JPH041274B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dry/wet cooling tower, and in particular to a dry cooling tower that can lower the installation position of a heavy dry cooling section consisting of a group of heat transfer tubes, and downsize and simplify the support structure of the dry cooling section.・Regarding wet cooling towers.

A dry/wet cooling water tower is a device that cools hot water generated in plants such as chemical factories, steel mills, power plants, etc. It has a dry cooling section that cools hot water and cold air (outside air) by indirect heat exchange , and a wet cooling section that performs direct heat exchange for cooling. FIG. 1 shows a conventional example of a countercurrent type dry/wet cooling water tower that cools hot water by causing cold air rising to flow countercurrently to hot water flowing down a wet cooling section.

As shown in the figure, the upper side wall and the bottom side wall of the cooling tower a are provided with outside air intake ports b and c, respectively, and a wet cooling section having a packed bed in which hot water flows down is provided in the middle part of the tower a. d is provided. Above the wet cooling section d, there is a sprinkler pipe e that sprays hot water.
is installed. The hot water that is sprayed from the sprinkler pipe e and flows down the packed bed of the wet cooling section d is introduced into the tower a from the intake port c at the bottom of the cooling tower a, and is cooled by direct contact with the outside air rising up the packed bed. . On the other hand, the hot water flowing down the packed bed of the wet cooling section d is cooled and the humid air containing a large amount of moisture flows into the plenum section f at the upper part of the tower a. In winter, if this humid air is released to the atmosphere from the exhaust stack g, it will generate white smoke and cause a pollution problem. Introducing high temperature dry air,
After being mixed with the moist air, it is discharged from the exhaust stack g to prevent the exhaust from turning into white smoke.

By the way, the dry cooling section h consists of a large number of heat transfer tube groups for transferring hot water, and is installed on the side wall of the plenum section f at the top of the tower. Therefore, when increasing the capacity of the dry cooling section h and increasing the air intake area, Since it is necessary to increase the height of the plenum part f, the tower height also increases,
This creates unnecessary space in the plenum part f. Furthermore, although the dry cooling section h is heavy, in the conventional cooling tower a described above, the dry cooling section h is installed in the upper part of the tower a above the wet cooling section d. For this reason,
The frame i for supporting the dry cooling section h has become large, which not only increases the construction cost but also requires a large installation area.

The present invention was devised to effectively solve the above-mentioned conventional problems, and an object of the present invention is to change the heat transfer area of a dry cooling section consisting of a group of heat transfer tubes by changing the height of a conventional water cooling tower. In addition, the installation position of the heavy dry cooling section can be lowered to the outside of the wet cooling section in the middle of the tower, making the supporting frame of the dry cooling section smaller and simpler, and reducing its installation space. The purpose of the present invention is to provide a dry/wet type cooling water tower that can achieve this.

According to the present invention, the above object is achieved by the following configuration. In other words, a dry cooling section is installed outside the wet cooling section in the middle of the countercurrent cooling tower via an air damper to lower the installation position of the dry cooling section, and the dry air from the dry cooling section and the wet cooling section are installed at a lower position. In order to mix the moist air from the inside of the tower at the upper part of the tower, the part of the packed bed facing the air damper is separated by a partition wall, and a water spray system is installed to spray hot water to each of the packed beds divided by the partition wall. During dry/wet operation, hot water is not allowed to flow through the packed bed section partitioned by the partition wall, and the dry air from the dry cooling section is directly guided to the upper part of the tower.

A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

In FIG. 2, 1 is a cylindrical cooling water tower;
An air damper 2 is provided on the bottom side wall of the cooling tower 1, and an exhaust pipe 3 is provided at the center of the upper wall of the cooling tower 1 for venting outside air introduced into the tower to the atmosphere. In the middle of the cooling tower 1 above the air damper 2, there is a wet cooling section 4 that partitions the bottom of the tower and the top of the tower.
is provided. The wet cooling unit 4 is filled with wood or the like to form a packed layer S through which hot water flows. Further, an air damper 5 is provided on the side wall of the cooling tower 1 surrounding the wet cooling section 4, and a dry cooling section 6 is provided outside the air damper 5. The dry cooling unit 6 consists of a group of heat transfer tubes for transferring hot water, and is placed on a frame 7 erected on a foundation.

The wet cooling unit 4 is provided with a partition wall 8 that partitions a packed layer S ₁ on the outer periphery facing the air damper 5 . S ₁ and other central packed bed S ₂
It is divided into. Furthermore, an air damper 9 is provided at the bottom of the packed bed _S1 . A water sprinkling pipe T having a water nozzle for spraying hot water sent from a plant or the like to the wet cooling part 4 is disposed above the wet cooling part 4 . Water pipe T
is branched into a water sprinkling pipe T ₁ that sprays hot water onto the packed bed S ₁ and a water sprinkling pipe T ₂ that sprays hot water onto the packed bed S ₂ .
Further, a cold water tank 10 is provided at the bottom of the cold water tower 1 to store cooling water cooled by the wet cooling section 4, and a fan 11 for forced exhaust is provided in the exhaust pipe 3.

Next, the operation of this embodiment will be described.

First, normal wet operation (cooling of hot water is performed only by the wet cooling section 4) when there is no possibility that the exhaust gas from the cooling tower 1 will turn into white smoke, such as during summer, will be described. This situation during normal wet operation is shown in the left half of the cooling tower 1 divided by the cooling tower axis c in FIG. During normal wet operation, the air damper 5 is closed, the air damper 9 is opened, and the valve V ₁ of the water sprinkler pipe T ₁ is opened.

Hot water sent from plants etc. is sent through sprinkler pipes.
The water is dispersed from T ₁ and T ₂ to the packed beds S ₁ and S ₂ of the wet cooling section ₄ , respectively, and flows down through the packed beds S 1 and S ₂ . The introduced outside air rises through the packed beds S ₁ and S ₂ . In this way, the hot water flowing down the packed beds S ₁ and S ₂ is cooled by the rising outside air, and the cooled cooling water is stored in the cold water tank 10 and returned to the plant system, etc. On the other hand, the hot water is subjected to cooling treatment. The outside air is exhausted from the exhaust pipe 3 through the upper part of the tower.

Next, a description will be given of dry/wet operation when hot water cooling of the dry cooling section 4 alone cannot avoid turning the exhaust air into white smoke, such as during winter. The conditions during this dry/wet operation are shown on the right half of the cooling tower 1, with the air damper 5 open, the air damper 9 closed, and the valve _V1 closed.

Since the valve V ₁ of the water sprinkler pipe T ₁ is closed, hot water is not sprayed onto the packed bed S ₁ and the packed bed S ₁ is in a dry state. Therefore, the high-temperature dry air that has flowed into the packed bed S ₁ through the dry cooling section 6 and the air damper 5 continues to rise through the packed bed S ₁ and reach the upper part of the tower. On the other hand, the outside air introduced into the tower from the air damper 2 at the bottom of the cooling water tower 1 cools the hot water that is sprayed from _{the sprinkler pipe T 2 and} flows down the packed bed S 2 while rising up the packed bed S ₂ , and It flows into the upper part of the tower. The moist air from the packed bed S ₂ is mixed with the dry air from the packed bed S ₁ in the upper part of the tower, and is released to the atmosphere from the exhaust stack 3. Humid air mixes with dry air and is discharged after the humidity has decreased, so no white smoke is produced.

In this way, the present invention uses the conventional countercurrent drying method.
In a wet cooling tower, the tower side wall around the outer periphery of the wet cooling section 4, which was in a sealed state, is effectively used, and an air damper 5 is installed here.
A dry cooling section 6 is further provided outside the air damper 5. Therefore, the installation position of the heavy dry cooling section 6 in the middle part of the cooling tower 1, which is on the same level as the wet cooling section 4, can be lowered. Therefore, since the side wall of the packed tank portion, which accounts for a large proportion of the side wall area, can be fully utilized, the heat transfer area of the dry cooling section can be widened and the degree of freedom in design is increased without increasing the height of the inside of the column. Further, the frame 7 supporting the dry cooling section 6 can be made small and simple, and the construction cost and installation space can be reduced, and the stability of the dry cooling section 6 can be improved.

In summary, according to the present invention, space can be secured for the dry cooling section which requires a wide opening area, and the installation position of the heavy dry cooling section can be lowered to the outside of the wet cooling section in the middle of the tower. The support frame of the dry cooling section can be made smaller and simpler, and the construction cost and installation space can be reduced, which is an excellent effect.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of a conventional dry/wet type cooling water tower, and FIG. 2 is a side sectional view showing an embodiment of the dry/wet type cooling water tower according to the present invention. In the figure, 1 is a cooling tower, 2, 5, and 9 are air dampers, 4 is a wet cooling section, 6 is a dry cooling section, 7 is a frame, 8 is a partition wall, S, S ₁ , and S ₂ are packed beds, and T , T ₁ ,
T ₂ is the water pipe.

Claims (1)

[Claims] 1. A wet cooling section that has a packed bed that allows hot water sprayed from the top of the tower to flow down, and that cools the hot water with cold air that flows in from the bottom of the tower and rises above the packed bed, and an air damper is installed outside the packed bed of the wet cooling section. A dry cooling unit provided through the air tamper, a partition wall that partitions a portion of the packed bed facing the air tamper, and a water sprinkling system arranged to spray warm water to each of the packed beds divided by the partition wall. A dry/wet type cooling water tower.