JP2001152810A - Energy-recovery apparatus for supercritical fluid thermal reaction plant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an energy-recovery apparatus for a supercritical fluid thermal reaction plant for recovering the energy of a supercritical fluid after reaction by performing an oxidizing combustion reaction with fuel and pure oxygen in supercritical water. SOLUTION: In this energy-recovery apparatus for a supercritical fluid thermal reaction plant, a supercritical fluid thermal reaction part 2, an energy recovering part 3 and a condenser 15 are assembled with a fuel-supplying part 1, an oxidizing combustion reaction is conducted by fuel from the fuel-supplying part 1 and oxygen in the supercritical fluid thermal reaction part 2 to generate a supercritical fluid. After the energy of the supercritical fluid generated from the supercritical fluid thermal reaction part 2 is converted into power by the energy-recovering part 3, it is condensed by the condenser 15, and is returned to a raw fuel reserve tank 5 of the fuel-supplying part 1 as sodium sulfation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a supercritical fluid thermal reaction in which a low-grade fuel is oxidized and combusted with a supercritical fluid, and the heat energy of the supercritical fluid after the oxidized combustion reaction is effectively recovered and utilized. The present invention relates to a plant energy recovery device.

[0002]

2. Description of the Related Art In the recent environmental field, the properties of supercritical fluids are skillfully used to decompose hardly decomposable substances, such as ion-exchange resins and vinyl chloride, and harmful compounds, such as PCBs, chlorofluorocarbons, and dioxins. Research to detoxify such substances has been promoted, and it is expected that they will be put to practical use.

[0003] Here, the supercritical fluid is defined as a critical pressure 22.
A fluid containing water at a temperature of 04 MPa and a critical temperature of 374.1 ° C. or higher. This supercritical fluid has a high dissolving ability for dissolving harmful substances and has a high property, but has an extremely low dissolving ability for inorganic substances such as salts.

[0004] A technique of skillfully utilizing a supercritical fluid having such an attribute, adding a supercritical fluid to a molten plastic material, liquefying the plastic in a supercritical state, and recovering the oily fluid is known, for example. It is disclosed in JP-A-6-279762 and JP-A-10-67991.

[0005]

However, in a power plant, there is a concern that high-grade fossil fuels such as LNG (liquefied natural gas) and high-quality coal will be depleted. For example, a coal gasification combined cycle power plant using a low-grade fuel of No. 1 has entered a test operation and is approaching practical use.

[0006] A coal gasification combined cycle power generation plant pulverizes low-grade coal, gasifies the pulverized coal in a gasifier, desulfurizes and dedusts the gaseous fuel, and supplies it to a gas turbine combustor. Although it generates combustion gas, the amount of gas fuel required for a gas turbine combustor is enormous, several hundred tons per hour. For this reason, the capacity of desulfurizers and dust collectors that remove sulfur and dust contained in the gas fuel generated in the gasifier becomes inevitably large.
There was a problem that it became expensive in terms of cost.

[0007] Further, even if a coal gasification combined cycle power plant is provided with a desulfurization device and a dust collection device to remove sulfur and dust contained in gas fuel generated from a gasification furnace, the current technology does not. It cannot be sufficiently removed, and NOx or SO
x and the like were contained in a relatively large amount, which caused environmental pollution.

For this reason, in the field of power plants, it has been desired to realize a new technology capable of reliably removing environmental pollutants such as NOx and SOx in place of a desulfurization device and the like.

The present invention has been made based on such background art, and NOx and SOx which cause environmental pollution are considered.
A supercritical fluid thermal reaction plant that reliably decomposes and removes environmental pollutants such as supercritical fluids using a supercritical fluid, and effectively recovers and uses the thermal energy of the supercritical fluid after reacting with NOx, SOx, etc. An object is to provide an energy recovery device.

[0010]

According to a first aspect of the present invention, there is provided an energy recovery apparatus for a supercritical fluid thermal reaction plant according to the present invention. A supercritical fluid thermal reaction section that generates a supercritical fluid by an oxidative combustion reaction with oxygen from the system, and converts the energy of the supercritical fluid generated from the supercritical fluid thermal reaction section into power, and converts the power to the power described above. An energy recovery unit to be applied to each of a booster pump, a raw fuel transfer pump, and a compressor of an oxygen supply system of a fuel supply unit, and a supercritical fluid discharged from the energy recovery unit to condensed water to convert the raw fuel to the fuel supply unit And a condenser for returning to the storage tank.

Further, in order to achieve the above object, the energy recovery apparatus for a supercritical fluid thermal reaction plant according to the present invention, wherein the supercritical fluid thermal reaction section is formed in a cylindrical shape. And a cylindrical steam generating section formed concentrically outside the reaction vessel.

Further, in order to achieve the above object, the energy recovery apparatus for a supercritical fluid thermal reaction plant according to the present invention is configured such that the supercritical fluid thermal reaction section is connected to the fuel supply section. And a solid residue storage tank for storing a solid generated after an oxidative combustion reaction between the fuel and oxygen from the oxygen supply system to generate a supercritical fluid.

[0013] In order to achieve the above object, in the energy recovery apparatus for a supercritical fluid thermal reaction plant according to the present invention, the fuel is a slurry-like low-grade coal. It is characterized by the following.

According to a fifth aspect of the present invention, there is provided an energy recovery apparatus for a supercritical fluid thermal reaction plant, wherein a steam generator supplies steam to a steam turbine. A steam port, which is provided with a water supply port for receiving the water supply and a neutralization solution port for receiving the neutralization solution from the condenser by condensing steam for driving the generator by performing expansion work in the steam turbine to supply water. Things.

According to a sixth aspect of the present invention, an energy recovery apparatus for a thermal reaction plant for a supercritical fluid according to the present invention comprises: A screw engine that converts the energy of the supercritical fluid into power.

According to a seventh aspect of the present invention, there is provided an energy recovery apparatus for a thermal reaction plant for a supercritical fluid according to the present invention. It is divided into a high-pressure screw engine, a medium-pressure screw engine, and a low-pressure screw engine arranged in a cascade.

In order to achieve the above object, the energy recovery apparatus for a supercritical fluid thermal reaction plant according to the present invention is configured such that the high-pressure screw engine is provided with a fuel supply unit for transferring raw fuel. The pump is connected by a shaft power transmission unit.

According to a ninth aspect of the present invention, there is provided an energy recovery apparatus for a supercritical fluid thermal reaction plant, the medium pressure screw engine comprising a booster pump for a fuel supply unit. Are connected by a shaft power transmission unit.

Further, in order to achieve the above object, the energy recovery apparatus for a supercritical fluid thermal reaction plant according to the present invention is configured such that the low-pressure screw engine comprises an oxygen supply system compressor and At least one of the generators is connected by a shaft power transmission unit.

In order to achieve the above object, the energy recovery apparatus for a supercritical fluid thermal reaction plant according to the present invention has a high-pressure screw engine, a medium-pressure screw engine and a low-pressure screw engine. Has a pressure regulating valve for regulating the pressure of the supercritical fluid supplied from the supercritical fluid thermal reaction section at each inlet side.

In order to achieve the above object, in the energy recovery apparatus for a supercritical fluid thermal reaction plant according to the present invention, the condenser includes a superconducting fluid supplied from an energy recovery section. It contains a heat exchange unit for condensing a critical fluid with a neutralizing solution.

Further, in order to achieve the above object, in the energy recovery apparatus for a supercritical fluid thermal reaction plant according to the present invention, the neutralizing solution is sodium hydroxide.

Further, in order to achieve the above object, the energy recovery apparatus for a supercritical fluid thermal reaction plant according to the present invention, as described in claim 14, transfers the energy from the condenser to the raw fuel storage tank of the fuel supply section. The condensed water to be returned contains sodium sulfate.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment of an energy recovery apparatus for a supercritical fluid thermal reaction plant according to the present invention will be described with reference to the drawings and reference numerals attached to the drawings.

FIG. 1 is a schematic system diagram showing an embodiment of an energy recovery apparatus for a supercritical fluid thermal reaction plant according to the present invention.

The supercritical fluid thermal reaction plant according to the present embodiment has a configuration in which an energy recovery unit 3 and a condenser 15 are combined with a fuel supply unit 1 and a supercritical fluid thermal reaction unit 2.

The fuel supply unit 1 includes a raw fuel production tank 4, a raw fuel storage tank 5, a booster pump 6, and a raw fuel transfer pump 7, and for example, a low-grade coal produced in the raw fuel production tank 4 is slurried. The raw slurry is stored in the raw fuel storage tank 5, and the stored low-grade slurry-like coal is pressurized by the booster pump 6 and the raw fuel transfer pump 7 and supplied to the supercritical fluid thermal reactor 2.

The fuel supply unit 1 includes an oxygen supply system 8 and a compressor 9, and supplies pure oxygen from the oxygen supply system 8 to the compressor 9.
The high pressure oxygen is supplied to the supercritical fluid thermal reaction section 2.

On the other hand, the supercritical fluid thermal reaction section 2 performs an oxidative combustion reaction between, for example, slurry-like low-grade coal supplied from the fuel supply section 1 and high-pressure pure oxygen from the oxygen supply system 8 to form a supercritical fluid. Reaction vessel 10 which generates high heat by heating
And a cylindrical steam generating section 11 formed concentrically outside the reaction vessel 10.

The steam generator 11 is provided with a steam port 13 for supplying steam to a steam turbine (both not shown) for driving a generator, a water supply port 14 for receiving water from the steam turbine, and a condenser 15 for neutralization. A neutralizing solution port 17 for receiving a neutralizing solution from a solution supply line 16 is provided.

The supercritical fluid thermal reaction section 2 includes a solid residue storage tank 12 for storing solids generated after oxidizing and combusting low-grade slurry and high-pressure pure oxygen in a reaction vessel 10. It has.

On the other hand, the energy recovery unit 3 converts the supercritical fluid generated when the slurry-like low-grade coal and high-pressure pure oxygen are subjected to an oxidative combustion reaction in the supercritical fluid thermal reaction unit 2 into power. , To the condenser 15.

The condenser 15 is provided with a neutralizing solution inlet 19, a non-condensable fluid outlet 20, and a condensed fluid outlet 2 in a cylindrical container 18.
1 and a heat exchange part 22 inside the container 18.
After the supercritical fluid from the energy recovery unit 3 and the neutralization solution such as sodium hydroxide from the neutralization solution inlet 19 are heat-exchanged in the heat exchange unit 22 to condense the supercritical fluid. , Fuel supply unit 1 as sodium sulfate
The raw fuel storage tank 5 is returned.

The condenser 15 separates a fluid generated when the supercritical fluid is condensed in the heat exchange section 22 into a non-condensable fluid and a condensed fluid, and discharges the non-condensable fluid into the non-condensable fluid outlet 20. After supplying the condensed fluid to another device via the condensed fluid discharge port 21 and the neutralized solution such as sodium hydroxide in the heat exchange unit 22, Is supplied to the steam generation section 11 of the supercritical fluid thermal reaction section 2 through the neutralization solution supply line 16 to neutralize the steam.

On the other hand, the energy recovery unit 3 using the supercritical fluid generated from the supercritical fluid thermal reaction unit 2 as an energy source includes a high-pressure screw engine 23, a medium-pressure screw engine 23 arranged in a cascade along the flow of the supercritical fluid. Engine 24,
A low-pressure screw engine 25 is provided, which extracts power while reducing the pressure of the supercritical fluid to atmospheric pressure, and transfers the power via a shaft power transmission unit 26 such as a rotary shaft to the booster pump 6 of the fuel supply unit 1. The fuel is supplied to each of the fuel transfer pump 7 and the compressor 9. The high-pressure screw engine 23 is mechanically connected to the raw fuel transfer pump 7, the medium-pressure screw engine 24 is connected to the booster pump 6, and the low-pressure screw engine 25 is connected to the compressor 9 via a shaft power transmission unit 26. I have. In this embodiment, the high-pressure screw engine 23, the medium-pressure screw engine 24, and the low-pressure screw engine 25 are mechanically connected to the booster pump 6, the raw fuel transfer pump 7, and the compressor 9, respectively. Not limited to the example, FIG.
The generator 27 may be directly connected to the shaft as shown in FIG.

As shown in FIG. 2, the energy recovery unit 3 has inlets of a high-pressure screw engine 23, a medium-pressure screw engine 24, and a low-pressure screw engine 25 arranged in a cascade along the flow of the supercritical fluid. Pressure regulating valves 28a, 28b, 28c are provided on the side, and the pressure of the supercritical fluid is adjusted according to the loads of the raw fuel transfer pump 7, the booster pump 6, and the compressor 9.

In the energy recovery apparatus of the supercritical fluid thermal reaction plant having such a configuration, for example, slurry-like low-grade coal and high-pressure oxygen from the fuel supply unit 1
Oxidation and combustion reaction takes place in the reaction vessel 10 of the supercritical fluid thermal reaction section 2, and environmental pollutants such as sulfur and nitrogen are decomposed and removed by the ultra-high temperature heat of the supercritical fluid generated at that time.
The super high temperature heat guides the steam from the water supply port 14 in the steam generation unit 11 to evaporate the water supply into steam.
3 to a steam turbine (not shown) to perform expansion work, and the generated power drives a generator (not shown).

The reaction vessel 1 of the supercritical fluid thermal reaction section 2
The supercritical fluid generated at 0 is supplied to the high-pressure screw engine 23, the medium-pressure screw engine 24,
While flowing through each of the low-pressure screw engines 25 in order, pressure is adjusted by the pressure adjusting valves 28a, 28b, and 28c to generate power, and the power is used as a drive source for the raw fuel transfer pump 7, the booster pump 6, the compressor 9, and Generator 27
Is driven to rotate.

The supercritical fluid generated by the energy recovery unit 3 is condensed by heat exchange with, for example, a neutralized solution of sodium hydroxide in the heat exchange unit 22 of the condenser 15 and then condensed with, for example, sodium sulfate ( Fuel supply unit 1 again
Is returned to the raw fuel storage tank 5 and reused as part of the fuel.

As described above, in the present embodiment, the fuel supply unit 1
For example, a fuel such as low-grade coal in the form of slurry and high-pressure oxygen are supplied to the supercritical fluid thermal reaction section 2, where the supercritical fluid generated during the oxidative combustion reaction is an environmental pollutant such as sulfur or nitrogen. And the supercritical fluid was supplied to the energy recovery unit 3 to generate power, and the power used to drive the raw fuel transfer pump 7, booster pump 6, compressor 9 and generator 27 to rotate. In addition, it is possible to effectively utilize energy, improve the thermal efficiency of the plant, and reduce fuel consumption.

[0041]

As described above, the energy recovery apparatus for a supercritical fluid thermal reaction plant according to the present invention includes the supercritical fluid generated in the oxidative combustion reaction between low-grade fuel and high-pressure oxygen, which is included in the fuel. It decomposes and removes environmental pollutants such as sulfur, and generates power using the thermal energy, and supplies the power to the raw fuel transfer pump, booster pump, compressor, and generator of the fuel supply unit. Since the rotary drive is performed, the energy can be effectively used, and the plant efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic system diagram showing an energy recovery device of a supercritical fluid thermal reaction plant according to the present invention.

FIG. 2 is a partially enlarged view of an energy recovery unit shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fuel supply part 2 Supercritical fluid thermal reaction part 3 Energy recovery part 4 Raw fuel production tank 5 Raw fuel storage tank 6 Booster pump 7 Raw fuel transfer pump 8 Oxygen supply system 9 Compressor 10 Reaction vessel 11 Steam generation part 12 Solid residue Material storage tank 13 Steam port 14 Water supply port 15 Condenser 16 Neutralizing solution supply line 17 Neutralizing solution port 18 Container 19 Neutralizing solution inlet 20 Non-condensable fluid outlet 21 Condensed fluid outlet 22 Heat exchanger 23 High pressure screw engine 24 Medium-pressure screw engine 25 Low-pressure screw engine 26 Shaft power transmission unit 27 Generator 28a, 28b, 28c Pressure regulating valve

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02C 3/20 B09B 3/00 304L

Claims (14)

[Claims] 1. A supercritical fluid thermal reaction unit that generates a supercritical fluid by an oxidative combustion reaction between fuel from a fuel supply unit and oxygen from an oxygen supply system, and a supercritical fluid thermal reaction unit generated from the supercritical fluid thermal reaction unit. An energy recovery unit that converts the energy of the critical fluid into power and supplies the power to each of the booster pump, the raw fuel transfer pump, and the compressor of the oxygen supply system of the fuel supply unit. A condenser for converting the critical fluid into condensed water and returning the condensed water to the raw fuel storage tank of the fuel supply unit. 2. The supercritical fluid thermal reaction section comprises a cylindrical reaction vessel and a cylindrical steam generation section formed concentrically outside the reaction vessel. 1
An energy recovery apparatus for a supercritical fluid thermal reaction plant according to claim 1. 3. The supercritical fluid thermal reaction unit is a solid residue that stores a solid produced after an oxidative combustion reaction between fuel from a fuel supply unit and oxygen from an oxygen supply system to generate a supercritical fluid. The energy recovery apparatus for a supercritical fluid thermal reaction plant according to claim 1, further comprising a material storage tank. 4. The energy recovery device for a supercritical fluid thermal reaction plant according to claim 1, wherein the fuel is low-grade slurry-like coal. 5. A steam generator, comprising: a steam port for supplying steam to the steam turbine; a steam port for performing expansion work in the steam turbine to condense steam for driving the generator to supply water; 3. The energy recovery apparatus for a supercritical fluid thermal reaction plant according to claim 2, further comprising a neutralization solution port for receiving a neutralization solution from the condenser. 6. The energy for a supercritical fluid thermal reaction plant according to claim 1, wherein the energy recovery unit is a screw engine that converts the energy of the supercritical fluid from the supercritical fluid thermal reaction unit into power. Collection device. 7. The screw engine is classified into a high-pressure screw engine, a medium-pressure screw engine, and a low-pressure screw engine arranged in a cascade along the flow of the supercritical fluid.
An energy recovery apparatus for a supercritical fluid thermal reaction plant according to claim 1. 8. The energy recovery apparatus for a supercritical fluid thermal reaction plant according to claim 7, wherein in the high-pressure screw engine, a raw fuel transfer pump of a fuel supply unit is connected by an axial power transmission unit. 9. The energy recovery device for a supercritical fluid thermal reaction plant according to claim 7, wherein the medium pressure screw engine has a booster pump of a fuel supply unit connected by an axial power transmission unit. 10. The supercritical fluid thermal reaction plant according to claim 7, wherein the low-pressure screw engine has at least one of a compressor and a generator of an oxygen supply system connected by a shaft power transmission unit. Energy recovery device. 11. The high-pressure screw engine, the medium-pressure screw engine, and the low-pressure screw engine each have a pressure regulating valve for regulating the pressure of the supercritical fluid supplied from the supercritical fluid thermal reaction section at the inlet side. The energy recovery device for a supercritical fluid thermal reaction plant according to claim 7, characterized in that: 12. The supercritical fluid thermal reaction plant according to claim 1, wherein the condenser includes a heat exchange unit for condensing the supercritical fluid supplied from the energy recovery unit with a neutralizing solution. Collection device. 13. The energy recovery apparatus for a supercritical fluid thermal reaction plant according to claim 12, wherein the neutralizing solution is sodium hydroxide. 14. The energy recovery system for a supercritical fluid thermal reaction plant according to claim 1, wherein the condensed water returned from the condenser to the raw fuel storage tank of the fuel supply unit contains sodium sulfate.