JPH0842358A - Cooling tower white smoke preventing device - Google Patents

Abstract

PURPOSE:To prevent generation of white smoke to be generated by exhaust air from a wet-type cooling tower by making use of exhaust gas of a gas turbine. CONSTITUTION:A smokestack 3 connected to an exhaust gas boiler 2 making use of exhaust gas of a gas turbine is connected to a cooling tower 5 by a duct 10, and a controlling damper 4 is provided in the position higher than the duct 10 in the smokestack 3, and a controlling damper 11 is provided in the duct 10. When the possibility of white smoke is generated after the atmospheric temperature is lowered, the controlling damper 4 in the smokestack 3 is closed, and the controlling damper 11 in the duct 10 is opened, thereby exhaust air 9 to be discharged from the upper part of the cooling tower 5 is heated by exhaust gas of the gas turbine 1, and white smoke is prevented from being generated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a cooling tower white for preventing white smoke generated from the wet cooling tower by heating the exhaust air temperature of the wet cooling tower with the exhaust gas of a gas turbine or the exhaust heat recovery boiler. The present invention relates to a smoke prevention device.

[0002]

2. Description of the Related Art When a conventional wet cooling tower is provided with a white smoke prevention function, a dry cooling section is provided inside the cooling tower to heat the exhaust air, but the heating temperature is low. It did not have a good white smoke prevention function. Further, since the dry cooling unit is provided, the structure becomes large and the price becomes expensive. FIG. 2 shows an example of a conventional wet cooling tower with a white smoke prevention function. In FIG. 2, the wet cooling tower 21 is mainly composed of the following members and parts. That is, the main body 21, the motor moving fan 22, the hot water supply pipe 23 sent from the condenser and the like, the sprinkler 25, the filling body 2
9. A collection pipe 26 for sending cold water to a condenser, etc.,
The filling body 29 is a device for more efficiently cooling water drops that naturally fall. The air 28 for cooling the hot water enters the cooling tower body 21 via the louver 27, cools the hot water with the packing 29, and is discharged to the atmosphere. The air released at this time is hotter and more humid than the atmosphere, so that the vapor is condensed into minute water droplets, which can be visually recognized as white smoke when exposed to light. To prevent this, hot water supply pipe 2
A fin-tube 24 is used as a part of No. 3, and a means for heating the discharged air to lower the humidity is used as a wet-dry combined cooling tower.

[0003]

The warm air discharged from the cooling tower is usually harmless, but white smoke happens to be visible and has been highlighted as an environmental problem. Therefore, in order to prevent white smoke from being generated in the vicinity of the cooling tower, it is sufficient to raise the temperature of the discharged air to make it difficult for water vapor to condense. It was not good. The present invention is intended to solve the above-mentioned conventional problems, and is intended to prevent white smoke in a cooling tower by heating exhaust air.

[0004]

For this reason, the present invention is directed to a gas turbine exhaust gas or a gas turbine exhaust gas in a plant having a gas turbine and a wet cooling tower device or a gas turbine combined cycle power generation facility and a wet cooling tower device. A part or all of the exhaust gas from the exhaust heat recovery boiler using gas is guided to the wet cooling tower to heat the exhaust air, thereby preventing white smoke from the cooling tower. A duct connects the chimney connected to the heat recovery boiler with a wet cooling tower, and a control damper at the inlet of the cooling tower is installed in the duct, and another control damper is installed in the chimney connected to the exhaust heat recovery boiler. Which is a means for solving the problems.

[0005]

The wet cooling tower and the exhaust heat recovery boiler are connected by a duct, and a control damper is provided in the duct. First, when the atmospheric temperature is high and there is no fear of white smoke, the control damper at the inlet of the cooling tower is closed and the damper in the chimney is fully opened. Next, when the atmospheric temperature drops and the possibility of white smoke comes out, if the damper in the stack is closed and the control damper at the inlet of the cooling tower is fully opened, the air discharged from the cooling tower is heated. The white smoke can be prevented. That is, in a power plant using a gas turbine, there is a large amount of clean exhaust gas. Therefore, white smoke can be prevented by introducing part or all of this exhaust gas to the cooling tower.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of the present invention. Now, the present invention is to prevent the white smoke by heating the air discharged from the cooling tower with the exhaust gas. In a power plant using a gas turbine, there is a large amount of clean exhaust gas, and white smoke can be prevented by introducing a part or all of this exhaust gas to a cooling tower. This principle will be described with reference to the moist air diagram of FIG. 3 before describing the embodiment of the present invention of FIG. In FIG. 3, a line S indicates a saturated air wet line, and in the zone on the left side of this line, water droplets condense to generate white smoke, and in the right zone, white smoke does not occur. In a typical cooling tower outlet, a state of point A, the atmospheric temperature when from T _C changes state to C from A (temperature exhaust gas is cooled). Since this state change is in the zone on the right side of the saturated air wet line S, white smoke is not generated. However, when the atmosphere falls from T _C to T _B , the state changes from A to B, so white smoke is generated at the outlet of the cooling tower. In order to avoid this, if the exhaust air at the point A is heated and moved to the point C'and the state is changed from C'to B, the zone on the right side of the saturation line S becomes white smoke. Does not occur.

Referring to FIG. 1, 1 is a gas turbine, 2 is an exhaust gas boiler, 3 is a chimney for discharging exhaust gas, and 4 is a control damper provided in the chimney 3.
Further, 5 is a cooling tower, and hot water 6 sent from a condenser or the like is cooled by outside air 8 and discharged as cold water 7, and exhausted air 9
Is discharged from the upper part of the cooling tower 5. A duct 10 connects the exhaust gas boiler 2 and the cooling tower 5, and a control damper 11 is provided in the duct.

The operation will be described next. When the atmospheric temperature is high and there is no fear of white smoke, the control damper 11 at the inlet of the cooling tower 5 is closed and the control damper 4 in the chimney 3 is fully opened. Drive in the condition. Next, when the atmospheric temperature drops and white smoke is likely to occur, the damper 4 above the connecting position of the duct 10 in the chimney 3 is closed, and the control damper 11 at the inlet of the control tower 5 is fully opened. If you leave it, duct 10
The exhaust gas further flows into the cooling tower 5 to heat the exhaust air 9 and the state described with reference to FIG. 3 is achieved, whereby white smoke can be prevented. There are also two dampers, a control damper 4 in the chimney and a cooling tower 5.
Depending on the capacity of the gas turbine 1, the capacity of the cooling tower, and the like, the control damper 11 at the inlet can increase / decrease the amount of exhaust air by performing a part of opening / closing control from the operation of fully opening and fully closing. Although the bypass duct 10 from the chimney 3 is connected to the outlet side of the fan 12 in the cooling tower 5 in FIG. 1, it may be connected to the inlet side.

[0009]

As described in detail above, according to the present invention, when the atmospheric temperature is high and there is no fear of white smoke, the control damper at the inlet of the cooling tower is closed and the control damper in the chimney is fully opened. Just drive. When the temperature of the atmosphere drops and white smoke is likely to occur, the control damper in the chimney can be closed and the control damper at the cooling tower inlet can be fully opened for operation, adding exhaust air from the cooling tower. The temperature can be raised, so that the generation of white smoke due to the exhaust air from the cooling tower can be prevented.

[Brief description of drawings]

FIG. 1 is a system diagram of a cooling tower white smoke prevention device according to an embodiment of the present invention.

FIG. 2 is a sectional view showing an example of a conventional wet cooling tower.

FIG. 3 is an explanatory diagram showing the principle of a moist air diagram.

[Explanation of symbols]

 1 Gas Turbine 2 Exhaust Gas Boiler 3 Chimney 4 Control Damper 5 Cooling Tower 6 Hot Water 7 Cold Water 8 Outside Air 9 Exhaust Air 10 Bypass Duct 11 Control Damper 12 Fan

Claims (2)

[Claims] 1. In a plant having both a gas turbine and a wet cooling tower device or a gas turbine combined cycle power plant and a wet cooling tower device, exhaust gas of a gas turbine or exhaust gas of an exhaust heat recovery boiler using exhaust gas of a gas turbine is discharged. A cooling tower white smoke prevention device, characterized in that white smoke in a cooling tower is prevented by guiding a part or all of gas to a wet cooling tower to heat exhaust air. 2. The cooling tower white smoke prevention device according to claim 1, wherein the chimney connected to the exhaust heat recovery boiler and the wet cooling tower are connected by a duct, and a damper for controlling the inlet of the cooling tower is provided in the duct. A cooling tower white smoke prevention device characterized in that another control damper is provided in a chimney connected to the exhaust heat recovery boiler.