JPS6242307Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field] This invention relates to a cooling tower equipped with a closed heat exchanger through which water to be cooled flows while being isolated from the atmosphere.

[Prior art]

In a cooling tower of this type prior to the filing of this application, a closed heat exchanger is placed under a water sprinkler, and the water to be cooled flowing inside the closed heat exchanger is sprayed on the surface of the heat exchanger and is sprayed with water flowing down. Cooling towers are well known, but the temperature of the circulating spray water must always be maintained lower than the water to be cooled, and compared to open cooling towers that have a filling plate placed below the water sprinkler. , since no cooling effect can be expected from the latent heat of vaporization of the water to be cooled, there is a disadvantage that the equipment will be larger to obtain the same heat exchange rate as an open type cooling tower, and the outer surface of the closed type heat exchanger must be The pressure loss of the air discharged to the outside is generally higher than that of the filler, which increases the load on the blower (approximately twice as much) and increases noise.

In order to supplement the heat exchange efficiency of the hermetic heat exchanger, a cooling tower was developed in 1972, in which a filling plate was placed partially submerged in the lower water tank below the hermetic heat exchanger.
Although it is described in Publication No. 75955, the noise caused by the rotation of the blower has not yet been solved, and there is still room for improvement in the heat exchange rate between the spray water and the water to be cooled.

In JP-A No. 51-60047, which is in the name of the applicant company, a closed heat exchanger is divided into upper and lower parts, the lower heat exchanger (plate coil) on the high-temperature side is buried in the lower water tank, and the lower heat exchanger (plate coil) on the high temperature side is buried in the lower water tank. Above the upper heat exchanger (plate coil), a cooling tower with a filling material placed below the spray water device is described, and the position of indirect contact between the water to be cooled flowing inside the closed heat exchanger and the spray water, Efforts have been made to increase the heat exchange efficiency by increasing the contact time, but this leads to an increase in the size of the heat exchanger, which leads to an increase in the size of the cooling tower, and there is a drawback that the noise generated from the blower has not yet been sufficiently reduced.

〔the purpose〕

This invention eliminates the drawbacks of the prior art, incorporates the advantages of the packed plate of an open cooling tower into a closed cooling tower, and devises the structure and arrangement of the heat exchanger,
The main object is to provide a cooling tower which can effectively exchange heat between sprayed water and cooled water, keep sprayed water at a constant low temperature, and perform low-noise operation.

〔composition〕

In this design, multiple heat exchange plates are installed in parallel inside the main body between the cooling tower water sprinkler and the outside air intake provided in the outer casing of the cooling tower, and the area near the water surface of the lower water tank is isolated from the atmosphere. A double pipe heat exchanger is installed, which has dual passages inside and outside for the cooled water to be cooled and the sprayed water from this sprinkler, and the direction of flow of the cooled water and the sprayed water is It is contradictory,
A strainer located in the spray water of the lower water tank is connected to the suction port of the spray water pipe in this heat exchanger, and its discharge side is connected to the sprinkler device via a water pump and a water pump, This cooling tower achieves all of the above main objectives by using a cooling tower that is characterized by forming a circulation system for sprayed water.

Next, a typical embodiment of this invention will be explained based on the drawings.

1 to 3, reference numeral 10 denotes an outer casing of a countercurrent cooling tower. A blower 11 is provided at the upper end of the outer casing 10, and an eliminator is inserted into the outer casing 10 from above. 12. A watering device 13 and a filler 14 are arranged, a lower water tank 15 is formed at the lower end of the outer casing 10, and an outside air intake port 16 is provided on the peripheral wall of the outer casing 10 between the lower water tank 15 and the lower end of the filler. There is.

In the sprayed water of the lower water tank 15, there is a double passage 17 for cooled water that circulates through a refrigerator and the like, and for sprayed water that is sprayed onto the filler 14 from the water sprinkler 13.
A double tube heat exchanger 19 with 18 is completely submerged with its passages 17, 18 horizontal.

The inner pipe 20 forming the spray water passage 17 is meanderingly bent in a horizontal plane, and a suction port 20a, which is one end of the inner pipe 20, has a strainer 21 located in the spray water that falls into the lower water tank 15 and is collected. The discharge side 20b of this inner pipe 20 is connected to the water sprinkling device 13 via a water pump P and a water pump 22, forming a circulation system for sprayed water.

A hollow tube 23 with both ends closed is fitted into each straight portion of the meandering and bent inner tube 20 with a gap,
The adjacent hollow tubes 23 are formed into hollow short tubes 24 having a zigzag cooled water passage 18 formed on the outer periphery of the inner tube.
and communicate with each other at their ends.

The flow direction of the cooled water flowing in the passage 18 is opposite to the flow direction of the sprayed water flowing in the passage 17, and one end 18a of the cooled water passage 18
18b serves as a supply port for receiving high-temperature water to be cooled that circulates within the refrigerator, and the other end 18b serves as a discharge port for returning the water indirectly cooled by the sprayed water to the refrigerator or the like.

In the embodiment, the heat exchanger 19 is arranged horizontally in the lower water tank 15, but the passage 1
Even if the heat exchanger 19 is arranged in the lower water tank 15 in such a manner that 7 and 18 are vertical, and the heat exchanger 19 is placed above the water surface, this device is the same; may be used as the cooled water passage, and the inner passage may be used as the sprayed water passage.In short, if the cooled water passage and the sprayed water passage coexist in one heat exchanger 19 via the pipe wall, the heat exchanger The shape of the outline does not matter. However, when the heat exchanger 19 is placed in the lower water tank 15, the outside always becomes the water passage to be cooled.

[Effect]

The operation of the cooling tower of this invention having the above configuration will be explained.

First, the lower water tank 15 is filled with water, and the freezing pipe of the refrigerator is connected to the supply port end 18a and the discharge port end 18b of the cooled water passage 18 of the double tube heat exchanger 19, and the supply port end The water to be cooled flows in a meandering zigzag manner into the passage 18 from 18a toward the discharge end 18b. on the other hand,
When the pump P is started, the water in the lower water tank 15 is guided into the inner pipe through the strainer 21, and is caused to flow through the inner pipe 20 while meandering in a zigzag manner in the opposite direction to the flow direction of the water to be cooled. During this meandering flow, the sprayed water and the water to be cooled come into indirect contact through the pipe wall, and heat is exchanged between them. It is returned to the machine and circulated. On the other hand, water that absorbs heat and becomes slightly warmer,
The water is pumped up through the water lift pipe 22 to the water sprinkler 13 located above by the action of the pump P, and then sprayed onto the filling material 14 from the water sprinkler 13 . While flowing along the wall surface of the filler 14, it comes into contact with the outside air sucked into the outer casing 10 from the outside air intake port 16 by the drive of the blower 11, and due to the latent heat of vaporization due to the evaporation of the warmed spray water. As a result, the temperature of the sprayed water decreases rapidly, naturally falls onto the lower water tank 15, and is circulated.

〔effect〕

In the present invention constructed and operated as described above, water is pumped up from the inside of the cooled water tank 15 to the water sprinkler 13, sprinkled on the filler 14, and then returned to the lower water tank 1.
Sprayed water and water to be cooled are collected and circulated through the inner and outer passages 1 of the double-tube heat exchanger 19.
7 and 18, the flow directions are opposite to each other, so heat is transferred indirectly through the pipe walls, and the temperature of the cooled water and the sprayed water decreases in each part of the inner and outer passages 17 and 18. Since the difference is large and the contact area occupies a larger area than that of conventional cooling towers, the heat of the high-temperature water to be cooled can be efficiently absorbed into the spray water, and the closed heat exchanger can be installed near the bottom of the spray device 13. By simply arranging only the filler 14 directly below the dispersion device 13 without providing it at all in the ventilation area, heat exchange is equivalent to or better than that of a closed cooling tower with a closed heat exchanger arranged in the ventilation area. In addition, the air sucked into the outer casing 10 by the operation of the blower 11 flows counter-currently or cross-currently only in the filler-filled area and is exhausted to the outside air, reducing pressure loss. Noise generated by driving the blower 11 can be suppressed to a lower level.

Since the double-tube heat exchanger 19 has the above-described structure, if its external dimensions are manufactured in advance to match the size of the cooling tower with the minimum capacity, it can be used as a unit to accommodate other capacities. Depending on the size of the cooling tower,
Combining multiple pieces, for example, stacking them in the lower water tank 15,
Alternatively, by connecting and installing them in parallel, the water to be cooled can be cooled, and the manufacture and maintenance of the heat exchanger 19 can be facilitated.

As an effect of the embodiment, when the double-pipe heat exchanger 19 is arranged horizontally above the water surface of the lower water tank 14, the sprayed water falling from the filler 14 is once transferred to the heat exchanger 19. This heat exchanger 19
After flowing along the outer circumferential surface of the cooling water tank, the water flows down into the lower water tank 15, so that the dripping water does not directly hit the liquid surface of the lower water tank, the dripping sound is quieter, and the outer passage 18 becomes a cooled water passage. When at least a part of the double heat exchanger 19 is submerged in the lower water tank 15 that can cool the water to be cooled more effectively from inside and outside, the outer wall of the water passage to be cooled is The water to be cooled is washed by the spray water flowing toward the strainer 14 in the lower water tank 15, and in cooperation with the spray water flowing through the inner pipe 17, the water to be cooled is cooled from inside and outside, and the water is cooled on the surface of the double-pipe heat exchanger. The adhering water scale can be washed away by the flowing spray water, so that it does not adhere much to these surfaces.

When the double-tube heat exchanger 19 is arranged horizontally, the water to be cooled can be effectively cooled without increasing the height of the cooling tower. When the heat exchanger 19 is submerged in the tank, a large number of double-tube heat exchangers 19 can be easily installed and used in parallel, avoiding various piping in the lower water tank.

[Brief explanation of the drawing]

The figures show a typical embodiment of this invention; FIG. 1 is a schematic overall view thereof, FIG. 2 is a plan view showing an example of a double tube heat exchanger, and FIG. FIG. 3 is an enlarged longitudinal sectional view taken along line 3-3 in FIG. 2; Explanation of main symbols in the diagram, 13... Watering device, 1
4...Filling material, 15...Lower water tank, 19...Double pipe heat exchanger.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A plurality of heat exchange plates are installed in parallel in the cooling tower body between the water sprinkler system of the cooling tower and the outside air intake provided in the outer casing of the cooling tower, and near the water surface of the lower water tank. The system is equipped with a double-pipe heat exchanger that has double passages inside and outside for the cooled water that is cooled while isolated from the atmosphere and the sprayed water from this water spraying device. The direction of water flow is opposite,
A strainer located in the spray water of the lower water tank is connected to the suction port of the spray water pipe in this heat exchanger, and its discharge side is connected to the sprinkler device via a pump and a pump pipe, A cooling tower characterized by forming a circulation system path for sprayed water. 2. The cooling tower according to claim 1, wherein the double-pipe heat exchanger is arranged horizontally above the water surface of the lower water tank. 3. The cooling tower according to claim 1, wherein the double-pipe heat exchanger is at least partially submerged in the sprayed water of the lower water tank. 4 Of the inner and outer double pipes of the double pipe heat exchanger,
2. The cooling tower according to claim 1, wherein an inner pipe is formed in the passage for the sprayed water, and an outer pipe that surrounds the inner pipe and meanderes is formed in the passage for the water to be cooled. 5. The cooling tower according to claim 1, wherein the double-tube heat exchanger stands perpendicular to the water surface of the lower water tank and is submerged in the sprayed water of the lower water tank. 6. The cooling tower according to claim 2, 3, or 4, wherein a plurality of the double-tube heat exchangers are hierarchically arranged in a lower water tank and interconnected.