KR20230015482A - By Pre-Condensate Oxyfuel Combustor Exhaust Gas Cooling, Heat Recovery and CO2 Capture Device and Its Heat Pump and Net Zero Operation Method of Gas Turbine Power Plant - Google Patents

Abstract

The present invention relates to heat pump components for oxy-fuel combustion, exhaust gas cooling, exhaust heat recovery, and CO2 capturing in a gas turbine, and a carbon neutral operation method. In the present invention, steam is condensed in a special heat exchanger, and the subsequent turbine exhaust gas is cooled and condensed by an exhaust heat absorber, so that the turbine exhaust gas is cooled and condensed. Since the turbine exhaust gas is condensed, high power production efficiency is realized, and also high power generation efficiency is achieved by turbine exhaust heat recovery. In addition, exhaust CO2 is captured by oxy-fuel combustion and dissolved in cooling water to produce carbonated water, and hydrogen is produced from the carbonated water, thereby realizing carbon (CO2) neutrality.

Description

Exhaust cooling by condensate and pure oxygen combustion, exhaust heat recovery and CO2 capture device, heat pump, and carbon neutral operation method {By Pre-Condensate Oxyfuel Combustor Exhaust Gas Cooling, Heat Recovery and CO2 Capture Device and Its Heat Pump and Net Zero Operation Method of Gas Turbine Power Plant}

The present invention relates to an apparatus for exhaust cooling, exhaust heat recovery and CO ₂ capture by gas-condensate and pure oxygen combustion, a heat pump and a carbon neutral operation method thereof, wherein oxygen and nitrogen produced from air are used as refrigerants, and a combustion chamber Only pure oxygen is injected, and CO ₂ as a working fluid is injected and recycled into the combustion chamber to realize pure oxygen combustion, and the turbine exhaust is cooled with already cooled pre-condensate and refrigerant oxygen, and steam is condensed , CO ₂ is captured, the entire amount of turbine exhaust heat is recovered, high power production efficiency is realized in the turbine due to the exhaust (steam) cooling multiple effect, and the captured CO ₂ is dissolved in the cooling water as carbonated water, and this carbonated water becomes hydrogen. Hydrogen is produced by being supplied to the production system, and nitrogen, which is used as hydrogen and refrigerant, is supplied to an ammonia production plant, which is an optimal medium as a means of storing hydrogen, and ammonia is produced so that carbon (CO ₂ ) neutrality is economically realized. It is characterized by its composition.

Nitrogen in the air is about 78%, oxygen 21%, and other (CO ₂ , argon, etc.) 1%. In a gas turbine, since fuel (NG) is injected together with air, it was not easy to capture carbon dioxide (CO ₂ ) due to nitrogen (78%) in the combustion chamber exhaust. In order to solve this problem, oxy-combustion has recently been studied. In other words, if only pure oxygen is injected into the combustion chamber instead of air, the combustion chamber exhaust (combustion gas) consists only of steam and CO ₂ , so the exhaust is cooled to recover steam and easily collect CO ₂ . This pure oxy-combustion became a new problem of overheating of the combustion chamber as the working fluid decreased as nitrogen was removed. In order to solve this problem, a new type of boiler is being developed that recirculates a large amount of exhaust exhaust already discharged from the combustion chamber to the combustion chamber. Meanwhile, in the present invention, reference was made to a 'nitrogen gas production system' invented and patented by POSCO (10-1481614, 2015.01.06.).

U.S. Clean Energy System is researching a CES cycle in which steam is recirculated as a working fluid to prevent overheating of the combustion chamber due to pure oxygen combustion in a gas turbine. On the other hand, according to 'Gas Turbine Engine Theory and Application' (Professor Hong Yong-sik, Inha University 1985.01.15.), aircraft gas turbines, (Pratt & Whitney) JT9D and (Rolls-Royce) Spey, Pegasus, etc. Using), water is sprayed and injected into the combustion chamber, and the injected steam is heated as superheated steam to increase thrust. In addition, in order to solve the problem of overheating of the combustion chamber due to pure oxy-combustion, research is underway in which CO ₂ is recycled to the combustion chamber in the Allam cycle. Circulating steam as the working fluid, (8H ₂ O + 2O ₂ + CH ₄ = 8H ₂ O + CO ₂ + 2H ₂ O), is recycled to the combustion chamber, or CO ₂ is (8CO ₂ + 2O ₂ + CH ₄ = 8CO ₂ + CO ₂ + 2H ₂ O), when recirculated to the combustion chamber, the problem of overheating of the combustion chamber and the decrease in power production efficiency in the turbine due to the reduction of working fluid are solved.

In a steam turbine, the turbine (steam) exhaust is cooled in the condenser and the steam is condensed. Due to this exhaust cooling effect, the turbine exhaust is exhausted from the turbine to the condenser at a back pressure of 0.2 bar, and thus the steam running from the turbine toward the blades. As is sucked into the condenser, the steam particles run at a higher speed and collide with the turbine blades, thereby exerting more impact (Δmv) on the blades according to the law of conservation of momentum. That is, high power production efficiency is realized in the turbine. However, the enormous exhaust heat of steam (539 kcal/kg heat of condensation at atmospheric pressure) is released to the sea as cooling water. In other words, a huge amount of heat equivalent to 50% of the total amount of heat added to the steam in the boiler (or steam generator) is released to the sea.

Carbon dioxide (CO ₂ ) freezes as dry ice when cooled below -78.5℃ at 5.1 atmospheres or higher, sublimates directly without going through a liquid at atmospheric pressure, and melts into liquid at (triple point) 5.1 atmospheres -56.58℃ or higher. In addition, it is known that gaseous CO2 dissolves relatively well in seawater and dissolves more readily when pressure is applied at a lower temperature. Hydrogen has a very low boiling point of -252.87℃, so commercial hydrogen is not produced as a liquid, but is usually compressed at high pressure and used. Ammonia (NH ₃ ), which is a colorless gas at room temperature and is mainly used as a raw material for fertilizer, has a boiling point of -33.34 ° C and is liquefied at a low pressure (8.6 bar) at room temperature (20 ° C). This NH ₃ has been conventionally produced at high temperature and high pressure (200 bar 450° C.), but recently (UNIST), a new technology for producing at 45° C. at 1 atm pressure has been developed at the Ulsan Institute of Science and Technology. Due to these characteristics, it has recently been actively studied as a medium for storing and transporting hydrogen. In other words, it is a technology that does not pollute the environment by using nitrogen, which is 78% of the air, to make and store NH ₃ , then extracts hydrogen from NH ₃ and releases nitrogen back into the atmosphere. In addition, 1.5 times more hydrogen is stored in NH ₃ than in liquid. Also recently, at the Korea Advanced Institute of Science and Technology (KIST), a hydrogen extractor has been developed that separates this hydrogen from nitrogen from NH ₃ at a temperature below 450 °C using a catalyst and a membrane device. That is, hydrogen is stored in a storage container (NH ₃ ) at a low pressure (8.6 bar) at 1.5 times the amount of liquid, and it shows the possibility of a future new technology that can easily take out and use the hydrogen from the storage container.

In the present invention, pure oxygen combustion is implemented so that carbon dioxide (CO ₂ ) can be easily captured, and circulating water as a working fluid is recycled to the combustion chamber to prevent overheating of the turbine combustion chamber. As in the steam turbine, the turbine (exhaust) steam is cooled and condensed to realize high power production efficiency in the turbine, and the turbine exhaust is exhausted with a back pressure of 0.2 bar, and its exhaust heat is recovered.

In addition, in the present invention, as in a steam turbine, the turbine (exhaust) steam must be cooled and condensed so that the turbine exhaust is exhausted with a back pressure of 0.2 bar, and its exhaust heat must be recovered so that high power production efficiency is realized in the turbine, as in a steam turbine.

In the present invention, oxygen and nitrogen produced by liquefying separation from air are used as refrigerants, only oxygen is injected into the combustion chamber, and circulating steam of nitrogen (78%) as a working fluid is used as a working fluid to prevent overheating of the combustion chamber, as follows, Exhaust heat is recovered and injected into the combustion chamber as superheated steam and recirculated to realize pure oxygen combustion. When circulating steam is recirculated to the combustion chamber as a working fluid, the turbine exhaust (8H2O + 2O ₂ + CH ₄ = 8H ₂ O + CO ₂ + 2H ₂ O) consists mostly of steam. This vapor has a characteristic of condensation heat that is greater than any other liquid (539 kcal/kg based on atmospheric pressure), and it is not easy to condensate with any refrigerant, but in the present invention, the turbine exhaust is condensed with this enormous (condensation heat) vaporization heat. Turbine (steam) exhaust is exhausted with a back pressure of 0.2 bar and 110°C (saturation temperature 60.06°C), condensed to 60°C, and already cooled and condensed 60°C, pre-exhaust, pre-condensate, as a refrigerant, it cools down

In the present invention, steam is condensed in a special heat exchanger (exhaust cooler) corresponding to a steam turbine condenser, and CO ₂ is cooled and collected at below zero (-13°C). A turbine exhaust heat absorber is installed in this exhaust cooler, and in this exhaust heat absorber, steam-condensate evaporates into 90°C steam as turbine exhaust heat at 110°C, and cools the subsequent turbine exhaust with evaporation heat. That is, (110 ° C - 90 ° C) a cooling heat amount of 9.2 kcal / kg or more corresponding to Δ20 ° C is further supplied, so that the turbine exhaust is cooled.

As the turbine exhaust is multiplied, the working fluid in the turbine is exhausted at a back pressure of 0.2 bar, as in a steam turbine, so that high power production efficiency is realized in the turbine, and also, as follows, turbine exhaust heat is recovered to achieve high power generation efficiency. Steam has an adiabatic coefficient k = 1.327 at 25°C and 1 atm. With this k value, when 0.2 bar 150°C steam is adiabatically compressed to 5 bar, the temperature of this 0.2 bar 150°C steam rises to 657°C. In the present invention, the steam-condensate steam, which absorbs turbine exhaust heat and is heated to 90 ° C, is heated to 150 ° C (Boost up) with nitrogen by means of a heat pump, pressurized at 5 bar, and further heated to 650 ° C after the temperature rises. By raising the temperature, this 650 ° C steam is cooled and condensed into refrigerant nitrogen as a heat transfer medium, and this nitrogen is heated to 630 ° C, and the enormous (latent heat) (plural) condensation heat of this steam is 630 °C is converted to a heating value. Thereafter, this condensate (which has been cooled and condensed) is preheated to 500° C. or higher with the heated heat of nitrogen as feed water, and the enormous turbine exhaust heat is recovered in its entirety.

In the condensate, 20 mol% steam generated by combustion is cooled with 5°C cooling water, exhaust CO ₂ is collected by pure oxy-combustion, dissolved in this cooling water as carbonated water, and with this carbonated water, the following recently developed technology This is utilized so that hydrogen is produced so that carbon (CO ₂ ) neutrality is realized.

CO ₂ constantly generated in the combustion chamber is captured at a low temperature below zero (-13°C) as a treatment method, dissolved in carbonated water in seawater as the cooling water and catalyst, and this carbonated water generates (recently developed) electricity and hydrogen. It is supplied to the production system and configured to produce clean energy hydrogen. Subsequently, ammonia (NH ₃ ) is produced from this produced hydrogen and nitrogen used as a refrigerant for exhaust cooling, and this hydrogen is 1.5 times more than liquid, at a low pressure (8.6 bar) at room temperature, in NH ₃ stored and configured so that CO ₂ neutrality is realized.

In the present invention, CO ₂ is not emitted into the atmosphere, nitrogen is utilized as a refrigerant, and with heat pump technology, gas turbine (steam) exhaust is multiplied and its exhaust heat is recovered, so that high power production efficiency is realized in the turbine, In addition, hydrogen is produced from CO ₂ produced by combustion, and ammonia (NH ₃ ) is produced from this hydrogen and nitrogen used as a refrigerant, and eventually, hydrogen is produced from the CO ₂ in question, which is 1.5 times less than liquid compared to ammonia. This is characterized in that it is configured so that CO ₂ neutrality is realized by being stored.

1 is a flow diagram showing a flow of a working fluid, showing a process in which a turbine exhaust, (pre-exhaust) is cooled into a plurality of pre-cooled condensate, and CO ₂ is captured in the present invention.
FIG. 2 is a diagram showing the structure of the exhaust cooler according to the present invention, wherein turbine exhaust is sucked and cooled by the exhaust cooler, steam is condensed, and CO ₂ is collected at a low temperature (-13° C.).
3 is a view showing the shape of a main part of a blade for collecting and discharging non-condensable gases lighter than CO ₂ , such as oxygen and CO, used in the present exhaust cooler.
4 is a flow diagram showing a process in which turbine exhaust heat is recovered as circulating working fluid CO ₂ .
5 is a flow diagram showing a flow of a working fluid of a nitrogen liquefaction cooling system showing a process in which nitrogen is cooled and liquefied.
6 is a temperature-pressure diagram showing physical characteristics of CO ₂ used as a circulating working fluid in the present invention.
7 is a view showing the main part of the CO ₂ supercritical fluid heat exchanger according to the present invention.
8 is a view symbolically showing the structure of CO ₂ supercritical fluid (ScCO ₂ PreHtr#1, #2, #3) CO ₂ preheaters #1, #2, and #3 heat exchangers according to the present invention.
9 is a view showing the shape of a main part of a diffuser nozzle in which CO ₂ supercritical fluid isothermally expands in the present invention.
10 is a TS diagram showing the power production process by cooling the turbine (via HRSG) exhaust, showing the power production process by citing the Brayton cycle in the gas turbine (HRSG) combined cycle to which the present invention is applied.
11 is a flow diagram showing the flow of working fluid in a combined cycle in which a conventional gas turbine is configured with a steam turbine as an HRSG.

In the present invention, as a circulating working fluid, CO ₂ is recycled to the combustion chamber to realize pure oxygen combustion, and CO ₂ is collected to realize carbon (CO ₂ ) neutrality. 1 is a flow diagram showing the working fluid flow, showing that gas turbine (via HRSG) exhaust is already cooled (pre)-plural, cooled and condensed, and CO ₂ is captured in the present invention. 2 is a diagram symbolically depicting the structure of this exhaust cooler, showing that the turbine exhaust is sucked (in the exhaust cooler) and cooled, steam is condensed, and CO ₂ is collected at a low temperature (-13 ° C). 3 is a view showing the shape of a blade for effectively cooling turbine exhaust (suction) introduced into the exhaust cooler and collecting and removing non-condensable gases such as CO, O ₂ , and N ₂ .

In the present invention, in order to prevent overheating of the turbine combustion chamber, CO ₂ as a circulating working fluid is recycled to the turbine combustion chamber to realize pure oxygen combustion, (8CO ₂ + 2O ₂ + CH ₄ = 8CO ₂ + CO ₂ + 2H ₂ O), the turbine exhaust is cooled to 110℃ (via HRSG), and, as in a steam turbine, back pressure is 0.2 bar, and (suction) inlet cooling is performed in this exhaust cooler, steam is condensed, and CO ₂ generated is emitted (collected) at -13 °C. Steam has a huge (atmospheric pressure standard 539 kcal / kg) condensation heat, so it is not easy to cool and condensate this steam, but in the present invention, this turbine exhaust is already cooled and condensed. In other words, as gas-condensate evaporates, the subsequent turbine exhaust becomes cooled condensate with enormous heat of vaporization (condensation heat). As shown in FIG. 2, this plural number is injected into the exhaust heat absorber tube at the inlet, and the turbine 110 ° C. 0.2 bar exhaust (suction) introduced into the present exhaust cooler is, in this exhaust heat absorber, (saturation temperature 60.06 ℃) is condensed at 60 ℃, and the saturation temperature is evaporated by turbine (110 ℃) exhaust heat, absorbs turbine exhaust heat, and rises to 90 ℃. That is, as follows, with a very small amount of cooling heat, the turbine exhaust is cooled, steam is condensed, and CO ₂ generated by combustion is captured and discharged at -13°C. The amount of heat by which this CO ₂ is cooled to -13℃ plus the amount of heat corresponding to the temperature difference (Δ20℃) between the turbine exhaust temperature and the temperature difference (Δ20℃) between steam and condensate steam (110℃ - 90℃) are supplied As shown in FIG. 2, a small amount (13 mol%) of liquid refrigerant nitrogen is supplied to the steam cooler, and (20 mol% x 130%) refrigerant oxygen is supplied to the vapor cooler. The cooling process of this turbine exhaust and the process by which CO ₂ is discharged (captured) at -13 °C is described in detail below. As a result of the multiple cooling effect of the exhaust, the turbine exhaust is sucked into the exhaust cooler at a back pressure of 0.2 bar, and power is produced with high efficiency in the turbine, as in a steam turbine.

Of the CO ₂ (80 mol% + 10 mol%) discharged (collected) at -13°C in this exhaust cooler, circulating CO ₂ 80 mol% CO ₂ is pressurized at 20 bar and heated to 360°C or higher. This 20bar 80mol% CO ₂ (CO ₂ Condenser) is pumped to the CO ₂ condenser, cooled to -20℃ liquid phase with 112mol% nitrogen liquid refrigerant, and pressurized above the critical pressure (73bar), and this refrigerant nitrogen is 340℃ is heated with That is, CO ₂ is cooled and liquefied, and the heat of 360°C of CO ₂ is converted into the heat of heating of nitrogen at 340°C. Thereafter, with the increased temperature of nitrogen, -20°C CO ₂ as described above is generated as a supercritical fluid, and the entire amount of turbine exhaust heat is recovered.

4 is a flow diagram showing a process in which turbine exhaust heat is recovered as a working fluid CO ₂ . 5 , in the supercritical fluid (ScCO ₂ PreHtr#3) CO ₂ preheater #3 of the nitrogen liquefaction cooling system, ₁₆ mol% CO ₂ out of 80 mol of CO 2 is produced as a supercritical fluid and preheated to 620°C. The 340°C nitrogen is pumped to the steam (StmHtr) heater and the supercritical fluid (ScCO ₂ PreHtr#2) CO ₂ preheater #2 of the turbine exhaust heat recovery system (FIG. 4), and the -20°C (80-16) 64 mol% CO ₂ is pumped to supercritical fluid (ScCO ₂ PreHtr#1) CO ₂ preheater #1 and supercritical fluid CO ₂ preheater #2, and (FIG. 1) cools the turbine exhaust in the exhaust heat absorber of the exhaust cooler, The steam heated to 90°C is pumped to the steam heater, and all of the turbine exhaust heat is recovered as follows. 25 mol% nitrogen of the 112 mol% nitrogen is heated to 325 ℃ 90 ℃ 0.2 bar steam, cooled to 110 ℃, 0.2 bar 325 ℃ steam compressed to 1 atm, heated to 610 ℃, supercritical fluid (ScCO ₂ PreHtr#1) It is pumped to preheater #1. In this ScCO ₂ PreHtr#1, 32 mol% CO ₂ out of the 80 mol% -20°C CO ₂ is produced as a 610°C steam as a supercritical fluid, preheated to 595°C, and the 610°C vapor is cooled to 5°C. will be plural As shown in FIG. 1, CO ₂ generated by 20 mol% combustion at 5°C is pumped to a mixer where carbonated water is dissolved in cooling water. (80-32-16) 32 mol% CO ₂ in the -20°C CO ₂ is from (Supercritical Fluid CO ₂ Preheater #2) ScCO ₂ PreHtr#2. The 340 ° C (112 - 25) 87 mo% nitrogen is produced as a supercritical fluid, preheated to 320 ° C, and the nitrogen is cooled to -5 ° C. The remaining 16 mol% -20°C CO ₂ of -20°C CO ₂ (FIG. 5) is produced as a supercritical fluid in ScCO ₂ PreHtr#3, 30 bar 650°C nitrogen, and preheated to 620°C. These 620°C 16 mol% ScCO ₂ , 595°C 32 mol% ScCO ₂ , and 320°C 32 mol% ScCO ₂ , preheated with a supercritical fluid, are mixed to 492° C., as shown in FIG. 1 ( FIG. 9 ) diffuser It is injected into the combustion chamber as CO ₂ gas through a nozzle.

Russian (Kapitza) Kapitza, who received the 1978 Nobel Prize in Physics in the field of cryogenic physics, liquefies air. In the air liquefaction method developed by Claude, France, a piston pump type compressed air expander is an inverse turbine type The air liquefaction efficiency was greatly improved by replacing the expander with the expander, and this air liquefaction method is still widely used today. In the present invention, by utilizing this air-liquefaction method, after nitrogen already used as a refrigerant is stored, it is cooled and liquefied again, and is used as a heat pump means and as a heat transfer medium for recovering turbine exhaust heat. In the present invention, 130% more oxygen is supplied to the combustion chamber than the theoretical supply amount, and 130% more nitrogen is also produced and used as a refrigerant. In this liquid refrigerant (80mol% x 130%) 104mol% nitrogen, 112mol% nitrogen used to cool the -13℃ CO ₂ to -20℃ liquid phase, 13mol% nitrogen for cooling compressed air for oxygen and nitrogen production, (FIG. 2) In this exhaust cooler, since 7 mol% nitrogen used for cooling the turbine exhaust and 5 mol% nitrogen required to cool the generated 10 mol% CO2 at -50 ° C, the total liquid phase ((112 - 104 + 13 + 7 + 5) 33 mol% nitrogen is cooled to the liquid phase as below, and the refrigerant nitrogen is supplied.

Figure 5 is a flow diagram showing the flow of the working fluid of the nitrogen liquefaction cooling system, showing the process of cooling and liquefying nitrogen used as a refrigerant to use it as a refrigerant again. As shown, 1 atm nitrogen is compressed to 30 bar with a compressor, the temperature is raised to 650 ° C, and this compressed nitrogen is originally cooled in a secondary (2nd N2 Cooler) cooler in the cooling system of this copy car, but in the present invention , in the supercritical fluid (ScCO ₂ PreHtr#3) preheater #3, the previously described 16 mol% circulating water is preheated to 620° C., and 1 atm (33+1) 34 mol% nitrogen is cooled to -5° C., and the nitrogen While reducing the compressor load, this nitrogen is then efficiently cooled and liquefied, and of this nitrogen cooled to -5 ° C, 1 mol% nitrogen is adiabatically expanded to 1 atm through an expansion valve so that it does not further cool and liquefy in the secondary cooler, After cooling to -170°C, this secondary cooler is bypassed and stored in a low-temperature nitrogen storage tank. In addition, the flow rate of the previous 1 atm low-temperature nitrogen recirculated to this compressor is controlled, as shown, so that the 1 atm nitrogen is not compressed below a set temperature (650° C.) in the compressor, so that the nitrogen in the high-temperature nitrogen storage tank and 80° C. is mixed into the compressor and the rest is stored in a low-temperature nitrogen storage tank. Cooled to -5°C in the primary cooler, this compressed nitrogen is further cooled with (preceding) 1atm (expansion) low-temperature nitrogen in the secondary cooler, and then 80% of this cooling nitrogen flows (Kapizza's reverse turbine expander). The temperature of this nitrogen is greatly reduced by the gradual adiabatic expansion by this rotary vacuum pump. With this 1 atm low-temperature 80% nitrogen, the remaining 20% nitrogen is cooled and liquefied as it flows from the nitrogen (N ₂ Condenser) condenser to the tube. This liquid nitrogen moves to the liquid nitrogen (Lip.N ₂ Cooler) cooler, flows through the tube, and is further cooled. According to the Joule-Thomson effect, the temperature of this nitrogen (saturation temperature -195.79 ° C) decreases to -196 ° C. Thus, some of this nitrogen is liquefied at 1 atm -196 °C, and the rest is vaporized. This gaseous nitrogen, whose temperature has dropped significantly, cools the subsequent 30 bar liquid nitrogen flowing into the tube in the (Liq.N ₂ Cooler) liquid nitrogen cooler, and is mixed with nitrogen discharged from the nitrogen condenser, and this mixed nitrogen enters the secondary cooler, cools the subsequent 30 bar -5 ° C nitrogen, is sucked into the vacuum pump, and is re-entered into the compressor. Nitrogen liquefied at 1 atm in this evaporator vessel is supplied to the outlet pipe of the liquid nitrogen supply pump (FIG. 1). The reason why the 1 mol% nitrogen bypassed the secondary cooler is as follows. In normal operation, only 33 mol% nitrogen needs to be cooled to the liquid phase, but in order to preheat the (supercritical fluid) ScCO ₂ to 620° C., 34 mol% nitrogen must be compressed by a compressor, so that 1 mol% nitrogen is not cooled to the liquid phase. As a means, the secondary cooler is bypassed. In effect, this bypass device is utilized as a means of preheating the circulating water to a predetermined temperature.

In the nitrogen liquefaction cooling system described above (FIG. 5), 1 atm nitrogen is compressed to a pressure lower than 30 bar in the realization stage of the present invention. Through trial and error, this economical nitrogen compression pressure is set so that this nitrogen is compressed to a pressure as low as possible and liquefied into a liquid phase while reducing the drive power of this compressor. As shown in FIG. 4, 110°C 25 mol% nitrogen is returned to the nitrogen storage tank, (FIG. 1) 50°C 7 mol% nitrogen and an external (CO ₂ ExCooler) CO ₂ cooler cool the exhaust in this exhaust cooler, 80 Since 5 mol% of ℃ nitrogen is returned to the nitrogen storage tank, after storing this nitrogen in a high-temperature storage tank, when the nitrogen is compressed to 27 bar, the temperature is raised to 650 ℃ or more. For this reason, in the present invention, (preceding) the low-temperature nitrogen expanded to 1 atm is directly re-entered into the compressor, so that the compressed nitrogen temperature does not fall below 650 ° C., as shown in the figure, in a separate low-temperature storage tank. , configured to be stored.

The vacuum pump shown in FIG. 2 and the rotary piston vacuum pump shown in FIG. 5 installed under the CO2 cooler in this exhaust cooler have not been commercialized yet, but have been patented (10-24115730000, 2022-06-16) ' It is a 'rotary piston gas transfer (suction/compression) pump', and in a donut-shaped annular cylinder, the piston rotates in close contact with the cylinder, and a disk blocks the piston, but this piston and disk are (watches, instruments, etc.) Based on the pin gear cycloid curve (used for teeth), it is composed of a helical gear (with only one tooth) so that they rotate without colliding with each other, so that the piston rotates Continuously, it is realized that the working fluid is sucked in behind the piston and compressed and discharged in front of the piston. These rotary piston vacuum pumps suck (like a piston pump, but continuously like a centrifugal pump) a working fluid, compress it, and release it.

In a recently developed gas turbine, the compression ratio of compressed air compressed by a turbine shaft series compressor is usually as high as 1/30 or more, and the temperature of this compressed air is as high as 700°C or more. In the present invention, the pressure and temperature of this compressed air, as shown in FIG. 1, were arbitrarily set to 30 bar and 450 ° C. In the process of realizing the present invention, it is reset to an economically appropriate value according to the size of the gas turbine. This high-temperature compressed air, as follows, in the oxygen (Oxygen PreHtr) preheater, (Fig. 2) the oxygen preheated to 50 ° C in the exhaust cooler is preheated to 430 ° C with this compressed air and injected into the combustion chamber, and the compressed air is cooled to 350 ° C, as shown in the figure, to the compressed air cooler for oxygen and nitrogen production, adiabatically expanded at 5.5 kg / cm ² through an expansion valve, cooled to 110 ° C, and then supplied as pre-compressed air. In the present invention, 10 mol% CO ₂ of (8CO ₂ + 2O ₂ + CH ₄ = 8CO ₂ + CO ₂ + 2H ₂ O), generated by combustion, is collected at -13°C, dissolved in cooling water as carbonated water, and With carbonated water, hydrogen is produced in a system that produces hydrogen. As shown in FIG. 1, in this exhaust cooler, CO ₂ discharged at 0.2 bar -13 ° C is pressurized at 1 atm with a vacuum pump and heated to 100 ° C. This 1atm 100°C CO ₂ is cooled to -50°C with a small amount of liquid refrigerant nitrogen (5 mol%) in an external (CO ₂ ExCooler) CO ₂ cooler so that it can be easily dissolved in the cooling water, and the nitrogen is cooled to 80°C is heated with In addition, in the compressed air cooler for producing oxygen and nitrogen, 13 mol% liquid refrigerant nitrogen cools compressed air at 120 ° C to 77 ° C, raises the temperature to 60 ° C, and stores it in a nitrogen storage tank.

The pre-compressed air (110 ° C) is mixed with a small amount of 210 ° C compressed air compressed by the auxiliary compressor at (estimated) 120 ° C, recirculated to the compressed air cooler, cooled with liquid refrigerant (13 mol%) nitrogen, and cooled Compressed air that meets the operating conditions (5.5kg/cm ² 77℃) is supplied to the distillation column where oxygen and nitrogen are separated and produced (Distillation Column), and the nitrogen is cooled to 60℃ and stored in a nitrogen storage tank. The above cooling operating conditions refer to the 'nitrogen gas production system' invented and patented by POSCO. In this oxygen and nitrogen production process, after the compressed air production process, oxygen and nitrogen are produced through many processes. Oxygen and nitrogen production technologies are developing day by day with industrial development, and as shown, these production technologies, briefly described as distillation towers, do not fall within the scope of the present claims.

As described above, the -13℃ CO ₂ discharged from the exhaust cooler is further cooled to -50℃ so that it dissolves well in water, and the mixture of cooling water (5℃) generated by combustion and seawater (Mixer ) is dissolved into carbonated water in a mixer, and this carbonated water (recently developed technology) is supplied to a system that produces hydrogen as CO ₂ to produce hydrogen, and this produced hydrogen and nitrogen used as a refrigerant are supplied to an ammonia production plant , Ammonia (NH ₃ ), which is an optimal medium for storing hydrogen, is produced, and clean energy hydrogen, 1.5 times more than liquid, is stored in NH ₃ at low pressure (8.6 bar) at room temperature, resulting in carbon (CO ₂ ) Neutrality is realized.

The following describes a process in which the turbine exhaust is cooled and the exhaust heat thereof is recovered from a thermodynamic point of view in the present invention. In the present invention, CO2 as a working fluid is injected and recirculated into the combustion chamber (8CO ₂ + 2O ₂ + CH ₄ = 8CO ₂ + CO ₂ + 2H ₂ O), and pure oxygen combustion is implemented. Oxygen supplied to the combustion chamber is produced in liquid form, 130% more than the theoretical supply, and nitrogen is also produced (80mol% x 130%) by 104mol%. Turbine exhaust (via HRSG) enters (suction) into this exhaust cooler at a back pressure of 0.2 bar and 110 ° C, steam is cooled and condensed, and exhaust (10 mol%) CO ₂ is discharged (collected) at -13 ° C, leading ( Pre-condensate, in the exhaust heat absorber, evaporates into 90 ℃ steam and absorbs exhaust heat, the refrigerant (20 mol% x 130%) oxygen is preheated to 50 ℃ (temperature raised), and the refrigerant (7 mol%) ) Nitrogen is heated to 50℃, and the amount of heat to be cooled and the amount of heat to be cooled (Heat Balance) form a thermal equilibrium. In more detail, in this exhaust cooler, the cooling heat of (110℃-90℃) Δ20℃ (20mol%) steam and the cooling heat of 10mol% CO ₂ cooling from 110℃ to -13℃ are the sum of the cooling heat The amount of heat for preheating this liquid (20 mol% x 130%) oxygen from -183℃ to 50℃ and the amount of heat for heating liquid (13 mol%) nitrogen to 50℃ and cooling the turbine exhaust form thermal equilibrium. When this turbine exhaust is cooled by the usual cooling water method, a huge amount of condensation heat of steam (563 kcal/kg) must be supplied, but this condensation heat is absorbed as the amount of evaporation heat while the gas and condensate steam evaporates, Even if only the amount of heat (9 cal/kg) corresponding to the temperature difference (Δ20°C) is further supplied as cooling heat, the turbine exhaust is cooled and condensed. This -13℃ 10mol% CO ₂ is pressurized to 1atm with a vacuum pump, and after raising the temperature to 100℃, it is cooled to -50℃ with liquid (5mol%) nitrogen in an external CO ₂ cooler, and this nitrogen achieves thermal equilibrium. The temperature is raised to 80 ° C. In a compressed air cooler for producing oxygen and nitrogen, liquid refrigerant -196℃ nitrogen cools 130 mol% 120℃ compressed air to 77℃ and heats it up to 60℃ to achieve thermal equilibrium. Oxygen preheated to 50°C in this exhaust cooler is preheated to 430°C with 450°C compressed air compressed by a series compressor on the turbine axis, and this 450°C compressed air is cooled to 350°C and 5.5kg/kcm through an expansion valve. After adiabatic expansion at ² , it is cooled to 110°C and supplied as pre-compressed air to the compressed air cooler.

In the turbine exhaust heat recovery system shown in FIG. 4, the gas-condensate (20 mol%) steam, which evaporates at 90 ° C. in the exhaust cooler and absorbs enormous exhaust heat, is 340 ° C. (25 mol%) in the steam (StmHtr) heater described above. ) is heated to 325 ° C with nitrogen, and the nitrogen is cooled to 110 ° C to achieve thermal equilibrium. This 0.2bar 325℃ steam is pressurized at 1atm and heated to 610℃, and then, in the supercritical fluid (ScCO ₂ PreHtr#1) preheater #1, 32mol% CO ₂ above the critical pressure (73bar) of -20℃ described above is heated to 595℃. After preheating with a supercritical fluid, this 20 mol% 610°C steam is condensed with 5°C cooling water to achieve thermal equilibrium. Next, in (supercritical fluid) ScCO ₂ preheater #2, 32mol% -20°C CO ₂ is preheated to 320°C supercritical fluid with the remaining (112mol%-25mol%) 87mol% 340°C nitrogen, which nitrogen is -5 It cools down to °C and achieves thermal equilibrium. Of this -20℃ CO ₂ , the remaining (80mol%-32-32) 16mol% -20℃ CO ₂ is, (FIG. 5) in ScCO ₂ PreHtr#3 of the nitrogen liquefaction cooling system, 30 bar 650℃ (33mol% + 1mol% ) Nitrogen is preheated to 620℃ as a supercritical fluid, and the nitrogen is cooled to -5℃ to achieve thermal equilibrium. As shown in FIG. 1, the 620 ° C supercritical fluid ScCO ₂ , 595 ° C ScCO ₂ and 320 ° C ScCO ₂ are mixed at 492 ° C, reduced to the operating pressure of the combustion chamber through a diffuser, and injected into the combustion chamber as CO ₂ gas is recycled

The following is a description comparing and organizing the driving power of a compressor that compresses turbine exhaust and refrigerant nitrogen with a heat pump means and the amount of heat recovered in order to recover turbine exhaust heat. When pressure is applied to a gas in a cylinder, (enthalpy) enthalpy (PV) increases, and when the piston moves backward, this enthalpy decreases, and the enthalpy decrease is converted into mechanical power. More specifically, when a gas is compressed with a piston, the temperature of the gas rises as the enthalpy due to the increase in PV increases, so the internal energy (U) of the gas also increases. That is, the enthalpy of a gas is given by H = PV + U. Therefore, the power applied to this gas is given by Δh = h2 - h1, the enthalpy difference before (h1) and after (h2) compression. Since CO ₂ discharged at 0.2 bar -13 °C from the turbine exhaust cooler is pressurized at 20 bar 360 °C, CO ₂ 0.2 bar -13 °C h1 = 362.21 kL/kg and CO ₂ 20 bar 360 °C h2 = 719.22 kJ/kg. Therefore, Δh = 357.01 kJ/kg. Applying the CO2 flow rate here, Pwr = 357.01 x 44 x 80 mol% = 12,567 kJ power is required. Since the steam-condensate steam is heated to 325℃ in a steam (StmHtr) heater and compressed to 1atm 610℃, steam 0.2bar 325℃ h1 = 3,126.75 kJ/kg before compression, 1atm 610℃ h2 = 3,727.7 kJ/kg after compression, Δh = 600.95 kJ/kg. Applying a compression flow rate, Pwr = 600.95 x 18 x 20 mol% = 2,163 kJ power is required. Next, (FIG. 5) in the nitrogen liquefaction cooling system, since 1 atm 80 ° C steam is compressed to 30 bar 650 ° C, nitrogen 1 atm 80 ° C h1 = 366.37 kJ / kg, nitrogen 30 bar 650 ° C h2 = 988.41 kJ / kg, Δh = 622.04 kJ .kg, and Pwr = 622.04 x 28 x (33 mol% + 1 mol%) = 5,922 kJ power is required. Therefore, the total power driving the compressor is (12,567 + 2,163 + 5,922) 20,652 kJ.

On the other hand, in the present invention, the entire amount of turbine exhaust heat is recovered by means of a heat pump. (FIG. 4) In the turbine exhaust heat recovery system supercritical fluid ScCO ₂ PreHtr#1, 32 mol% CO ₂ of 80 mol% CO ₂ at -20 ° C critical pressure (73 bar) or higher is preheated as a supercritical fluid at 595 ° C, CO ₂ 73 bar - 20°C h1 = 40.69 kJ/kg, CO ₂ 73 bar 595°C h2 = 986.92 kJ/kg, Δh = 946.23 kJ/kg, RcvH1 = 946.23 x 44 x 32 mol% = 13,323 kJ heat is recovered. Also, in ScCO ₂ PreHtr#2, since this -20°C 32 mol% CO ₂ is preheated to 320°C, h1 = 40.69 kJ/kg, 320°C h2 = 663.89 kJ/kg, Δh = 623.20 kJ/kg, RcvH2 = 623.20 x 44 x 32 mol% = 8,775 kJ heat is recovered. Next, in (FIG. 5) (supercritical fluid) ScCO ₂ PreHtr#3, as this -20°C 16 mol% CO ₂ is preheated to 620°C, h1 = 40.69 kJ/kg, CO ₂ 73 bar 620°C h2 = 1017.17= 1017.17 kJ/kg, Δh = 976.48, RcvH3 = 976.48 x 44 x 16 mol% = 6,874 kJ heat is recovered. Therefore, the total recovered heat is calculated as (13,323 + 8,775 + 6,874) 28,972 kJ.

The total amount of heat recovered (28,972 kJ) described above is more than 140% (28,972 / 20,652) of the compressor drive (20,652 kJ) power, and more than 40% of the heat is recovered compared to the driving power. If the compressor driving power is subtracted from this recovered heat amount, (Net) net (28,972 - 20,652) 8,320 kJ heat is recovered. This recovers 66% (Net) of 12,593 kJ of total exhaust heat (8,835 + 3,758) of 20 mol% steam produced by combustion and circulating CO ₂ exhausted (counted as heat loss). The reason why such a large amount of heat is recovered by means of a heat pump is that steam has a property of an enormous (latent heat) heat of vaporization. For example, CO ₂ has a heat of evaporation (240.89 kJ/kg) of 58 kcal/kg at 20 bar -20°C, and steam has a heat of evaporation of 539 kcal/kg at atmospheric pressure. If steam did not have the characteristic of enormous heat of vaporization like this CO ₂ , in the present invention, by means of a heat pump, exhaust heat is not recovered. That is, it is because the obtained power is not greater than the compressor driving power. In the present invention, the turbine steam is cooled and condensed by the enormous evaporation heat of the steam, and the entire turbine exhaust heat is recovered with this evaporation heat.

7 is a pressure-temperature diagram showing physical properties of CO ₂ used as a circulating working fluid. Normally, gaseous CO ₂ is pressurized above the critical pressure and produced as a supercritical fluid with high heat exchange efficiency. , this CO ₂ is preheated to a critical temperature (31°C) or higher to produce a supercritical fluid, and is preheated to a higher temperature with high heat exchange efficiency to recover turbine exhaust heat. (FIG. 3) In this exhaust cooler, CO ₂ discharged (collected) at -13 ° C is pressurized at 20 bar, heated to 360 ° C, as shown in FIG. 2, (CO ₂ Condenser) to CO ₂ condenser It is pressurized and liquefied (heat transfer medium, intermediate) by liquid nitrogen at -20°C. Next, this CO ₂ is pressurized above the critical pressure (73 bar) (with the pump NPSH maintained) and is generated as a supercritical fluid to recover turbine exhaust heat. This supercritical fluid CO ₂ is reduced to the operating pressure of the combustion chamber through the diffuser and injected into the combustion chamber as gaseous CO ₂ . The reason for this is as follows. When this CO ₂ supercritical fluid, above the critical pressure (73 bar), expands in a turbine to reach the critical pressure, the turbine blades rotating at high speed, in either design, the vapor and CO ₂ gas, or the CO ₂ gas particles and the density of the liquid Because supercritical fluid particles that are about half as large as are mixed and coexist, in addition, since this CO ₂ has a molecular weight of 44 and a mass more than twice that of steam (18), the turbine rotor (for linear motion mass Corresponding Rotational Inertia) Since the rotational inertia is not maintained constant, it cannot rotate at high speed. Therefore, in the present invention, CO ₂ gas is injected into the combustion chamber.

In general, the CO ₂ supercritical fluid heat exchanger is mainly used as a printed board type with high heat exchange efficiency. This printed board type heat exchanger is characterized in that the width of the passage is small and long with a width of several mm. This heat exchanger has high heat exchange efficiency, but when the counter fluid is cooled, the volume is reduced in one dimension instead of three dimensions, so in the present invention, a special heat exchanger is used because it is not suitable as a heat exchanger for CO ₂ supercritical fluid. For example, in the supercritical fluid (ScCO ₂ PreHtr#1) preheater #1 shown in FIG. 4, the 610°C steam of the shell is cooled by -20°C CO ₂ flowing into the tube, and its volume rapidly decreases, In this case, the compressor load compressing this vapor must be greatly reduced. 7 is a view showing the main part of the CO ₂ supercritical fluid heat exchanger of the present invention, and FIG. 8 is a view symbolically showing the structure of the supercritical fluid ScCO2 heat exchanger. In this heat exchanger, the tube diameters are all as small as several mm, like the flow path of a printed board type heat exchanger, and the tubes made of, for example, (ASME) Alloy 617 are formed in the shape of a coil spring, as shown in FIG. So, while the opposing fluid flows in the shell space, it frequently collides with the coil spring-shaped tube and is arranged at (for example) 45° in the shell so that the area for heat exchange is large. Therefore, while flowing in the shell, this opposing fluid frequently collides with the tube to achieve heat exchange, and its volume is rapidly reduced in three dimensions. Thus, the counterfluid compressor load is greatly reduced.

9 is a view showing the shape of a main part of a diffuser nozzle in which CO ₂ supercritical fluid isothermally expands. No matter how much pressure is applied to any pressure container with a general nozzle, the nozzle does not eject gas faster than the speed of sound. According to this principle, in supersonic aircraft, turbine combustion gases are ejected through this diffuser nozzle. When there is gas in a certain (container) cylinder and the piston slowly expands backwards, the temperature of this gas drops, and the corresponding energy is converted into mechanical power. However, if this piston moves backwards in an instant, the temperature of the gas in this cylinder does not drop and power is not produced. Even if the gas expands under reduced pressure through the diffuser, as shown in the figure, the vector velocity increases, but the average scalar velocity of the gas particles does not change, so the temperature does not decrease and there is no energy loss. Meanwhile, a direct-fired CO ₂ gas turbine-only combustor for pure oxygen combustion has not yet been commercialized. Recently, at the Korea Institute of Energy Research, a prototype of 42.8 bar has been achieved, and in the alarm (Allam) cycle patent, the minimum operating pressure of the CO ₂ supercritical fluid pure oxygen combustor is specified as 10 MPa or more, so this alarm cycle patent is avoided. To do this, the circulating working fluid CO ₂ supercritical fluid must be injected into the combustion chamber at a pressure of at least 10 MPa or less. Recently, in steam turbines, steam is operated at ultra-supercritical pressure. However, if CO ₂ supercritical fluid, which has a mass more than twice that of vapor, expands below the critical pressure at the critical point pressure, this CO ₂ Since gas particles and supercritical fluid particles (about 1/2 the density of the liquid phase) coexist, in addition, as an ideal gas produced by combustion and mixed with steam, the turbine rotor rotates at a very high speed. In this case, the rotational inertia (corresponding to the mass of the object moving in a straight line) is not kept constant, so that ultra-high speed rotational motion cannot be performed. In the present invention, for this reason, after the CO ₂ supercritical fluid is preheated and before being injected into the combustion chamber, after depressurization isothermal expansion to the combustion chamber operating pressure through a diffuser, It is injected into the combustion chamber as a gas and is sufficiently expanded with a back pressure of 0.2 in the turbine to produce power. That is, even before a direct fire oxy-combustor is developed and commercialized, a CO 2 gas turbine in which oxy-combustion is realized with this CO ₂ supercritical fluid can be realized.

10 is a TS showing the process of generating power in the present invention by citing the Brayton cycle, and FIG. 11 is a flow diagram showing the flow of working fluid in a system composed of a steam turbine and a combined cycle in which a conventional gas turbine is an HRSG. In a gas turbine, in the Brayton cycle, power is produced in a '1-2-3-4' cycle process, and the turbine exhaust is exhausted to the atmosphere at about 600°C. As shown in the figure, when this gas turbine is composed of a steam turbine and a combined cycle in the HRSG, the turbine exhaust is exhausted at 110° C. in the HRSG. That is, power corresponding to the area '1h-1-4-4h' corresponding to the temperature difference of the exhaust is further produced in the steam turbine. In a steam turbine, in a Rankine cycle, steam produces power in the turbine and is sucked into the condenser at a back pressure of 0.2 bar to cool and condensate. In the present invention, turbine (via HRSG) exhaust is sucked into the present exhaust cooler at a back pressure of 0.2 bar and 110°C, cooled, steam is condensed, and exhaust CO ₂ is discharged at -13°C. More specifically, in the combined cycle, the exhaust of the HRSG is open to the atmosphere, but in the present invention, since the exhaust of the HRSG is closed with the present exhaust cooler, the power combines the Brayton cycle and the Rankine cycle, (shown) In the 'exhaust cooling cycle', the working fluid is circulated in '1c-2-3-4c', and more power is produced in the turbine. In the present invention, CO ₂ supercritical fluid is isothermally expanded under reduced pressure through a diffuser, and then injected into a turbine. Therefore, unlike the Brayton cycle, the working fluid circulates in the process of '1c-2-3d_-3d+-4cd', and power is produced. In this TS diagram, the area circulating in '3d_-3-3d+' above and the area circulating in '4c-3d+-3d-4cd' below are the same. That is, the circulation area to '3d_-3-3d+' reduced by decompression isothermal expansion through the diffuser and the circulation area to '4c-3d+-3d-4cd' that are further revealed should be thermodynamically equal.

In the 'exhaust cooling cycle' described above, the power produced by the working fluid corresponding to the area of '1c-1h-4h-4c' is the working fluid particles running toward the blades in the turbine at a back pressure of 0.2 bar (Fig. 2) As it is sucked into this exhaust cooler, it runs faster and more impact (Δmv) is applied to the blades, and the power produced and turbine exhaust heat (ScCO ₂ ) are the (caloric) power recovered as supercritical fluid. In other words, in this 'exhaust cooling' cycle, which is not an open cycle like the Brayton cycle but a closed cycle like the Rankine cycle, the turbine exhaust heat is recovered, so the area of '1c-1h-4h-4c' More power is produced by the turbine.

To achieve carbon neutrality, the CO ₂ produced by combustion in gas turbines must be captured and not released into the atmosphere. If oxy-combustion is implemented, this CO ₂ can be easily captured. Therefore, for this pure oxy-combustion, a study is underway in which steam is recirculated into the combustion chamber in a CES (Clean Energy System) cycle, and a study in which CO ₂ supercritical fluid is recirculated into the combustion chamber in an Allam cycle is in progress. In this pure oxy-combustion, a new problem, which must be solved, arises in that the working fluid equivalent to nitrogen in the air is reduced, resulting in overheating of the combustion chamber and reduction in power output from the turbine. In the present invention, CO ₂ is recycled to the combustion chamber (8CO ₂ + 2O ₂ + CH ₄ = 8CO ₂ + CO ₂ + 2H ₂ O) to solve this problem. This 80 mol% CO ₂ is reset to an economical value in the process of realizing the present invention. As described above, this CO ₂ is preheated and injected as an ideal gas into the combustion chamber and recycled. Therefore, in the present invention, in the combustion chamber, the pure oxy-combustion environment is not significantly different from the conventional air combustion environment, and the problem of overheating of the combustion chamber due to pure oxy-combustion is solved. In conventional air combustion, it is impossible to liquefy nitrogen from turbine exhaust, and as in a steam turbine, (nitrogen) exhaust from the turbine cannot be exhausted with a back pressure of 0.2 bar, so power cannot be produced with high power production efficiency in the turbine, In the present invention, turbine (steam) exhaust is condensed, CO ₂ is cooled and liquefied, power is produced with high efficiency in the turbine, and all of the turbine exhaust heat is recovered by means of a heat pump, so that high power generation efficiency is realized in the turbine. do.

Below, with respect to this exhaust cooler shown in FIG. 2, a detailed description of the specific structure and the process of cooling the turbine exhaust is described. This exhaust cooler is an air fin cooler type, shell & tube type heat exchanger. At the inlet of this exhaust cooler, where the turbine exhaust is sucked in, an exhaust heat absorber that cools the turbine exhaust and absorbs its exhaust heat is installed, followed by an exhaust mini cooler. In the ceiling, a number of cold air circulation pipes are installed, and then, a number of water spray nozzles are installed to spray water vapor, and the inflow exhaust is cooled with liquid refrigerant nitrogen under the water spray nozzles. Next, a vapor cooler in which refrigerant oxygen flows into the tube and exhaust is cooled is installed, and liquid refrigerant oxygen is supplied to the tube on the far right. (CO ₂ Cooler) The CO ₂ cooler is installed higher than this steam cooler.

In the present invention, 130% more oxygen is supplied to the combustion chamber than the theoretical supply amount. Therefore, (20 mol% x (130%-100%) = 6 mol%) traces of oxygen, carbon monoxide (CO) generated by incomplete combustion, and non-condensable gases such as ultra-trace nitrogen, which are further supplied to the combustion chamber, as shown, As it is collected and removed, the inlet turbine exhaust is also cooled somewhat by its cooling heat through the exhaust minicooler. Next to the exhaust mini cooler, there are a plurality of cold air circulation pipes in which cold gases are sucked in from the ceiling of the CO2 cooler chamber and blown out from the ceiling behind the exhaust mini cooler. Non-condensable gases such as oxygen, CO, N ₂ and CO 2 are inhaled and circulated. At the T-junction above the inlet of the cold air circulation pipe (FIG. 3), a blower-type cold air circulation (Blade) blade is installed, and a collection space is formed above the T-junction where light non-condensable gas is collected, This collection space is equipped with a sensor that detects this non-condensable gas.

When the cold air circulation blade rotates, non-condensable gas and CO ₂ are sucked in, and heavy (large mass) CO ₂ flows by centrifugal force to the circulation pipe on the outer side of the circumference of the blade, and the (empty) space where this CO ₂ escapes The light non-condensable gas fills and rises upward, and rises to the non-condensable gas collection space. This non-condensable gas is mostly composed of a trace amount of oxygen (6 mol%) that is oversupplied to the combustion chamber. As the circulation blade rotates, this collected non-condensable gas is sucked into the vacuum pump as shown, transported to the exhaust minicooler, slightly cooling the inlet turbine exhaust, and discharged to the atmosphere. With this cold air circulation pipe, the low-temperature cold air of the CO ₂ cooler chamber is sucked in and ejected from the upper ceiling, whereby the turbine exhaust is effectively cooled. In addition, in order to more effectively cool the turbine exhaust, a plurality of water spray nozzles are installed next to the cold air outlet of the cold air circulation piping, from which steam is condensed (preceding exhaust), and steam spray is ejected from the ceiling. In the steam cooler below the water spray nozzle, the liquid refrigerant nitrogen flows through the tube, the inlet exhaust is cooled, and then the inlet exhaust in the steam cooler is finally cooled and condensed with water vapor spray, and the non-condensable gas and the turbine exhaust CO ₂ goes up to the upper CO ₂ cooler. Introduced exhaust CO ₂ is cooled to -13°C with refrigerant oxygen in this CO ₂ cooler and discharged (collected) by the vacuum pump, and steam in the turbine exhaust is cooled and condensed, as shown (Hot Well) It collects in the hot well, then is transferred to the tube of the exhaust heat absorber by a condensate pump, cools the subsequent turbine exhaust with a refrigerant, is sucked into the vacuum pump, and is transferred to the steam (StmHtr) heater of the turbine exhaust heat recovery system (FIG. 4). .

The 110°C turbine exhaust, which is (suctioned) into the present exhaust cooler configured as described above, enters the exhaust heat absorber at the inlet and flows into the tube at a saturation temperature of 60°C (pre-plural), and is cooled. do. That is, this gas-condensate is 110°C turbine exhaust heat, while evaporating into steam, it absorbs the turbine exhaust heat and raises the temperature to 90°C. Next, as this turbine exhaust enters the center, it is directly cooled by the cold gas emitted from the cold air circulation pipe and water vapor and spray emitted from the water spray nozzle, and then, in the steam cooler, the refrigerant With nitrogen, further cooled, condensate, and then further cooled with refrigerant oxygen flowing through the tubes in the steam cooler, the turbine (exhaust) steam is cooled to 60°C (0.2bar saturation temperature 60.06°C) and finally condensed. Next, in this steam cooler, CO ₂ and non-condensable gases, which are lighter than water vapor, rise to a higher-mounted CO ₂ cooler. In this CO ₂ cooler, this CO ₂ is further cooled with refrigerant oxygen, and this cooled CO ₂ is sucked (collected) and discharged by a vacuum pump mounted below. In this CO ₂ cooler, a small amount of CO ₂ and non-condensable gases are sucked into the upper ceiling circulation pipe and returned to the front of the water spray nozzle in the center of this exhaust cooler, whereby the cold air of this CO ₂ cooler is circulated to make the turbine exhaust more Cools effectively.

The temperature of the CO ₂ captured in the CO ₂ cooler is determined by the degree to which the refrigerant oxygen cools the CO ₂ . It is known that this CO ₂ dissolves well in carbonated water in water at low temperature and high pressure. This CO ₂ cooling temperature is determined at an economical temperature and pressure at which CO ₂ is easily dissolved in carbonated water in water in the course of realizing the present invention in the future. CO ₂ captured at -13℃ in this exhaust cooler is melted into carbonated water in a mixer where cooling water and (catalytic action) seawater are mixed (Mixer), and this carbonated water (recently developed CO ₂ produces electricity and hydrogen) is supplied to the hydrogen production system to produce hydrogen. A technology for producing hydrogen with this CO ₂ does not fall within the scope of the patent of the present invention. Ammonia (NH ₃ ), an optimal storage and transport medium for hydrogen, is produced from this produced hydrogen and nitrogen used as a refrigerant, and clean energy hydrogen is stored in NH ₃ . In order to store hydrogen with a boiling point of -252.88℃ as a liquid, ultra-high pressure is required, but this NH ₃ can store 1.5 times more than liquid at a low pressure of only 8.5 atm.

Since ultra-high pressure is required to store this hydrogen as a liquid, as a storage means of this hydrogen, for example, a magnesium-nickel alloy, a titanium (Ti)-manganese alloy, etc., as methane (CH ₄ ) Hydrogen storage alloys, in which hydrogen is stored, have been studied, as hydrogen is stored, but in ammonia (HN ₃ ), which is mainly used as a raw material for fertilizer, this hydrogen is 1.5 times more than liquid, already liquefied and stored at low pressure at room temperature. Therefore, HN ₃ has recently attracted attention as a hydrogen storage means. Recently, a new technology has been developed in which this HN ₃ is produced at a low pressure and low temperature of 45°C at a pressure of 1 atmosphere, and a hydrogen extraction technology in which hydrogen is separated from nitrogen at 450°C or less in this HN ₃ has been developed. In other words, this hydrogen is easily produced from 78% nitrogen in the atmosphere, HN ₃ is stored in this container (HN ₃ ), and this hydrogen can be easily taken out and used (in the future) from this container (HN ₃ ). . In the present invention, CO ₂ constantly produced by combustion is not captured and released into the atmosphere, hydrogen is produced from this CO ₂ , and NH ₃ is produced from nitrogen using this hydrogen as a refrigerant, and eventually this clean energy hydrogen This NH ₃ is stored.

In a gas turbine, turbine exhaust is cooled so that steam is condensed and carbon dioxide (CO ₂ ) is captured, and the entire amount of turbine exhaust heat is recovered, so that high power generation efficiency is achieved, and in addition, hydrogen is produced from CO ₂ produced by combustion; Ammonia (NH ₃ ) is produced from this hydrogen and nitrogen used as a refrigerant for pure oxygen combustion, and eventually, hydrogen is produced from the CO ₂ in question, and 1.5 times more than liquid is stored in NH ₃ , thereby CO ₂ It is characterized by being configured to realize neutrality.

Code Description None.

Claims (5)

In a gas turbine, oxygen and nitrogen produced from air are used as refrigerants, only oxygen is injected into the combustion chamber, and CO ₂ as a working fluid is preheated with turbine exhaust heat by means of a heat pump, injected into the combustion chamber, and recirculated to obtain pure oxygen Combustion is implemented,
(Claim 2) The turbine exhaust is sucked into the exhaust cooler (Fig. 2), cooled and condensed, and the pre-condensate that has already been cooled and recovered evaporates into steam in the exhaust heat (Exh.Heat Absorber) absorber as turbine exhaust heat. While cooling the turbine exhaust, the temperature is raised to 90 ° C, and the turbine exhaust heat is absorbed, (FIG. 4) is sucked into the vacuum pump of the turbine exhaust heat recovery system, transferred to the steam (StmHtr) heater, and the exhaust CO ₂ is -13 After this CO ₂ is pressurized at 20 bar and the temperature rises above 360 ° C, the liquid refrigerant nitrogen, in the CO ₂ condenser, cools and liquefies the CO ₂ at -20 ° C, raises the temperature to 340 ° C, and this liquid phase of CO ₂ is pressurized above the critical pressure (73 bar), and (FIG. 4) the supercritical fluid (ScCO ₂ PreHtr#1) of the turbine exhaust heat recovery system is pumped to preheater #1 and preheater #2,
(Claim 3) (FIG. 4) In the turbine exhaust heat recovery system, by means of a heat pump, (supercritical fluid) ScCO2 PreHtr#1 and ScCO2 PreHtr#2 are generated as supercritical fluids, preheated to 400 ° C. or higher, and the above - Some (16 mol) liquid CO2 at 20 ° C is pumped to preheater # 3 of the supercritical fluid (ScCO2 PreHtr # 3) of the nitrogen liquefaction cooling system (FIG. 5),
(Claim 4) This -20℃ CO2 is produced as a supercritical fluid by pressurizing 1atm nitrogen at 30bar and raising the temperature to 650℃, and preheating it to 600℃ or higher,
(Claim 5) Turbine exhaust CO ₂ produced by combustion is cooled (collected) to -13°C and discharged with refrigerant oxygen, further cooled to -50°C, and 5°C (plural) cooling water and seawater produced by combustion E, the CO ₂ is dissolved in carbonated water in a mixer and supplied to a system in which hydrogen is produced, and exhaust cooling, exhaust heat recovery and CO 2 capture device by gas-condensation and pure oxygen combustion configured to produce hydrogen and how to operate heat pumps and carbon neutrality.
3. In the exhaust cooler (FIG. 3), an exhaust heat absorber is installed at the inlet where the turbine exhaust is sucked, and an exhaust mini cooler is installed next to the rear end thereof, and then installed on the far right side. The cold air (cold gas) is sucked in from the ceiling of the CO ₂ cooler chamber,
A plurality of cold air circulation pipes are equipped, and at the T-junction above the inlet of the cold air circulation pipe, (FIG. 3) a blade through which cold air from the CO ₂ cooler chamber is suctioned and circulated is installed, right above the blade, (combustion unreacted) ) A collection space for non-condensable gases such as oxygen and _CO is formed, and a vacuum pump that blows out this non-condensable gas is installed. As it circulates, non-condensable gas is collected, and this non-condensable gas is configured to be removed, and after the cold air circulation pipe, as condensate that has already been cooled and condensed, water vapor spray is ejected from the ceiling.
A plurality of water spray nozzles are installed, and below the water spray nozzle, a steam cooler by refrigerant nitrogen is installed, followed by a vapor cooler by oxygen refrigerant. , On the far right, a CO ₂ cooler is installed higher than the steam cooler, and a vacuum pump is installed to cool (capture) and discharge the CO ₂ introduced under the CO ₂ cooler (-13℃). ,
Turbine exhaust sucked into this exhaust cooler is cooled and condensed, and the already cooled pre-condensate is transferred as a refrigerant to a pre-condensate pump to an exhaust heat absorber tube, so that the subsequent turbine exhaust is In the furnace, it is cooled, it is effectively cooled (exhaust air) by sprays of cold air and water vapor ejected from the ceiling, in steam coolers and steam coolers, with refrigerants nitrogen and oxygen, steam is cooled and finally condensed, CO ₂ produced by combustion Exhaust cooling, exhaust heat recovery, and CO2 capture device by gas-condensate and pure oxygen combustion configured to go up to the CO ₂ cooler, be further cooled with refrigerant oxygen, and (collect) discharged at below zero (-13°C). The method according to claim 1, (FIG. 4) in the steam (StmHtr) heater of the exhaust heat recovery system, by means of a heat pump, steam is heated at 340 ° C. nitrogen to 325 ° C. (Boost up), and heated to 1 atm. After pressurizing and raising the temperature to 610°C, some (32 mol%) CO ₂ of the liquid phase above the -20°C critical pressure (73 bar) is heated to 595°C with this 610°C steam in the supercritical fluid (ScCO2 PreHtr#1) preheater #1. , which is produced as a supercritical fluid and preheated to 500 ° C or higher, and some (32 mol%) CO ₂ of this -20 ° C liquid phase, in the supercritical fluid (ScCO2 PreHtr # 2) preheater # 2, the above 340 ° C An exhaust heat recovery heat pump operating method by gas-condensation and pure oxygen combustion, which is generated as nitrogen and supercritical fluid and is configured to be preheated to 300 ° C or higher. The method of claim 1, wherein the -20 ° C. part (16 mol%) CO ₂ (FIG. 5) in the supercritical fluid (ScCO ₂ PreHtr # 3) preheater # 3 of the nitrogen liquefaction cooling system, pressurized 1 atm nitrogen to 30 bar with a compressor Nitrogen heated to 650 ° C, produced as a supercritical fluid, preheated to more than 600 ° C, this 30 bar nitrogen is cooled to -5 ° C, reducing the nitrogen compressor load, then this nitrogen is efficiently cooled and liquefied, The preceding 1 atm expansive nitrogen cools the -5°C 30 bar compressed nitrogen in the secondary cooler, and is mostly stored in a low temperature nitrogen tank, so that 1 atm nitrogen is not compressed below 650° C. A method of operating a heat pump for exhaust cooling and exhaust heat recovery by gas-condensate and pure oxygen combustion, configured to be controlled, mixed with high-temperature nitrogen storage tank nitrogen, and re-input to the compressor. The method of claim 1, wherein the turbine exhaust CO ₂ generated by combustion is cooled (captured) to -13 ° C, discharged, pressurized at 1 atm with a vacuum pump, heated to 100 ° C, and external (CO ₂ ExCooler) In a CO ₂ cooler, It is cooled to -50℃ with liquid refrigerant nitrogen, and the steam generated by combustion is cooled to 5℃ with refrigerant (17mol%) nitrogen in (Stm Cond#2), and a mixer (Mixer) in which this cooling water and seawater are mixed ), the -50°C CO ₂ is dissolved in carbonated water, and then this carbonated water is supplied to the system, where hydrogen is produced as CO ₂ , hydrogen is produced, and ammonia as nitrogen utilized as a refrigerant with this hydrogen (NH3) is configured to be manufactured, thereby economically realizing the neutrality of _{CO 2} constantly generated in power plants.

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