JPS6340243B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in steam powered plants, such as steam power plants with multiple units.

FIG. 1 is a system diagram showing a typical configuration of a steam power generation unit. 1 is a boiler for generating steam, and is connected to a high-pressure turbine 3 via a main steam pipe 2. Reference numeral 4 denotes a low-temperature reheating pipe, which guides the steam that has been worked in the high-pressure turbine 3 to the reheater 5. The steam heated in the reheater 5 is led to an intermediate pressure turbine 7 via a high temperature reheat pipe 6, and the steam that has done work here is further introduced to a low pressure turbine 9 via a crossover pipe 8. The steam expanded by doing work in the low pressure turbine 9 is discharged to the condenser 12 through the exhaust port 10 and becomes condensed water. 11 is coupled to the shafts of the high pressure turbine 3, the intermediate pressure turbine 7 and the low pressure turbine 9,
A generator is driven by these turbines.

The condensate from the condenser 12 is pressurized and heated by a pump and feed water heater (not shown), and then flows into the condensate pipe 13.
is returned to boiler 1 through the

On the other hand, the main steam pipe 2 and the low temperature reheat pipe 4 are connected to the pressure reducing valve 15.
are connected by a high-pressure bypass pipe 14 having
When the pressure reducing valve 15 is opened, the high temperature and high pressure main steam is reduced in pressure, further reduced in temperature by an attemperator (not shown), and introduced into the reheater 5 bypassing the high pressure turbine 3. Further, 16 is a low-pressure bypass pipe that is branched from the high-temperature reheat pipe 6, bypasses the intermediate-pressure turbine 7 and the low-pressure turbine 9, and guides the high-temperature reheated steam to the condenser 12, and a pressure reducing valve 17 is provided in the middle. ing.

In a steam power generation unit configured in this way,
The main steam generated in the boiler 1 first drives the high-pressure turbine 3, and the exhaust gas is reheated to drive the intermediate-pressure turbine 7 and the low-pressure turbine 9, thereby driving the generator 11 as a load.

By the way, there are two purposes for providing the high pressure bypass pipe 14 and the low pressure bypass pipe 16.
One is to allow the steam to quickly bypass each turbine 3, 7, 9 and flow to the condenser 12 during load shedding; By starting and operating the boiler 1 using the 14 and low-pressure bypass pipe 16, the main steam temperature and pressure conditions necessary for starting the turbine are prepared in advance, and the start-up time as a unit is reduced. It is to shorten.

To reduce the startup time of this unit,
It is necessary to quickly create a vacuum in the condenser 12. In other words, before starting the turbine, it is necessary to remove the air accumulated in the condenser and turbine, but in order to remove this air, a steam-driven type A starting ejector is used, for which 14-20Kg/ ^cm2 g
A certain amount of steam pressure is required. In other words, the starting ejector cannot be used until this steam pressure is reached, and it is necessary to wait until the steam pressure from the boiler 1 increases. Therefore, a separate auxiliary boiler was sometimes installed to obtain the steam to drive the startup ejector.

The above is an explanation for the case where there is one steam power generation unit, but in a steam power generation plant equipped with multiple steam power generation units, the starting ejector of the unit to be started is supplied with steam from other operating units. It was proposed to supply

That is, FIG. 2 shows a system diagram of a conventionally proposed steam power generation plant having a plurality of steam power generation units, in which 21 is a boiler, 22 is a main steam pipe, 23 is a turbine, 24 is a generator, 25
is a condenser. Although these are shown as simplified configurations for the steam power generation unit shown in FIG. 1, they respectively correspond to those shown in FIG. Further, 26 is a steam-driven starting ejector, to which an ejector drive steam pipe 27 branched from the main steam pipe 22 is connected, and an air extraction pipe 28 is connected between it and the condenser 25. ing. 29 is a valve.

Note that the ejector drive steam pipes 27 of each steam power generation unit are connected to a common common steam pipe 3 via a valve 30.
1. Here, the respective steam power generation units are referred to by symbols A, B, . . . , E, and the configuration of each unit A, B, . . . E is the same.

In such a power plant, A to E
It is assumed that among the five units up to this point, only unit E is in operation, and the other four units A to D are stopped. Under such conditions, when attempting to start unit A, the common steam pipe 31
By introducing the steam from unit E into the ejector drive steam pipe 27 of unit A through the steam pipe 27 and operating the starting ejector 26 of unit A, early starting of unit A is achieved. In addition, unit B
-E is in operation and when it is desired to start unit A, it is sufficient to supply steam from any one of units B to E to unit A, and the selection is made by selecting the valve 30.

By the way, in such a conventional steam power generation plant having multiple units, each unit is connected by a common steam pipe 31, but since the common steam pipe 31 is for passing high temperature and high pressure steam, the piping route is different. The drawback was that it was complicated and costly.
In addition, only one ejector can be used for starting, and it cannot contribute much to shortening the starting time.

The present invention has been made with the object of eliminating such conventional drawbacks.

That is, the present invention includes at least a boiler for steam generation, a turbine driven by steam supplied from the boiler, a load coupled to the turbine, a condenser from which steam that has completed work in the turbine is discharged, and In a steam-driven plant equipped with a plurality of units each having a starting air extractor, a common air pipe is connected to the air intake side of the starting air extractor of each unit, and a common air pipe is connected to the condenser side with this connection in between. and a valve is provided in each air extraction pipe on the side of the starting air extractor, and the valve is controlled so that the starting air extractor in operation among the plurality of units is used to start a stopped unit. A steam-driven plant characterized by:

An embodiment of the steam-driven plant according to the present invention will be described in detail below with reference to FIG. Note that in FIG. 3, the same parts as those in FIG. 2 are designated by the same reference numerals, so the explanation of those parts will be omitted.

The present invention is to connect the low-temperature air extraction pipes of each unit with a common air pipe, instead of connecting the high-temperature, high-pressure ejector drive steam pipes of each unit with a common steam pipe as in the past. It is characterized by

That is, a common air pipe 32 is connected to the air extraction pipe 28 of each unit, and valves 33 and 34 are arranged in the air extraction pipe 28 on the condenser 25 side and the starting ejector 26 side, respectively, with this connection in between. are doing. Therefore, for example, in the case of a steam power generation plant having five units A to E, if four units B to E are in operation and unit A is to be started, the condenser 25 of unit A is activated. To create a vacuum, unit B~ is operated by operating valves 33 and 34.
Four starting ejectors 26 of E can be used. Therefore, condenser 2 of the unit to be started
The time required to raise the vacuum of No. 5 is dramatically shortened, and the unit can be started up in a short time.

In this way, the present invention is based on the unique idea of not using the ejector of the unit to be started, but using the ejector of another unit in operation for starting, which reduces the start-up time. can be shortened. Furthermore, since the low-temperature air extractor 28 only needs to be connected to the common pipe 32, this piping route can also be easily installed under the turbine operation floor, etc., which has the advantage of easy work and low cost. There is.

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.

[Brief explanation of drawings]

Fig. 1 is a system diagram showing the configuration of a steam power generation unit, Fig. 2 is a system diagram showing a conventional steam power generation plant having a plurality of steam power generation units, and Fig. 3 is a system diagram showing an embodiment of the present invention. be. 21... Boiler, 22... Main steam pipe, 23...
Turbine, 24... Generator, 25... Condenser, 2
6... Starting ejector, 27... Ejector steam pipe, 28... Air extraction pipe, 29, 33, 34...
Valve, 32... common air pipe.

Claims (1)

[Claims] 1 At least a steam generation boiler, a turbine driven by steam supplied from the boiler,
In a steam-driven plant comprising a plurality of units having a load coupled to the turbine, a condenser from which the steam that has completed work in the turbine is discharged, and a starting air extractor, the starting air extraction for each of the units is provided. A common air pipe is connected to the air intake side of the vessel, and a valve is provided in each of the air extraction pipes on the condenser side and the startup air extractor side with this connection part in between,
A steam-driven plant characterized in that the valve is controlled so as to start a stopped unit using a starting air extractor that is in operation among the plurality of units.