JPH0544565B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a burner atomizing steam supply device for atomizing fuel into a boiler by means of steam in a thermal power plant.

BACKGROUND ART FIG. 2 shows a schematic system diagram of a thermal power plant, in which 1 is a boiler, which has a water cooling wall 2, a superheater 3, a reheater 4, and a burner 5. 6 is a high pressure turbine, 7 is a low pressure turbine, and 8 is an auxiliary steam header.

Water cooling wall 2 and heater 3 installed in boiler 1
The steam evaporated and superheated is supplied to the high-pressure turbine 6 to do work. The steam that has completed its work is reheated in a reheater 4 installed in the boiler 1, and is supplied to a low-pressure turbine 7 to do work.

Note that the heat source of the boiler 1 is obtained by burning oil in the burner 5, but the burner 5 requires a steam source for spraying the oil.

FIG. 3 shows a system diagram of a conventional burner spray steam supply system, and the steam pressure required for the burner 5 in the thermal power plant shown in FIG. 2 is extracted from the auxiliary steam header 8 and the superheater inlet header 11. ing. That is, the auxiliary steam line 13 and the superheater inlet header 11 are connected from the auxiliary steam header 8 via the valve 12.
A bleed air line 15 is connected to the burner 5 via a valve 14, and burner atomization steam is obtained through these lines 13, 15 and 19.

Problems with the Prior Art By the way, in such a conventional burner spray steam supply device, steam is taken out from the superheater inlet header 11 located in the middle of the line directly connected from the boiler 1 to the high pressure turbine 6, as shown in FIG. However, since the burner was used as the atomizing steam source, there was a problem in that the efficiency of the unit was reduced.

OBJECT OF THE INVENTION The present invention has been made for the purpose of eliminating the above-mentioned problems.

Means for Solving the Problems In the present invention, in order to solve the above problems,
Piping is provided to communicate the burner spray steam piping and the auxiliary steam header, the boiler's overheated steam system, and the low-temperature reheat steam system, respectively, and when the boiler is started, the burner spray steam piping and the auxiliary steam header are connected to the During load, the burner spray steam piping and boiler superheated steam system are
System switching means is provided to allow independent communication between the burner spray steam piping and the low temperature reheat steam system when the load is high.

Embodiment Hereinafter, an embodiment of the burner spray steam supply device according to the present invention will be described in detail with reference to the system diagram shown in FIG. In FIG. 1, the same parts as in FIGS. 2 and 3 are designated by the same reference numerals.

In the present invention, the following is added to the conventional device. That is, the line 16 from the outlet side of the high-pressure turbine 6 to the reheater 4 is branched, a high-load line 18 is drawn out through a valve 17, and this is connected to a burner spray steam line 19 that connects to the burner 5. . Then, a pressure gauge 20 is installed in the line 8,
Further, a pressure gauge 21 is provided in the line from the superheater inlet header 11 to the valve 14. The output of this pressure gauge 20 is transmitted to a first valve drive device 22 and a second valve drive device 23.
are supplied respectively. The output of the pressure gauge 21 is also supplied to the first valve driving device 22, and a load condition signal is also supplied from a load condition setting device (not shown), and an output signal based on these is supplied to the valves 12 and 14. It will be done. On the other hand, a load condition signal is also supplied to the second valve driving device 23 from a load condition designer (not shown), and an output signal is given to the valve 17.

Next, the effect will be explained.

First, when starting up the boiler, steam is obtained from the auxiliary steam header 8, which is the only part that maintains steam pressure, and is introduced into the burner 5. That is, pressure gauge 2
If the detected value of 1 is low, the valve 12 is opened by the output of the first valve driving device 22, and the auxiliary steam header 8 is connected to the burner spray steam line 19 via the auxiliary steam line 13, and the burner spray is applied to the burner 5. Steam is sent to start the boiler.

After the boiler is started, the steam pressure on the superheater inlet header 11 side increases, and the pressure gauge 2 indicates that it has reached the predetermined pressure.
1, the first valve driving device 22 operates to issue a signal to open the valve 14, and when the valve 14 is opened, the valve 1 on the auxiliary steam line 13 side is activated.
A signal to close valve 12 is issued to close valve 12. That is, the auxiliary steam line 13 is shut off, and the bleed line 15 is connected to the burner atomizing steam line 19. Therefore, when the load is low, the air extracted from the superheater inlet header 11 is sent to the burner 5 as burner atomized steam.

Furthermore, the boiler is normally operated under high load, and when the load is high, the steam pressure in the outlet line 16 of the turbine 6 is detected by the pressure gauge 20, and if this pressure reaches a predetermined pressure, the second valve is activated. The function of the device 23 is to issue a signal to open the valve 17, and when the valve 17 is opened, the first valve drive device 22 closes the valve 14. That is, the bleed air line 15 is shut off and the high load line 18 is connected to the burner atomizing steam line 19. Therefore, when the load is high, the steam that has done work in the turbine 6 is extracted,
It is sent to the burner 5 as burner atomized steam.

Effects of the Invention As detailed above, in the present invention, when the load is low, a part of the high-pressure steam directly sent from the boiler 1 to the high-pressure turbine 6 is extracted and used as burner spray steam, as in the conventional case. During high-load operation, a portion of the steam sent from the boiler to the turbine is not taken out, and the steam that has been used for work in the turbine is used as burner spray steam, improving unit efficiency. In particular, for boilers that are often operated under high load,
The effect will be more pronounced.

Other Embodiments It goes without saying that the present invention is not limited to the above-mentioned embodiment, but can be implemented with various modifications without departing from the scope of the invention. For example, valve 12,
As the valve drive devices 22 and 23 for controlling the valves 14 and 17, a microcomputer or the like can be used as appropriate.

[Brief explanation of drawings]

FIG. 1 is a system diagram showing an embodiment of the burner spray steam supply device according to the present invention, FIG. 2 is a schematic system diagram of a thermal power plant, and FIG. 3 is a system diagram showing a conventional burner spray steam supply device. It is. 1...Boiler, 3...Superheater, 4...Reheater,
5...Burner, 6...High pressure turbine, 7...Low pressure turbine, 11...Superheater inlet header, 12,1
4, 17... Valve, 19... Burner spray steam line, 20, 21... Pressure gauge, 22, 23... Valve drive device.

Claims (1)

[Claims] 1. Provide piping that communicates the burner spray steam piping with the auxiliary steam header, the heating steam system of the boiler, and the low-temperature reheat steam system, respectively, and connect the burner spray steam piping and the auxiliary steam header with the same piping when the boiler is started. A burner characterized by being provided with a system switching means that connects the burner atomizing steam piping and the boiler superheated steam system independently during low load, and the burner atomizing steam piping and the low temperature reheating steam system during high load. Atomizing steam supply device.