JP5180805B2 - Gas turbine system - Google Patents

Description

  The present invention relates to a gas turbine system having a gas turbine that rotates a turbine with energy generated by burning liquid fuel.

  The gas turbine system uses liquid fuel (oil fuel) such as heavy oil, light oil, and kerosene. This liquid fuel is injected into the combustor, dispersed, burned, and the turbine is rotated by the energy generated by the combustion. There is a system that takes out the output. In this gas turbine system, nitrogen oxide (NOx) and soot are generated during combustion of liquid fuel. As a method for reducing the discharge of nitrogen oxides and soot, there is a method of mixing water into liquid fuel.

  In addition, as a device for mixing liquid fuel and other fuel, in Patent Document 1, in a gas turbine combustor using gas fuel, the temperature of the fuel gas or higher than the temperature of the fuel gas before being supplied to the combustor. Liquid fuel that can be vaporized at a low temperature is injected in the form of a liquid, and the liquid fuel is vaporized at the temperature of the fuel gas, and is mixed with the fuel gas uniformly and supplied to the combustor. A premixing unit that premixes a fuel mixture of the fuel gas and vaporized liquid fuel with compressed air and then injects the fuel into the combustor, and burns the premixer in the combustor to A gas turbine combustor for generating a combustion gas to drive is described. The gas turbine described in Patent Literature 1 is a device that mixes liquid fuel to be vaporized into gaseous fuel, but as described in Patent Literature 1, the gas turbine mixes before injecting (injecting) into the combustor. Thus, the two substances can be mixed.

JP 2008-128010 A

  Here, by injecting and burning the liquid fuel to which water is added, soot generated during the combustion reaction and CO can be reduced. Further, by atomizing the water added to the liquid fuel, when the liquid fuel is injected, the water is boiled and expanded, and the liquid fuel can be atomized. Since the liquid fuel can be atomized, the liquid fuel can be dispersed in the combustor on average, and the liquid fuel can be burned more appropriately in the entire combustion chamber. Thus, the generation of soot can be further reduced by appropriately burning the liquid fuel.

  However, since the gas turbine has a high pressure in the combustor, the boiling point of water becomes high, and the difference in boiling point from liquid fuel becomes small. Therefore, there is a problem that it is difficult to atomize the liquid fuel due to boiling expansion of water. This problem becomes more prominent as the pressure in the combustor increases. If the atomization of the liquid fuel is insufficient, soot generation cannot be sufficiently suppressed.

  This invention is made | formed in view of the above, Comprising: It aims at providing the gas turbine system which can suppress suitably generation | occurrence | production of soot and generation | occurrence | production of nitrogen oxides.

  In order to solve the above-described problems and achieve the object, the present invention is a gas turbine system including a combustor and a turbine, and the turbine is produced by combustion gas obtained by burning liquid fuel in the combustor. A rotating gas turbine; fuel supply means for supplying liquid fuel to a combustor of the gas turbine; carbon dioxide recovery means for recovering carbon dioxide contained in exhaust gas discharged from the gas turbine as a liquid or solid; And carbon dioxide mixing means for mixing liquid or solid carbon dioxide recovered by the carbon dioxide recovery section into the liquid fuel of the fuel supply means.

  The carbon dioxide contained in the exhaust gas is recovered by the carbon dioxide recovery means, and further recovered, liquefied or solidified carbon dioxide is mixed into the liquid fuel before injection, so that liquid fuel droplets are formed in the combustor. More fine particles can be dispersed. Thereby, liquid fuel can be combusted suitably in a combustor, and generation | occurrence | production of soot and generation | occurrence | production of nitrogen oxide can be suppressed suitably. Moreover, the carbon dioxide (CO2) contained in the exhaust gas can be recovered, and furthermore, the carbon dioxide contained in the exhaust gas can be used efficiently.

  Here, it is preferable that the gas turbine system further includes a mixing mechanism for mixing the carbon dioxide and the liquid fuel.

  By providing the mixing mechanism, liquid carbon dioxide or solid carbon dioxide can be dispersed more uniformly in the liquid fuel, and when the liquid fuel is injected into the combustor, it can be more finely atomized.

  Moreover, it is preferable to have a cooling mechanism that cools the turbine with air cooled by the liquid fuel mixed with the carbon dioxide.

  The turbine can be efficiently cooled by mixing the low-temperature liquid or solid carbon dioxide and cooling the air with the liquid fuel having a low temperature and cooling the turbine with the cooled air. Moreover, since the turbine can be efficiently cooled, the amount of air used for cooling can be reduced.

  Furthermore, it is preferable to have water addition means for adding water or ice to liquid or solid carbon dioxide held by the carbon dioxide addition means.

  By adding water to carbon dioxide and mixing carbon dioxide and water into the liquid fuel, the liquid fuel can be suitably burned in the combustor, and soot generation and nitrogen oxide generation are suitably suppressed. be able to.

  Moreover, it is preferable that the said water | moisture-content addition means extracts a water | moisture content from the waste gas discharged | emitted from the said gas turbine.

  By extracting moisture from the exhaust gas, it is not necessary to newly provide a water tank, and the apparatus configuration can be simplified.

  The gas turbine system according to the present invention can suitably suppress the generation of soot and the generation of nitrogen oxides, can recover CO2 contained in the exhaust gas, and can efficiently utilize the CO2 contained in the exhaust gas. There is an effect that can be done.

  Hereinafter, an embodiment of a gas turbine system according to the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by this embodiment.

  FIG. 1 is a block diagram showing a schematic configuration of an embodiment of a gas turbine system of the present invention. As shown in FIG. 1, the gas turbine system 10 includes a gas turbine 12, a fuel supply unit 14, a steam turbine 16, a CO2 recovery unit 18, and a CO2 mixing unit 20.

The gas turbine 12 is a means for extracting output from combustion gas obtained by burning liquid fuel, and includes a compressor 22, a turbine 24, a support shaft 26, and a combustor 28.
The compressor 22 is rotated to compress and discharge air. The turbine 24 is a member that rotates when combustion gas is blown. The support shaft 26 supports the compressor 22 and the turbine 24, and rotates the compressor 22 and the turbine 24 integrally. The combustor 28 is disposed between the compressor 22 and the turbine 24. The combustor 28 burns fuel supplied from the fuel supply means 14 described later in a state where compressed air is supplied from the compressor 22, heats and expands the air, and the expanded air, that is, the combustion gas Is supplied to the turbine 24. In the gas turbine 12, the air compressed by the compressor 12 is heated by the combustor 28, expanded into combustion gas, and the combustion gas is supplied to the turbine 24 to rotate the turbine 24. Further, the compressor 12 also rotates using the rotation of the turbine 24 as a driving force, and compresses the air.

  The fuel supply unit 14 is a unit that supplies fuel to the gas turbine 12, and includes a fuel supply pump 30 and a fuel mixing unit 32. The fuel supply pump 30 is a pump that compresses liquid fuel and injects it toward the combustor 28. The fuel mixing section 32 is disposed between the fuel supply pump 30 and the combustor 28 on the liquid fuel flow path, stirs the liquid fuel, and mixes the liquid CO2 and liquid fuel mixed by the CO2 mixing means 20 described later. And liquid CO2 is dispersed in the liquid fuel. Here, as the fuel mixing section 32, various mixing means for mixing a plurality of types of liquids can be used, but a static mixer type micro droplet generator is preferably used. By using the static mixer system, it is possible to mix liquid CO2 and liquid fuel and disperse liquid CO2 in the liquid fuel without providing a drive unit. By using the static mixer type micro droplet generator, droplets of liquid CO 2 having a droplet diameter of 5 μm to 30 μm can be generated in the liquid fuel.

  The steam turbine 16 is a means for extracting output from the heat of exhaust gas discharged from the gas turbine 12, and includes a heat exchanger 34 and a turbine 36. The heat exchanger 34 absorbs heat from the exhaust gas discharged from the gas turbine 12 into a liquid in a pipe disposed adjacent to the pipe through which the exhaust gas flows, and generates a vapor by evaporating the liquid. The heat exchanger 34 supplies the steam generated through the piping to the turbine 36. The turbine 36 is a member that rotates when steam (air) is blown, and is rotated when the steam supplied from the heat exchanger 34 is blown. Thus, the steam turbine 16 takes out an output as rotational force from the heat of exhaust gas.

  The CO2 recovery means 18 is means for recovering CO2 (carbon dioxide) contained in the exhaust gas discharged from the gas turbine 12, and includes a CO2 extraction mechanism 40, a CO2 liquefaction pump 42, and a CO2 storage unit 44. The CO2 extraction mechanism 40 is disposed on the downstream side of the heat exchanger 34 on the path of the exhaust gas discharged from the gas turbine 26, and extracts CO2 from the exhaust gas. That is, CO2 contained in the exhaust gas is separated and recovered. The CO2 liquefaction pump 42 is a pump that pressurizes gas, pressurizes the CO2 extracted by the CO2 extraction mechanism 40, and liquefies CO2. Since CO2 is liquefied when it is in a constant pressure range and a constant temperature range, the CO2 liquefaction pump 42 controls the temperature as well as the pressure so that CO2 is in a constant pressure range and a constant temperature range. The CO 2 storage unit 44 is a tank that stores liquefied CO 2, and stores the CO 2 liquefied by the CO 2 liquefaction pump 42.

  The CO2 mixing means 20 is connected to a pipe connecting the CO2 liquefaction pump 42 and the CO2 storage unit 44 and a pipe connecting the fuel supply pump 30 and the mixing means 32. The CO2 mixing unit 20 mixes the CO2 liquefied by the CO2 recovery unit 18 with the liquid fuel flowing from the fuel supply pump 30 toward the fuel mixing unit 32.

  The gas turbine system 10 is configured as described above, and CO2 contained in the exhaust gas discharged from the gas turbine 12 is recovered and liquefied by the CO2 recovery means 18. Thereafter, the liquefied CO 2 is mixed into the liquid fuel sent from the fuel supply pump 30 by the CO 2 mixing means 20. Thereafter, the liquid fuel is mixed with the liquid CO 2 by the fuel mixing unit 32 and then injected into the combustor 28 and dispersed in the combustor 28 as fine droplets.

  The liquid fuel that has been injected into the combustor 28 and turned into fine droplets rapidly evaporates liquid CO2 having a boiling point lower than that of the liquid fuel mixed therein, resulting in a micro explosion. When the liquid CO 2 mixed with the liquid fuel undergoes a micro explosion, the liquid fuel becomes finer droplets and is dispersed in the combustor 28. The liquid fuel dispersed in the combustor 28 is then combusted to heat and expand the air in the combustor. The air heated and expanded in the combustion chamber is supplied to the turbine 24 as an air flow to rotate the turbine 24. The air flow that rotates the turbine 24 flows through the piping as exhaust gas, heats the water in the adjacent piping with the heat exchanger 34, collects CO 2 with the CO 2 recovery mechanism 40, and discharges it to the outside. Further, the water heated by the exhaust gas in the heat exchanger 34 is supplied as steam to the turbine 36 to rotate the turbine 36. The gas turbine system 10 rotates the turbine 24 and the turbine 36 with the energy generated by burning the liquid fuel, and extracts the output. Further, CO 2 generated when the liquid fuel is burned is recovered by the CO 2 recovery means 18.

  The gas turbine system 10 uses water or liquid CO2 having a boiling point significantly lower than that of the liquid fuel as a liquid to be mixed with the liquid fuel, so that when the liquid fuel is injected into the combustor 28, even under high pressure conditions, It is possible to evaporate the liquid CO2 more reliably, to generate a micro explosion of the CO2, and to make the liquid fuel into fine droplets. Since the liquid fuel can be dispersed as fine droplets in the combustor 28, the amount of nitrogen oxide (NOx) and soot generated during the combustion of the liquid fuel can be reduced.

  Further, by using CO2 discharged from the gas turbine 12 as CO2 to be mixed into the liquid fuel, there is no need to separately provide a tank that stores the liquid CO2. Further, the recovered CO 2 can be efficiently used while preventing the exhaust gas discharged from the gas turbine 12 from being discharged to the outside.

  Next, another embodiment of the gas turbine system of the present invention will be described with reference to FIG. FIG. 2 is a block diagram showing a schematic configuration of another embodiment of the gas turbine system of the present invention. The gas turbine system 50 shown in FIG. 2 has the same configuration as that of the gas turbine system 10 shown in FIG. Therefore, the same components are denoted by the same reference numerals, and detailed description thereof will be omitted. Hereinafter, points peculiar to each load measuring device will be mainly described. The gas turbine system 50 includes a gas turbine 12, a fuel supply unit 14, a steam turbine 16, a CO 2 recovery unit 18, a CO 2 mixing unit 20, and a water recovery / addition unit 52.

  The water recovery / addition means 52 is means for recovering moisture from the exhaust gas discharged from the gas turbine 12 and adding it to the liquid CO 2 mixed with the liquid fuel. The water recovery / addition section 54, the purification section 56, and the addition section 58 are used. And have. The water separation unit 54 is disposed between the heat exchanger 34 and the CO2 recovery mechanism 40 in the exhaust gas flow path (pipe through which the exhaust gas flows), and separates and recovers moisture contained in the exhaust gas from the exhaust gas. . The exhaust gas from which moisture has been removed by the water separation unit 54 is sent to the CO 2 recovery mechanism 40. The purification unit 56 is connected to the water separation unit 54 and removes impurities contained in the water separated by the water separation unit 54 to make pure water. The addition unit 58 is a unit that mixes two liquids, and is connected to a pipe through which the liquid CO2 flows between the CO2 liquefaction pump 42 and the CO2 mixing unit 20, and further, a water separation unit via the purification unit 56. 54. The addition unit 58 adds the water, which has been separated by the water separation unit 54 and from which impurities have been removed by the purification unit 56, to the liquid CO 2 flowing from the CO 2 supply pump 42 toward the CO 2 mixing means 20. The liquid CO2 to which water has been added becomes hydrated.

  The gas turbine system 50 is configured as described above. Water is added and hydrated liquid CO2 is mixed with the liquid fuel, and the liquid fuel mixed with the hydrated liquid CO2 is injected into the combustor 28. As a result, when the liquid fuel is injected into the combustor 28, the liquid CO 2 can be more reliably evaporated even under high pressure conditions, and a micro explosion of CO 2 can be generated, and the liquid fuel is made into fine droplets. be able to. Since the liquid fuel can be dispersed as fine droplets in the combustor 28, the amount of nitrogen oxide (NOx) and soot generated during the combustion of the liquid fuel can be reduced. Furthermore, by mixing water in addition to liquid CO2, the amount of nitrogen oxide (NOx) and soot generated during the combustion of the liquid fuel can be further reduced by the combustion reaction between the liquid fuel and water. it can.

  Here, in the gas turbine system 50, since the exhaust gas can be used effectively, the moisture contained in the exhaust gas is recovered, and the recovered water is added (mixed) to the liquid CO2. However, the present invention is limited to this. Not. A water tank may be provided, and water may be added from the tank to the liquid CO2. In this case, a water tank is provided, and it is necessary to replenish water and replace the tank.

  In the gas turbine system 50, liquid CO2 and water are mixed and hydrated. However, it is sufficient that the liquid fuel can be mixed with liquid or solid CO2 and liquid or solid water. For example, liquid CO2 and water may be mixed with the liquid fuel through separate paths. Also, when using solid CO 2, that is, dry ice, or solid water, that is, ice, dry ice and / or ice in a finely pulverized state is liquid so that the dry ice and ice are dispersed in the liquid fuel. It is preferable to mix in fuel. By finely pulverizing, dry ice and / or ice can be uniformly dispersed in the liquid fuel in the fuel mixing section 32.

  Next, still another embodiment of the gas turbine system of the present invention will be described with reference to FIG. FIG. 3 is a block diagram showing a schematic configuration of another embodiment of the gas turbine system of the present invention. The gas turbine system 70 shown in FIG. 3 has the same configuration as that of the gas turbine system 10 shown in FIG. 1 except that the heat turbine 76 is provided. Therefore, the same components are denoted by the same reference numerals, and detailed description thereof will be omitted. Hereinafter, points peculiar to each load measuring device will be mainly described. The gas turbine system 70 includes a gas turbine 12, a fuel supply unit 14, a steam turbine 16, a CO 2 recovery unit 18, a CO 2 mixing unit 20, a water recovery addition unit 52, and a turbine cooling unit 72.

  The turbine cooling means 72 is means for air-cooling the turbine 24 and includes a cooling pipe 74 and a heat exchanger 76. The cooling pipe 74 is a pipe connected to the compressor 22 and the turbine 24, and supplies a part of the compressed air to the cooling passage of the turbine 24. The heat exchanger 76 is a mechanism that connects the cooling pipe 74, the fuel mixing unit 32, and the combustor 28, and exchanges heat with the pipe 78 through which the liquid fuel flows. Here, the liquid fuel is a low-temperature liquid because the liquid CO2 is mixed. Therefore, the heat exchanger 76 cools the air flowing through the cooling pipe 74 by the pipe 78, and makes the air supplied to the turbine 24 cooler air.

  The gas turbine system 70 is configured as described above, and air that cools the turbine 24 using the cooling power of the liquid fuel whose temperature is low by mixing liquid or solid CO 2 having a low temperature. By lowering the temperature, the amount of air used for cooling can be reduced, and the turbine can be efficiently cooled. Further, since the amount of air used for cooling can be reduced, the air used for cooling the turbine 24 out of the air compressed by the compressor 22 can be reduced. Thereby, more air compressed by the compressor 22 can be supplied to the combustor 28, and the energy efficiency of the gas turbine system 70 can be increased. In addition, since the temperature of the liquid fuel can be increased by the heat exchanger 76, the liquid fuel can be easily burned in the combustor 28.

  As described above, the gas turbine system according to the present invention is useful for reducing soot and nitrogen oxides contained in the exhaust gas discharged from the gas turbine, and particularly for a gas turbine system having a carbon dioxide recovery mechanism. Suitable for use.

It is a block diagram showing a schematic structure of one embodiment of a gas turbine system of the present invention. It is a block diagram which shows schematic structure of other embodiment of the gas turbine system of this invention. It is a block diagram which shows schematic structure of other embodiment of the gas turbine system of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 50, 70 Gas turbine system 12 Gas turbine 14 Fuel supply means 16 Steam turbine 18 CO2 collection | recovery means 20 CO2 mixing means 22 Compressor 24 Turbine 26 Support shaft 28 Combustor 30 Fuel supply pump 32 Fuel mixing part 34, 76 Heat exchanger 36 Turbine 40 CO2 Extraction Mechanism 42 CO2 Liquefaction Pump 44 CO2 Storage Unit 52 Water Recovery Addition Unit 54 Water Separation Unit 56 Purification Unit 58 Addition Unit 72 Turbine Cooling Unit 74 Cooling Pipe 78 Pipe

Claims (4)

A gas turbine comprising a combustor and a turbine, wherein the turbine is rotated by a combustion gas obtained by burning liquid fuel in the combustor;
Fuel supply means for supplying liquid fuel to the combustor of the gas turbine;
Carbon dioxide recovery means for recovering carbon dioxide contained in the exhaust gas discharged from the gas turbine as a liquid or solid;
Carbon dioxide mixing means for mixing liquid or solid carbon dioxide recovered by the carbon dioxide recovery section into the liquid fuel of the fuel supply means,
A gas turbine system comprising: water addition means for adding water or ice to liquid or solid carbon dioxide held by the carbon dioxide mixing means .   The gas turbine system according to claim 1, further comprising a mixing mechanism that mixes the carbon dioxide and the liquid fuel.   The gas turbine system according to claim 1, further comprising a cooling mechanism that cools the turbine with air cooled by the liquid fuel mixed with carbon dioxide. The gas turbine system according to any one of claims 1 to 3, wherein the moisture adding unit extracts moisture from exhaust gas discharged from the gas turbine.

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