling towers have fans installed at the air outlet of the air duct at the top of the cooling tower to directly discharge the humid and hot saturated gas generated inside the tower. As a result, a large amount of water vapor in the humid and hot saturated gas is also directly discharged into the atmosphere, causing a waste of water resources, as well as generating a large amount of rain and fog, polluting the environment, and affecting visibility.

[0005] Some existing water-saving and defogging technologies employ a solution that involves installing a water-absorbing device and a dehydration device. The water-absorbing device, such as absorbent cotton, absorbs moisture from the hot and humid gas, and the dehydration device then removes the absorbed moisture. However, this technology has low water absorption efficiency, and the moisture content of the final discharged gas is still relatively high, resulting in an unsatisfactory effect in eliminating plumes and fog.

[0006] Therefore, there is an urgent need for a steam-water separation and demisting device for cooling towers to improve water collection efficiency and demisting effect. Summary of the Invention

[0007] To address the problems existing in the prior art, the purpose of this utility model is to provide a steam-water separation and demisting device for cooling towers, which better improves the water collection rate and demisting rate of evaporated water vapor in cooling towers.

[0008] To achieve the above objectives, this utility model is implemented through the following technical solution:

[0009] A steam-water separation and demisting device for a cooling tower is installed at the top of the cooling tower. It includes an air collecting hood installed at the air outlet of the cooling tower, a water collecting and demisting channel installed at the air outlet of the air collecting hood, a condenser and an air cooler installed in sequence in the water collecting and demisting channel, and an exhaust duct installed at the end of the water collecting and demisting channel. The exhaust duct is installed vertically, and the air outlet of the exhaust duct is located at the top of the exhaust duct.

[0010] Furthermore, the condenser includes at least a condenser tube disposed within the water collection and mist removal channel, with both ends of the condenser tube connected to a refrigeration unit, and the refrigeration unit supplying refrigerant to the condenser tube.

[0011] Furthermore, the condenser tubes are cold storage coils, with each condenser tube set perpendicular to the gas flow direction in the water collection and mist driving channel. Multiple condenser tubes are set along the gas flow direction, and adjacent condenser tubes are staggered on the windward side.

[0012] Furthermore, the air cooler includes at least an air-cooled pipe installed in the water collection and mist-expelling channel, and an air-cooled exhaust pipe and an air-cooled induced draft fan are installed at the air outlet of the air-cooled pipe, with the air-cooled induced draft fan drawing ambient air from the air-cooled pipe.

[0013] Furthermore, the air-cooled tubes are finned tubes or plain tubes. Each air-cooled tube is set perpendicular to the gas flow direction in the water collection and mist driving channel. Multiple tubes are set in each column, and multiple columns are set along the gas flow direction. Adjacent columns of air-cooled tubes are staggered on the windward side.

[0014] Furthermore, the air collecting hood includes an air collecting hood body and an air collecting hood base. The air collecting hood body is fixed on the air collecting hood base, and multiple sets of ventilation windows are provided on both the air collecting hood body and the air collecting hood base.

[0015] Furthermore, a circulating air shower system is installed on the exhaust duct. The circulating air shower system includes an air box and an air duct. The air box is arranged in a ring around the perimeter of the exhaust duct, and the air duct connects the air box and the air outlet of the air cooler.

[0016] Furthermore, a water collection device is installed on the lower side of the condenser, air cooler, and induced draft duct. The water collection device includes a steam-water separator and a water collection tank. The water collection tank is located below the steam-water separator, and a drain pipe is installed on the side wall of the water collection tank.

[0017] Furthermore, a condenser is added to the rear side of the air cooler inside the water collection and mist removal channel.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] This utility model provides a steam-water separation and demisting device for cooling towers, which is installed at the air outlet of existing cooling towers. It has minimal impact on the operation of existing cooling towers. Based on the basic process of "water vapor collection → cascade condensation → inertial impact → circulating air shower system", it greatly improves the water collection rate of the evaporated water vapor in the cooling tower. At the same time, it can efficiently eliminate plume mist and has environmental protection functions. In addition, it effectively recovers the moisture in the hot and humid air discharged from the cooling tower, realizes water recycling, and saves water resources. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0021] Figure 2 This is a schematic diagram of the structure of the air collection shroud of this utility model.

[0022] Figure 3 for Figure 2 AA sectional view.

[0023] Figure 4 This is a cross-sectional view of the condenser of this utility model.

[0024] Figure 5 for Figure 4 BB cross-sectional view.

[0025] Figure 6 This is a cross-sectional view of the air cooler of this utility model.

[0026] Figure 7 for Figure 6 CC section view.

[0027] Among them: 1. Air collection hood; 1-1. Air collection hood body; 1-2. Air collection hood base; 1-3. Ventilation window;

[0028] 2. Condenser; 2-1. Condenser tube;

[0029] 3. Air cooler; 3-1. Air cooler pipes; 3-2. Air cooler induced draft fan;

[0030] 4. Water collection and mist dispersing channel;

[0031] 5. Exhaust fan;

[0032] 6. Steam-water separator;

[0033] 7. Air duct;

[0034] 8. Water collection tank;

[0035] 9. Circulating air shower system;

[0036] 10. Cooling tower fan;

[0037] 11. Low ventilation duct.

[0038] In the diagram: red arrows indicate the direction of hot and humid air flow, green arrows indicate the direction of condensate collection, and black arrows indicate the direction of refrigerant flow in the condenser or the direction of cooling air flow in the air cooler. Detailed Implementation

[0039] The specific embodiments of this utility model will be further explained below with reference to the accompanying drawings.

[0040] like Figures 1-7 As shown, a steam-water separation and demisting device for a cooling tower is installed on one side of the top of the cooling tower, or symmetrically on both sides of the cooling tower, or even on multiple sides of the top of the cooling tower. It mainly includes a wind collector hood 1, a water collection and demisting channel 4, a condenser 2, an air cooler 3, an exhaust duct 5, a circulating air shower system 9, and a water collection device.

[0041] Single-sided configuration can be single-suction, double-sided configuration can be double-suction, and multi-sided configuration can be multi-suction, but double-suction is the best, as it results in a more balanced system pressure and better efficiency in air-water separation and mist removal. This embodiment uses a double-sided symmetrical configuration as an example for the main explanation.

[0042] The top of the cooling tower body is the cooling tower air outlet. A cooling tower fan 10 is installed at the cooling tower air outlet. It can be an electric fan or a water fan to draw humid and hot saturated air from the cooling tower and discharge it to the outside of the tower. At the same time, a dedicated low wind duct 11 is installed around the outside of the cooling tower air outlet to facilitate the concentrated discharge of humid and hot saturated air into the upper air collection hood 1.

[0043] The air collecting hood 1 is located at the air outlet of the cooling tower and includes an air collecting hood body 1-1 and an air collecting hood base 1-2. The air collecting hood base 1-2 is symmetrically and parallelly arranged on the outside of the short air duct 11. The air collecting hood body 1-1 is a herringbone-shaped air collecting hood with an open bottom. Figure 3 As shown, its bottom opening corresponds to the air outlet of the cooling tower, and the air collecting hood body 1-1 is fixed on the air collecting hood base 1-2 on both sides; both the air collecting hood body 1-1 and the air collecting hood base 1-2 are frame structures, and by installing multiple sets of glass, a herringbone hood structure is formed with the front and rear sides closed and the air collecting hood air outlets on the left and right sides.

[0044] Meanwhile, multiple ventilation windows 1-3 are installed on both the main body 1-1 and the base 1-2 of the air collecting hood. The purpose is that when the ambient temperature is too high in summer, the air resistance at the cooling tower outlet is too large, resulting in poor cooling effect. At this time, the ventilation windows 1-3 on the main body 1-1 and / or the base 1-2 of the air collecting hood can be opened as needed. Although a small amount of water collection effect is lost, the air resistance is reduced, the cooling efficiency inside the cooling tower is improved, and the normal operation of the system is guaranteed.

[0045] The advantages of this air collector hood design are as follows: 1. The large opening at the bottom of the air collector hood completely covers the air outlet of the cooling tower. The CFD simulation-optimized herringbone-shaped air collector hood achieves a water vapor collection rate of over 95%. 2. By adding a base to the air collector hood, its height is increased, providing a buffer space for the humid and hot saturated air extracted by the cooling tower fan to release some of its kinetic energy, reducing wind resistance, enhancing the cooling effect, and ensuring system stability. 3. The front and rear sides of the air collector hood have relatively gentle slopes, facilitating the installation of multiple ventilation windows and effectively ensuring the normal operation of the system in summer.

[0046] The air collecting hood 1 has a horizontally arranged water collection and mist driving channel 4 at the air outlet. A condenser 2 and an air cooler 3 are arranged in sequence inside the water collection and mist driving channel 4. An air duct 5 is arranged at the end of the water collection and mist driving channel 4. The air duct 5 is installed vertically. The air inlet of the air duct 5 is connected to the air outlet of the water collection and mist driving channel 4. The air outlet of the air duct 5 is located at the top of the air duct 5.

[0047] The water collection and mist dispersing channels 4 are symmetrically arranged on both sides of the air collecting hood 1, corresponding to the air outlet of the air collecting hood, and serve as a circulation channel for humid and hot saturated air.

[0048] The condenser 2 includes at least a condenser tube 2-1 installed in the water collection and mist removal channel 4. The condenser tube 2-1 is supplied with refrigerant, such as ethylene glycol, by a refrigeration unit installed outside the cooling tower. The two are connected by a pipe. After the heat exchange is completed, the refrigerant flows back to the refrigeration unit for the next refrigeration cycle. Some water molecules in the humid and hot saturated air discharged from the cooling tower condense instantly upon encountering the condenser tube, forming condensate.

[0049] The condenser tube 2-1 can be a cold storage coil, such as a U-shaped coil. One coil is one row, and multiple coils (rows) can be set up. They are installed in a stepped staggered manner, that is, each condenser tube 2-1 is set perpendicular to the gas flow direction in the water collection and mist driving channel 4. Multiple coils (rows) are set up along the gas flow direction. The condenser tubes 2-1 of adjacent two rows are staggered on the windward side. The advantage of this arrangement is that when the humid and hot saturated air passes through the condenser tube 2-1, the turbulence effect is increased, the heat transfer efficiency is improved, and thus the condensation effect is improved.

[0050] In addition, each condenser tube can be set up as a separate line connected to the refrigeration unit, or 2 to 3 condenser tubes 2-1 spaced apart can be connected end to end to form a line connected to the refrigeration unit, and the refrigeration unit can supply refrigerant to the condenser tubes 2-1.

[0051] The air cooler 3 includes at least an air-cooled tube 3-1 disposed within the water collection and mist-expelling channel 4. An air-cooled exhaust duct and an air-cooled induced draft fan 3-2 are disposed at the air outlet of the air-cooled tube 3-1. Specifically, the air-cooled tube 3-1 is a biomimetic finned tube or a smooth tube, with the fins adopting a fractal structure of ginkgo leaf veins and a fin ratio ≥15. The air-cooled tubes can be arranged in multiple rows, with multiple tubes in each row, or in a staggered ladder installation method. That is, each row of air-cooled tubes 3-1 is arranged perpendicular to the gas flow direction in the water collection and mist-expelling channel 4, with multiple tubes in each row, and multiple rows are arranged along the gas flow direction. Adjacent rows of air-cooled tubes 3-1 are staggered on the windward side to improve the condensation efficiency of the air-cooled tubes. At the same time, it can also improve the effect of inertial impact condensation of the air-cooled tubes by the humid and hot air.

[0052] An opening is provided at the air inlet of the air-cooled pipe in the water collection and de-fogging channel 4, and an opening is provided at the air outlet of the air-cooled pipe in the water collection and de-fogging channel 4. An upward-facing air-cooled exhaust pipe is provided at the air outlet of the air-cooled pipe, and an air-cooled induced draft fan 3-2 is provided at the air outlet of the air-cooled exhaust pipe. Under the suction of the air-cooled induced draft fan 3-2, the ambient cold air is drawn into the air-cooled pipe 3-1, while some water molecules in the humid and hot air discharged from the condenser 2 condense instantly upon encountering the air-cooled pipe, forming condensate.

[0053] It should be noted that, apart from the condenser tube 2-1 and the air-cooler tube 3-1, which play the main role, the condenser 2 and the air-cooler 3 can be separately equipped with their own shells installed at the corresponding positions of the water collection and mist driving channel 4. However, it can also be considered that the part of the water collection and mist driving channel 4 corresponding to the condenser tube 2-1 and the air-cooler tube 3-1 is the shell of the condenser 2 and the air-cooler 3.

[0054] In addition, it should be noted that an identical condenser 2 can be added to the rear side of the air cooler 3 to improve the efficiency of water collection and mist removal of this device.

[0055] The air duct 5 is vertically installed at the end of the water collection and mist driving channel 4 and connected to it, and the air outlet of the air duct 5 is located at the top of the air duct 5.

[0056] To enhance the defogging effect of this device, a circulating air shower system 9 is installed at the top of the air duct 5. The circulating air shower system 9 includes a wind box and an air guide pipe 7. The wind box is arranged in a ring around the top periphery of the air duct 5. The two ends of the air guide pipe 7 are connected to the wind box and the air outlet of the air cooler 3, respectively. The air outlet of the air cooler 3 is the outlet of the air-cooled exhaust pipe. Its function is to blow the hot air discharged from the air-cooled pipe into the air outlet at the end of the air duct 5 through the air-cooled exhaust fan 3-2, accelerate the evaporation of water vapor containing a small amount of water molecules, further disperse the water molecules, and achieve a better defogging effect.

[0057] A water collection device is installed on the lower side of the condenser 2, air cooler 3, and exhaust duct 5. The water collection device includes a steam-water separator 6 and a water collection tank 8. The water collection tank 8 is located below the steam-water separator 6. The steam-water separator 6 is a perforated air guide plate, which can prevent the air flowing through the water collection and mist driving channel 4 from carrying away the water molecules in the lower water collection tank 8, and can also allow the condensate to flow into the lower water collection tank 8 through the perforations. A drainage pipe is installed on the side wall of the water collection tank 8, and the collected condensate flows through the drainage pipe to the water pool in the cooling tower for recycling, so as to save water resources.

[0058] The water collection and mist dispersing process in this embodiment includes the following steps:

[0059] 1. The water vapor collection process of the wind collector hood:

[0060] The hot, humid air drawn out by the cooling tower fan is drawn into the adjustable herringbone-shaped air collector hood above the low-profile fan duct. The air is propelled into the hood by the dynamic pressure of the air outlet from the low-profile fan duct and then transported to the water collection and mist-driving channels on both sides. In actual operation, the opening and closing degree of the air collector hood can be adjusted according to changes in ambient temperature. In summer, when the cooling tower needs to cool down, multiple ventilation windows are opened to increase the opening degree of the air collector hood; in spring, autumn and winter, when the temperature reduction requirement is not high, multiple ventilation windows are closed to reduce the opening degree of the air collector hood.

[0061] 2. The cascade condensation process of the condenser:

[0062] The hot, humid saturated air initially impacts the condenser, creating turbulence, and then condenses instantly into water droplets upon encountering the condenser tube, forming initial condensation. The condensed water droplets fall into the water vapor separator below and are collected in the water collection tank.

[0063] In this step, the steam-water separation rate of the humid, hot, saturated air after passing through the condenser is 17-25%.

[0064] 3. The inertial impact condensation process of the air cooler:

[0065] The remaining unsaturated humid air undergoes a secondary impact as it passes through the air-cooled pipe. Under the influence of inertia, water molecules are impacted and separated, forming water droplets. At the same time, some air condenses into water droplets during heat exchange in the air-cooled pipe, and finally flows into the water vapor separator and water collection tank below.

[0066] In this step, the remaining unsaturated air has a steam-water separation rate of 13-20% after passing through the air cooler.

[0067] During winter operation (e.g., when the ambient temperature is below 10℃), the refrigeration unit is shut down. The cold ambient air is introduced into the air-cooled pipe by the induced draft fan. The air condensation and defogging effect can be achieved by exchanging heat between the ambient temperature and the humid air. The condenser and air cooler can be switched according to the ambient temperature.

[0068] 4. The accelerated fog removal process of the circulating air shower system:

[0069] The humid and hot air, after passing through the condenser, air cooler, and (the added condenser), finally enters the exhaust duct and is discharged. The hot air drawn out by the air-cooled exhaust fan is introduced into the exhaust duct outlet through the air duct. The high temperature of the air accelerates the evaporation of the unsaturated air with low moisture content, quickly dispersing the small amount of mist. At the same time, it increases the air velocity at the exhaust duct outlet, further dispersing the fog and achieving the purpose of defogging.

[0070] 5. Condensate collection process by the water collection device:

[0071] The condensate droplets from the above steps all flow into the water vapor separator and water collection tank below, and finally flow through the diversion pipe to the water pool in the cooling tower for recycling, thus achieving the purpose of water collection.

[0072] Finally, it should be noted that the above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. However, any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A steam-water separation and demisting device for a cooling tower, installed at the top of the cooling tower, characterized in that, It includes an air collecting hood (1) installed at the air outlet of the cooling tower, a water collection and mist driving channel (4) installed at the air outlet of the air collecting hood, a condenser (2) and an air cooler (3) installed in sequence in the water collection and mist driving channel (4), and an exhaust duct (5) installed at the end of the water collection and mist driving channel (4). The exhaust duct (5) is installed vertically, and the air outlet of the exhaust duct (5) is located at the top of the exhaust duct (5).

2. The steam-water separation and demisting device for a cooling tower according to claim 1, characterized in that, The condenser (2) includes at least a condenser tube (2-1) installed in the water collection and mist driving channel (4). Both ends of the condenser tube (2-1) are connected to the refrigerator, and the refrigerator delivers refrigerant to the condenser tube (2-1).

3. The steam-water separation and demisting device for a cooling tower according to claim 2, characterized in that, The condenser tube (2-1) is a cold storage coil. Each condenser tube (2-1) is set perpendicular to the gas flow direction in the water collection and mist driving channel (4). Multiple condenser tubes are set along the gas flow direction, and adjacent condenser tubes (2-1) are staggered on the windward side.

4. The steam-water separation and demisting device for a cooling tower according to claim 1, characterized in that, The air cooler (3) includes at least an air cooler pipe (3-1) installed in the water collection and mist driving channel (4). An air cooler exhaust pipe and an air cooler fan (3-2) are installed at the air outlet of the air cooler pipe (3-1). The air cooler fan (3-2) draws ambient air from the air cooler pipe (3-1).

5. A steam-water separation and demisting device for a cooling tower according to claim 4, characterized in that, The air-cooled tube (3-1) is a finned tube or a bare tube. Each air-cooled tube (3-1) is set perpendicular to the gas flow direction in the water collection and mist driving channel (4). Multiple tubes are set in each column, and multiple columns are set along the gas flow direction. Adjacent columns of air-cooled tubes (3-1) are staggered on the windward side.

6. A steam-water separation and demisting device for a cooling tower according to claim 1, characterized in that, The air collecting hood (1) includes an air collecting hood body (1-1) and an air collecting hood base (1-2). The air collecting hood body (1-1) is fixed on the air collecting hood base (1-2). Multiple sets of ventilation windows (1-3) are provided on both the air collecting hood body (1-1) and the air collecting hood base (1-2).

7. A steam-water separation and demisting device for a cooling tower according to claim 1, characterized in that, A circulating air shower system (9) is installed on the duct (5). The circulating air shower system (9) includes a wind box and a guide pipe (7). The wind box is arranged in a ring around the duct (5). The guide pipe (7) connects the wind box and the air outlet of the air cooler (3).

8. A steam-water separation and demisting device for a cooling tower according to claim 1, characterized in that, A water collection device is provided on the lower side of the condenser (2), air cooler (3) and duct (5). The water collection device includes a steam-water separator (6) and a water collection tank (8). The water collection tank (8) is located below the steam-water separator (6), and a drain pipe is installed on the side wall of the water collection tank (8).

9. A steam-water separation and demisting device for a cooling tower according to claim 1, characterized in that, A condenser (2) is added to the rear side of the air cooler (3) in the water collection and mist dispersing channel (4).

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