JP3220435B2 - Crossflow cooling tower with white smoke prevention function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cross-flow cooling tower having a function of preventing generation of white smoke in the middle and winter seasons.

[0002]

2. Description of the Related Art Cooling towers of this type are disclosed in
64, JP-A-2-50083, etc., have already been described and published, and have an initial white smoke prevention effect.

[0003] Among such prior arts, in the cooling tower described in Japanese Utility Model Laid-Open Publication No. 63-190765, the enclosed heat exchanger is divided into two in the direction of air flow, that is, in the depth direction of the cooling tower, to take in outside air. One of the mouth sides is constituted by a bare tube as a wet cooling unit, and the other on the exhaust port side is constituted by a finned tube as a wet / dry cooling unit. Therefore, in the middle and winter, watering to the finned pipe is stopped, and the circulating water is indirectly cooled in the bare pipe, and the high-temperature humid air is passed through the finned pipe, and the high-temperature circulation flowing through the finned pipe is performed. The humid air is heated with water to reduce its absolute humidity, mixed as dry air in a mixing chamber below the exhaust port, and exhausted from the exhaust port to reduce the generation of white smoke. And the arrangement of the finned pipes, the amount of dry air generated can be slightly changed by increasing or decreasing the amount of water sprayed on the bare pipes, but it is not possible to greatly change them by a factor of two or one half. It is possible.

[0004] Next, the cooling tower described in Japanese Patent Application Laid-Open No. Hei 2-50083 developed by the present applicant is filled with a synthetic resin wet heat exchanger and a synthetic resin dry heat exchanger, and the wet heat exchange is performed. Assuming that a cross-flow cooling tower having a white smoke prevention function, which is provided with a blower at an exhaust port for exhausting a mixed air of humid air passed through a vessel and dry air passed through a dry heat exchanger to the atmosphere, The air intake of the wet heat exchanger and the air intake of the dry heat exchanger face the same cooling tower outside air intake, and the air passage of the wet heat exchanger,
The air passages of the dry heat exchanger are parallel to each other, and these heat exchangers are stacked in several stages alternately with different types of adjacent heat exchangers. Also in this case, the aforementioned Japanese Utility Model Laid-Open No.
4, the amount of dry air generated can be slightly changed by increasing or decreasing the amount of sprayed water to the heat exchanger. However, the amount of dry air must be greatly changed, such as twice or half. Is impossible.

If the change in the amount of dry air generated cannot be largely changed as in the above-mentioned prior art, the outside air temperature drops significantly, and a large amount of dry air, that is, the amount of air heating in a humid and humid condition during the rainy season. In some cases, it is not possible to cope with the case where it is necessary, and the function of preventing the generation of white smoke cannot be exhibited.

[0006]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems by improving the upper water tank and the closed type heat exchanger so that the amount of generated dry air can be greatly changed, the outside air temperature can be greatly reduced, and the outside air can be humid. It is an object of the present invention to provide a cross-flow cooling tower with a white smoke prevention function that can greatly change the amount of air heating even at times and can exhibit a sufficient white smoke prevention effect.

[0007]

In order to solve the above-mentioned problems, a specific invention is characterized in that hermetic heat exchangers are arranged vertically below an upper water tank, and supply ends of these hermetic heat exchangers are arranged. Is a cross-flow cooling tower connected to a common supply header on the exhaust port side, and a discharge end thereof is connected to a common discharge header on the outside air intake side, wherein the upper water tank has at least a width direction of the outside air intake port. The closed heat exchangers are divided into at least three heat exchange portions corresponding to the respective water spray portions in the width direction of the outside air intake, and spray water is sprayed into each water spray portion. A cross-flow cooling tower having a white smoke prevention function, characterized in that the supply pipes for supply are each provided with an on-off valve.

The upper water tank is divided into three watering portions in the width direction of the outside air intake of the cross-flow cooling tower, and each of the closed heat exchangers is composed of one cooling coil. Is divided into three heat exchange portions corresponding to the respective water spray portions, and it is desirable that the central heat exchange portion among the three heat exchange portions is formed of a finned pipe.

[0009] In the three heat exchange parts, a vertical partition plate may be interposed at the boundary between the heat exchange parts on both sides and the central heat exchange part.

[0010]

The common operation of the invention described in each of the above-mentioned claims is as follows. In summer, as in the case of this type of cross-flow type cooling tower, the water is sprayed from all the water spray parts to all the heat exchanger groups below, and the circulating cooling water circulating in the heat exchanger groups is indirectly cooled.

Next, during the high temperature and high humidity period, such as the rainy season in Japan, and during the winter period, when white smoke is likely to be generated, the following operation is performed.

[0012] An on-off valve provided on a supply pipe to a central water sprinkling part in the upper water tank partitioned into at least three water sprinkling parts in a width direction of the outside air intake port is closed, and is located on both sides of the central water sprinkling part. Only in the sprinkling part,
Sprinkling water is supplied from a supply pipe, and only in the heat exchange portions located on both sides of each of the hermetically sealed heat exchangers divided into three heat exchange portions corresponding to the respective water spray portions, spray water and circulating cooling are performed. Performs indirect heat exchange with water, directly cools sprayed water by airflow in the heat exchange parts located on both sides, discharges it as humid air to the exhaust side, and makes the center heat exchanger part non-sprayed, circulating The cooling water is indirectly air-cooled to dry air as heating air, and in the depth direction of the closed type heat exchanger, the humid air and the dry air flow to the exhaust port side without mixing as a parallel flow, and the air flows below the exhaust port. The wet air and the dry air are mixed with each other in this mixing chamber, the mixed flow rises toward the exhaust port, and the air flow is made high temperature and low humidity as a whole and exhausted from the exhaust port. Non-supersaturated atmosphere Mind you, it does not involve the generation of white smoke.

Next, when increasing the amount of heated air, spraying water is performed only from the central spraying part, and watering is stopped from both sides of the spraying part. Generate a quantity to prevent the generation of white smoke.

In particular, the specific operation of the second aspect of the invention is as follows. During the rainy season in winter and summer, of the three heat exchange parts in one cooling coil, when the non-sprinkling area is at the center, the circulating cooling water flowing through the finned pipe is cooled by air cooling, and the outside air flow is It flows into the cooling tower exhaust port as a dry air stream.

When the non-sprinkling area is on both sides, the circulating cooling water flowing in the bare pipe is cooled by air cooling, and the outside air stream becomes a dry air stream and flows toward the exhaust port.

[0016] In addition, at the time of full water spraying in the summer, in the center finned pipe, the spray water, which has itself heated by cooling the circulating cooling water indirectly, comes into direct contact with the air via the fins and the latent heat of vaporization. And cooled.

According to the third aspect of the present invention, the operation unique to the invention is as follows.
The partition plate prevents the spray water from flowing between the heat exchange portions on both sides and the central portion, and generates a predetermined amount of dry air.

[0018]

Next, typical embodiments of the present invention will be described. Embodiment 1 A typical embodiment of the invention described in claims 1 and 2,
In FIG. 1, A is a cross-flow cooling tower having a function to prevent white smoke, and several hermetically sealed heat exchangers B are arranged below the upper water tank 10 in an upper and lower hierarchy. The supply end of the common supply header 12 on the exhaust port 11 side
The discharge ends are connected to a common discharge header 14 on the outside air intake 13 side. The upper water tank 10 is divided into three sprinkling portions 10a, 10b, and 10c in the width direction of the outside air intake 13. These hermetic heat exchangers B are provided with the respective water sprinkling portions 10a,
c, at least three heat exchange parts B1, B2,
B3 is partitioned in the width direction of the outside air intake 13, and supply pipes 15 for supplying spray water to the water spray portions 10a, 10b, 10c are respectively provided with open / close valves 16a, 16b, 1
6c is provided. Each of the closed heat exchangers B of each stage is composed of one cooling coil. Of the three heat exchange portions B1, B2, and B3 arranged in the width direction, the central heat exchange portion B2 is connected to the finned tube 20 from the finned tube 20. The heat exchange portions B1 and B3 on both sides are formed by interposing a filler plate 28 made of synthetic resin between the bare tubes 21 vertically adjacent to each other (see FIGS. 1, 2 and 3). Above the mixing chamber where the humid air and the dry air discharged from the heat exchanger B are mixed, the waste port 11 is provided similarly to a known one (see FIG. 1).

Embodiment 2 This is a typical embodiment of the invention described in claim 3, and Embodiment 1
The difference is that, among the three heat exchange portions B10, B20, B30 in one cooling coil, the partition plate 26 perpendicular to the boundary between the heat exchange portions B10, B30 on both sides thereof and the central heat exchange portion B20. It is interposed (see FIG. 4). In addition, the same reference numerals as those in the first embodiment denote the same configuration and operation. The operation of each of the above embodiments is the same as the operation of the invention described in the corresponding claims, and thus the description thereof will be omitted.

[0020]

The effects of the present invention constructed and operated as described above are as follows. In the specific invention according to claim 1, the upper water tank is divided into at least three watering portions in a width direction of the outside air intake, and these closed heat exchangers are provided with at least three heat exchange portions corresponding to the watering portions. Parts are partitioned in the width direction of the outside air intake, and each supply pipe for supplying water to each watering part is provided with an opening / closing valve, so by appropriately selecting watering from the watering part, The amount of air heating can be greatly changed, the amount of dry air generated is adjusted, and in the depth direction of the closed type heat exchanger, the humid air and dry air flow to the exhaust port side without mixing as a parallel flow, and The wet air and the dry air are mixed with each other in the mixing chamber below, and the mixed flow rises toward the exhaust port. Evacuated to the atmosphere in the non-supersaturated state, it is possible to prevent the occurrence of white smoke. That is, in the severe cooling period during the winter operation of the cross-flow cooling tower, during the humid and rainy season during the rainy season, the sprinkling area of the sprinkling part in the upper water tank divided into at least three sprinkling parts in the width direction of the outside air intake is changed. By reducing this, a large amount of dry air is generated, and the humid air and the dry air are discharged into a mixing chamber below the exhaust port without being mixed as a parallel flow, and the humid air and the dry air are discharged from the mixing chamber. Mix with each other, raise the mixed stream to the exhaust port, discharge the air stream from the exhaust port as a whole with high temperature and low humidity, exhaust it to the atmosphere in a non-supersaturated state, and effectively extinguish white smoke from this exhaust port be able to.

According to the second aspect of the present invention, in addition to the effects of the specific invention, the structure of the heat exchanger can be simplified by configuring each of the closed heat exchangers with one cooling coil. By using a finned pipe at the center heat exchange part, a part of the circulating water scattered from the heat exchange parts on both sides is prevented from entering the central heat exchange part by the fins provided on the finned pipe. can do. As a result, a predetermined amount of dry air can be generated from the central heat exchange portion.

According to the third aspect of the present invention, in addition to having the same effect as the first aspect of the present invention, a vertical partition plate is provided at the boundary between the heat exchange portions on both sides and the central heat exchange portion. This prevents spray water from flowing between the heat exchange part on both sides and the central heat exchange part, prevents part of the circulating spray water from entering the dry air generation part, and ensures a certain amount of dry air. And the generation of white smoke can be more reliably prevented, and the structure of the sealed heat exchanger can be simplified.

[Brief description of the drawings]

FIG. 1 is a schematic side view of a cooling tower according to a first embodiment.

FIG. 2 is a schematic side view of a main part viewed from the outside air intake side of FIG. 1;

FIG. 3 is a schematic plan view of a main part of FIG. 2;

FIG. 4 is a schematic side view of a cooling tower according to a second embodiment.

[Explanation of symbols]

 10a, 10b, 10c Watering part B1, B2, B3 Heat exchange part 16a, 16b, 16c On-off valve

Claims (3)

(57) [Claims] 1. A closed heat exchanger is arranged below the upper water tank in an upper and lower hierarchy, and the supply ends of these closed heat exchangers are connected to a common supply header on the exhaust port side and the discharge end thereof. Are cross-flow cooling towers each connected to a common discharge header on the outside air intake side, wherein the upper water tank is divided into at least three watering portions in the width direction of the outside air intake port, and these closed heat exchangers are At least three heat exchange portions are defined in the width direction of the outside air intake port corresponding to the respective water spray portions, and supply pipes for supplying spray water to each water spray portion are provided with on-off valves. A cross-flow cooling tower with a characteristic white smoke prevention function. 2. The upper water tank is divided into three water sprinkling portions in the width direction of the outside air intake of the cross-flow cooling tower, and each hermetically sealed heat exchanger in each of the stages comprises one cooling coil. The closed type heat exchanger is divided into three heat exchange portions corresponding to the respective water sprinkling portions, and a central heat exchange portion of the three heat exchange portions is formed by a finned tube. The cross-flow cooling tower with white smoke prevention function according to claim 1. 3. A white plate according to claim 1, wherein a vertical partition plate is provided at a boundary between the heat exchange portions on both sides of the three heat exchange portions and a central heat exchange portion. Crossflow cooling tower with smoke prevention function.