JP2001214754A - Humidification tower for high moisture gas turbine system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a humidification tower which has a small volume and a lighter weight, can provide a lower temperature liquid phase water, and is excellent in economical efficiency and operability. SOLUTION: This humidification tower for gas turbine system is formed so that combustion air 6 is supplied from the vicinity of the lower part, liquid phase water 21 and 22 heated by the exhaust gas of a gas turbine is supplied from the upper part, and the combustion air is humidified by the contact of the ascending combustion air with the falling liquid phase water. A water catching device 28 for receiving the falling liquid phase water and guiding it to the outside of the humidification tower is provided in the vertical middle part within the humidification tower, so that the distribution of the liquid phase water quantity falling in the humidification tower is larger in the upper part side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a humidification tower for a high-humidity gas turbine system, and more particularly to a method for bringing combustion air into contact with liquid-phase water heated by gas turbine exhaust gas to reduce moisture in the combustion air. A humidification tower of a high humidity gas turbine system configured to provide.

[0002]

2. Description of the Related Art Heated liquid-phase water and air are brought into contact inside a humidification tower to obtain a mixture of air and steam and cooled liquid-phase water. For a so-called high-humidity gas turbine system that uses liquid phase water for recovery and compressor intermediate cooling, for example,
No. 31012, or "HAT (High Humidity Gas Turbine) Cycle" (Thermal Nuclear Power Generation Vol. 43, No. 12).

Further, as a type of a humidification tower used in this high humidity gas turbine system, for example, "Advanced T
urbine Systems: System Scoping and Feasibility Stud
As disclosed in the study example of "y" (DOE / MC / 29247-3375), a method using a packed tower and a method using a spray tower are considered.

[0004] Other than these, those related to the humidification tower of a high-humidity gas turbine include, for example, Japanese Patent Publication No. Sho 63-3
No. 2970 or Japanese Patent Publication No. 1-31013.

[0005]

In order for the humidifying tower to make sufficient contact between air and high-temperature water and to transfer necessary heat and steam, a sufficient contact distance must be provided. For example, as an example, assuming a high-humidity gas turbine system having a power of 25 MW, the length of a packed bed in which air and high-temperature water are contacted needs to be calculated to be about 5 m, and actual humidification is required. The tower is expected to take longer.

[0006] In addition, the humidifying tower has a strong pressure vessel because the pressure in the humidifying tower is almost equal to the discharge pressure of the gas turbine compressor, and the physique is slightly increased in size. But it is expensive. In addition, if the internal volume of the humidification tower is large, the volume of the air flow path from the compressor to the combustor becomes large, and the responsiveness may be deteriorated. For this reason, minimizing the size of the humidifying tower as much as possible is an important requirement from both the manufacturing cost and operability of this type of system.

The present invention has been made in view of the foregoing, and it is an object of the present invention to provide a small-sized, that is, small-volume, light-weight, lower-temperature liquid-phase water and excellent economical efficiency and operability. It is to provide a humidification tower of this kind.

[0008]

That is, the present invention provides an improved gas turbine system which is configured to contact liquid air heated by gas turbine exhaust gas with combustion air to provide moisture to the combustion air. In the wet tower, the liquid water volume distribution in the humidification tower is formed so that the higher liquid water temperature is higher than the lower liquid water temperature to achieve the intended purpose. .

Further, according to the present invention, while air for combustion is supplied from the vicinity of the lower part, liquid-phase water heated by gas turbine exhaust gas is supplied from the upper part, the ascending combustion air and the liquid phase falling In a humidification tower of a gas turbine system configured so that moisture is given to the combustion air by contact with water, the falling liquid-phase water is received at a vertically intermediate portion inside the humidification tower. At the same time, a water catcher is provided outside the humidifying tower, and the distribution of the amount of liquid phase water falling inside the humidifying tower is formed so that the upper part of the water phase increases.

In this case, the liquid-phase water is supplied at a plurality of locations in the flow direction of the air. Further, a water temperature adjusting means for adjusting the temperature of the liquid phase water supplied to the humidification tower is provided in the supply path of the liquid phase water. Further, the supply of the air is formed at a plurality of positions in the flow direction of the liquid phase water. Further, an air temperature adjusting means for adjusting the temperature of the air supplied to the humidification tower is provided in the air supply path.

That is, in the humidification tower of the high-humidity gas turbine system formed as described above, the distribution of the liquid-phase water in the humidification tower is such that the higher the liquid-phase water temperature is, the higher is the liquid-phase water temperature. Since the liquid phase water is evaporatively active near the top of the humidifying tower with high temperature, efficient humidification is performed, the volume is reduced, and Liquid water can be obtained.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments. FIG. 1 shows a system of a high-humidity gas turbine system provided with the humidification tower. The humidification tower is indicated by reference numeral 5 in the center of the figure,
2 is a compressor, 10 is a turbine, 9 is a combustor, 15 is a water recovery unit, and 18 is a chimney.

In this gas turbine system, the air 3 is compressed by the compressor 2 and then enters the humidification tower 5 via the post-cooler 4. Water is sprayed at the compressor inlet, and in the humidification tower 5, the air 6 comes into contact with the high-temperature liquid-phase water 21, 22 to be heated and humidified to become high-humidity air 7. The high-humidity air 7 is heated by the regenerator 8 and reacts with fuel in the combustor 9 to become a high-temperature gas to drive the turbine 10.

The exhaust gas 11 of the turbine 10 is generally 500
The regenerator 8 and feed water heater 1
At 2, heat recovery is performed. The exhaust gas 13 after the heat recovery by the feed water heater 12 is guided to the water recovery unit 15 and the cooling water 16
And the moisture contained in the exhaust gas is condensed and collected. A part of the recovered water 14 is used as cooling water of the post-cooler 4 and spray water to the gas turbine compressor inlet via the water treatment device 25. Further, a part of the recovered water 14 is guided to a cooling water cooler 27, adjusted to a desired temperature, and then reused as the cooling water 16.

The exhaust gas that has passed through the water recovery unit 15 is guided to an exhaust gas reheater 17 and exchanges heat with the exhaust gas 19 before passing through the water recovery unit, and the exhaust gas is heated to a temperature sufficiently higher than the dew point, for example, 9 ° C.
It is heated to about 0 ° C. and discharged from the chimney 18 into the atmosphere.

Next, a detailed configuration of the humidification tower 5 and an operation method thereof will be described. High-temperature liquid-phase water 21 and 22 are supplied to the upper part of the humidification tower 5 to form a water film on the internal packing. On the other hand, low-temperature air 6 cooled by the post-cooler 4 is supplied from near the lower part. The liquid-phase waters 21 and 22 fall downward due to gravity, come into contact with the air 6 to transmit sensible heat and water vapor, are deprived of sensible heat and latent heat of vaporization of water vapor, and are cooled. Therefore, the temperature of the liquid-phase waters 21 and 22 decreases as it goes below the humidification tower, and the temperature and humidity of the air 6 rises as it goes above the humidification tower.

Since the liquid water 23 that has passed through the packed bed of the humidification tower is used as a refrigerant for recovery of exhaust heat, the lower the temperature, the greater the amount of exhaust heat recovery. Therefore, in order to reduce the size of the humidification tower without lowering the thermal efficiency of the entire system, the amount of sensible heat and latent heat of water vapor transferred from liquid water to air, that is, the amount of heat transfer per unit volume of the humidification tower, must be increased. The liquid water must be lowered to a predetermined temperature. Since the latent heat of steam accounts for about 90% of the total heat transfer transferred from the liquid water to the air inside the humidification tower, it is important to increase the transfer of steam.

In the humidification tower, the amount of water vapor transmission m per unit volume from liquid water to air is expressed by the following equation.

[0019]

[Number 1] _{m = h D · A · (} Y i -Y) ... (1) where, h _D is material transfer coefficient, A is the contact area of the liquid-phase water and air per unit volume, Y _i is the gas At the liquid interface humidity, equal to the air saturation humidity at the liquidus water temperature, Y is the air humidity. A increases in proportion to the liquid phase water, Y _i is increased in proportion to the liquid phase water temperature. Therefore, the gas-liquid contact area increases when the amount of liquid phase water is large, and the humidity difference (Y
_i− Y) increases, and the amount of water vapor transmitted per unit volume increases.

FIG. 2 (a) shows a calculation of the temperature distribution of liquid water and air inside a normal countercurrent humidification tower. The temperature of the liquid water drops rapidly as it goes to the bottom of the tower. . FIG. 2 (b)
, The saturation humidity of air rises exponentially with temperature. Therefore, the higher the temperature of the liquid phase water, the greater the difference in humidity (Y _i -Y), and therefore, in the countercurrent humidification tower, the vaporization of the liquid phase water is most active near the top of the tower. FIG. 1 shows a first embodiment of the present invention in which a large amount of liquid-phase water is distributed on the top side of a tower having a high liquid-phase water temperature by utilizing this property.

The falling liquid-phase water is received inside the humidifying tower,
And a gutter leading out of the humidification tower, ie, a liquid phase water catcher 2
8 is installed to collect a part of the liquid water that has fallen.
The collected liquid phase water is sent into the heat exchanger tubes of the post-cooler 4 and the feed water heater 12, and is used again as a heat recovery refrigerant. The remaining liquid-phase water not collected by the water trap 28 passes through a packed bed at the lower part of the humidification tower, and is further used as a lower-temperature heat recovery refrigerant after the temperature is further lowered. The present invention thus creates a state in which the amount of liquid water is large at the top of the humidification tower, and increases the amount of heat exchange per unit volume.

FIG. 3 shows a second embodiment of the present invention. This embodiment is different from the above-described embodiment in that a water trap 33 is provided in the humidification tower.
Is added to increase the number of liquid-phase water recovery stages, so that the distribution of the liquid-phase water amount can be adjusted more finely, and the humidification tower can be further miniaturized. It is possible to further increase the number of installed water catchers.

FIG. 4 shows a third embodiment of the present invention. In this embodiment, a plurality of liquid-phase water supply points are provided in the humidifying tower so that the temperature of the liquid-phase water inside can be adjusted. Liquid phase water 21, 2 that has passed through post-cooler 4 and feedwater heater 12
2 is divided into 34, 35 for feeding to the upper half of the tower and 36, 37 for feeding to the lower half of the tower. The liquid-phase waters 34 and 35 are brought into contact with the air 6 supplied from the bottom of the tower at the upper half of the tower, and then cooled. Used as a heat recovery medium in the feed water heater 12.

The liquid-phase waters 36 and 37 come into contact with the air 6 supplied from the bottom of the tower in the lower half of the tower and cool the same.
Used as heat recovery medium via 4 and 26. In this embodiment, since the high-temperature liquid-phase waters 21 and 22 are supplied to two locations, the maximum temperature of the liquid-phase water appears at two locations in the humidification tower. The higher the temperature of the liquid phase water, the greater the difference in humidity is generated, and the more the evaporation becomes active, the greater the heat exchange amount per unit volume of the humidification tower. In addition, high-temperature liquid-phase water 21 and 22
Is divided into two parts, so that the flow ratio of the air 6 serving as the cooling side fluid at the lower part of the tower becomes larger than the flow rate of the liquid phase water serving as the heating side fluid. It is advantageous to obtain.

FIG. 5 shows a fourth embodiment of the present invention in which the size of the humidification tower is reduced based on the same principle as the embodiment of FIG. This embodiment will be described focusing on the differences from the embodiment of FIG. In the embodiment of FIG. 5, after the temperature of the high-temperature liquid-phase waters 31 and 32 supplied to the upper half of the tower decreases in the humidification tower, the water is collected by the water catcher 28, and the post-cooler 4 and the water supply It is characterized in that after supplying to the heater 12 and reheating, it is supplied to the lower half of the humidification tower.

That is, unlike the embodiment of FIG. 4, the temperature of the liquid-phase water 36, 37 supplied to the lower half of the humidification tower is adjusted by the amount of heating in the post-cooler 4 and the feed water heater 12, and The temperature can be set differently from the temperature of the liquid-phase waters 21 and 22 supplied to the halves. Therefore, it is advantageous when it is desired to quickly adjust the temperature of the liquid phase water 23 obtained from the humidification tower.

FIG. 6 shows a fifth embodiment of the present invention. In this embodiment, the liquid-phase water supplied to the humidification tower is heated to a high temperature of 21,2.
It is characterized in that it is supplied separately into 2 and 39 and 40 at low temperature. Although the high-temperature liquid-phase water is easily evaporated as described in the embodiment of FIG. 1, when the temperature of the liquid-phase water supplied to the humidification tower increases, the liquid-phase water which can be taken out even if the evaporation amount in the tower is the same. There is a disadvantage that the temperature becomes high. The purpose of this embodiment is to improve this point. At the top side of the humidification tower, the temperature of the air is raised and humidified by high-temperature liquid-phase waters 21 and 22 close to the boiling point.
The water is collected by the water catcher 28 and used for heat recovery on the high temperature side. On the bottom side, liquid-phase water 39, 40 close to the temperature of the inflow air 6 is supplied to produce low-temperature liquid-phase water 23, which is used for heat recovery on the low-temperature side.

Since the liquid-phase water temperature is high at the top of the tower, the gas-liquid interface humidity Yi in the equation (1) is large, and a large difference in humidity is generated, so that evaporation is activated. On the other hand, at the bottom of the tower, Yi is small because the water temperature is low, but a large humidity difference still occurs because the humidity Y is small immediately after the air in contact with the liquid phase water flows into the humidification tower. Therefore, evaporation is actively performed on both the tower top side and the tower bottom side, and the amount of heat exchange per unit volume of the humidification tower is increased, so that the humidification tower can be downsized.

FIG. 7 shows a sixth embodiment of the present invention. In this embodiment, the internal air temperature distribution can be controlled for a co-current humidification tower. When the packed tower cannot be used as a humidifying tower because the pressure loss is severely restricted, it is conceivable to adopt a spray tower type in which gas-liquid is contacted by water spray regardless of the packed body. In order to prevent the spray droplets from scattering, it is advantageous to employ a co-current system in which the spray direction of the liquid phase water and the flow direction of the air are the same.

When air and liquid phase water are simply brought into co-current contact,
The high-temperature liquid-phase water comes into contact with the low-temperature air that has passed through the post-cooler, so that the liquid-phase water does not easily evaporate, and a long humidification tower is required. Since air cannot contain water vapor at or above the saturation humidity, the amount of liquid water that can be evaporated is limited by the saturation humidity of the air that is in contact, but as shown in FIG. It decreases rapidly when it gets lower. Therefore, after the air is heated by the sensible heat of the liquid phase water and the air saturation humidity increases, the liquid phase water corresponding to the increased saturation humidity evaporates. It is because it is limited by.

The embodiment of FIG. 7 relieves this condition.
A plurality of air supply points are provided in the humidification tower, and air at different temperatures is supplied to each of them. At the top of the tower, high-temperature liquid-phase water 21 and 22
Then, the high-temperature air 42 is supplied to activate the evaporation of the liquid-phase water. At this time, if air having a temperature higher than the liquid-phase water temperature is supplied, heat is also taken from the air during liquid-phase water evaporation, and the air temperature decreases. Low-temperature liquid-phase water 39 and 40 and low-temperature air 6 are supplied to the lower part of the tower. In the co-current humidification tower, the air temperature rises at the same time as the cooling of the liquid phase water proceeds by evaporation,
The drawback is that the temperature of the liquid phase water that can be removed is high, but with this method, the liquid phase water comes into contact with the hot air first, and then with the cold, low-humidity air. Water is obtained.

Next, in order to show the effectiveness of the present invention, an example is shown in which the required filling height is calculated for a humidifying tower of the packed tower system. Table 1 shows the calculation conditions, and Table 2 shows the calculation results.

[0033]

[Table 1]

[0034]

[Table 2]

As described above, according to the humidification tower of the humidified gas turbine system formed as described above, the trapping for receiving the falling liquid-phase water is provided at a vertically intermediate portion inside the humidification tower. A vessel is provided and the distribution of liquid-phase water falling in the humidification tower is formed so as to increase on the upper side, so evaporation of liquid-phase water is most active near the top of the high-temperature humidification tower. Thus, efficient humidification is performed. Therefore, the volume is small and lightweight, sufficient humidification is performed, and low-temperature liquid-phase water can be obtained.

[0036]

As described above, according to the present invention, a small-sized, that is, small-volume, light-weight, liquid-phase water at a lower temperature can be obtained, and this kind of increase in economic efficiency and operability can be obtained. Wet tower can be obtained.

[Brief description of the drawings]

FIG. 1 is a system diagram of a high-humidity gas turbine system provided with a humidification tower of the present invention.

FIG. 2 is a temperature distribution diagram inside a conventional humidification tower and a relationship diagram between air temperature and saturation humidity.

FIG. 3 is a system diagram showing another embodiment of the humidification tower of the present invention.

FIG. 4 is a system diagram showing another embodiment of the humidification tower of the present invention.

FIG. 5 is a system diagram showing another embodiment of the humidification tower of the present invention.

FIG. 6 is a system diagram showing another embodiment of the humidification tower of the present invention.

FIG. 7 is a system diagram showing another embodiment of the humidification tower of the present invention.

[Explanation of symbols]

1 ... load, 2 ... compressor, 3 ... air, 4 ... post-cooler, 5
... humidifying tower, 6 ... air, 7 ... high humidity air, 8 ... regenerator, 9
... combustor, 10 ... turbine, 11 ... exhaust gas, 12 ... feed water heater, 13 ... exhaust gas, 14 ... recovered water, 15 ... water recovery device, 16 ... cooling water, 17 ... gas reheater, 18 ... chimney,
19 ... exhaust gas, 20 ... exhaust gas, 21 ... liquid phase water, 22 ... liquid phase water, 23 ... liquid phase water, 24 ... pump, 25 ... intake spray water, 26 ... pump, 27 ... cooling water cooler, 28 ... trapping Water bottle, 29 ... pump, 30 ... pump, 31 ... pump, 32
... Pump, 33 ... Catcher, 34,35,36,37 ... Liquid phase water, 38 ... Intercooler, 39,40 ... Liquid phase water, 41 ...
Makeup water.

Claims (8)

[Claims] 1. A humidification tower of a gas turbine system configured to contact liquid-phase water heated by gas turbine exhaust gas with combustion air to give moisture to combustion air. A humidification tower for a high-humidity gas turbine system, wherein the liquid-phase water amount distribution is formed such that the side having a higher liquid-phase water temperature is higher than the side having a lower liquid-phase water temperature. 2. A humidification tower of a gas turbine system which is configured to bring liquid phase water heated by gas turbine exhaust gas into contact with combustion air to give moisture to combustion air. A humidification tower for a high-humidity gas turbine system, characterized in that the liquid-phase water amount distribution is adjusted so that a side with a higher liquid-phase water temperature is higher than a side with a lower liquid-phase water temperature. 3. A combustion air is supplied from near a lower portion, and a liquid-phase water heated by gas turbine exhaust gas is supplied from an upper portion. In the humidification tower of the gas turbine system, which is formed so that moisture is given to the combustion air by the contact, the falling liquid-phase water is received at a vertically intermediate portion inside the humidification tower, A humidification tower for a high-humidity gas turbine system, wherein a water catcher is provided outside the humidification tower, and a distribution of liquid-phase water falling in the humidification tower is formed so as to increase on an upper side. 4. The humidification tower of a high-humidity gas turbine system according to claim 3, wherein the water catchers are provided in a plurality of stages in a flow direction of the liquid phase water. 5. The humidification tower of a high-humidity gas turbine system according to claim 3, wherein the supply of the liquid-phase water is performed at a plurality of locations in the flow direction of the air. 6. The high-humidity gas according to claim 3, wherein a water temperature adjusting means for adjusting the temperature of the liquid-phase water supplied to the humidification tower is provided in the liquid-phase water supply path. Humidification tower for turbine system. 7. The humidification of a high-humidity gas turbine system according to claim 3, wherein the supply of the air is performed at a plurality of locations in a flow direction of the liquid-phase water. Tower. 8. The high-humidity gas turbine system according to claim 3, wherein an air temperature adjusting means for adjusting the temperature of the air supplied to the humidification tower is provided in the air supply path. Humidification tower.