JPH072704U - Emergency water supply - Google Patents

Abstract

(57) [Summary] [Purpose] When the boiler water supply pump is stopped, the boiler water supply is supplied from the water supply container that was stored in advance, and the time until restarting is shortened. [Constitution] A water supply container 7 connected to a boiler water supply pipe 6 is provided via an emergency water supply pipe 19. The water supply container 7 communicates with the air container 8 by a connecting pipe 20 having a water supply valve 12. Stop valve
A signal output from the control device 10 is applied to the 11, the sluice valve 16, and the bypass valve 18 to control opening / closing.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an emergency water supply system for continuously sending boiler water to a boiler of a thermal power plant even when the boiler water supply pump is stopped.

[0002]

[Prior art]

 The boiler feed water pump (hereinafter referred to as BFP) of a thermal power plant usually has a standby unit installed, but it takes several minutes to start after the main BFP driven by the turbine stops. Also, in the case of a motor-driven standby unit BFP, it cannot be started when the plant is completely stopped, and the boiler feed water cannot be supplied.

A water supply device of a thermal power plant is only BFP, and does not have a means for constantly sending other water supply to a boiler regardless of an emergency. Especially in a fluidized bed boiler, fuel is contained in layers inside the boiler, and if the main BFP is stopped in an emergency and the boiler water supply stops, even if fuel supply to the boiler is stopped. , The residual heat quantity of the fuel left in the boiler is very large, and there is a risk of damage to the overheated boiler tube. Therefore, a cooling method of injecting water into the fuel in the boiler (hereinafter referred to as cold blow-off) is usually used.

[0004]

[Problems to be solved by the device]

 However, when cold blow-off is performed, the fuel in the boiler becomes ash mixed with water in the boiler, and even if the BFP is immediately restarted, the fuel becomes ash mixed with water. The boiler cannot be started until it is removed. Therefore, even if the BFP is stopped for a very short time, it takes a wasteful time (about 24 hours) to remove the ash to restart the plant.

The present invention has been made in view of the above circumstances, and it is possible to shorten the time until restarting by supplying boiler feed water from the water supply container that was stored in advance when the BFP was stopped. It is intended to provide a water supply device.

[0006]

[Means for Solving the Problems]

 The emergency water supply device according to the present invention communicates with a water supply pipe and a water supply container communicating with the emergency water supply pipe, a water supply container and a communication pipe having a water supply valve, and a compressor and an air pipe. An air container and a stop valve provided upstream of the water supply pipe that communicates with the water supply container are provided.

[0007]

[Action]

 When the BFP stops, open the water supply valve between the air container and the water container, which is filled with high-pressure air by the compressor in advance. In this way, it is possible to instantly supply water to the boiler when the BFP is stopped.

[0008]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic view showing an example of the emergency water supply device of the present invention. That is, a thermal power plant consisting of the steam turbine 1, the generator 2, the condenser 3, the main BFP 4, and the boiler 5 is provided with the water supply container 7 connected to the boiler water supply pipe 6 via the emergency water supply pipe 19. The water supply container 7 is always in communication with the air container 8 by a communication pipe 20 having a water supply valve 12 so that the water is filled with the same pressure as the boiler water supply pipe 6. Further, the high pressure air from the compressor 9 can be introduced into the air container 8 through the air pipe 21 and filled therein. When the main BFP 4 is stopped, the stop valve 11 is closed by the control device 10, and then the water supply valve 12 is opened so that the water in the air container 8 filled to a higher pressure than the water supply container 7 is supplied with the water supply container. The water in 7 is continuously sent to the boiler 5. At that time, the stop valve 14 is opened to operate the main steam bypass system 13, and the main steam pressure of the boiler 5 is lowered. That is, the pressure in the air container 8 drops rapidly after the water supply valve 12 is opened, but it is still possible to continuously supply the water supply to the boiler 5.

After the main BFP 4 is stopped, the standby device BFP 15 is activated. The standby machine BFP15 may have its own power such as diesel drive in consideration of the total stoppage of the station. In addition, the motor-operated standby machine BFP may be driven if an appropriate power source is obtained even when the main BFP4 is stopped. Normally, the sluice valve 16 after the standby machine BFP15 requires 1 to 2 minutes to open because the large-diameter valve is under high pressure. Therefore, a small-diameter bypass line 17 connecting the front and rear of the gate valve 16 is provided, and the bypass valve 18 is provided there. That is, after opening the bypass valve 18 having a small operating power to minimize the differential pressure across the sluice valve 16, the sluice valve 16 is opened with a smaller torque. As a result, the opening time of the sluice valve 16 after the conventional spare machine BFP15 can be greatly shortened.

In this way, even after the main BFP 4 is stopped, it is possible to supply the water supply from the water supply container 7 to the boiler 5 and, during that time, start up the backup machine BFP 15 and supply the water to the boiler 5 without interruption.

[0011]

[Effect of device]

 As explained above, according to the present invention, it is possible to continuously supply water to the boiler even after the main BFP in the thermal power plant is stopped, and especially when the main BFP in the fluidized bed boiler is stopped, the residual heat quantity of the boiler is reduced. It is possible to prevent the boiler tube from being damaged by and to restart the plant without waiting time.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of an emergency water supply device according to the present invention.

[Explanation of symbols]

 1 ... Steam turbine 3 ... Condenser 4 ... Main boiler feed pump 5 ... Boiler 6 ... Boiler feed pipe 7 ... Water supply container 8 ... Air container 9 ... Compressor 10 ... Control device 11 ... Stop valve 12 ... Water supply valve 17 ... Bypass Pipe 18 ... Bypass valve 19 ... Emergency water supply pipe 20 ... Communication pipe

Claims (1)

[Scope of utility model registration request] 1. A water supply container communicating with a water supply pipe via an emergency water supply pipe, an air container communicating with the water supply container via a communication pipe having a water supply valve and communicating with a compressor via an air pipe. An emergency water supply device comprising: a stop valve provided upstream of the water supply pipe communicating with the water supply container.