Patent Application
20070284316
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:
Hereinbelow, the present invention will be described in detail by way of embodiments thereof illustrated in the accompanying drawings.
This cooling apparatus includes a cooling tower 1, which is divided into an upper portion 32, an intermediate portion 2, and a lower portion 3.
In the upper portion 32 are provided an annular sprinkle water storage tank 4 for storing cooling water, and a fan 5 placed at a center surrounded by the sprinkle water storage tank 4.
In the intermediate portion 2 are provided sprinkling ports 18 as water sprinkling portions provided at a lower portion of the sprinkle water storage tank 4, a multiplicity of heat exchanger pipes 8 placed below the sprinkling ports 18 and formed from copper into a coil shape, and a louver 7 for prevention of cooling water scattering which is so placed as to surround outsides of the heat exchanger pipes 8 and serve as a side wall of the cooling tower. There is a space in central portion of the intermediate portion 2.
The sprinkling ports 18 are formed as numerous small holes so that cooling water 90 can be sprinkled as evenly as possible to outer peripheral surfaces of the heat exchanger pipes 8. Through those small holes, the cooling water 90 drops so as to be sprinkled to the heat exchanger pipes 8.
In this case, it is assumed that water 80 as a heating medium higher in temperature than outside air is flowing inside the heat exchanger pipes 8.
In the lower portion 3 are provided a main water tank 9 for collecting and storing the cooling water 90 sprinkled by the sprinkling ports 18, and a submerged pump type micro/nanobubble generator 12 placed on a porous plate 15 inside the main water tank 9. Outside the main water tank 9 is provided a sprinkler pump 10 as a first pump portion for sucking the cooling water 90 from a portion of the main water tank 9 below the porous plate 15 and transferring the cooling water 90 to the sprinkle water storage tank 4. The discharge rate of flow of the sprinkler pump 10 can be so set that the circulating water amount for the main water tank 9 becomes 1 rotation per hour.
The porous plate 15 may be formed of either stainless or plastic material without any particular limitations on its material.
At a gas suction portion of the submerged pump type micro/nanobubble generator 12, an ozone generator 35 is integrally fitted via an ozone suction pipe 33 and a valve 34 for regulation of ozone generation amount. These components 12, 33, 34, 35 constitute a micro/nanobubble generation section. The ozone generator 35 may be set to such performance that the concentration of ozone within the main water tank 9 falls within a range of 2 ppm to 5 ppm.
As compared with a common micro/nanobubble generation system composed of a known micro/nanobubble generator (not shown) and a circulating pump (not shown), this micro/nanobubble generation section is simpler in its system and moreover capable of generating larger amounts of micro/nanobubbles on a water stream 13 by virtue of its adoption of the submerged pump type micro/nanobubble generator 12.
It is advantageous for a cooling apparatus that the micro/nanobubble generation section is provided as a simpler system from a management point of view as well.
Further, the submerged pump type micro/nanobubble generator 12 is larger in terms of suction amount for generation of micro/nanobubbles, compared to a common micro/nanobubble generation system composed of a known micro/nanobubble generator (not shown) and a circulating pump (not shown). Therefore, the amount of circulating water becomes larger, preferably.
In operation of the cooling apparatus, the sprinkler pump 10 is driven, so that the cooling water 90 is transferred to the sprinkle water storage tank 4 from a portion of the main water tank 9 below the porous plate 15. The cooling water 90 temporarily stored in the sprinkle water storage tank 4 is sprinkled through the sprinkling ports 18 to the outer peripheral surfaces of the multiplicity of heat exchanger pipes 8. Concurrently with this, the fan 5 set in the upper portion 32 is rotated to make an upward air current. By this rotation of the fan 5, outside air before heat exchange 17 passes through the louver 7 in the intermediate portion 2 so as to be introduced to the zone where the heat exchanger pipes 8 are disposed. The cooling water 90 sprinkled to the outer peripheral surfaces of the heat exchanger pipes 8 absorbs heat from the water 80 within the heat exchanger pipes 8 while being cooled by direct contact with the outside air before heat exchange 17, i.e., with the atmospheric air. Thereafter, the cooling water 90 returns to the main water tank 9. In the way shown above, the cooling water 90 circulates through the upper portion 32, the intermediate portion 2 and the lower portion 3 of the cooling tower. The air, as outside air after heat exchange 6, is discharged upward of the cooling tower 1 by the rotation of the fan 5.
Thus, by the outside air, the water 80 within the heat exchanger pipes 8 is cooled via the cooling water 90.
Along with this, the ozone generator 35 and the submerged pump type micro/nanobubble generator 12 are driven during the operation of the cooling apparatus. As a result, ozone is generated by the ozone generator 35, and ozone micro/nanobubbles are generated in the cooling water 90 with use of the ozone by the micro/nanobubble generator 12. Thus, ozone micro/nanobubbles can be made to be contained in the whole cooling water 90 that circulates through the upper portion 32, the intermediate portion 2 and the lower portion 3 of the cooling tower 1.
It is noted here that the term “micro/nanobubbles” refers to air bubbles having diameters of several hundreds of nm to 10 μm. The term “microbubbles” is defined as “air bubbles which have diameters ranging from 10 μm to several 10's of μm upon their generation.” Microbubbles shrink after their generation to change into “micro/nanobubbles.” A portion of microbubbles go shrinking to finally disappear (completely dissolve). The term “nanobubbles” refers to air bubbles having diameters of several hundreds of nm or less (typically, 100 to 200 nm). The term “micro/nanobubbles” can be explained as bubbles in which microbubbles and nanobubbles are mixed together.
In general, there is a tendency that a long term of operation would cause scale, slime or the like to deposit at wetted portions of the heat exchanger pipes 8, the louver 7 and the like. However, in this cooling apparatus, ozone micro/nanobubbles are contained in the cooling water 90 as described above. Accordingly, with regard to the wetted portions of the cooling water 90, it is effectively achievable i) to suppress occurrence of scale, slime (including that due to microorganisms and algae) and corrosion, ii) in conjunction with this, to reduce water treatment chemicals for the cooling water 90, and iii) to increase the efficiency of heat exchange (thermal efficiency) associated with coils of the cooling tower so that an energy saving can be achieved. That is, it is achievable to keep the cooling water 90 in a desirable state in the cooling tower 1.
In particular, the effect for suppressing the occurrence and deposition of scale, slime and the like can be obtained not only in the heat exchanger pipes 8 and the louver 7 but also in the sprinkle water storage tank 4 of the upper portion 32 and the main water tank 9. As a result, it becomes possible, for example, to greatly reduce the number of times of maintenance for cleaning the small holes 18 of the sprinkle water storage tank 4. It also becomes possible to greatly reduce the number of times of maintenance for cleaning the main water tank 9.
In addition, the submerged pump type micro/nanobubble generator 12 is given in this case by one made by Nomura Electronics Co., Ltd. However, those commercially available may be widely used without limitations on their manufacturers.
The cooling apparatus of the second embodiment differs from that of the first embodiment in that a string-type polyvinylidene chloride material 28 as a microorganism carrier is housed in each of the sprinkle water storage tank 4 and the main water tank 9. Therefore, in
In the cooling apparatus of this second embodiment, the string-type polyvinylidene chloride material 28 having a relatively large surface area is housed in each of the sprinkle water storage tank 4 and the main water tank 9. Therefore, as the operating time elapses, microorganisms propagate only at places in the circulation path of the cooling water 90 where the string-type polyvinylidene chloride material 28 housed in the sprinkle water storage tank 4 and the main water tank 9, respectively, is present. These microorganisms are activated by micro/nanobubbles to produce an effect for subjecting the cooling water 90 to biological water treatment. Accordingly, it becomes possible to reduce water treatment chemicals for the cooling water 90. Also, since the cooling water 90 is subjected to biological water treatment by those microorganisms, it is less likely that algae and slime due to algae occur in the cooling water 90. Thus, decreases in thermal efficiency of the heat exchanger pipes can be prevented, so that an energy saving can be achieved.
In the case of this cooling apparatus, since there is no inflow of waste organic matters unlike the case of waste water treatment, microorganisms propagating in the cooling water 90 are lower in concentration than those of waste water treatment. As a result of such low concentration of microorganisms, microorganisms propagate concentratedly on the string-type polyvinylidene chloride material 28. Then, by the microorganisms that have propagated concentratedly on the string-type polyvinylidene chloride material 28 and been activated by micro/nanobubbles, the water treatment of the cooling water 90 is carried out. As a consequence, the cooling water 90 can be kept in a desirable state in the cooling tower 1, so that deposition of scale and slime can be suppressed.
The cooling apparatus of this third embodiment differs from that of the first embodiment only in that a ring-type polyvinylidene chloride material 29 as a microorganism carrier is housed in each of the sprinkle water storage tank 4 and the main water tank 9. Therefore, in
In the cooling apparatus of this third embodiment, a ring-type polyvinylidene chloride material 29 having a relatively large surface area is housed in each of the sprinkle water storage tank 4 and the main water tank 9. Therefore, as the operating time elapses, microorganisms propagate only at places in the circulation path of the cooling water 90 where the ring-type polyvinylidene chloride material 29 housed in the sprinkle water storage tank 4 and the main water tank 9, respectively, is present. These microorganisms are activated by micro/nanobubbles to produce an effect for subjecting the cooling water 90 to biological water treatment. Accordingly, it becomes possible to reduce water treatment chemicals for the cooling water 90. Also, since the cooling water 90 is subjected to biological water treatment by those microorganisms, it is less likely that algae and slime due to algae occur in the cooling water 90. Thus, decreases in thermal efficiency of the heat exchanger pipes can be prevented, so that an energy saving can be achieved.
In the case of this cooling apparatus, since there is no inflow of waste organic matters unlike the case of waste water treatment, microorganisms propagating in the cooling water 90 are lower in concentration than those of waste water treatment. As a result of such low concentration of microorganisms, microorganisms propagate concentratedly on the ring-type polyvinylidene chloride material 29. Then, by the microorganisms that have propagated concentratedly on the ring-type polyvinylidene chloride material 29 and been activated by micro/nanobubbles, the water treatment of the cooling water 90 is carried out. As a consequence, the cooling water 90 can be kept in a desirable state in the cooling tower 1, so that deposition of scale and slime can be suppressed.
The cooling apparatus of this fourth embodiment differs from that of the first embodiment only in that activated carbon 31 as a microorganism carrier contained in meshed bags 30 is housed in each of the sprinkle water storage tank 4 and the main water tank 9. Therefore, in
In the cooling apparatus of this fourth embodiment, the activated carbon 31 contained in the meshed bags 30 is housed in each of the sprinkle water storage tank 4 and the main water tank 9. Therefore, as the operating time elapses, microorganisms propagate only at places in the circulation path of the cooling water 90 where the activated carbon 31 housed in the sprinkle water storage tank 4 and the main water tank 9, respectively, is present. These microorganisms are activated by micro/nanobubbles to produce an effect for subjecting the cooling water 90 to biological water treatment. In particular, it is a large effect that the activated carbon 31 adsorbs organic matters in the cooling water 90 and allows the adsorbed organic matters to be thereafter decomposed by the microorganisms that have propagated in the activated carbon. Accordingly, it becomes possible to reduce water treatment chemicals for the cooling water 90. Also, since the cooling water 90 is subjected to biological water treatment by those microorganisms, it is less likely that algae and slime due to algae occur in the cooling water 90. Thus, decreases in thermal efficiency of the heat exchanger pipes can be prevented, so that an energy saving can be achieved.
In the case of this cooling apparatus, since there is no inflow of waste organic matters unlike the case of waste water treatment, microorganisms propagating in the cooling water 90 are lower in concentration than those of waste water treatment. As a result of such low concentration of microorganisms, microorganisms propagate concentratedly on the activated carbon 31. Then, by the microorganisms that have propagated concentratedly on the activated carbon 31 and been activated by micro/nanobubbles, the water treatment of the cooling water 90 is carried out. As a consequence, the cooling water 90 can be kept in a desirable state in the cooling tower 1, so that deposition of scale and slime can be suppressed.
In the cooling apparatus of this fifth embodiment, in comparison to the first embodiment, there is provided no submerged pump type micro/nanobubble generator in the main water tank 9, but a water treatment tank 20 as a second auxiliary water tank and a micro/nanobubble generation tank 21 as a first auxiliary water tank are provided outside the cooling tower 1.
In the water treatment tank 20, a string-type polyvinylidene chloride material 28 as a microorganism carrier is housed. Into this water treatment tank 20, the cooling water 90 is introduced from the main water tank 9 through the piping below the main water tank 9 with the flow rate of the cooling water 90 regulated by a valve 19. Thus, the cooling water 90 is stored in the water treatment tank 20. The cooling water 90 of the water treatment tank 20 can be transferred to the micro/nanobubble generation tank 21 through unshown piping.
A submerged pump type micro/nanobubble generator 22 is placed in the micro/nanobubble generation tank 21. At a gas suction portion of the submerged pump type micro/nanobubble generator 22, an ozone generator 35 is integrally fitted via an ozone suction pipe 33 and a valve 34 for regulation of ozone generation amount. These components 22, 33, 34, 35 constitute a micro/nanobubble generation section.
As compared with a common micro/nanobubble generation system composed of a known micro/nanobubble generator (not shown) and a circulating pump (not shown), the micro/nanobubble generation section is simpler in its system and moreover capable of generating larger amounts of micro/nanobubbles on a water stream 23 by virtue of its adoption of the submerged pump type micro/nanobubble generator 22.
Outside the micro/nanobubble generation tank 21 is provided a circulating pump 27 as a second pump portion for sucking the cooling water 90 from the micro/nanobubble generation tank 21 and transferring the cooling water 90 to the main water tank 9 of the cooling tower 1.
In operation of the cooling apparatus, the sprinkler pump 10 is driven, so that the cooling water 90 is transferred from the main water tank 9 to the sprinkle water storage tank 4. The cooling water 90 temporarily stored in the sprinkle water storage tank 4 is sprinkled through the sprinkling ports 18 to the outer peripheral surfaces of the multiplicity of heat exchanger pipes 8. Concurrently with this, the fan 5 set in the upper portion 32 is rotated to make an upward air current. By this rotation of the fan 5, outside air before heat exchange 17 passes through the louver 7 in the intermediate portion 2 so as to be introduced to the zone where the heat exchanger pipes 8 are disposed. The cooling water 90 sprinkled to the outer peripheral surfaces of the heat exchanger pipes 8 absorbs heat from the water 80 within the heat exchanger pipes 8 while being cooled by direct contact with the outside air before heat exchange 17, i.e., with the atmospheric air. Thereafter, the cooling water 90 returns to the main water tank 9. In the way shown above, the cooling water 90 circulates through the upper portion 32, the intermediate portion 2 and the lower portion 3 of the cooling tower. The air, as outside air after heat exchange 6, is discharged upward of the cooling tower 1 by the rotation of the fan 5.
Thus, by the outside air, the water 80 within the heat exchanger pipes 8 is cooled via the cooling water 90.
Along with this, the circulating pump 27 is driven, so that the cooling water 90 of the main water tank 9 in the cooling tower 1 is introduced into the water treatment tank 20 via the valve 19. Then, the cooling water 90 is circulated through the water treatment tank 20, the micro/nanobubble generation tank 21 and the main water tank 9. Therefore, by the submerged pump type micro/nanobubble generator 22 generating ozone micro/nanobubbles in the cooling water 90 of the micro/nanobubble generation tank 21, ozone micro/nanobubbles can be made to be contained in the whole cooling water 90 that circulates along the circulating path through the upper portion 32, the intermediate portion 2 and the lower portion 3 of the cooling tower 1 as well as along the circulation path through the water treatment tank 20, the micro/nanobubble generation tank 21 and the main water tank 9. Thus, the cooling water 90 as a whole can be kept in a desirable state.
Also, the string-type polyvinylidene chloride material 28 as a microorganism carrier is housed in the water treatment tank 20. Therefore, as the operating time elapses, microorganisms propagate only at places in the two circulation paths of the cooling water 90 where the string-type polyvinylidene chloride material 28 housed in the water treatment tank 20 is present. These microorganisms are activated by micro/nanobubbles to produce an effect for subjecting the cooling water 90 to biological water treatment. Accordingly, it becomes possible to reduce water treatment chemicals for the cooling water 90. Also, since the cooling water 90 is subjected to biological water treatment by those microorganisms, it is less likely that algae and slime due to algae occur in the cooling water 90. Thus, decreases in thermal efficiency of the heat exchanger pipes can be prevented, so that an energy saving can be achieved.
The cooling apparatus of this sixth embodiment differs from that of the fifth embodiment only in that a ring-type polyvinylidene chloride material 29 as a microorganism carrier is housed in the water treatment tank 20 instead of the string-type polyvinylidene chloride material 28. Therefore, in
In the cooling apparatus of this sixth embodiment, the ring-type polyvinylidene chloride material 29 as a microorganism carrier is housed in the water treatment tank 20. Therefore, as the operating time elapses, microorganisms propagate only at places in the two circulation paths of the cooling water 90 where the ring-type polyvinylidene chloride material 29 housed in the water treatment tank 20 is present. These microorganisms are activated by micro/nanobubbles to produce an effect for subjecting the cooling water 90 to biological water treatment. Accordingly, it becomes possible to reduce water treatment chemicals for the cooling water 90. Also, since the cooling water 90 is subjected to biological water treatment by those microorganisms, it is less likely that algae and slime due to algae occur in the cooling water 90. Thus, decreases in thermal efficiency of the heat exchanger pipes can be prevented, so that an energy saving can be achieved.
In addition, whether the string-type polyvinylidene chloride material 28 or the ring-type polyvinylidene chloride material 29 is chosen, actually, may be determined depending on treatment experiments.
The cooling apparatus of this seventh embodiment differs from that of the fifth embodiment only in that activated carbon 31 as a microorganism carrier contained in meshed bags 30 is housed in the water treatment tank 20 instead of the string-type polyvinylidene chloride material 28. Therefore, in
In the cooling apparatus of this seventh embodiment, the activated carbon 31 as a microorganism carrier is housed in the water treatment tank 20. Therefore, as the operating time elapses, microorganisms propagate only at places in the two circulation paths of the cooling water 90 where the activated carbon 31 housed in the water treatment tank 20 is present. These microorganisms are activated by micro/nanobubbles to produce an effect for subjecting the cooling water 90 to biological water treatment. In particular, it is a large effect that the activated carbon 31 adsorbs organic matters in the cooling water 90 and allows the adsorbed organic matters to be thereafter decomposed by the microorganisms that have propagated in the activated carbon. Accordingly, it becomes possible to reduce water treatment chemicals for the cooling water 90. Also, since the cooling water 90 is subjected to biological water treatment by those microorganisms, it is less likely that algae and slime due to algae occur in the cooling water 90. Thus, decreases in thermal efficiency of the heat exchanger pipes can be prevented, so that an energy saving can be achieved.
In addition, whether the string-type polyvinylidene chloride material 28 or the activated carbon 31 is chosen, actually, may be determined depending on treatment experiments.
The cooling apparatus of this eighth embodiment differs from that of the first embodiment only in that the ozone generator 35 is replaced with a blower 36. Therefore, in
In the cooling apparatus of this eighth embodiment, since the blower 36 is used instead of the ozone generator 35 of the first embodiment, air micro/nanobubbles are contained in the cooling water 90 in the cooling tower 1. In the case of air micro/nanobubbles, although the bactericidal effect for the cooling water 90 is weak, oxidizability of micro/nanobubbles for the cooling water 90 allows the water quality to be maintained. Also, it is possible to activate the microorganisms propagating in the cooling water 90 to carry out the water treatment for the cooling water 90. Thus, the amount of use of water treatment chemicals can be reduced.
The cooling apparatus of the first embodiment shown in
In that cooling apparatus, the sprinkle water storage tank 4 was set to a capacity of about 0.3 m3, the intermediate portion 2 was set to a capacity of about 4 m3, and the main water tank 9 was set to a capacity of about 1 m3. Also, the sprinkler pump 10 was set to such a discharge rate of flow that the amount of circulating water for the main water tank 9 would be 1 rotation per hour. Further, the ozone generator 35 was set to such performance that the ozone concentration in the main water tank 9 would fall within a range of 2 ppm to 5 ppm. Then, with industrial water introduced as the cooling water 90, the cooling apparatus was subjected to a 1-month trial operation.
After the trial operation, the amount of occurrence of slime was compared between the cooling apparatus and a conventional cooling tower. As a result, the amount of occurrence of slime in the manufactured cooling apparatus was about 20% of that of the conventional cooling tower. Thus, according to the present invention, a preferable result was obtained.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| P2006-158821 | Jun 2006 | JP | national |
