JPH06317103A - Steam supply and power generating plant - Google Patents

Abstract

PURPOSE:To operate a steam supply and power generating plant so as to extensively cope with the changes in demands for heat and electricity by utilizing the exhaust from a steam turbine casing as a heat supply source. CONSTITUTION:In a steam turbine 8 in which a high pressure casing 2, an intermediate pressure casing 3, an electric generator 5, and a low pressure casing are constituted on a single axis, the connection between the low pressure casing 4 and the electric generator 5 is interrupted, the total amount of exhaust from the intermediate casing 3 is supplied as heat supply source, and the flowing-in of the exhaust into the low pressure casing 4 is cut off.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to changes in the demand for heat and electricity in equipment that uses the steam extracted from the steam turbine as a heat source for district heating and cooling, process steam, etc. while generating electricity by rotating the steam turbine. The present invention relates to a cogeneration power generation facility capable of operating over a wide range.

[0002]

2. Description of the Related Art FIG. 4 is a system diagram of a combined heat and power generation facility in which extraction steam of a steam turbine is used as process steam. The steam produced by the steam generator 1 is supplied to the high pressure compartment 2 of the steam turbine 8.
After passing through, the steam generator 1 is reheated again to work in the medium-pressure casing 3 of the steam turbine 8 and further in the low-pressure casing 4 to rotate the generator 5. And generate electricity. The steam discharged from the low-pressure casing 4 is converted into water by the condenser 6, and then is supplied to the steam generator 1 by the water supply pump 7. Here, the process steam is extracted from the intermediate paragraph of the steam turbine 8 based on the pressure / temperature of the steam to be used.

[0003]

Since the cogeneration power generation facility can generate not only electricity but also thermal energy at the same time, it has high thermal efficiency when compared with a power generation facility that generates only electricity. . However, the demands for electricity and heat are not constant and always fluctuate, and the conventional technology cannot cope with a wide range of changes in demand for electricity and heat.

[0004]

According to the present invention, the heat supply source of the steam extracted from the steam turbine is determined to be the inlet side or the outlet side of the passenger compartment, so that the heat supply source to the passenger compartment downstream of the heat supplier is determined. The steam inflow was stopped, and the whole amount of steam that passed through the heat supply source was used.

[0005]

[Operation] The combined heat and power generation facility rotates the steam turbine by using the high temperature and high pressure steam from the steam generators such as the reactor and the boiler and the exhaust heat recovery boiler to generate electric energy, and at the same time, the intermediate of the steam turbine. Since the air is extracted from the paragraph and used for heat energy such as district heating and cooling and process steam, it has higher thermal efficiency than the dedicated power generation equipment and dedicated heat supply equipment. However, since the demand for electric energy and the demand for thermal energy change independently depending on the season and the time, the cogeneration system must be operated in accordance with a wide range of demand changes.

Since the conventional combined heat and power generation facility extracts various air from the middle stage of the steam turbine, there are various restrictions as shown in FIG. 3, so that the heat supply amount is only about 40% of the steam amount at the steam turbine inlet. , Cannot be supplied from power generation equipment.

As a countermeasure against this, the exhaust gas from the passenger compartment of the steam turbine or the inlet side is used as a heat supply source, and at the same time, the passenger compartment on the downstream side of the heat supply source is stopped to control the steam amount at the steam turbine inlet. About 90% of the heat supply amount can be supplied from the power generation equipment, enabling a wide range of operation in response to changes in electricity and heat demand.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

The high-temperature and high-pressure steam produced in the steam generator 1 such as a nuclear reactor, a boiler, and an exhaust heat recovery boiler is worked in the high-pressure casing 2 of the steam turbine 8 and then reheated in the steam generator 1. The steam turbine 8 performs work in the medium-pressure casing 3 and further in the low-pressure casing 4, and then the steam is converted into water by the condenser 6, and the water is supplied to the steam generator 1 by the water supply pump 7. Configure the cycle supplied. Electricity is generated by rotating the generator 5 by the rotating force of the steam turbine 8. Further, the heat is adjusted by opening and closing the heat supply valve 10, and the heat is supplied.

The above cycle is constituted until the heat demand corresponds to about 40% of the steam amount at the inlet of the steam turbine 8. When the heat demand exceeds about 40% of the steam amount at the inlet of the steam turbine 8, the cycle will be as follows.

By fully closing the passenger compartment inlet valve 9 and fully opening the heat supply valve 10, the exhaust gas of the medium pressure compartment 3 is supplied with heat, and at the same time, the shafts of the low pressure compartment 4 and the generator 5 are connected. Disconnect the coupling 11 that is doing. As a result, it is possible to meet more heat demand, and at the same time, the low-pressure casing 4 is separated from the generator 5, so that the load on the generator 5 is reduced and the total thermal efficiency of electricity and heat is improved. In addition,
The layout of each compartment of the steam turbine 8 and the generator 5 can be set freely.

Next, another embodiment of the present invention will be described with reference to FIG.

This embodiment shows an example in which the low-pressure compartment 4 is connected to a generator 5 different from the high-pressure compartment 2 and the medium-pressure compartment 3.
Up to about 40% of the steam amount at the inlet of the steam turbine 8, the heat demand is adjusted by opening and closing the heat supply valve 10 to supply heat. Heat demand is steam turbine 8
If the amount exceeds about 40% of the inlet steam amount, the vehicle interior inlet valve 9 is fully closed and the heat supply valve 10 is fully opened, so that the exhaust gas of the medium pressure vehicle compartment 3 is heated at the same time as the low pressure. The generator 5 connected to the passenger compartment 4 and the low-pressure passenger compartment 4 is stopped. As a result, more heat demand can be met. Therefore, the total thermal efficiency of combining electricity and heat is improved. Further, the respective compartments of the steam turbine 8 of each shaft and the disposition of the generator 5 can be freely set. The same applies to the case of two or more axes.

[0014]

According to the present invention, it is possible to expand the operable area of the cogeneration power generation facility using the steam extracted from the steam turbine as a heat supply source, and at the same time, respond to a wide range of demand changes in electric energy and heat energy. can do. Further, since the passenger compartment on the downstream side of the heat supply source is stopped, high thermal efficiency can be obtained.

[Brief description of drawings]

FIG. 1 is a system diagram showing a cogeneration power generation facility that is an embodiment of the present invention.

FIG. 2 is a system diagram showing a cogeneration power generation facility that is another embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a relationship among a steam turbine inlet steam amount, a generator output, and an extraction amount.

FIG. 4 is a system diagram showing a conventional co-generation power generation facility.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Steam generator, 2 ... High pressure compartment, 3 ... Medium pressure compartment, 4 ... Low pressure compartment, 5 ... Generator, 6 ... Condenser, 7 ... Water supply pump, 8
... Steam turbine, 9 ... Inlet valve, 10 ... Heat supply valve, 1
1 ... Coupling.

Front page continuation (72) Inventor Shinichi Hoizumi 3-1-1, Saiwaicho, Hitachi City, Ibaraki Hitachi Ltd., Hitachi Works

Claims (4)

[Claims] 1. A combined heat and power generation facility characterized in that exhaust gas from a passenger compartment of a steam turbine is used as a heat supply source. 2. A combined heat and power generation facility, wherein an inlet of a steam turbine casing is used as a heat supply source. 3. A combined heat and power generation facility characterized in that when the vehicle compartments forming a steam turbine are connected by a single shaft, the flow of steam into the vehicle compartment downstream of the heat supply source is stopped. 4. A combined heat and power generation facility characterized in that when the passenger compartments forming a steam turbine are connected by two or more shafts, the flow of steam into the passenger compartment downstream from the heat supply source is stopped.