JP2007285122A - Gas turbine engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas turbine engine which is operated by only one biomass fuel without using any starting fuel derived from a fossil fuel, and capable of reducing emission of carbon dioxide, nitrogen oxide and smoke from the gas turbine engine. <P>SOLUTION: A liquid fuel containing vegetable oil methyl ester as a component is supplied to a combustor 6. A means is provided, which raises the temperature of the fuel in a nozzle at a fore end of a spray nozzle 3 for supplying the fuel to the combustor 6 to the temperature exceeding the pour point of the liquid fuel. The liquid fuel to be sprayed from the spray nozzle 3 as particles with compressed air to be supplied to the combustor 6 is burned, and the generated combustion gas is supplied to a turbine 9 to generate the power. By using the vegetable oil methyl ester for the fuel, the emission of carbon dioxide, nitrogen oxide and smoke is suppressed. By raising the fuel temperature at the fore end of the spray nozzle, the combustion stability equivalent to that of the liquid fuel derived from fossil fuel is obtained. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a gas turbine engine for liquid fuel. More specifically, the present invention relates to a liquid fuel gas turbine engine using vegetable oil methyl ester as a fuel.

  In recent years, it has been required to suppress the generation of nitrogen oxides (NOx) and suspended particulate matter (SPM) that adversely affect the environment, and the use of biomass fuel is required as a fuel to replace petroleum.

  Gas turbine engines that use liquid fuels derived from fossil fuels such as light oil and heavy oil A emit higher concentrations of NOx and smoke that causes SPM than gas turbine engines that use gas fuels such as LNG. There is a possibility. For this reason, the reduction has been achieved by improving the fuel injection method and by devising the structure of the burner, but in particular, NOx has not been sufficiently reduced, and an expensive flue gas denitration device has been installed. Has been done.

On the other hand, CO ₂ but Japan reduction commitments of carbon dioxide (CO ₂₎ emissions of greenhouse gases such as are imposed by the fastening of the Kyoto Protocol, which is discharged by the combustion of biomass, air in biological growth process Since it is CO ₂ absorbed from inside, combustion of biomass does not increase CO ₂ . For this reason, replacing petroleum-based fuels with biomass fuels greatly contributes to the reduction of CO ₂ emissions. Furthermore, in Japan, the “Special Measures Law Concerning the Use of New Energy by Electric Power Companies” (RPS Law) has been enforced, and electricity generated by new energy, including biomass, is used at a certain rate for electric power companies. It is obligatory.

  Therefore, a method of mixing solid biomass fuel such as wood chips into coal and burning it with a power generation boiler, a method of burning with a power generation gas turbine engine, and a method of gasifying and burning with a power generation gas turbine engine are being studied. . However, these methods using solid biomass fuel such as wood chips have a low calorific value per mass of solid biomass, poor collection efficiency and transport efficiency, and also require processing of the generated ash or slag, which is economical. There are problems such as inferiority.

  For example, Patent Document 1 discloses a method of burning solid biomass fuel with a gas turbine engine. In this method, fossil fuel and biomass fuel are appropriately selected to generate combustion gas, impurities contained in the generated combustion gas are removed by a cyclone separator and then supplied to the gas turbine, and the cyclone separator outlet temperature is 800 It is necessary to keep the temperature below ℃. The reason is that the calorific value of the solid biomass fuel is low, the start-up operation and partial load operation cannot be performed only with the biomass fuel, the ash adheres to the turbine blades unless the ash generated by the combustion of the solid biomass fuel is removed, Since the causative substance of dioxin is contained in the biomass fuel, it is caused by generating dioxin unless the temperature is higher than 800 ° C.

  Further, Patent Document 2 discloses a method in which solid biomass fuel or the like is gasified and burned by a power generation gas turbine engine. In this method, a water spray means is provided in a compressor of gasified gaseous fuel, water is sprayed in the process of compressing the gaseous fuel and evaporated in the compressor, and the gas temperature accompanying the compression using the endothermic effect at this time is used. It is necessary to suppress the rise of the gas and to increase the gas temperature of the gaseous fuel to 300 ° C. or higher. The reason for this is that compressing high-temperature gaseous fuel further increases the temperature and the compressed energy becomes the same level as the energy generated by the gas turbine, resulting in a decrease in the output energy, and biomass. Combustible gas that gasifies etc. contains a component called tar that liquefies at low temperatures, and when the gas temperature becomes low, it becomes a highly viscous liquid and adheres to piping and equipment, causing problems such as clogging It is due to that. In Patent Document 2, as a conventional method for avoiding the problem due to the tar content, a method of thermally decomposing the tar content by increasing the gasification temperature and a method of removing the tar by washing the gas with water are described. In addition, there are disadvantages such as generation of energy loss and complicated equipment, and furthermore, as a conventional method that does not require compression of gaseous fuel, there is a method of performing gasification by pressurization, but a pressure vessel is required, It presents the drawbacks of creating safety problems and increasing operating costs.

  A method for burning these solid or gasified biomass fuels with a gas turbine engine using vegetable oil as a fuel has also been proposed (Patent Documents 3 and 4). In the case of a liquid fuel containing vegetable oil methyl ester as a component, if sprayed simply from a fuel nozzle, the spray particle size increases due to high viscosity, making ignition difficult. In the case of liquid fuel, if the fuel remains in a liquid state, it cannot react and burn with air, but it reacts with air and burns only when the liquid evaporates into a gas. It is necessary to create a situation that easily evaporates. For this reason, it is necessary to start with a petroleum-based fuel that is more easily ignited. Therefore, in these methods, gas fuel such as kerosene and light oil or gas fuel such as city gas is burned at the start-up to raise the combustion chamber temperature, and then the plant waste oil such as modified tempura oil is burned. The gas turbine is driven.

JP 2004-218532 A JP2002-221047 JP2003-184576 JP2004-11628

  However, the method described in Patent Document 1 requires two systems of fossil fuel and biomass fuel supply equipment, which increases equipment costs and complicates control. In addition, a cyclone separator is required, resulting in an increase in equipment size and an increase in equipment costs, and there is a risk of cyclone wear due to high-temperature ash. Furthermore, it is necessary to manage the temperature of the cyclone outlet, and the control for that is complicated.

  In addition, the method of Patent Document 2 requires pure water, and also requires a water supply device and a control device, which increases equipment costs and operation costs. In addition, energy loss due to gasification of fuel cannot be prevented. Furthermore, the poor collection and transportation efficiency of solid biomass fuels and the need for processing costs for the generated ash or slag remain as common challenges. Furthermore, trace components such as sodium and potassium contained in solid biomass fuel deteriorate materials such as turbines, but no countermeasures have been taken.

  In addition, the methods described in Patent Documents 3 and 4 require two supply devices for starting fuel and biomass fuel that use liquid fuel or gaseous fuel derived from fossil fuel, which increases equipment costs and complicates control. There's a problem.

  An object of the present invention is to provide a gas turbine engine for liquid fuel that efficiently uses biomass fuel and emits less carbon dioxide, nitrogen oxides, and smoke. A further object of the present invention is to provide a gas turbine engine that can be operated with only one system of biomass fuel without using a starting fuel derived from fossil fuels.

  In order to achieve the above object, a gas turbine engine according to the first aspect of the present invention supplies a liquid fuel containing, as a component, a vegetable oil methyl ester obtained by reacting vegetable oil with methanol to a combustor, and the fuel is combusted. Means for heating the fuel temperature in the nozzle at the tip of the spray nozzle to be supplied to a temperature exceeding the pour point of the liquid fuel, and the liquid fuel injected as fine particles from the spray nozzle by the compressed air supplied to the combustor The combustion gas generated after combustion is supplied to a turbine to generate power.

  According to this gas turbine engine, the temperature of the fuel in the nozzle is at the pour point of the liquid fuel at least at the tip of the spray nozzle immediately before the vegetable oil whose viscosity and ignition point are lowered by methyl esterification is further injected into the combustor. By being heated to a temperature exceeding 1, the viscosity is lowered and sprayed in a state of fine particles that can be easily ignited. That is, the diameter of the particles sprayed from the nozzle is reduced, and the particles are easily evaporated and ejected. In addition, the fuel easily evaporates due to the temperature rise itself, and the fuel easily ignites due to the fuel temperature rise itself. Therefore, the combustion reaction by the liquid fuel particles sprayed from the nozzle and the compressed air is likely to proceed, and ignition / start-up with the vegetable oil methyl ester alone becomes possible.

  According to the second aspect of the present invention, the fuel temperature in the nozzle of the liquid fuel is set to a temperature that is higher by 10 ° C. than the pour point of the liquid fuel.

  The invention according to claim 3 uses a liquid fuel in which the volume concentration of the vegetable oil methyl ester in the liquid fuel is 2% or more.

  Further, the invention according to claim 4 uses liquid fuel in which the liquid fuel is all vegetable oil methyl ester.

  Moreover, invention of Claim 5 uses palm methyl ester as vegetable oil methyl ester.

  According to a sixth aspect of the present invention, the fuel supply system for supplying the liquid fuel to the spray nozzle of the combustor includes means for heating the liquid fuel to a temperature exceeding the pour point of the liquid fuel. In this case, even when a liquid fuel containing a vegetable oil methyl ester having a pour point of 0 ° C. or higher as a component, such as palm methyl ester, is not clogged with the fuel supply system.

  In the invention according to claim 7, the temperature at which the liquid fuel is heated is 20 ° C. or higher and 200 ° C. or lower.

  Furthermore, a gas turbine engine according to an eighth aspect of the present invention supplies liquid fuel containing vegetable oil methyl ester as a component to the combustor, and sets the fuel temperature in the nozzle at the tip of the spray nozzle that supplies the fuel to the combustor. A gas turbine engine having means for heating to a temperature exceeding the pour point of the fuel, and combusting liquid fuel with compressed air supplied to the combustor to generate combustion gas; and a combustion gas supplied from the gas turbine engine A startup turbine comprising a driven turbine, a compressor for supplying compressed air to a gas turbine engine, a starter motor or a generator also serving as a starter motor arranged coaxially with the compressor, and a starter power supply Occasionally, the compressor is driven using a power source for start-up, compressed air is supplied to the gas turbine engine, and the tip of the spray nozzle is heated by the heat of the compressed air Unishi to have.

  In this case, at the time of start-up, the starter power supply is used to rotate a motor or a generator that also serves as a motor, thereby rotating the coaxially connected compressor to generate compressed air around the spray nozzle. Since it can supply, the front-end | tip part of a spray nozzle is heated with the heat of compressed air. Therefore, if the liquid fuel is injected after the fuel temperature in the nozzle at the tip of the spray nozzle can be heated to a temperature that exceeds the pour point of the liquid fuel, it can be sprayed with fine particles that are easily ignited.

  According to the first aspect of the present invention, the viscosity and ignition temperature of the vegetable oil fuel are lowered by methyl esterification, and the fuel temperature in the nozzle at the tip of the spray nozzle immediately before injection into the combustor is the pour point of the liquid fuel. Since the particles are heated as described above, the diameter of the particles sprayed from the nozzle is reduced and is easily evaporated, and the fuel is easily evaporated and easily ignited by the temperature rise of the fuel itself.

As a result, the liquid fuel containing vegetable oil methyl ester as a component can be ignited and started, and no other starting fuel is required. In addition, liquid fuel containing vegetable oil methyl ester has a higher calorific value per mass than solid biomass fuels such as wood chips, so that the energy required for combustion is sufficient, and liquid fuel containing vegetable oil methyl ester alone Can be burned with no auxiliary fuel. Therefore, a separate fuel supply device for starting fuel and a fuel supply device for auxiliary fuel are not required, and the control thereof is not required. This factor will not increase. And since the spray characteristic equivalent to light oil is realizable, the spray nozzle for light oil can be used as it is. Furthermore, since it is not necessary to use fossil fuel as the starting fuel, the CO ₂ emission reduction effect corresponding to that amount is enhanced.

  Furthermore, since the spray particle size of the liquid fuel containing vegetable oil methyl ester as a component is reduced and is easily evaporated and mixed with air, the flame becomes closer to a lean premixed flame and the generation of NOx is suppressed.

In addition, liquid fuels containing vegetable oil methyl esters have higher collection and transport efficiency than solid biomass fuels, making it possible to achieve a stable supply of fuel that has been a major obstacle when using biomass fuels and operate. Cost can be reduced. In addition, vegetable oil methyl ester is an inorganic component that causes ash and slag, chlorine that causes dioxins, sodium and potassium that cause corrosion of materials such as turbines, and aromatic carbonization that causes smoke and luminous flames. Since it does not contain hydrogen or cyclic hydrocarbons, it is possible to eliminate any problems caused by them. That is, ash, slag, and dioxin are not discharged, the life of a material such as a turbine can be extended, and NOx and smoke emissions can be suppressed. Furthermore, since it is used as it is as a liquid fuel, it is not necessary to gasify the fuel at a high temperature, and neither generation of tar nor pure water for removing tar is required. Moreover, CO ₂ is emitted during combustion because biomass fuels are those originally due to CO ₂ in the atmosphere, not lead to occurrence of new CO _2, can contribute greatly to reducing emissions of CO _2.

  According to the second aspect of the present invention, since the fuel temperature in the nozzle is set to a temperature that is 10 ° C. or more higher than the pour point, it is possible to realize a stable spray that makes liquid fuel easy to evaporate even when the temperature is low.

  In addition, according to the invention described in claim 3, the fuel in which vegetable oil methyl ester is partially mixed with light oil, which may be distributed as fuel for automobiles in the future, can be used as it is.

In addition, according to the invention of claim 4 in which the liquid fuel is all vegetable oil methyl ester, although it is accompanied by a decrease in calorific value of about 10 to 20% compared to light oil, it requires a separate auxiliary fuel. In addition, there is an extraordinary effect that the emission of CO ₂ , NOx and smoke can be remarkably suppressed as compared with the liquid fuel derived from fossil fuel.

  In addition, according to the invention described in claim 5, since palm methyl ester is used, the problem relating to the stable supply of biomass fuel can be solved. Palm methyl ester has the highest supply stability to Japan and is an inexpensive biomass fuel.

  Moreover, according to invention of Claim 6, it can utilize also by the biomass fuel containing the vegetable oil methyl ester which solidifies and is hard to use when temperature is low. In other words, the liquid fuel or the vegetable oil methyl ester in the liquid fuel does not solidify in the fuel tank, in the middle of the pipe, or in the flow rate control valve, so that the liquid fuel can be stably supplied. In particular, it is possible to use a vegetable oil methyl ester having a pour point close to room temperature, such as a liquid fuel containing a vegetable oil methyl ester having a pour point of 0 ° C. or higher as a component, such as palm methyl ester.

  According to the invention described in claim 7, since the temperature for heating the liquid fuel in the fuel supply system is 20 ° C. or more and 200 ° C. or less, it is possible to stably supply any vegetable oil methyl ester while realizing stable spray combustion. However, an increase in operating cost can be suppressed without increasing heat loss.

  Further, according to the invention described in claim 8, even if the temperature of the combustion chamber is not increased by using the starting fuel, the starting motor is used to rotate the starting motor or the generator that also serves as the starting motor. Since the compressed air can be generated and supplied to the periphery of the spray nozzle, the tip of the spray nozzle is heated by the heat of the compressed air. For this reason, by injecting the liquid fuel itself containing vegetable oil methyl ester as a component into the combustor from the spray nozzle, the liquid fuel is sprayed in a state of being easily evaporated by fine particles and can be easily ignited.

  Hereinafter, the configuration of the present invention will be described in detail based on embodiments shown in the drawings.

  FIG. 1 shows a first embodiment in which the present invention is applied to a gas turbine power generation system and a liquid fuel gas turbine engine used therefor. The gas turbine power generation system of this embodiment includes a gas turbine engine 21 that generates a combustion gas by burning a liquid fuel containing vegetable oil methyl ester as a component, and a turbine that is driven by the combustion gas supplied from the gas turbine engine 21. 9, a compressor 8 for supplying compressed air to the gas turbine engine, a generator 7 arranged coaxially with the compressor 8 and the turbine 9, and a switcher 10 for driving the generator 7 as a motor at startup And a starting power supply 18, and the generated combustion gas is supplied to the turbine 9 to rotate the generator 7 to generate electric power. Although not shown in the figure, the connecting shaft between the compressor 8 and the turbine 9 is provided with a clutch, and can be intermittently connected as necessary.

  Here, the gas turbine engine 21 is provided with means for heating the fuel temperature in the nozzle at the tip of the spray nozzle 3 to a temperature exceeding the pour point of the liquid fuel, and the liquid fuel containing vegetable oil methyl ester as a component is the pour point. It is set as the structure inject | poured in the combustor 6 in the state kept at the temperature over this. The liquid fuel supplied from the fuel tank 1 of the fuel supply system 22 through the pipe 17 and the control valve 2 is burned by compressed air supplied from the air compressor 8 through the swirler 4 to the combustor 6. In this gas turbine power generation system, at the time of startup, the generator 7 is driven as a motor by using the startup power source 18 to drive the compressor 8 connected coaxially, and the compressed air is supplied to the gas turbine engine. The tip of the spray nozzle 3 is supplied and heated by the heat of the compressed air.

As fuel, methyl ester of vegetable oil obtained by esterifying and purifying vegetable oil such as soybean oil, rapeseed oil, palm oil, sunflower oil, peanut oil, cottonseed oil, coconut oil, olive oil, palm kernel oil, corn oil, waste cooking oil, etc. with methanol A liquid fuel containing as a component is used. The chemical formula is shown below.
(Chemical formula 1)
R-COO-CH ₃
R: Linear hydrocarbon As a liquid fuel derived from fossil fuel mixed with vegetable oil methyl ester, light oil is generally mainstream, but other fuels can also be used. Here, the pour point of the fuel obtained by mixing vegetable oil methyl ester and light oil is between the pour point of light oil and the pour point of vegetable oil methyl ester. In the case of cottonseed oil or safflower methyl ester having a low pour point, when mixed with light oil, the pour point rises, and in the case of palm ester or coconut methyl ester having a high pour point, the pour point decreases when mixed with light oil. The main vegetable oil methyl esters having a pour point of 0 ° C. or higher include coconut methyl ester and palm methyl ester. In addition, since the pour point is increased if other vegetable oils are refined to collect polymer components or hydrogenated to methylesterify, such treatment may be performed as necessary.

  The pour point of vegetable oil methyl ester varies from about -50 ° C to 12.5 ° C depending on the type of vegetable oil used as the raw material, and those with pour points lower than -30 ° C are used in winter in cold regions (Hokkaido). Since it is the same as light oil (JIS K 2204 (2004), pour point = −30 ° C. or lower), heating is not necessary. Also, some vegetable oil methyl esters have a slightly pour point lower than 0 ° C., such as rapeseed oil methyl ester (pour point = −7.5 ° C.) and soybean oil methyl ester (pour point = −7.5 ° C.). There are cases where the fuel temperature is above the pour point even if the fuel is not necessarily heated to 20 ° C or higher, including during startup, but it is still more stable atomization when the fuel temperature in the nozzle is higher. It is preferable in order to obtain a spray. On the other hand, in winter and cold regions, the temperature may be lower than 0 ° C., and in such places, fuel containing vegetable oil methyl ester having a pour point of 0 ° C. or higher as a component is solidified and cannot be used. Even in the case of a fuel having a slightly lower pour point than 0 ° C., atomized spray may not be stably obtained. Furthermore, unless the temperature is raised to a certain degree from the pour point, the viscosity does not drop sufficiently, fuel cannot be sprayed stably from the nozzle, spray particles do not atomize, and NOx cannot be lowered. On the other hand, vegetable oil methyl ester as biomass fuel has the highest supply stability to Japan, and the use of inexpensive palm methyl ester is preferable. However, this palm methyl ester has a high pour point of 12.5 ° C., and when the temperature is low, fuel can be stably supplied to the combustor and cannot be sprayed. So, if palm methyl ester is used as a standard and heated to a temperature of at least 20 ° C. in consideration of the safety factor, it can be atomized without clogging liquid fuel containing any kind of vegetable oil methyl ester as a component. It becomes possible to spray.

  In addition to being liquid, the fuel containing vegetable oil methyl ester as a component has the effect of lowering viscosity and flash point by methyl esterifying the vegetable oil, and handling and ignition as a fuel are facilitated. In addition, the fuel collection and transportation efficiency is higher than that of solid biomass fuel, and the calorific value per mass is about 10 to 20% lower than that of light oil, and the calorific value per mass of solid biomass fuel. Therefore, it is possible to burn the fuel alone by spraying it in the form of fine particles that easily evaporate, and it is not necessary to separately prepare a liquid or gaseous fuel derived from fossil fuel for starting. Vegetable oil methyl ester contains almost no inorganic components that cause ash or slag in the fuel. Also, vegetable oil methyl esters, unlike liquid fuels derived from fossil fuels such as light oil, do not contain aromatic hydrocarbons and cyclic hydrocarbons that cause smoke, and contain almost no side chains, double / triple bonds in the molecule. Absent. Further, it contains oxygen atoms that suppress the generation of smoke. Further, the combustion flame becomes closer to a lean premixed combustion flame, and the generation of NOx is suppressed. On the other hand, in light oil, since raw material crude oil contains sulfur, advanced desulfurization treatment using high-temperature, high-pressure and expensive hydrogen is required when refining light oil, but vegetable oil contains almost no sulfur in the raw material. No desulfurization treatment is required. It contains almost no chlorine, which causes dioxins, and sodium, potassium, etc., which causes corrosion of materials such as turbines.

In addition, since vegetable oil methyl ester can be mixed with the liquid fuel derived from fossil fuels, such as light oil, in arbitrary ratios, you may mix and use the liquid fuel derived from a fossil fuel. Currently, in Japan, we are investigating the use of a fuel in which vegetable oil methyl ester is partly mixed with light oil as a fuel for automobiles. Becomes easier. In addition, with regard to diesel oil mixed with vegetable oil methyl ester, which is distributed overseas, the mixing ratio of vegetable oil methyl ester is more than 2%, and the mixing ratio in Japan is expected to be more than 2%. On the other hand, as described above, as the amount of the vegetable oil methyl ester used, that is, the amount added is increased, the effect of reducing the CO ₂ emission amount can be obtained without causing problems when using a liquid fuel derived from fossil fuel. Therefore, the volume concentration of the vegetable oil methyl ester in the liquid fuel is preferably as large as possible, and is at least 2 vol% or more, preferably 100 vol%.

  The spray nozzle 3 is structured so as to be in contact with the compressed air in the casing 5 so that the spray nozzle 3 is heated by the compression heat of the air, and the fuel temperature in the nozzle at the tip of the spray nozzle exceeds the pour point of the liquid fuel. For example, it is provided to be 10 ° C. or higher, more preferably 20 ° C. or higher. Further, a swirler 4 is disposed around the tip of the spray nozzle 3, and is provided so as to heat the tip of the nozzle 3 with the heat of the compressed air when the compressed air is injected into the combustor 6. That is, in the present embodiment, the spray nozzle 3 is brought into contact with the compressed air in the casing 5, and further, the swirler is arranged in direct contact with the tip of the spray nozzle 3, so that the heat of the compressed air is used. By heating the spray nozzle, a means for heating the liquid fuel inside thereof to a temperature exceeding the pour point is configured. The fuel temperature in the nozzle at the tip of the spray nozzle is not strictly required to be higher by 10 ° C. or higher. When heated at least 10 ° C., the diameter of the particles sprayed from the nozzle is reduced. It becomes easy to evaporate. There is also an effect that the fuel easily evaporates due to the temperature rise of the fuel itself. Further, there is an effect that the fuel is easily ignited by the increase in the fuel temperature itself. As a result, the combustion reaction by air is easy to proceed, and it becomes possible to ignite and start with vegetable oil methyl ester alone. In the case of a liquid fuel containing vegetable oil methyl ester as a component, if sprayed simply from a fuel nozzle, the spray particle size increases due to high viscosity, making ignition difficult. In the case of a liquid fuel, if the fuel remains in a liquid state, it cannot react with air and burn, but can react with air and burn in a state where the liquid is evaporated into a gas. Therefore, by increasing the temperature of the liquid fuel at the fuel nozzle portion above the pour point, the diameter of the spray particles is reduced to facilitate evaporation.

  The structure / means for heating the fuel temperature in the nozzle at the tip of the spray nozzle 3 to a temperature exceeding the pour point of the liquid fuel is such that the fuel temperature in the nozzle at least at the tip of the spray nozzle 3 has the pour point of the liquid fuel. There is no particular limitation on the means and structure as long as the temperature can be raised to, for example, 10 ° C. or higher. For example, it may be structured to be heated by the compression heat of the air in the combustor 6 and heat from the combustion flame, or may be structured to be heated by heat conduction from the combustor material such as the combustor 6 or the casing 5 itself. A separate means for heating the fuel may be provided upstream, that is, in the fuel supply system. Further, a heater is wound around a part of the spray nozzle 3, for example, a rear end exposed outside the casing 5, or exhaust from the turbine 9 is introduced around the spray nozzle so as to cover the rear end of the spray nozzle. By forming the space, the rear end of the spray nozzle may be heated and the heat transferred to the front end side of the spray nozzle by heat conduction.

  In addition, the spray particle size can be reduced by heating the fuel temperature in the nozzle to a temperature exceeding the pour point at the tip of the spray nozzle 3. The smaller the spray particle size, the easier the liquid fuel evaporates, and as a result, ignition becomes easier. For this reason, it is not necessary to separately supply liquid fuel or gas fuel for starting at the time of starting. Furthermore, as a result of being easily evaporated, it becomes easy to mix with air, and the combustion flame becomes close to a lean premixed flame. Compared with the diffusion flame, the lean premixed flame has a lower temperature peak in the flame and can suppress thermal NOx generated by the reaction of oxygen and nitrogen in the air at a high temperature. In addition, the viscosity of vegetable oil methyl ester is slightly higher than that of light oil, but by increasing the fuel temperature in the nozzle, it can be made the same viscosity as light oil, and the spray characteristics similar to light oil can be realized, A spray nozzle for light oil can be used as it is, and a stable spray can be realized.

  Here, an example of a structure in which the temperature of the fuel in the nozzle at the tip of the spray nozzle is set to a temperature exceeding the pour point of the liquid fuel, for example, 10 ° C. or more is shown in FIGS. FIG. 2 shows a structure in which the fuel in the spray nozzle 3 is heated with air from a compressor whose temperature has been raised by compression heat. This heating means directly heats the spray nozzle 3 with the heat of the compressed air by introducing the compressed air supplied from the compressor 8 around the spray nozzle 3 in the space between the casing 5 and the combustor wall 11. And a swirler 4 that introduces compressed air from the space between the casing 5 and the combustor wall 11 into the combustor 6 is disposed in direct contact with the periphery of the tip of the spray nozzle 3. It is comprised by making it the structure which transmits the heat | fever of the compressed air which the swirler 4 receives by heat conduction.

  The heating means of the embodiment shown in FIG. 3 introduces an air stream having an increased temperature or a steam stream having an increased temperature around the fuel nozzle 12 separately from the mainstream air for combustion. The fuel is injected from the fuel nozzle 12 into the steam flow to heat the fuel, and then the fuel is atomized from the air atomization atomizing nozzle 13 to inject the fuel into the combustor together with the air current. The atomizing spray nozzle 13 for introducing the air flow or the water vapor flow having an increased temperature around the fuel nozzle 12 has a double tube structure, and the fuel nozzle 12 is disposed in front of the injection port of the atomizing spray nozzle 13. By arranging the injection ports, the space between the two injection ports is provided so as to function as a premixing region of the fuel and the air or water vapor whose temperature has increased. Therefore, in addition to heating through the fuel nozzle 12 by air or water vapor flowing around the fuel nozzle 12, the fuel is efficiently heated in the atomization spray nozzle by being in direct contact with air or water vapor. Furthermore, it is atomized by adding the effect of the air current and sprayed into the combustor in a state where it can be easily ignited.

  The heating means of the embodiment shown in FIG. 4 includes a fuel evaporation pipe 14 inside the combustor 6 of the combustor wall 11. The fuel is injected from the spray nozzle 3 into the fuel evaporation pipe 14 and the temperature rises. Air is also introduced to heat the fuel, to mix the air and fuel, evaporate the fuel, and to form an air-fuel mixture that is then injected into the combustor. A part of the compressed air is introduced into the fuel evaporation pipe 14 along the spray nozzle 3, and the remaining part is directly injected into the combustor 6 through the swirler 4. As a result, the fuel is heated by the air flowing around the spray nozzle 3 through the spray nozzle 3, atomized, and injected into the evaporation pipe 14. In the evaporation pipe 14, the fuel is further heated and evaporated by the heated air introduced from around the spray nozzle 3 and is mixed with the air to be in a premixed gas state. Further, since the outlet of the evaporation pipe 14 is directed to the combustor wall 11, it collides with the compressed air injected from the swirler 4 and is further mixed. Since the evaporation pipe 14 is heated by receiving radiation heat from the inside of the combustor 6, the mixture of atomized fuel and compressed air flowing through the inside of the evaporation pipe 14 is further heated by solid radiation heat. Therefore, an air-fuel mixture of liquid fuel containing vegetable oil methyl ester as a component and compressed air is injected into the combustor in a state where it can be easily ignited.

  According to all the spray nozzle structures of FIGS. 2, 3 and 4 described above, the combustion approaching the lean premixed flame is established. In the case of combustion of liquid fuel, even if fuel and air are supplied through separate paths, liquid fuel follows the path of evaporation → contact / mixing with air → combustion, so it can be mixed from air until combustion. Depending on the progress of mixing, the diffusion flame becomes closer to a lean premixed flame. For example, when it evaporates and burns immediately, mixing with air does not progress and becomes a diffusion flame, but if it does not burn immediately after evaporating, mixing with air proceeds in the meantime, and it is close to a lean premixed flame. Become. For this reason, when fuel and air are supplied completely separately as shown in FIG. 2, it is difficult to make a complete lean premixed flame, but it can still be close to a lean premixed flame. In FIG. 3, since the spray particles of the liquid fuel are sprayed in a state of being mixed with air, if it does not burn immediately even after evaporation, mixing with the air proceeds during that time, and it can be brought close to a lean premixed flame. In the case of the fourth embodiment, it is further brought closer to a lean premixed flame.

  According to the gas turbine engine and the gas turbine power generation system configured as described above, first, at the time of start-up, the generator 7 is rotated as a motor by using the start-up power supply 18, and the compressor 8 connected coaxially is rotated. It can be driven to generate compressed air and supply it around the spray nozzle 3. At this time, the turbine 9 is disconnected because it becomes a load of the power supply 18 for starting. Then, by flowing only the compressed air from the casing 5 into the combustor 6, the spray nozzle 3 is heated by the heat of the compressed air, and the fuel temperature in the nozzle at the tip of the spray nozzle is set to a temperature exceeding the pour point of the liquid fuel. Prepare for heating. Thereafter, if liquid fuel is injected, it can be sprayed with fine particles that are easy to ignite. The vegetable oil whose viscosity and ignition point have been lowered by methyl esterification is further heated to a temperature at which the fuel temperature in the nozzle exceeds the pour point of the liquid fuel at least at the tip of the spray nozzle 3 immediately before being injected into the combustor. By spraying, it is sprayed in a state of fine particles that can be easily ignited with a reduced viscosity. That is, the diameter of the particles sprayed from the nozzle 3 is reduced, and the particles are easily evaporated and ejected. In addition, the fuel easily evaporates due to the temperature rise itself, and the fuel easily ignites due to the fuel temperature rise itself. Since vegetable oil methyl ester has a relatively high calorific value per mass, it can be burned alone with sufficient supply of energy necessary for combustion. Therefore, the combustion reaction by the liquid fuel particles sprayed from the nozzle 3 and the compressed air is likely to proceed, and ignition / startup with the vegetable oil methyl ester alone becomes possible. Therefore, liquid fuel and compressed air are burned in the combustor 6 in a state close to lean premixed combustion, and the combustion gas is taken out and the turbine 9 is driven to rotate the compressor 8 and the generator 7 on the same axis. To generate electricity.

  Next, FIG. 5 shows a second embodiment in which the present invention is applied to a gas turbine power generation system and a gas turbine engine for liquid fuel used therefor. In addition, about the component similar to the above-mentioned 1st Embodiment, the same code | symbol is attached | subjected and the detailed description is abbreviate | omitted.

  This gas turbine engine is suitable when using a liquid fuel containing a vegetable oil methyl ester having a pour point of 0 ° C. or higher, such as palm methyl ester, as a component. Palm methyl ester has the highest supply capacity to Japan among vegetable oils, and is likely to be available stably and inexpensively. However, the pour point is as high as 12.5 ° C., and in the case of the gas turbine engine according to the embodiment of FIG. 1, if the temperature is low, fuel may not be stably supplied to the combustor and sprayed. Therefore, in this gas turbine engine, the temperature of the liquid fuel inside the fuel supply system 22 is higher than the pour point, preferably higher by 10 ° C. than the pour point, more preferably 20 ° C. in consideration of the safety factor. It is provided with a structure / means for maintaining a high temperature. In addition, since it is the same structure as 1st Embodiment except arrange | positioning a heating means to the fuel supply system 22, the description is abbreviate | omitted.

  For example, the heater 15 is provided in the fuel tank 1 to heat the stored liquid fuel, and the heater 16 is provided while the periphery of the pipe 17 is protected by a heat insulating material, thereby heating and keeping the pipe. The liquid fuel flowing inside is heated and supplied to the combustor 6 through the flow control valve 2 and the spray nozzle 3. The heaters 15 and 16 may be electric heaters, or may utilize the heat of the gas turbine engine exhaust gas.

  Here, the heating of the fuel supply system 22 by the heaters 15 and 16 may clog the flow rate control valve and the filter without being completely liquefied when the fuel temperature is just below the pour point. Furthermore, the viscosity is high near the pour point, and a large amount of power is required to supply the fuel. Therefore, it is considered that, if heating is performed at a temperature of at least 10 ° C., preferably 20 ° C. or more, higher than the pour point, these problems can be solved sufficiently and a wasteful amount of heat is not wasted. Liquid fuel containing vegetable oil methyl ester as a component can realize atomization of spray particles as the heating temperature increases. However, if the temperature exceeds 200 ° C, heat loss increases for the contribution to atomization and evaporation of spray particles. Operating costs increase. Therefore, in the fuel supply system 22, the range heated by the means 15 and 16 for heating the liquid fuel to a temperature exceeding the pour point is preferably 20 ° C. or higher and 200 ° C. or lower. However, heating by the heating means 15 and 16 is not limited to 200 ° C. or less. It is also possible to adopt a structure in which the fuel temperature in the nozzle at the tip of the spray nozzle 3 is maintained at 20 ° C. or higher by heating with the heaters 15 and 16.

  In the case of this embodiment, the liquid fuel or the vegetable oil methyl ester in the liquid fuel is solidified and clogged in the fuel tank 1 or in the pipe 17 and further in the flow control valve 2 or the like (collectively referred to as the fuel supply system 22). The fuel supply system is clogged even when using biomass fuel that contains vegetable oil methyl ester that is hard to use when the temperature is low, such as palm methyl ester. In this way, liquid fuel can be stably supplied. In addition, liquid fuels containing vegetable oil methyl ester having a pour point other than palm methyl ester as a component, such as coconut methyl ester (pour point is 10 ° C.), or rapeseed oil methyl ester (pour point = −7.5 ° C.) Even vegetable oil methyl ester with a slightly lower pour point than 0 ° C, such as soybean oil and soybean oil methyl ester (pour point = -7.5 ° C), can stably supply liquid fuel without being affected by a decrease in outside air temperature. Become. Of course, when a liquid fuel containing plant methyl ester having a sufficiently low pour point temperature such that the temperature of the pour point is below 0 ° C. is used, a heating device is used for the fuel tank and piping as in this embodiment. Of course, in the first embodiment, the temperature of the internal fuel at the tip of the fuel supply system 22 and the spray nozzle is maintained at a temperature higher than the pour point of the liquid fuel.

  The above-described embodiment is an example of a preferred embodiment of the present invention, but is not limited thereto, and various modifications can be made without departing from the gist of the present invention. For example, in the present embodiment, the gas turbine power generation system and the gas turbine engine used therefor have been mainly described. However, it goes without saying that the application of the present invention is not particularly limited to this, and can also be applied to an automobile gas turbine engine. It is. In this case, an automobile generator is used as the generator 7 and an automobile battery is used as the start-up power supply 18. Further, a starter motor for an automobile is used as a starting power source coaxially with the compressor 8. And at the time of starting, the starter motor for motor vehicles is driven with the battery for motor vehicles, and the compressor 8 is rotated. Further, in some cases, the spray nozzle may be heated at the time of startup by directly heating the spray nozzle with an electric heater or the like so that the fuel temperature in the nozzle exceeds the pour point of the liquid fuel.

1 is a schematic configuration diagram illustrating a first embodiment of a gas turbine engine and a gas turbine power generation system according to the present invention. It is the schematic which shows one Embodiment of the nozzle structure which comprises the means to heat the fuel temperature in the nozzle of the front-end | tip part of a spray nozzle. It is the schematic which shows other embodiment of the nozzle structure which comprises the means to heat the fuel temperature in the nozzle of the front-end | tip part of a spray nozzle similarly. It is the schematic which shows other embodiment of the nozzle structure which comprises the means to heat the fuel temperature in the nozzle of the front-end | tip part of a spray nozzle similarly. It is a schematic block diagram which shows 2nd Embodiment of the gas turbine engine and gas turbine electric power generation system concerning this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fuel tank 2 Flow control valve 3 Spray nozzle 4 Swirler 5 Casing 6 Combustor 7 Generator 8 Air compressor 9 Turbine 10 Switch 11 Combustor wall 12 Fuel nozzle 13 Air atomization spray nozzle 14 Fuel evaporation pipe 15 Heater 16 Heater 17 Pipe 18 Start-up power supply 21 Gas turbine engine 22 Fuel supply system

Claims (8)

Means for supplying liquid fuel containing vegetable oil methyl ester as a component to the combustor and heating the fuel temperature in the nozzle at the tip of the spray nozzle for supplying fuel to the combustor to a temperature exceeding the pour point of the liquid fuel A gas turbine engine that burns the liquid fuel injected as fine particles from the spray nozzle by compressed air supplied to the combustor and supplies the generated combustion gas to a turbine to generate power. 2. The gas turbine engine according to claim 1, wherein the fuel temperature in the nozzle is higher by 10 ° C. than the pour point. The gas turbine engine according to claim 1 or 2, wherein the volume concentration of vegetable oil methyl ester in the liquid fuel is 2% or more. The gas turbine engine according to claim 1 or 2, wherein the liquid fuel is all vegetable oil methyl ester. The gas turbine engine according to any one of claims 1 to 4, wherein the vegetable oil methyl ester is palm methyl ester. The fuel supply system for supplying the liquid fuel to the spray nozzle of the combustor is provided with means for heating the liquid fuel to a temperature exceeding the pour point of the liquid fuel. The gas turbine engine described in 1. The gas turbine engine according to claim 6, wherein a temperature at which the liquid fuel is heated is 20 ° C. or higher and 200 ° C. or lower. Means for supplying liquid fuel containing vegetable oil methyl ester as a component to the combustor and heating the fuel temperature in the nozzle at the tip of the spray nozzle for supplying fuel to the combustor to a temperature exceeding the pour point of the liquid fuel A gas turbine engine that generates combustion gas by burning the liquid fuel with compressed air supplied to a combustor, a turbine that is driven by the combustion gas supplied from the gas turbine engine, and a compressor that compresses the gas turbine engine A compressor that supplies air; a starter motor that is arranged coaxially with the compressor or a generator that also serves as a starter motor; and a starter power source, and the starter power source is used for the compression when starting A gas turbine for driving a machine, supplying compressed air to the gas turbine engine, and heating the tip of the spray nozzle with the heat of the compressed air Engine.

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