JPH04127866A - Combined cycle power plant - Google Patents

Abstract

PURPOSE:To install a combined cycle power plant requiring no smokestack by feeding high temperature waste gas containing CO2 produced through blowing of combustion oxygen into a combustor to a heat accumulator thereby collecting waste gas from a combined cycle power plant incorporating an MHD generating system entirely in the form of liquefied CO2. CONSTITUTION:A separator 20 separates the air into oxygen and nitrogen by means of an molecular adsorbent and thus separated oxygen is then blown into a combustor 21 where it is burnt together with fuel to produce high temperature waste gas containing CO2. The high temperature waste gas is then fed to a heat accumulator 23 where it is heated and then fed to an MHD generator 24 in order to generate power. The waste gas is heat exchanged with rare gas in the heat accumulator 23 and then fed to a gas turbine 29 which is thereby driven to drive a generator G2 and generate power. The waste gas is then fed from a heat recovery boiler 28 to a CO2 pressurizing unit 31 coupled through a gas compressor 30 with the gas turbine 29 and the CO2 pressurizing unit 31 pressurize the waste gas to produce liquefied CO2 which is then collected and discarded to the ocean or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a magnetic fluid (Magneto Hydro D).
The present invention relates to a combined thermal power generation device incorporating power generation (ynalcs).

[Conventional technology]

Pressurized fluidized bed combustion boiler (P F B C) for MHD power generation
An overview of a conventional example of a combined cycle thermal power generation device incorporated in a conventional power generating system will be explained with reference to the flow sheet shown in FIG.

As shown in FIG. 2, the combined thermal power generation system includes a fuel combustion system using a combustor, an MHD power generation system using a rare gas such as helium or argon, a steam turbine power generation system, and a PFBC gas turbine power generation system.

The combustion system uses a high-load slag tap type combustor 1 to generate fuel (coal, coal gas, natural gas, etc.) to produce high-temperature (approximately 2000℃) exhaust gas.

At this time, in order to control NOx contained in the exhaust gas, a two-stage combustion method is used in the PFBC II of the gas turbine power generation system under fuel excess conditions.

MHD power generation system using rare gas (closed cycle MID)
Power generation system): (a) The above exhaust gas is put into the heat storage device 2 and the rare gas, which is the working gas for MHD power generation, is heated to about 2000°C.

(b) The heated rare gas enters the MHD generator 3 and generates electricity.

(c) The rare gas leaving the MHD generator 3 passes through the high temperature rare gas boiler 4, the regenerative heat exchanger 5, and the low temperature rare gas boiler 6, and then enters the rare gas turbine 7 (in conjunction with the steam turbine 8).

The high-temperature and low-temperature rare gas boilers 4.6 are not directly involved in MHD power generation using rare gas, but are used for heat exchange in a steam turbine power generation system, which will be described later.

(d) The rare gas leaving the rare gas turbine 7 is transferred to the regenerative heat exchanger 5.
The heat is then preheated and returned to the heat storage device 2.

The steam turbine power generation system includes the rare gas turbine via and the generator G in the steam turbine 8.
(a) Steam turbine 8 - Condenser 9 - Low temperature rare gas boiler 6
(The rare gas temperature in the boiler 6 is close to room temperature) - High temperature rare gas boiler 4 (Uses the rare gas temperature after MHD power generation action) - Circulation path of the steam turbine 8, (b) Steam turbine 8 - Condenser 9 -Heat recovery boiler 16 (
Utilizing the recovered heat of the exhaust gas after the gas turbine action of the gas turbine power generation system described later) - the circulation path of the steam turbine 8, and the circulation path of the steam turbine 8, it operates by two circulation paths to drive the generator G1 and generate electricity.

(4) The PFBC gas turbine power generation system consists of (a) fluidized combustion of limestone (CaCO3) desulfurization agent together with fuel (coal) in the PFBCll installed in the pressure vessel 10;
Generate exhaust gas at a temperature of 0 to 900°C and 10 to 16 atm.

(b) After the exhaust gas enters the desulfurization device 12 and undergoes precise desulfurization, it enters the gas turbine 13 and drives the turbine 13.

(C) By driving the gas turbine 13, the turbine 13
The generator G2 connected to the combustor 1 is driven to generate electricity, and the air compressor 14 is operated to supply pressurized air to the PFBCll and the combustor 1.

(d) The exhaust gas that exits the gas turbine 13 enters the exhaust heat recovery boiler 16, and a part of the exhaust gas whose heat is recovered (this heat is used to drive the steam turbine 8) is sent to the gas turbine 13 by the air compressor 14. The air is supplied to the combustor 1 as high-temperature combustion air through the gas compressor 15 connected thereto, and the other part is released into the atmosphere from the chimney 17 as exhaust gas containing CO2.

[Problem to be solved by the invention]

The conventional combined cycle power generation device has good overall power generation efficiency (
It has a net transmission efficiency of 50% or more) and has good environmental characteristics (
SO, concentration 50ppm or less, NOx concentration 40ppm
(hereinafter, dust concentration 10mg/Nm, below), 1
It is possible to replace base firepower, middle firepower, and aging firepower with units of about 200 to 500 MW.

However, the CO2 generated during fossil combustion was released into the atmosphere without any treatment.

Since CO2 is one of the substances that cause global warming, there is a growing demand for the treatment of CO2, as awareness of the issue of global environmental conservation is increasing and efforts are being made to regulate CO2 emissions.

The present invention was made in view of the above circumstances, and an object of the present invention is to recover all the exhaust gas from fuel combustion of a combined cycle power generation system incorporating MHD power generation as liquefied carbon dioxide gas, and to provide a smokeless combined cycle power generation system. It is something to do.

[Means to solve the problem]

In order to achieve the above object, the combined thermal power generation device of the present invention includes an oxygen separation device and a combustor, a high oxygen combustion system that burns fuel together with combustion oxygen, and a high-oxygen combustion system that burns the fuel together with combustion oxygen, and a high-oxygen combustion system that burns CO2 from the combustor. an MHD power generation system that includes a heat storage device into which high-temperature exhaust gas containing gas is introduced, an MHD generator interposed in a rare gas circulation path that exchanges heat within the heat storage device, and exhaust gas that returns from the heat storage device to the combustor via a gas turbine. A circulation path between a gas turbine power generation system having a circulation path, a heat recovery boiler interposed in the exhaust gas circulation path of the gas turbine power generation system, a high temperature rare gas boiler interposed in the rare gas circulation path of the MHD power generation system, and a steam turbine. and a CO2 liquefaction system including a CO2 pressurizer that introduces exhaust gas exiting the heat recovery boiler of the gas turbine power generation system and converts it into liquefied carbon gas.

Oxygen for combustion is produced by a device that separates air into oxygen and nitrogen using a molecular adsorbent such as PSA.

[For production]

C burned at high temperature by blowing combustion oxygen into the combustor
High-temperature exhaust gas containing O2 is sent to a heat storage device, and MHD power generation is performed through a rare gas circulation path in which heat is exchanged within the heat storage device.

Gas turbine power generation is performed using the exhaust gas that exits the heat storage device.

Steam turbine power generation is performed through a steam circulation path that circulates between the heat recovery boiler of the gas turbine power generation system and the high temperature rare gas boiler of the MHD power generation system.

Then, the exhaust gas exiting the heat recovery boiler is led to the 002 pressurizer, where it is converted and recovered into liquefied carbon dioxide gas.

〔Example〕

Embodiments of the present invention will be described with reference to the drawings.

As shown in Figure 1, a combined cycle power generation system consists of a high-oxygen combustion system using a combustor, an MHD power generation system using rare gases such as helium and argon, a steam turbine power generation system, a gas turbine power generation system using exhaust gas, and a CO2 liquefaction system. It consists of a system.

(1) The high oxygen combustion system is a device that separates air into oxygen and nitrogen using molecular adsorbents, etc.2
0 (e.g., P S A -PressureSwin
The oxygen separated by G Absorber is blown into the combustor 21 as combustion oxygen, and the oxygen separated by the fuel (coal, LNG
, heavy oil, etc.) to produce high-temperature exhaust gas containing CO□.

In this case, since high oxygen combustion occurs, a combustion temperature of approximately 2000° C., which is higher than that of normal pulverized coal combustion, is obtained.

When the fuel contains ash such as coal, a deashing device F22 is installed downstream of the combustor 21 to reduce the soot and dust concentration in the exhaust gas.

(2) MHD power generation system using rare gas (closed cycle MHD power generation system): (a) High-temperature exhaust gas emitted from the combustor 21 is put into the heat storage device 23 (after passing through the deashing device 22 if necessary), and the MH
The rare gas that is the working gas for D power generation is heated to about 2000''C.

(b) The heated rare gas enters the MHD generator 24 and generates electricity.

(e) The rare gas exiting the MHD generator 24 passes through the high temperature rare gas boiler 25 and enters the rare gas turbine 26.
6 and returns to the heat storage device 23.

Note that the high-temperature rare gas boiler 25 is not directly involved in MHD power generation, but is used for heat exchange in the steam turbine power generation system.

(8) In the steam turbine power generation system, the steam turbine 27 is connected to the rare gas turbine 26 and the generator G1, and the steam turbine 27 is connected to the steam turbine 27 - heat recovery boiler 28 (gas turbine operation - High temperature rare gas boiler 25 (uses rare gas temperature after MHD power generation operation) - Operates by the circulation path of the steam turbine 27 and works in conjunction with the rare gas turbine 26 to drive the generator G1 and generate electricity.

(4) In the gas turbine power generation system using exhaust gas, (a) exhaust gas that has exchanged heat with rare gas in the heat storage device 23 is transferred to the gas turbine
9 to drive the turbine 29 and also drive the generator G2 connected to the turbine 29 to generate electricity.

(b) The exhaust gas leaving the gas turbine 29 is sent to the heat recovery boiler 2
8 (recovered heat is used for heat exchange in the steam turbine system),
A portion of the heat-recovered exhaust gas enters the combustor 21 and is used to control combustion temperature.

(5) The CO2 liquefaction system converts the exhaust gas other than the one that exits the heat recovery boiler 28 and is used for the combustion temperature control of the combustor 21 into a CO□ addition system connected to the gas turbine 29 via the gas compressor 30. It is put into a pressure vessel 31 and pressurized, recovered as liquefied carbon dioxide, and disposed of in the ocean or the like.

The power costs required for the oxygen/nitrogen separator and CO2 pressurizer for the combined thermal power generation system made up of the above prefectures are about 20% of the total.
Since it is about 0%, the total power generation efficiency is expected to be about 40% in transmission net efficiency, and it is smokeless with no CO2 released into the atmosphere and does not require a chimney.

〔effect〕

The present invention has the following effects.

(a) Since all the exhaust gas from the combustor of the combined cycle power generation device is recovered as liquefied carbon dioxide, it effectively functions to solve global environmental conservation problems such as global warming.

(b) Since it incorporates MHD power generation, a highly efficient power generation technology, the overall power generation efficiency can be expected to be approximately 40% at the transmission end.

(C) Since it is a combustion system with high enzyme combustion, the gas turbine power generation system eliminates the need for other combustion systems such as conventional PFBC.
Equipment costs are reduced.

[Brief explanation of the drawing]

FIG. 1 is a flow sheet of an embodiment of the combined thermal power generation device according to the present invention, and FIG. 2 is a flow sheet of a conventional example. 20...Oxygen/nitrogen separation device, 21...Combustor, 2
3... Heat storage device, 24... MHD generator, 25...
High temperature rare gas boiler, 26... rare gas turbine, 27...
...Steam turbine, 28...Heat recovery boiler, 29...
・Gas turbine, 30...Gas compressor, 31...C
O2 pressurizer, G1, G2... generator.

Claims (2)

[Claims] (1) A high-oxygen combustion system that has an oxygen separation device and a combustor, and burns fuel together with combustion oxygen; a heat storage device that introduces high-temperature exhaust gas containing CO_2 emitted from the combustor; an MHD power generation system having an MHD generator interposed in a rare gas circulation path for heat exchange; a gas turbine power generation system having an exhaust gas circulation path from the heat storage device to the gas turbine and returning to the combustor; and the gas turbine power generation system. A heat recovery boiler interposed in the exhaust gas circulation path of the MHD power generation system, a high temperature rare gas boiler interposed in the rare gas circulation path of the MHD power generation system, a steam turbine power generation system having a circulation path with the steam turbine, and a heat recovery boiler of the gas turbine power generation system. A combined thermal power generation device comprising: a CO_2 liquefaction system having a CO_2 pressurizer that introduces exhaust gas exiting a recovery boiler and converts it into liquefied carbon dioxide gas. (2) The combined thermal power generation device according to claim (1), wherein the oxygen separation device separates air into oxygen and nitrogen using a molecular adsorbent or the like.