JP2002022253A - Desiccant air conditioning system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To drastically improve the dehumidifying capacity of a desiccant air conditioner in a system comprising the combination of a gas turbine for the generation of electricity used by a cogeneration and the desiccant air conditioner. SOLUTION: High temperature exhaust gas EX from a gas turbine 1 for the generation of electricity is mixed with outer air OA and introduced into the regenerative part 12b of the dehumidifying rotor 12 of a desiccant air conditioner 1. The low humidity and high temperature air, which passes, through the dehumidifying part 12b of the dehumidifying rotor 12, is cooled by a cooling coil 16 and then, used for the cooling load of a room R. Water warmed by the cooling coil 16 is heat exchanged by a water to water heat exchanger with the raw water of a hot-water supply. With this, the warmed raw water is used for the hot-water supply.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a desiccant air-conditioning system, and more particularly to a desiccant air-conditioning system that effectively utilizes exhaust heat from a gas turbine used for power generation.

[0002]

2. Description of the Related Art Conventionally, in a cogeneration system, high-temperature heat generated from a gas turbine for power generation has been recovered and used for other purposes, for example, for air conditioning. In that case, Japanese Patent Application Laid-Open No. 11-351638 discloses that a desiccant air conditioner preferable for the global environment without using Freon is used.

The technology disclosed in this publication is to supply hot water discharged from a gas engine for power generation to a desiccant air conditioner and to cool the desiccant air conditioner during the daytime. The heat of the exhaust gas from the gas engine is once converted to hot water and collected, and the exhaust hot water is passed through a regeneration hot water coil, and the return air from the room to be air-conditioned is heated by the regeneration hot water coil, and the desiccant rotor is heated. And regenerate by evaporating the water in the desiccant rotor.

[0004]

However, as in the prior art described above, the exhaust heat is once recovered with hot water, passed through a hot water coil for regeneration, and then returned to the air-conditioned room and returned to the air conditioner. If heat is supplied to the desiccant rotor by exchanging heat between the hot water coil and the desiccant rotor, the regeneration capacity of the desiccant air conditioner is limited. As a result, there is naturally a limit in improving the dehumidification capacity of the desiccant rotor itself. there were. That is, since the temperature of the hot water passed through the hot water coil for regeneration is at most about 85 ° C. to 90 ° C., there is a limit to the regeneration of the desiccant rotor in the heat regeneration using the hot water coil for regeneration that allows hot water to flow. It was.

The present invention has been made in view of the above points, and in a system in which a gas turbine for power generation and a desiccant air conditioner used in a cogeneration system are combined, the dehumidifying capacity of the desiccant air conditioner is reduced as compared with the conventional one. It is an object of the present invention to provide a desiccant air-conditioning system capable of dramatically increasing the humidity and reducing the humidity to a low humidity which has been impossible in the past, and to solve the above-mentioned problem.

[0006]

According to a first aspect of the present invention, there is provided a power generating gas turbine having a desiccant air conditioner having a dehumidifying rotor having a desiccant. A desiccant air conditioning system is provided, wherein exhaust gas from a gas turbine is introduced into a regeneration section of a dehumidifying rotor of the desiccant air conditioner.

As described above, according to the present invention, the exhaust gas from the gas turbine for power generation is directly introduced into the regeneration section of the dehumidifying rotor of the desiccant air conditioner. After heating by contacting the air and the air, the regenerative ability of the dehumidifying rotor with respect to the regenerating part is improved, and as a result, the dehumidifying ability of the dehumidifying rotor can be greatly improved. Also, the piping around the hot water and the piping around the hot water coil can be omitted, and the exhaust piping is smaller in diameter than the hot water piping, and is preferable in terms of space.

In the present invention, since the exhaust gas of the power generation gas turbine is directly introduced into the regeneration section of the dehumidifying rotor, the power generation gas turbine used is a so-called micro gas turbine. Small gas turbines are suitable. This is because the temperature of the exhaust gas from the gas turbine for power generation is lower in the case of a small gas turbine than in the case of a large gas turbine and is easy to handle. In addition, a small gas turbine is preferable in that it contains few impurities in the exhaust gas.

Therefore, the temperature of the exhaust gas used is 300
Although the temperature around ℃ is suitable, the temperature of the exhaust gas varies depending on the type of gas turbine, and the appropriate value of the temperature of the regeneration air depends on the type of drying agent used in the dehumidifying rotor. It is fixed. For example, the temperature is about 200 ° C. for zeolite. In such a case, it may be used by mixing with the outside air and lowering the temperature to an appropriate temperature.

For example, in the case of a commercially available gas turbine for power generation which is relatively small (power generation output is 28 kW), the temperature of the exhaust gas is about 280 ° C. Therefore, when introducing this exhaust gas into the regeneration section of the dehumidifying rotor using zeolite, it is preferable to mix it with the outside air and lower the temperature to about 200 ° C. before use.

Regarding the regeneration air volume, the ratio between the regeneration air volume and the processing air volume may be determined so that the performance of the dehumidifying rotor is optimized. For example, it is possible to set the reproduction air volume: the processing air volume = 1: 2. This measure is possible because the regeneration air is taken from the exhaust of the power generation gas turbine in another system separate from the dehumidification supply and exhaust system. Such measures are difficult if air is used for returning air from the room to be air-conditioned and the regenerative air volume and the processing air volume are the same.

[0012] The outside air used for temperature reduction is as follows.
Even if it is not specially adopted, if a part of the outside air introduced for processing in the dehumidifying section of the dehumidifying rotor of the desiccant air conditioner is used, the system configuration can be simplified. In other words, the outside air taken in through a duct or the like to be introduced into the dehumidifying section of the dehumidifying rotor is branched by a branch duct, etc., and connected to and joined to the duct that constitutes the exhaust gas introduction path from the gas turbine to the regeneration section. I'm done.

When regeneration is performed by supplying high-temperature exhaust gas to the regeneration section of the dehumidification rotor as described above, the temperature of the air after passing through the dehumidification section and being subjected to the dehumidification process also becomes high. Therefore, it is difficult to use it for cooling even if the evaporative cooling process is performed as it is. Therefore, a water-air heat exchanger is further added, and heat exchange is performed between the air passing through the dehumidifying portion of the dehumidifying rotor and water by the water-air heat exchanger. If the temperature is lowered by performing the process, the air after the heat exchange can be humidified, that is, evaporated and cooled, and used for air conditioning such as cooling. In this case, when used for air conditioning without humidification, it is possible to supply air supply suitable for a factory or the like that requires a low humidity atmosphere.

On the other hand, the water whose temperature has been raised by the heat exchange in the water-air heat exchanger is used for hot water supply as described in claim 6, so that energy can be effectively used as a whole system. A reduction in overall efficiency can be prevented.

In the case where the temperature of the air passing through the dehumidifying portion of the dehumidifying rotor and the water is reduced by performing the heat exchange with the water by the water-air heat exchanger, the water-water heat exchanger is further provided. An exchange and a cooling tower, wherein the water used in the water-air heat exchanger uses cooling water cooled by the cooling tower,
The cooling water heated by the heat exchange in the water-air heat exchanger and heated is sent to the water-water heat exchanger to exchange heat with raw water for hot water supply. The cooling water after the heat exchange in the above may be returned to the cooling tower for cooling, and the raw water after the heat exchange in the water-water heat exchanger may be used for hot water supply. By using the cooling water from the cooling tower in this way, a system more suitable for the cooling load can be constructed.

In the case where the cooling water from the cooling tower is used, the cooling tower is provided with another water-air heat exchanger disposed downstream of the water-air heat exchanger. ,
The water passed through the other water-air heat exchanger is cooling water after being cooled by the cooling tower, and the air heat-exchanged by the water-air heat exchanger is immediately used for air conditioning. Instead, the heat exchange with the cooling water is performed by the other water-air heat exchanger disposed further downstream, and the air after the heat exchange by the other water-air heat exchanger downstream is May be used for air conditioning, and the cooling water after the heat exchange in the other water-air heat exchanger on the subsequent stage may be returned to the cooling tower for cooling. In this way, using a water-heat exchanger in two stages, the air that has been cooled down by heat exchange in the first stage is further heat-exchanged with the cooling water from the cooling tower in the second stage water-heat exchanger to be cooled. Therefore, there is an advantage that the number of coil rows can be reduced, and the system itself can be easily constructed.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a desiccant air conditioning system according to a preferred embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a system of a desiccant air-conditioning system according to a first embodiment. A gas turbine for power generation 1 has a compressor 3 for driving a generator 2, a combustion chamber 4, and a turbine 5. The air introduced through the filter 6 is compressed and introduced into the combustion chamber 4 so that the fuel gas G is supplied to the combustion chamber 4.
And burns it, thereby driving the generator 2 to generate power. The combustion gas is exhaust E
As X, the gas is discharged out of the power generating gas turbine 1 by the turbine 5. The generated electric power is transmitted to a power distribution unit 7 having corresponding electric facilities such as a substation of a machine room MR in a building B having a room R, power distribution facilities and storage batteries.

The desiccant air conditioner 11 is a rotatably driven dehumidifying rotor 1 containing, for example, zeolite as a desiccant.
2 is provided. The dehumidification rotor 12 has at least a dehumidification section 12a which is a dehumidification area and a regeneration section 12 which is a regeneration area.
b, and a purge area if necessary. For example, a known structure disclosed in JP-A-11-523 can be used. Dehumidifying part 1 of dehumidifying rotor 12
A part of the outside air OA taken in by the blower 14 through the filter 13 is introduced into 2a through a duct or the like. The rest of the outside air OA is
The mixture is mixed with the high-temperature exhaust EX from the power generation gas turbine 1 and introduced into the regeneration section 12b of the dehumidification rotor 12 via a duct or the like. The air that has passed through the regeneration unit 12b is discharged to the outside by the blower 15 through a duct or the like as exhaust EA.

The dehumidified air passing through the dehumidifying section 12a of the dehumidifying rotor 12 is cooled by a cooling coil 16 as a water-air heat exchanger, and then subjected to an evaporative cooling process in an evaporative cooler 17. Thereafter, the air is supplied to the chamber R as the air supply SA. As the evaporative cooler 17, not only a type in which mist or the like is sprinkled in a predetermined space to humidify, but also a type in which water is dropped into a filler installed in the predetermined space and humidified can be used.

Cooling water cooled to, for example, about 32 ° C. by the cooling tower 21 is supplied to the cooling coil 16 by a pump 22.
After passing through the dehumidifying section 12 a of the dehumidifying rotor 12, the heat is exchanged with the dehumidified air, the temperature is increased to, for example, 85 ° C., and then sent to the water-water heat exchanger 23. Then, in the water-water heat exchanger 23, raw water for hot water supply,
For example, after heat exchange with 40 ° C. water stored in the hot water tank (in the case of a water heater, water at about 40 ° C. located at the bottom), the heat is returned to the cooling tower 21 again to perform the cooling process. Attached to When tap water is used as raw water for hot water supply, it is preferable that the tap water is heated to about 40 ° C. in advance. Further, by using the cooling water from the cooling tower 21, the present system can be suitably applied to a cooling load.

On the other hand, in the water-water heat exchanger 23, the heat exchanged with the above-mentioned heated cooling water is heated to, for example, 75.degree.
Is sent to, for example, a water heater 25 as hot water supply equipment installed in the machine room MR.

The desiccant air-conditioning system according to the first embodiment has the above configuration. For example, the conditions of the outside air OA are now set to a temperature of 32 ° C. and an absolute humidity of 20.6 g / k.
An operation example in the case of g (DA) will be described. First, a high temperature exhaust gas EX generated in the power generation gas turbine 1 for power generation operation, for example, 280 ° C., is one of the outside air OA introduced for dehumidification. 20 parts mixed with
After the temperature is reduced to 0 ° C., the regeneration unit 12 of the dehumidification rotor 12
b to be used for regeneration of the desiccant. Since the desiccant is regenerated by air at 200 ° C., which is much higher than conventional hot water, the dehumidifying rotor 12
The dehumidifying ability of the is much improved than before. The air used for the regeneration and cooled down to, for example, about 65 ° C. is exhausted to the outside by the blower 15 as exhaust EA.

On the other hand, the other part of the outside air OA is dehumidified in the dehumidifying section 12a of the dehumidifying rotor 12, but is regenerated by the air at about 200 ° C. as described above.
Although the temperature of the dehumidified air is 90 ° C. or higher, the temperature is reduced to, for example, 37 ° C. by exchanging heat with the cooling coil 16. The absolute humidity is about 3 g / kg (DA). Then, after being dehumidified and cooled down to that extent, it passes through the evaporative cooler 17 and is subjected to evaporative cooling processing, and is supplied to the chamber R as air supply SA. The state of air in the above operation example is shown on the psychrometric chart of FIG. Reference numerals (a) to (e) in FIG. 2 respectively indicate air at points indicated by the same reference numerals on the system system in FIG.

On the other hand, the cooling water which has been heated by the heat exchange in the cooling coil 16 is heat-exchanged with the raw water for hot water supply in the water-water heat exchanger 23, cooled down, and returned to the cooling tower 21 again. And subjected to a cooling process. The raw water for hot water exchanged in the water-water heat exchanger 23 is sent to the water supply / drainage facility 25 as described above, and is used for hot water supply to the building B.

Therefore, in the desiccant air-conditioning system according to the above-described embodiment, since the high-temperature exhaust heat is used and the amount of dehumidification can be increased, the temperature of the dehumidified air is high. Heat from the cooling coil 16,
By recovering with the water-water heat exchanger 23, it can be used as hot water for hot water supply and the like, and the overall efficiency as cogeneration is secured.

According to the knowledge of the inventors, the COP (coefficient of performance) in the system is estimated to be about 0.5, which is a slightly lower value as the COP for cooling. However, since the temperature of the treated air is 90 ° C. or higher, the cooling water becomes hot water of 85 ° C. or higher, and heat is recovered from the hot water through the water-water heat exchanger 23, so that the water used for hot water supply is used. Thus, for example, water at 40 ° C. can be heated to about 75 ° C. The amount of heat that can be used for hot water supply is exhaust EX
It is about half the amount of heat that came out. That is, power is generated by the power generation gas turbine 1, and the power generation efficiency at that time is about 25%. At that time, the high temperature exhaust EX
About 50% of the input (fuel gas calorie) comes out. On the other hand, since the outside air OA after the dehumidification has a high temperature as described above, it is cooled by the cooling water from the cooling tower 21 and is cooled by the cooling amount. On the other hand, part of the cooling water is used for hot water supply load.

Therefore, each of the cooling air and the hot water
The heat recovery is about 50% of the heat quantity of X. That is, the cooling load is 25% of the input, and the hot water supply load is 25%.
% Efficiency. As a whole, the power is 25%, the cooling is 25%, and the hot water is 25% of the input. As for cooling, as mentioned above, the outside air is 3 g / kg.
(DA) can be dehumidified to about, and when it comes to hot water supply, 40
C. water can be raised to about 75.degree.

As described above, in the present embodiment, the exhaust E
Since hot water is made and used for hot water supply by recovering heat from the dehumidified air instead of from the X, the overall efficiency is almost the same as before, and the outside air can be dehumidified to a considerably lower level. . Such a level of dehumidification is an impossible value for a conventional desiccant air conditioner.

Next, a second embodiment will be described with reference to FIG. In the second embodiment, the configuration of the desiccant air conditioner 11 in the first embodiment is changed. Note that the same devices and the like in the desiccant air-conditioning system according to the first embodiment are denoted by the same reference numerals, and detailed description is omitted.

In the desiccant air conditioner 31 employed in the desiccant air conditioning system according to the second embodiment, the air that has been dehumidified by the dehumidifying section 12a of the dehumidifying rotor 12 is supplied with the first water-heat. Hot water coil 3 as exchanger
2, after heat exchange with raw water for hot water supply (for example, 40 ° C.), a cooling coil 3 as a second water-heat exchanger
In 3, the heat is exchanged with the cooling water sent from the cooling tower 21 by the pump 34, and then supplied to the chamber R as air supply SA.

That is, in the hot water coil 32, 40
℃, heat exchange with raw water, dehumidified air cooled,
After that, the temperature is further decreased by the cooling coil 33, and then supplied to the chamber R as the air supply SA as it is.

On the other hand, the raw water heated and exchanged with the dehumidified air in the hot water coil 32 to increase the temperature is sent by the pump 35 to the water heater 25 installed in the machine room MR of the building B. The cooling water that has been heated by the heat exchange with the high-temperature air in the cooling coil 33 is returned to the cooling tower 21 and subjected to a cooling process.

The main part of the desiccant air-conditioning system according to the second embodiment is configured as described above.
As in the first embodiment, the high-temperature exhaust gas of the power generation gas turbine 1 is directly used to improve the regeneration capability of the dehumidification rotor 12, and the low-humidity air supply SA is stored in the chamber R.
Can be supplied to Further, since the exhaust heat from the high-temperature air is recovered by the hot water coil 32 and used for hot water supply, the overall efficiency as cogeneration is secured.

Further, in the second embodiment, the first
In this embodiment, the water is supplied to the chamber R as it is without evaporative cooling. Therefore, the room R can supply conditioned air with extremely low humidity, and is suitable for air conditioning of the room R requiring a low humidity atmosphere, such as a filter manufacturing or a food factory. When air supply SA is supplied to an area where a person is active, the air supply SA may be supplied to the room R after humidification and cooling processing, as in the first embodiment.

Further, in the desiccant air-conditioning system according to the second embodiment, since the hot water coil 32 and the cooling coil 33 are used in two stages, the number of coil rows can be reduced.

[0036]

According to the present invention, when compared with a conventional system in which a gas turbine for power generation and a desiccant air conditioner are combined, the dehumidifying ability of the desiccant air conditioner is dramatically improved, and air of lower humidity is provided. Can be obtained. Even when the temperature of the exhaust gas from the gas turbine is too high, the temperature can be lowered to an appropriate regeneration temperature by mixing with the outside air, so that various types of gas turbines for power generation can be used. In addition, by using a part of the outside air introduced for processing the outside air used for cooling in the dehumidifying section of the dehumidifying rotor of the desiccant air conditioner, the duct piping and the entire system are simplified.

By exchanging heat between the air and water passing through the dehumidifying section of the dehumidifying rotor by the water-air heat exchanger, it is possible to appropriately cope with a subsequent air conditioning load. In addition, by using the water heated by the heat exchange in the water-air heat exchanger for hot water supply, energy can be used effectively as a whole system and a system with almost the same overall efficiency as the conventional system can be constructed. It is possible to

[Brief description of the drawings]

FIG. 1 is an explanatory diagram schematically showing a configuration of a desiccant air-conditioning system according to a first embodiment of the present invention.

FIG. 2 is an air line diagram showing a change in air state in an operation example of the desiccant air conditioning system according to the embodiment of the present invention.

FIG. 3 is an explanatory diagram schematically showing a configuration of a desiccant air conditioning system according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power generation gas turbine 11 Desiccant air conditioner 12 Dehumidification rotor 12a Dehumidification part 12b Regeneration part 16 Cooling coil 17 Evaporative cooler 21 Cooling tower 23 Water-water heat exchanger B Building R Room OA Outside air SA Supply EA Exhaust EX Exhaust

Continued on the front page F term (reference) 3L053 BC03 BC09 3L055 AA10 BA00

Claims (8)

[Claims] 1. A desiccant air conditioner having a power generating gas turbine and a dehumidifying rotor having a desiccant, and introducing exhaust gas of the power generating gas turbine into a regeneration unit of the dehumidifying rotor of the desiccant air conditioner. A desiccant air-conditioning system, characterized in that: 2. The method according to claim 1, wherein the exhaust gas from the power generation gas turbine is introduced into the regeneration section of the dehumidifying rotor of the desiccant air conditioner by being mixed with outside air. Desiccant air conditioning system. 3. The outside air mixed with the outside air and introduced is a part of the outside air introduced for processing in the dehumidifying section of the dehumidifying rotor of the desiccant air conditioner. Item 3. Desiccant air conditioning system according to item 2. 4. A heat-exchanger further comprising a water-air heat exchanger, wherein the water-air heat exchanger exchanges heat between air passing through the dehumidifying section of the dehumidifying rotor and water. 4. The desiccant air conditioning system according to claim 1, wherein the air after humidification is used for air conditioning. 5. A water-air heat exchanger, wherein the water-air heat exchanger performs heat exchange between air passing through the dehumidifying section of the dehumidifying rotor and water, and the heat exchange The desiccant air-conditioning system according to any one of claims 1, 2, and 3, wherein the subsequent air is used for air-conditioning without humidification. 6. The desiccant air conditioning system according to claim 4, wherein the water heated by the heat exchange in the water-air heat exchanger is used for hot water supply. 7. A water-water heat exchanger and a cooling tower, wherein the water passed through the water-air heat exchanger is cooling water cooled by the cooling tower. The cooling water after the heat exchange in the heat exchanger is sent to the water-water heat exchanger to exchange heat with the raw water for hot water supply, and
The cooling water after the heat exchange in the water heat exchanger is returned to the cooling tower for cooling, and the raw water after the heat exchange in the water-water heat exchanger is used for hot water supply. The desiccant air conditioning system according to claim 4 or 5, wherein 8. The water-to-air heat exchanger further comprising another water-to-air heat exchanger and a cooling tower disposed downstream of the water-to-air heat exchanger. Is cooling water cooled by the cooling tower, and the air heat exchanged by the water-air heat exchanger is not immediately used for air conditioning, and is further cooled by the other water-air heat exchanger. After the heat exchange with water, the air after heat exchange in the other water-air heat exchanger is used for air conditioning, and the cooling water after heat exchange in the other water-air heat exchanger is 7. The desiccant air-conditioning system according to claim 6, wherein cooling is performed by returning to a cooling tower.