JP2014153001A - Cooling tower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling tower that does not require running cost and has high heat exchange efficiency.SOLUTION: A fan driving water turbine located at a tower top portion is rotated by cooled water, and by using the rotating force, a fan is rotated. This configuration eliminates the necessity of running cost for driving the fan. A water spray tank having a bottom plate with a plurality of water spray holes is installed at the tower top portion, and a plurality of water running rods for allowing the cooled water having passed through the water spray holes to run down are hung on portions between the respective water spray holes of the bottom plate. Thus heat exchange efficiency between outside air and the cooled water can be enhanced without using a filler unit.

Description

  The present invention relates to a cooling tower, and more particularly to a high place dropping type cooling tower that generates an upward air flow in the tower space and exchanges heat between the cooling water falling from the top of the tower and the rising air.

  For example, in a geothermal power generation plant, a well is excavated, geothermal steam heated by underground magma is guided to the ground, and power is generated by rotating a turbine of a generator using this steam as a working fluid. Steam discharged from the turbine (turbine exhaust) is introduced into a condenser in a high vacuum state, where it is cooled by cooling water from the cooling tower and becomes hot water (cooled water) around 80 ° C. The hot water is then pumped to the cooling tower by a circulation pump (lift pump), where it is cooled to around 40 ° C. by heat exchange with the outside air, and returned to the condenser again as cooling water for use in condensing the turbine exhaust. Has been.

  As such a cooling tower, for example, a high place falling type disclosed in Patent Document 1, for example, is known. The cooling tower of Patent Document 1 is provided with an air suction portion on the side wall, and the outside air is sucked from the suction portion into the tower internal space by the rotation of an electric fan installed at the top of the cooling tower. After that, the hot water sent to the cooling tower is sprinkled from above in the space inside the tower and dropped, cooled by exchanging heat with the outside air taken in from the suction section, and then cooled from the water storage tank at the bottom of the cooling tower. It is recovered as water.

JP-A-6-137260

However, in the cooling tower disclosed in Patent Document 1, by rotating an electric fan at the top of the tower, outside air is sucked from the suction part on the side wall to generate an updraft. For this reason, electric power for operating the electric fan is required during operation of the cooling tower, and running costs are incurred.
Further, as another cooling tower installed in a factory plant or the like, for example, one in which a filler unit for increasing a heat exchange rate is accommodated in a space in the tower. In this cooling tower, the hot water from the top of the tower does not fall directly into the water tank at the bottom of the tower as in Patent Document 1, but the hot water is caught by the filler unit in the middle of the tower space, It allows heat exchange with the outside air for a long time while passing down the surface of the material. A heat exchange rate increases by the mutual contact time becoming long. However, the filler unit is easily clogged with foreign substances between the fillers, and maintenance is troublesome. After a certain period, the filler unit must be replaced with a new filler unit.

  Therefore, as a result of intensive research, the inventor installed a fan-driven water turbine at the top of the tower, rotated this with water to be cooled, and configured to rotate the fan with the rotational force. Has been found to be unnecessary. In addition, a watering tank having a plurality of water spray holes provided on the bottom plate is provided at the top of the tower, and a plurality of water transfer members that carry down the water to be cooled that has passed through the water spray holes are suspended from the back surface of the bottom plate. The inventors have found that the heat exchange rate between the outside air and the water to be cooled can be increased without using the above-described filler unit, and the present invention has been completed.

  An object of the present invention is to provide a cooling tower that does not require running cost and has high heat exchange efficiency.

  The invention according to claim 1 is a tower casing in which a plurality of outside air intakes are formed on an outer peripheral wall, a lifting pump for raising cooling water to the tower top of the tower casing, and a tower top of the tower casing A water tank for receiving the water to be cooled that has been lifted and lifted, and for allowing the water to be cooled to flow into the space in the tower through a plurality of water holes formed apart from the bottom plate, A plurality of water transfer members suspended in a portion between the adjacent water sprinkling holes and passing along the outer peripheral surface of the water to be cooled passing through the water sprinkling holes, and an upper end portion opened to the bottom plate. A perforated cylinder suspended in a state penetrating the upper and lower surfaces of the bottom plate and having a large number of vent holes formed over its entire length, and a fan rotation shaft extending in the length direction of the perforated cylinder in the perforated cylinder And a fan stored in a rotatable manner around the water tank A fan-driven water turbine that rotates about the turbine rotation shaft by the water to be cooled that is provided and lifted by the lifting pump, and a rotation that transmits the rotational force of the turbine rotation shaft to the fan rotation shaft A cooling tower having a force transmission structure.

According to the first aspect of the present invention, the fan driving turbine at the top of the tower is rotated by the water to be cooled lifted by the lifting pump, and the rotational force of the rotating shaft of the turbine is transmitted to the rotational force transmitting structure. The fan is rotated by transmitting to the fan rotation shaft in the perforated cylinder. Thereby, outside air is taken in into the space in a tower from each outside air intake port of the outer peripheral wall of a tower casing via each vent of a perforated pipe. Thus, since it was configured to rotate the fan using the energy of the water to be cooled lifted by the lift pump, the power for driving the fan, which was necessary in the case of the conventional tower, is not required, As a result, the running cost for driving the fan becomes unnecessary.
In addition, the water to be cooled by rotating the fan-driven water turbine is received by the watering tank, and the water to be cooled flowing down to the space in the tower through each watering hole of the bottom plate is formed between the adjacent watering holes and watering holes in the bottom plate. It moves down along the outer peripheral surfaces of a plurality of water transfer members suspended in the middle. At this time, the operation of the fan makes it possible to exchange heat for a long time between the outside air intakes of the outer wall of the tower casing and the outside air taken into the tower space, for example, compared to when the tower space is dropped directly. It can be carried out. Thereby, even if it does not use the filler unit of another conventional tower mentioned above, the heat exchange efficiency (cooling efficiency of to-be-cooled water) with external air and to-be-cooled water can be improved.

As a cooling tower, what cools the warm water (cooled water) discharged | emitted from condensers, such as a geothermal power plant and a thermal power plant, is employable, for example. In addition, cooling towers installed in various factory plants can be employed.
The shape of the tower casing is arbitrary. For example, a cylindrical shape or a rectangular shape can be employed.
The outside air intake port may be formed in the whole area of the outer peripheral wall of the tower casing, or may be formed in a part thereof.
Water to be cooled is selected according to the facility where the cooling tower is installed. For example, hot water discharged from a condenser of a geothermal power plant.
As the lifting pump, a general pump used for pumping water can be adopted.
The size and shape of the watering tank are arbitrary. Generally, it is the same size and shape as the top of the tower casing in plan view. The diameter of the water spray holes is preferably set to 5 to 30 mm so that the flow of the water to be cooled to the water transfer member suspended on the lower surface (lower side) of the bottom plate becomes smooth. If it is less than 5 mm, the watering holes are likely to be clogged with impurities (foreign matter). Moreover, if it exceeds 30 mm, the to-be-cooled water which passed the sprinkling hole will fall to the direct bottom as a water flow, without moving to the water transfer member along the back surface of the bottom plate of a sprinkling tank.

As the material for the water transfer member and the porous cylinder, it is possible to employ stainless steel that does not easily rust. In addition, a synthetic resin may be used.
As the water transfer member, for example, a bar, a cylinder, a plate, a wire, a rope, a string, or the like can be used. In the case of a bar, as a cross-sectional shape orthogonal to the length direction, for example, a circle, a semicircle, a quarter circle, an ellipse, a triangle, a polygon more than a quadrangle (including a square), and the like can be adopted. it can. Among these, a semicircle, a quarter circle, and a strip shape are preferable.
The lengths of the water transfer member and the porous tube are arbitrary. For example, it may be substantially the same length as the tower casing.
The maximum width of the water transfer member is arbitrary. However, 20-40 mm is preferable.
The outer peripheral surface of the water transfer member may be coated with a hydrophilic coating film or a non-hydrophilic coating film according to the degree of fluidity of the water to be cooled.

As the external shape of the porous tube, for example, a cylinder, a square tube, or the like can be adopted.
The inner diameter of the porous cylinder is 100 mm or more. If it is less than 100 mm, the fan accommodated in the cylinder becomes too small, and the outside air cannot be sufficiently taken into the space in the tower from each outside air intake port.
The diameter of the vent is 10-30 mm. If it is less than 10 mm, the intake air is insufficient, and if it exceeds 30 mm, part of the water to be cooled that has flowed into the space in the tower through the sprinkling holes easily enters the porous cylinder through the vent holes.
As the fan, for example, various propeller fans can be adopted. It is preferable that the outer diameter of the fan be approximately the same as the inner diameter of the porous cylinder because the suction force (negative pressure) of the outside air into the porous cylinder can be maximized.

The installation position of the fan in the cylinder of the porous cylinder is arbitrary. For example, it may be in the upper end of the perforated tube, in the middle of the perforated tube, or in the lower end of the perforated tube.
The fan rotation shaft is arranged such that its axial direction is in the length direction of the porous tube. The upper end portion of the fan rotation shaft may protrude upward from the upper opening of the perforated tube. This is easier to connect with the rotational force transmission structure. The fan rotation shaft may be long, and a plurality of fans may be arranged in multiple stages at a constant pitch in the length direction of the fan rotation shaft.
The type of water turbine for driving the fan is arbitrary. For example, a propeller turbine, a Berton turbine, a Francis turbine, etc. can be employed in addition to the open top turbine. The length of the water turbine rotating shaft may be horizontal or vertical.
As the rotational force transmission structure, for example, a gear system including a bevel gear, a chain / sprocket system, a belt / pulley system, a link direction, or the like can be employed.

  According to a second aspect of the present invention, the plurality of outside air intake ports are formed at a constant vertical and horizontal pitch over the entire outer peripheral wall of the tower casing, and the porous cylinder is suspended from a central portion of the bottom plate. The water transfer member is the cooling tower according to claim 1, wherein the water transfer member is suspended from the entire area of the bottom plate.

  According to the second aspect of the present invention, when the fan is operated, the outside air is taken into the space in the tower from the entire outer peripheral wall of the porous tube through each outside air intake port. Thereafter, the outside air exchanges heat with the water to be cooled that flows down the outer peripheral surface of each water transfer member while moving toward the perforated tube suspended in the center of the bottom plate. Thereby, in all the water transfer members arranged around the perforated tube, the hot water flowing down the rod can be uniformly and sufficiently cooled.

According to the first aspect of the present invention, the fan-driven water turbine is rotated by the water to be cooled that has been raised to the top of the tower by the lift pump, and the rotational force thereof is perforated by using the rotational force transmission structure. The fan is rotated by transmitting to the fan rotation shaft inside. Since it comprised in this way, the electric power for a fan drive required in the case of the conventional tower becomes unnecessary, As a result, the running cost for a fan drive does not start.
In addition, the water to be cooled by rotating the fan-driven water turbine is received by the watering tank, and the water to be cooled flowing down to the space in the tower through each watering hole of the bottom plate is formed between the adjacent watering holes and watering holes in the bottom plate. It moves down along the outer peripheral surfaces of a plurality of water transfer members suspended in the middle. At this time, the operation of the fan makes it possible to exchange heat for a long time between the outside air intakes of the outer wall of the tower casing and the outside air taken into the tower space, for example, compared to when the tower space is dropped directly. It can be carried out. Thereby, even if it does not use the filler unit of another conventional tower mentioned above, the cooling efficiency of to-be-cooled water can be improved.

  In particular, according to the second aspect of the present invention, when the fan is operated, the outside air is taken into the space in the tower from the entire outer peripheral wall of the porous tube through each outside air intake port. Thereafter, the outside air exchanges heat with the water to be cooled that flows down the outer peripheral surface of each water transfer member while moving toward the perforated tube suspended in the center of the bottom plate. Thereby, in all the water transfer members arranged around the perforated tube, the hot water flowing down the rod can be uniformly and sufficiently cooled.

It is a longitudinal cross-sectional view of the cooling tower which concerns on Example 1 of this invention. It is an enlarged plan view including the partial cross section figure of the cooling tower which concerns on Example 1 of this invention. It is a principal part expanded vertical sectional view of the tower top part of the cooling tower which concerns on Example 1 of this invention. It is an expanded sectional view of the watering tank arrange | positioned at the tower top part of the cooling tower which concerns on Example 1 of this invention. It is a partially expanded front view which shows the flow of the air in the tower space of the cooling tower which concerns on Example 1 of this invention.

  Examples of the present invention will be specifically described below. Here, a cooling tower of a geothermal power plant will be described.

  1 to 3, reference numeral 10 denotes a cooling tower according to the first embodiment of the present invention. The cooling tower 10 includes an outer tower casing 13 in which a plurality of outside air intakes 12 are formed on the outer peripheral wall 11, and an outer tower casing 13. The lift pump P that lifts hot water (cooled water) to the top of the tower and the tower top of the outer tower casing 13 receive the lifted hot water and are spaced apart from the bottom plate 14. It is suspended in the part between the watering tank 16 made to flow down to the space in a tower through several watering holes 15, and the adjacent watering holes 15 among the bottom plates 14, and the warm water which passed through each watering hole 15 is followed along an outer peripheral surface. A plurality of water transfer members 17 that pass down, a porous cylinder 19 in which the upper end of the bottom plate 14 is suspended through the upper and lower surfaces of the bottom plate 14 and a plurality of vent holes 18 are formed over the entire length; In the cylinder of the porous cylinder 19, the length direction of the porous cylinder 19 The fan 21 housed rotatably around the extended fan rotation shaft 20 and the hot water pumped by the lifting pump P and rotated by the water pump 16 rotate around the turbine rotation shaft 28. A high place for a geothermal power plant including a fan driving turbine 22 and a rotational force transmission structure 23 that transmits the rotational force of a turbine rotating shaft 28 of the fan driving turbine 22 to the fan rotating shaft 20 of the fan 21. It is a drop type cooling tower.

Hereinafter, these components will be specifically described.
The outer casing 13 is a square-shaped casing having a side length of 1.5 m and a height of 8 m in plan view, and is a concrete water tank 24 provided by excavating the ground. It is erected inside. When the hot water pumped up by the lifting pump P is caused to flow down and the fan-driven water turbine 22 is rotated at the top of the outer casing 13, a square shape is obtained in plan view so that the hot water does not scatter outside the tower. A shielding wall 25 is erected. A plurality of outside air intakes 12 are formed in the entire outer peripheral wall 11 of the outer tower casing 13 at a constant vertical and horizontal pitch.
The lifting pump P is installed near the cooling tower 10 and lifts up to about 80 ° C. hot water derived from the condenser of the geothermal power plant to the top of the cooling tower 10 via the lifting pipe 26. . The upper end portion 26a of the lifting pipe 26 is bent horizontally above the tower top portion, and the opening tip thereof is disposed immediately above the fan driving turbine 22. As a result, the hot water that has flowed down from the tip of the lifting pipe 26 continuously collides with each blade 22a of the fan driving turbine 22 directly below it, and rotates the fan driving turbine 22 about the turbine rotating shaft 28. Let

The water sprinkling tank 16 is a square water tank mounted on the top of the outer tower casing 13 in plan view, and is supported by a pair of H-shaped steels 41 that are horizontally mounted parallel to the upper end opening of the outer tower casing 13. . Sprinkling holes 15 having a diameter of 2 cm are arranged in a matrix at a constant vertical and horizontal pitch over substantially the entire area of the bottom plate 14 of the watering tank 16. At the center of the bottom plate 14, the upper end portion of the perforated tube 19 with the length direction oriented in the vertical direction is fixed.
Each water transfer member 17 is a bar having a semicircular cross section perpendicular to the length direction, and the upper ends of the water transfer members 17 are fixed to the bottom plate 14 between the adjacent water spray holes 15 in the entire back surface of the bottom plate 14. It is suspended in a state. Each water transfer member 17 has a diameter (maximum width) of 25 mm and a length of about 7 m. The lower end of each water transfer member 17 is disposed near the water storage tank 24.
The porous cylinder 19 has an inner diameter of 20 cm, a length of about 7 m, and a large number of vent holes 18 having a diameter of 3 cm are formed in the entire area of the peripheral wall excluding its upper end. Thereby, the outside air taken into the tower space from the outside air inlets 12 of all the outer peripheral walls 11 can be introduced into the porous cylinder 19 from any height position of the outer tower casing 13.
A frustoconical (substantially umbrella-shaped) water avoidance guide member 40 is disposed on the outer peripheral surface of the porous cylinder 19 immediately above the storage area of each fan 21.

The fan 21 is a propeller fan and is arranged in multiple stages in the in-cylinder space of the porous cylinder 19. That is, the plurality of fans 21 may be arranged only in the upper end portion of the porous cylinder 19 where the vent hole 18 does not exist, or may be arranged over the entire length of the porous cylinder 19 (here, the former). In any case, a plurality of fans 21 are fixed at a constant pitch in the length direction of the fan rotation shaft 20 with respect to the corresponding fan rotation shaft 20. As a result, the negative pressure generated by the operation of the fan 21 reaches the entire area of the porous cylinder 19 in the length direction. The fan rotation shaft 20 of the fan 21 is pivotally supported by a bearing 27 fixed to the upper end portion of the porous cylinder 19 by a cross frame. The upper end portion of the fan rotation shaft 20 of the fan 21 passes through the opening on the upper side of the porous cylinder 19 and is disposed in the vicinity of the turbine rotation shaft 28 of the fan driving water turbine 22. A small-diameter driven bevel gear 29 having a small diameter is fixed to the upper end of the fan rotation shaft 20 of the fan 21.
The fan-driven water turbine 22 is an open top-type water turbine in which the water turbine rotating shaft 28 is horizontal, and is disposed above one side of the sprinkler tank 16. A base portion of the water turbine rotating shaft 28 is cantilevered via a bearing 31 at an upper end portion of a water turbine support base 30 erected along one side wall of the water sprinkling tank 16. Further, the tip end portion of the water turbine rotating shaft 28 passes through the central portion of the fan driving water turbine 22 and reaches near the upper portion of the porous tube 19. A large-diameter drive-side bevel gear 32 that meshes with the driven-side bevel gear 29 is fixed to the tip of the water turbine rotating shaft 28. The rotational force transmission structure 23 includes the driving side bevel gear 32 and the driven side bevel gear 29.

Next, with reference to FIGS. 1-5, the operating method of the cooling tower 10 which concerns on Example 1 of this invention is demonstrated.
As shown in FIGS. 1 to 3, the cooling tower 10 is installed in a geothermal power plant. In a geothermal power plant, a well is excavated, geothermal steam heated by underground magma is guided to the ground, and power is generated by rotating a turbine of a generator using this steam as a working fluid. At that time, the turbine exhaust discharged from the turbine is introduced into a condenser in a high vacuum state, where it is cooled by cooling water from the cooling tower 10 and becomes hot water at around 80 ° C. Thereafter, the hot water is pumped to the cooling tower 10 by the lifting pump P.

  That is, the hot water raised to the top of the tower by the lifting pump P flows down from the opening at the tip of the lifting pipe 26 and rotates the fan-driven turbine 22. The rotational force is transmitted from the water turbine rotating shaft 28 to the fan rotating shaft 20 through the driving side bevel gear 32 and the driven side bevel gear 29, and the fan 21 rotates. Thereby, the in-cylinder space of the porous cylinder 19 becomes negative pressure, and as a result, the inner space of the outer tower casing 13 becomes negative pressure, and accordingly, from each outside air intake port 12 of the outer peripheral wall 11 of the outer tower casing 13. Outside air is taken into the tower space. Thus, since the fan 21 is rotated using the potential energy of the hot water raised by the lifting pump P, the electric power for driving the fan, which was necessary in the conventional tower, becomes unnecessary. There is no running cost.

Moreover, since the hot water after rotating the fan driving water wheel 22 is accumulated in the watering tank 16 and the diameter of each watering hole 15 of the bottom plate 14 is as small as 2 cm, the hot water flowing into the tower space through each watering hole 15 is It passes along the back surface of the bottom plate 14 and moves to each water transfer member 17 suspended in a portion between the adjacent water spray holes 15 (FIG. 4). Thereafter, the warm water slowly moves down along the outer peripheral surface of each water transfer member 17. At this time, since the fan 21 is operating, the outside air taken into the space in the tower from each outside air inlet 12 of the outer peripheral wall 11 of the outer tower casing 13 exchanges heat with the hot water that has been transferred down (FIG. 5). That is, since the hot water contacts the outside air while moving downward on the outer peripheral surface of each water transfer member 17 at a low speed, for example, the hot water is directly directed vertically from the water spray hole 15 toward the water storage tank 24 as in the prior art. Compared to dropping, the time for heat exchange becomes longer. Thereby, even if it does not use the filler unit of another conventional tower mentioned above, the cooling efficiency of to-be-cooled water can be improved.
At that time, since the water avoidance guide member 40 is disposed on the outer peripheral surface of the perforated tube 19 in the portion directly above the storage area of each fan 21, the splash of hot water falling from each water spray hole 15 is avoided. It collides with the guide member 40 and moves away from the porous cylinder 19. As a result, it is possible to prevent hot water splashes and the like from being sucked into the porous cylinder 19 by the negative pressure of the fan 21 and a large amount of hot water from being applied to the fan 21. The water avoidance guide member 40 is particularly effective because the hot water is easily rusted when the hot water is hot spring water having high acidity.

Furthermore, a plurality of outside air inlets 12 are formed at a constant vertical and horizontal pitch in the entire outer peripheral wall 11 of the tower casing 13, a porous cylinder 19 is suspended at the center of the bottom plate 14, and a plurality of water transfer members 17 are provided. Since the fan 21 is operated so as to be hung apart from the whole area of the bottom plate 14, outside air can be taken into the space in the tower from the whole area of the outer peripheral wall 11 of the porous cylinder 19 through each outside air inlet 12. Thereafter, the outside air moves toward the porous cylinder 19 suspended in the central portion of the bottom plate 14, and on the way, hot water that flows down the outer peripheral surface of each water transfer member 17 arranged around the porous cylinder 19 and Heat exchange between each. Thereby, in all the water transfer members 17 suspended around the porous cylinder 19, the hot water flowing down the rod can be uniformly and sufficiently cooled.
After the heat exchange, the cooling water (warm water) cooled to around 40 ° C. is dropped into the water storage tank 24 from the lower end of each water transfer member 17 and then temporarily stored, and then returned to the condenser again as cooling water. Used for condensation of turbine exhaust.

  The present invention is useful as a cooling tower technique that is economical and has high heat exchange efficiency with the outside air of the water to be cooled.

10 Cooling tower,
11 outer wall,
12 Outside air intake,
13 tower casing,
14 Bottom plate,
15 sprinkling holes,
16 Watering tank,
17 Water transport members,
18 vents,
19 perforated tube,
20 Fan rotation axis,
21 fans,
22 Fan-driven water wheel,
23 Rotational force transmission structure,
28 water turbine rotating shaft,
P Lift pump.

  The present invention relates to a cooling tower, and more particularly to a high place dropping type cooling tower that generates an upward air flow in the tower space and exchanges heat between the cooling water falling from the top of the tower and the rising air.

  For example, in a geothermal power generation plant, a well is excavated, geothermal steam heated by underground magma is guided to the ground, and power is generated by rotating a turbine of a generator using this steam as a working fluid. Steam discharged from the turbine (turbine exhaust) is introduced into a condenser in a high vacuum state, where it is cooled by cooling water from the cooling tower and becomes hot water (cooled water) around 80 ° C. The hot water is then pumped to the cooling tower by a circulation pump (lift pump), where it is cooled to around 40 ° C. by heat exchange with the outside air, and returned to the condenser again as cooling water for use in condensing the turbine exhaust. Has been.

  As such a cooling tower, for example, a high place falling type disclosed in Patent Document 1, for example, is known. The cooling tower of Patent Document 1 is provided with an air suction portion on the side wall, and the outside air is sucked from the suction portion into the tower internal space by the rotation of an electric fan installed at the top of the cooling tower. After that, the hot water sent to the cooling tower is sprinkled from above in the space inside the tower and dropped, cooled by exchanging heat with the outside air taken in from the suction section, and then cooled from the water storage tank at the bottom of the cooling tower. It is recovered as water.

JP-A-6-137260

However, in the cooling tower disclosed in Patent Document 1, by rotating an electric fan at the top of the tower, outside air is sucked from the suction part on the side wall to generate an updraft. For this reason, electric power for operating the electric fan is required during operation of the cooling tower, and running costs are incurred.
Further, as another cooling tower installed in a factory plant or the like, for example, one in which a filler unit for increasing a heat exchange rate is accommodated in a space in the tower. In this cooling tower, the hot water from the top of the tower does not fall directly into the water tank at the bottom of the tower as in Patent Document 1, but the hot water is caught by the filler unit in the middle of the tower space, It allows heat exchange with the outside air for a long time while passing down the surface of the material. A heat exchange rate increases by the mutual contact time becoming long. However, the filler unit is easily clogged with foreign substances between the fillers, and maintenance is troublesome. After a certain period, the filler unit must be replaced with a new filler unit.

  Therefore, as a result of intensive research, the inventor installed a fan-driven water turbine at the top of the tower, rotated this with water to be cooled, and configured to rotate the fan with the rotational force. Has been found to be unnecessary. In addition, a watering tank having a plurality of water spray holes provided on the bottom plate is provided at the top of the tower, and a plurality of water transfer members that carry down the water to be cooled that has passed through the water spray holes are suspended from the back surface of the bottom plate. The inventors have found that the heat exchange rate between the outside air and the water to be cooled can be increased without using the above-described filler unit, and the present invention has been completed.

  An object of the present invention is to provide a cooling tower that does not require running cost and has high heat exchange efficiency.

The invention according to claim 1 is a tower casing in which a plurality of outside air intake ports are formed on an outer peripheral wall, a lifting pump for raising cooling water to the top of the tower casing, and a tower of the tower casing It provided at the top, and together with the elevating been subjected to the target coolant, a water tank dispersion to flow down the target cooling water in the space in the tower casing through a plurality of water spray holes formed at a distance from each other in the bottom plate, the column A bar that is suspended in a portion of the bottom plate between adjacent watering holes in a space in the casing , and that transfers the water to be cooled through each watering hole along its outer peripheral surface. A plurality of water-conveying members and a porous member in which a plurality of vent holes are formed over the entire length, suspended in the space in the tower casing, with the upper end opened from the bottom plate penetrating the upper and lower surfaces of the bottom plate. a cylindrical, constant peak in the cylinder of the porous tube In Ji, a plurality of fans which are rotatably accommodated around the fan rotation axis extending in the length direction of the porous tube, provided in the diffuser aquarium, and the cooling is elevating by the elevating pump A cooling tower provided with an overlying fan driving water turbine that rotates about a horizontal water turbine rotating shaft by water, and a rotational force transmission structure that transmits the rotational force of the water turbine rotating shaft to the fan rotating shaft. is there.

According to the first aspect of the present invention, the fan driving turbine at the top of the tower is rotated by the water to be cooled lifted by the lifting pump, and the rotational force of the rotating shaft of the turbine is transmitted to the rotational force transmitting structure. The fan is rotated by transmitting to the fan rotation shaft in the perforated cylinder. Thereby, outside air is taken in into the space in a tower from each outside air intake port of the outer peripheral wall of a tower casing via each vent of a perforated pipe. As described above, the fan is rotated by using the kinetic energy and the potential energy of the water to be cooled lifted by the lift pump, so that the electric power for driving the fan that has been necessary in the case of the conventional tower is used. As a result, the running cost for driving the fan becomes unnecessary.
In addition, the water to be cooled by rotating the fan-driven water turbine is received by the watering tank, and the water to be cooled flowing down to the space in the tower through each watering hole of the bottom plate is formed between the adjacent watering holes and watering holes in the bottom plate. It moves down along the outer peripheral surfaces of a plurality of water transfer members suspended in the middle. At this time, the operation of the fan makes it possible to exchange heat for a long time between the outside air intakes of the outer wall of the tower casing and the outside air taken into the tower space, for example, compared to when the tower space is dropped directly. It can be carried out. Thereby, even if it does not use the filler unit of another conventional tower mentioned above, the heat exchange efficiency (cooling efficiency of to-be-cooled water) with external air and to-be-cooled water can be improved.

As a cooling tower, what cools the warm water (cooled water) discharged | emitted from condensers, such as a geothermal power plant and a thermal power plant, is employable, for example. In addition, cooling towers installed in various factory plants can be employed.
The shape of the tower casing is arbitrary. For example, a cylindrical shape or a rectangular shape can be employed.
The outside air intake port may be formed in the whole area of the outer peripheral wall of the tower casing, or may be formed in a part thereof.
Water to be cooled is selected according to the facility where the cooling tower is installed. For example, hot water discharged from a condenser of a geothermal power plant.
As the lifting pump, a general pump used for pumping water can be adopted.
The size and shape of the watering tank are arbitrary. Generally, it is the same size and shape as the top of the tower casing in plan view. The diameter of the water spray holes is preferably set to 5 to 30 mm so that the flow of the water to be cooled to the water transfer member suspended on the lower surface (lower side) of the bottom plate becomes smooth. If it is less than 5 mm, the watering holes are likely to be clogged with impurities (foreign matter). Moreover, if it exceeds 30 mm, the to-be-cooled water which passed the sprinkling hole will fall to the direct bottom as a water flow, without moving to the water transfer member along the back surface of the bottom plate of a sprinkling tank.

As the material for the water transfer member and the porous cylinder, it is possible to employ stainless steel that does not easily rust. In addition, a synthetic resin may be used.
As the water transfer member, for example, a bar, a cylinder, a plate, a wire, a rope, a string, or the like can be used. In the case of a bar, as a cross-sectional shape orthogonal to the length direction, for example, a circle, a semicircle, a quarter circle, an ellipse, a triangle, a polygon more than a quadrangle (including a square), and the like can be adopted. it can. Among these, a semicircle, a quarter circle, and a strip shape are preferable.
The lengths of the water transfer member and the porous tube are arbitrary. For example, it may be substantially the same length as the tower casing.
The maximum width of the water transfer member is arbitrary. However, 20-40 mm is preferable.
The outer peripheral surface of the water transfer member may be coated with a hydrophilic coating film or a non-hydrophilic coating film according to the degree of fluidity of the water to be cooled.

As the external shape of the porous tube, for example, a cylinder, a square tube, or the like can be adopted.
The inner diameter of the porous cylinder is 100 mm or more. If it is less than 100 mm, the fan accommodated in the cylinder becomes too small, and the outside air cannot be sufficiently taken into the space in the tower from each outside air intake port.
The diameter of the vent is 10-30 mm. If it is less than 10 mm, the intake air is insufficient, and if it exceeds 30 mm, part of the water to be cooled that has flowed into the space in the tower through the sprinkling holes easily enters the porous cylinder through the vent holes.
As the fan, for example, various propeller fans can be adopted. It is preferable that the outer diameter of the fan be approximately the same as the inner diameter of the porous cylinder because the suction force (negative pressure) of the outside air into the porous cylinder can be maximized.

The installation position of the fan in the cylinder of the porous cylinder is arbitrary. For example, it may be in the upper end of the perforated tube, in the middle of the perforated tube, or in the lower end of the perforated tube.
The fan rotation shaft is arranged such that its axial direction is in the length direction of the porous tube. The upper end portion of the fan rotation shaft may protrude upward from the upper opening of the perforated tube. This is easier to connect with the rotational force transmission structure. The fan rotation shaft may be long, and a plurality of fans may be arranged in multiple stages at a constant pitch in the length direction of the fan rotation shaft.
The type of water turbine for driving the fan is arbitrary. For example, a propeller turbine, a Berton turbine, a Francis turbine, etc. can be employed in addition to the open top turbine. The length of the water turbine rotating shaft may be horizontal or vertical.
As the rotational force transmission structure, for example, a gear system including a bevel gear, a chain / sprocket system, a belt / pulley system, a link direction, or the like can be employed.

  According to a second aspect of the present invention, the plurality of outside air intake ports are formed at a constant vertical and horizontal pitch over the entire outer peripheral wall of the tower casing, and the porous cylinder is suspended from a central portion of the bottom plate. The water transfer member is the cooling tower according to claim 1, wherein the water transfer member is suspended from the entire area of the bottom plate.

  According to the second aspect of the present invention, when the fan is operated, the outside air is taken into the space in the tower from the entire outer peripheral wall of the porous tube through each outside air intake port. Thereafter, the outside air exchanges heat with the water to be cooled that flows down the outer peripheral surface of each water transfer member while moving toward the perforated tube suspended in the center of the bottom plate. Thereby, in all the water transfer members arranged around the perforated tube, the hot water flowing down the rod can be uniformly and sufficiently cooled.

According to the first aspect of the present invention, the fan-driven water turbine is rotated by the water to be cooled that has been raised to the top of the tower by the lift pump, and the rotational force thereof is perforated by using the rotational force transmission structure. The fan is rotated by transmitting to the fan rotation shaft inside. Since it comprised in this way, the electric power for a fan drive required in the case of the conventional tower becomes unnecessary, As a result, the running cost for a fan drive does not start.
In addition, the water to be cooled by rotating the fan-driven water turbine is received by the watering tank, and the water to be cooled flowing down to the space in the tower through each watering hole of the bottom plate is formed between the adjacent watering holes and watering holes in the bottom plate. It moves down along the outer peripheral surfaces of a plurality of water transfer members suspended in the middle. At this time, the operation of the fan makes it possible to exchange heat for a long time between the outside air intakes of the outer wall of the tower casing and the outside air taken into the tower space, for example, compared to when the tower space is dropped directly. It can be carried out. Thereby, even if it does not use the filler unit of another conventional tower mentioned above, the cooling efficiency of to-be-cooled water can be improved.

  In particular, according to the second aspect of the present invention, when the fan is operated, the outside air is taken into the space in the tower from the entire outer peripheral wall of the porous tube through each outside air intake port. Thereafter, the outside air exchanges heat with the water to be cooled that flows down the outer peripheral surface of each water transfer member while moving toward the perforated tube suspended in the center of the bottom plate. Thereby, in all the water transfer members arranged around the perforated tube, the hot water flowing down the rod can be uniformly and sufficiently cooled.

It is a longitudinal cross-sectional view of the cooling tower which concerns on Example 1 of this invention. It is an enlarged plan view including the partial cross section figure of the cooling tower which concerns on Example 1 of this invention. It is a principal part expanded vertical sectional view of the tower top part of the cooling tower which concerns on Example 1 of this invention. It is an expanded sectional view of the watering tank arrange | positioned at the tower top part of the cooling tower which concerns on Example 1 of this invention. It is a partially expanded front view which shows the flow of the air in the tower space of the cooling tower which concerns on Example 1 of this invention.

  Examples of the present invention will be specifically described below. Here, a cooling tower of a geothermal power plant will be described.

  1 to 3, reference numeral 10 denotes a cooling tower according to the first embodiment of the present invention. The cooling tower 10 includes an outer tower casing 13 in which a plurality of outside air intakes 12 are formed on the outer peripheral wall 11, and an outer tower casing 13. The lift pump P that lifts hot water (cooled water) to the top of the tower and the tower top of the outer tower casing 13 receive the lifted hot water and are spaced apart from the bottom plate 14. It is suspended in the part between the watering tank 16 made to flow down to the space in a tower through several watering holes 15, and the adjacent watering holes 15 among the bottom plates 14, and the warm water which passed through each watering hole 15 is followed along an outer peripheral surface. A plurality of water transfer members 17 that pass down, a porous cylinder 19 in which the upper end of the bottom plate 14 is suspended through the upper and lower surfaces of the bottom plate 14 and a plurality of vent holes 18 are formed over the entire length; In the cylinder of the porous cylinder 19, the length direction of the porous cylinder 19 The fan 21 housed rotatably around the extended fan rotation shaft 20 and the hot water pumped by the lifting pump P and rotated by the water pump 16 rotate around the turbine rotation shaft 28. A high place for a geothermal power plant including a fan driving turbine 22 and a rotational force transmission structure 23 that transmits the rotational force of a turbine rotating shaft 28 of the fan driving turbine 22 to the fan rotating shaft 20 of the fan 21. It is a drop type cooling tower.

Hereinafter, these components will be specifically described.
The outer casing 13 is a square-shaped casing having a side length of 1.5 m and a height of 8 m in plan view, and is a concrete water tank 24 provided by excavating the ground. It is erected inside. When the hot water pumped up by the lifting pump P is caused to flow down and the fan-driven water turbine 22 is rotated at the top of the outer casing 13, a square shape is obtained in plan view so that the hot water does not scatter outside the tower. A shielding wall 25 is erected. A plurality of outside air intakes 12 are formed in the entire outer peripheral wall 11 of the outer tower casing 13 at a constant vertical and horizontal pitch.
The lifting pump P is installed near the cooling tower 10 and lifts up to about 80 ° C. hot water derived from the condenser of the geothermal power plant to the top of the cooling tower 10 via the lifting pipe 26. . The upper end portion 26a of the lifting pipe 26 is bent horizontally above the tower top portion, and the opening tip thereof is disposed immediately above the fan driving turbine 22. As a result, the hot water that has flowed down from the tip of the lifting pipe 26 continuously collides with each blade 22a of the fan driving turbine 22 directly below it, and rotates the fan driving turbine 22 about the turbine rotating shaft 28. Let

The water sprinkling tank 16 is a square water tank mounted on the top of the outer tower casing 13 in plan view, and is supported by a pair of H-shaped steels 41 that are horizontally mounted parallel to the upper end opening of the outer tower casing 13. . Sprinkling holes 15 having a diameter of 2 cm are arranged in a matrix at a constant vertical and horizontal pitch over substantially the entire area of the bottom plate 14 of the watering tank 16. At the center of the bottom plate 14, the upper end portion of the perforated tube 19 with the length direction oriented in the vertical direction is fixed.
Each water transfer member 17 is a bar having a semicircular cross section perpendicular to the length direction, and the upper ends of the water transfer members 17 are fixed to the bottom plate 14 between the adjacent water spray holes 15 in the entire back surface of the bottom plate 14. It is suspended in a state. Each water transfer member 17 has a diameter (maximum width) of 25 mm and a length of about 7 m. The lower end of each water transfer member 17 is disposed near the water storage tank 24.
The porous cylinder 19 has an inner diameter of 20 cm, a length of about 7 m, and a large number of vent holes 18 having a diameter of 3 cm are formed in the entire area of the peripheral wall excluding its upper end. Thereby, the outside air taken into the tower space from the outside air inlets 12 of all the outer peripheral walls 11 can be introduced into the porous cylinder 19 from any height position of the outer tower casing 13.
A frustoconical (substantially umbrella-shaped) water avoidance guide member 40 is disposed on the outer peripheral surface of the porous cylinder 19 immediately above the storage area of each fan 21.

The fan 21 is a propeller fan and is arranged in multiple stages in the in-cylinder space of the porous cylinder 19. That is, the plurality of fans 21 may be arranged only in the upper end portion of the porous cylinder 19 where the vent hole 18 does not exist, or may be arranged over the entire length of the porous cylinder 19 (here, the former). In any case, a plurality of fans 21 are fixed at a constant pitch in the length direction of the fan rotation shaft 20 with respect to the corresponding fan rotation shaft 20. As a result, the negative pressure generated by the operation of the fan 21 reaches the entire area of the porous cylinder 19 in the length direction. The fan rotation shaft 20 of the fan 21 is pivotally supported by a bearing 27 fixed to the upper end portion of the porous cylinder 19 by a cross frame. The upper end portion of the fan rotation shaft 20 of the fan 21 passes through the opening on the upper side of the porous cylinder 19 and is disposed in the vicinity of the turbine rotation shaft 28 of the fan driving water turbine 22. A small-diameter driven bevel gear 29 having a small diameter is fixed to the upper end of the fan rotation shaft 20 of the fan 21.
The fan-driven water turbine 22 is an open top-type water turbine in which the water turbine rotating shaft 28 is horizontal, and is disposed above one side of the sprinkler tank 16. A base portion of the water turbine rotating shaft 28 is cantilevered via a bearing 31 at an upper end portion of a water turbine support base 30 erected along one side wall of the water sprinkling tank 16. Further, the tip end portion of the water turbine rotating shaft 28 passes through the central portion of the fan driving water turbine 22 and reaches near the upper portion of the porous tube 19. A large-diameter drive-side bevel gear 32 that meshes with the driven-side bevel gear 29 is fixed to the tip of the water turbine rotating shaft 28. The rotational force transmission structure 23 includes the driving side bevel gear 32 and the driven side bevel gear 29.

Next, with reference to FIGS. 1-5, the operating method of the cooling tower 10 which concerns on Example 1 of this invention is demonstrated.
As shown in FIGS. 1 to 3, the cooling tower 10 is installed in a geothermal power plant. In a geothermal power plant, a well is excavated, geothermal steam heated by underground magma is guided to the ground, and power is generated by rotating a turbine of a generator using this steam as a working fluid. At that time, the turbine exhaust discharged from the turbine is introduced into a condenser in a high vacuum state, where it is cooled by cooling water from the cooling tower 10 and becomes hot water at around 80 ° C. Thereafter, the hot water is pumped to the cooling tower 10 by the lifting pump P.

  That is, the hot water raised to the top of the tower by the lifting pump P flows down from the opening at the tip of the lifting pipe 26 and rotates the fan-driven turbine 22. The rotational force is transmitted from the water turbine rotating shaft 28 to the fan rotating shaft 20 through the driving side bevel gear 32 and the driven side bevel gear 29, and the fan 21 rotates. Thereby, the in-cylinder space of the porous cylinder 19 becomes negative pressure, and as a result, the inner space of the outer tower casing 13 becomes negative pressure, and accordingly, from each outside air intake port 12 of the outer peripheral wall 11 of the outer tower casing 13. Outside air is taken into the tower space. Thus, since the fan 21 is rotated using the potential energy of the hot water raised by the lifting pump P, the electric power for driving the fan, which was necessary in the conventional tower, becomes unnecessary. There is no running cost.

Moreover, since the hot water after rotating the fan driving water wheel 22 is accumulated in the watering tank 16 and the diameter of each watering hole 15 of the bottom plate 14 is as small as 2 cm, the hot water flowing into the tower space through each watering hole 15 is It passes along the back surface of the bottom plate 14 and moves to each water transfer member 17 suspended in a portion between the adjacent water spray holes 15 (FIG. 4). Thereafter, the warm water slowly moves down along the outer peripheral surface of each water transfer member 17. At this time, since the fan 21 is operating, the outside air taken into the space in the tower from each outside air inlet 12 of the outer peripheral wall 11 of the outer tower casing 13 exchanges heat with the hot water that has been transferred down (FIG. 5). That is, since the hot water contacts the outside air while moving downward on the outer peripheral surface of each water transfer member 17 at a low speed, for example, the hot water is directly directed vertically from the water spray hole 15 toward the water storage tank 24 as in the prior art. Compared to dropping, the time for heat exchange becomes longer. Thereby, even if it does not use the filler unit of another conventional tower mentioned above, the cooling efficiency of to-be-cooled water can be improved.
At that time, since the water avoidance guide member 40 is disposed on the outer peripheral surface of the perforated tube 19 in the portion directly above the storage area of each fan 21, the splash of hot water falling from each water spray hole 15 is avoided. It collides with the guide member 40 and moves away from the porous cylinder 19. As a result, it is possible to prevent hot water splashes and the like from being sucked into the porous cylinder 19 by the negative pressure of the fan 21 and a large amount of hot water from being applied to the fan 21. The water avoidance guide member 40 is particularly effective because the hot water is easily rusted when the hot water is hot spring water having high acidity.

Furthermore, a plurality of outside air inlets 12 are formed at a constant vertical and horizontal pitch in the entire outer peripheral wall 11 of the tower casing 13, a porous cylinder 19 is suspended at the center of the bottom plate 14, and a plurality of water transfer members 17 are provided. Since the fan 21 is operated so as to be hung apart from the whole area of the bottom plate 14, outside air can be taken into the space in the tower from the whole area of the outer peripheral wall 11 of the porous cylinder 19 through each outside air inlet 12. Thereafter, the outside air moves toward the porous cylinder 19 suspended in the central portion of the bottom plate 14, and on the way, hot water that flows down the outer peripheral surface of each water transfer member 17 arranged around the porous cylinder 19 and Heat exchange between each. Thereby, in all the water transfer members 17 suspended around the porous cylinder 19, the hot water flowing down the rod can be uniformly and sufficiently cooled.
After the heat exchange, the cooling water (warm water) cooled to around 40 ° C. is dropped into the water storage tank 24 from the lower end of each water transfer member 17 and then temporarily stored, and then returned to the condenser again as cooling water. Used for condensation of turbine exhaust.

  The present invention is useful as a cooling tower technique that is economical and has high heat exchange efficiency with the outside air of the water to be cooled.

10 Cooling tower,
11 outer wall,
12 Outside air intake,
13 tower casing,
14 Bottom plate,
15 sprinkling holes,
16 Watering tank,
17 Water transport members,
18 vents,
19 perforated tube,
20 Fan rotation axis,
21 fans,
22 Fan-driven water wheel,
23 Rotational force transmission structure,
28 water turbine rotating shaft,
P Lift pump.

Claims (2)

A tower casing in which a plurality of outside air intakes are formed on the outer peripheral wall;
A lifting pump for lifting cooling water to the top of the tower casing;
A sprinkler tank that is provided at the top of the tower casing and that receives the water to be cooled and that causes the water to be cooled to flow into a space in the tower through a plurality of sprinkling holes formed apart from the bottom plate; ,
A plurality of water transfer members that are suspended in a portion of the bottom plate between adjacent water sprinkling holes, and that transfer the water to be cooled through the water sprinkling holes along an outer peripheral surface;
The bottom plate is suspended in a state where the upper end portion that opens through the top and bottom surfaces of the bottom plate, and a plurality of vent holes are formed over the entire length, and
A fan housed in the perforated cylinder so as to be rotatable about a fan rotation axis extending in the length direction of the perforated cylinder;
A fan-driven water turbine that rotates about a water turbine rotating shaft by water to be cooled provided in the watering tank and lifted by the lifting pump;
The cooling tower provided with the rotational force transmission structure which transmits the rotational force of the said water turbine rotating shaft to the said fan rotating shaft. The plurality of outside air intakes are formed at a constant vertical and horizontal pitch throughout the outer peripheral wall of the tower casing.
The perforated tube is hung at the center of the bottom plate,
The cooling tower according to claim 1, wherein the plurality of water transfer members are hung apart from each other across the bottom plate.

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