JP2013119795A - External combustion engine generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an external combustion engine generator which is driven by combustion gas of relatively low temperature by biomass fuel with a simple structure and has excellent heat efficiency.SOLUTION: The external combustion engine generator is provided with: an external engine driven by using volumetric expansion by heat-expanding compressed air by heating; an air compressor constituted of a casing and a turbine housed therein; an air heating unit heating and expanding air supplied from the air compressor; a rotary driving unit constituted of the casing and turbine housed therein and using the heated expanded air flowing from the air heating unit as an energy source; and a heat source used for heating air at the air heating unit. Rotary shafts of the air compressor and rotary driving unit are coaxially formed, and a generation electric motor is provided to the rotary shaft end of the compressor side to start an engine by the generation electric motor when starting the engine, to generate power by the generation electric motor after driving the external combustion engine.

Description

The present invention relates to an external combustion engine having excellent thermal efficiency and a power generation apparatus using the external combustion engine.

As the external combustion engine, various combustibles such as biomass, geothermal heat, solar heat, and other various heat sources can be used. As this external combustion engine, a so-called Stirling engine is well known. A Stirling engine uses the thermal expansion and contraction of gas, so the amount required is larger than the amount of work, and the size of the Stirling engine needs to be increased for output. For this reason, measures such as filling helium gas at a high pressure instead of air at atmospheric pressure as the working gas have been taken today, but the following new problems have also occurred.
1 The mechanical rotation mechanism becomes complicated.
2 A complicated sealing mechanism is required to use expensive high-pressure helium gas, but the gas leaks in a short period of time, and an increase in total cost cannot be avoided.

The following is a technical document related to the present application.
JP 2009-156233 A JP 2009-92007 A JP 2009-127476 A JP 2009-92079 A No. 2004-101983

The present inventor previously disclosed novel external combustion engines in Japanese Patent Application Nos. 2010-94632, 2010-275476, 2011-86964, and the like in order to overcome the above-mentioned difficulties. The proposed external combustion engines are lightweight and compact, and have a simple structure that is reliable, low in manufacturing cost, and excellent in thermal efficiency. However, the structural manufacturing cost is high and the efficiency of power generation is designed. There were problems such as lower than the value and lack of driving stability.
The object of the present invention is to realize a technology related to an external combustion engine that is more excellent in thermal efficiency than the invention according to the above application, is low in manufacturing cost, and is easy to operate stably.

The present invention relates to an external combustion engine power generation apparatus including an external combustion engine that heats and compresses heated compressed air and drives the volume using the volume expansion, and includes an air compressor including a casing and a turbine housed in the casing. An air heating unit that heats and expands the air supplied from the air compressor, and a rotary drive unit that includes a casing and a turbine housed in the casing and uses heated and expanded air flowing from the air heating unit as an energy source. A heat source used for air heating in the air heating unit, and the rotary shaft of the air compressor and the rotary drive unit is formed coaxially, and a generator motor is provided at the end of the rotary shaft on the compressor side The external combustion engine generator is configured to start the external combustion engine by rotating the rotating shaft with a generator motor when the engine is started, and to generate power with the generator motor after the external combustion engine is driven. , It is intended to solve the conventional problems described above.

Further, in the external combustion engine power generation device described in paragraph 0005 above, a water supply device is provided for adding water to the air flowing into the air compressor, and steam is generated by heating in the air heating unit to thermally expand the compressed air. May be configured to increase rate.

Further, in the external combustion engine power generator according to Paragraph 0005 or 0006, the air heating unit is formed by a multi-layered housing, each housing is connected to each other, and the uppermost housing is the air compression unit. In some cases, the lowermost casing is connected to the rotary drive unit, and the rotary drive unit is operated by the heated and volume-expanded air.

Still further, in the external combustion engine power generator according to any one of paragraphs 0005 to 0007, a plurality of gas flow paths that penetrate through the multistage laminated casing that constitutes the air heating unit are provided, and the heated gas from the heat source is circulated. The air from the air compressor which distribute | circulates each housing | casing may be heated, this may be thermally expanded, and it may become the structure which sends the volume expanded air to a rotation drive part.

Further, in the external combustion engine power generator according to any one of paragraphs 0005 to 0008, the heat source may be biomass fuel, and the air heating unit may be installed inside the biomass fuel furnace.

Furthermore, in the external combustion engine power generation device according to paragraph 0009, the air that is supplied from the air heating unit to the rotation drive unit and used for turbine rotation is blown again into the biomass fuel furnace and used as an oxidant for combustion. There are things to do.

  In a conventional thermal power plant that uses petroleum as fuel, after using combustion energy for power generation, exhaust gas of about 600 degrees Celsius is exhausted from the chimney to the atmosphere. That is, the energy of the exhaust gas is exhausted without being effectively used. The present invention is characterized in that a low-temperature combustion gas thermal power that does not have the explosive combustion power unique to biomass fuel can be used. Therefore, even from the low-temperature exhaust gas of about 600 degrees Celsius as described above, It is a new external combustion engine that can operate the engine and use its output for power generation, etc., and is a device suitable for fuel such as biomass fuel that cannot produce high-pressure steam.

The present invention can be converted into a mechanical output with high efficiency by using biomass combustion gas that can only be expected to have a low temperature (1000 degrees Celsius or less) combustion temperature or the low temperature exhaust gas as described above.
In other words, it is possible to use the heat of exhaust gas after being used for heating a power plant, a coke oven, a converter, etc., which uses oil or coal as a heat source, or for power generation. The heat of the exhaust gas is about 600 degrees Celsius, and all of the heat is conventionally discarded as exhaust gas. Such a large amount of energy loss can be eliminated by introducing the present invention. The amount of exhaust gas heat that can be recovered is said to be an enormous amount that does not fall below 10% of the total consumption of oil and coal, but the present invention is an exhaust gas of about 600 degrees Celsius that was economically difficult to use. It can be used effectively by converting the amount of heat it has into mechanical output with high efficiency.

  The gist of the present invention is to ripen and expand air, which is originally a gas, and obtain a mechanical output with the expansion gain to drive a generator engine or the like. The temperature for ripening air and bringing its volume up to 3 times the volume may be 819 degrees Centigrade, and the calorie required is about 200 kcl per square meter of air. If it is a combustion gas in this temperature range, it can be said that there is no problem because it is a combustion temperature that can be produced by any kind of grass, tree, bark, or leaf if it is a slightly dry biomass fuel.

By the way, the reason why the biomass fuel cannot be burned at a high temperature of 1200 ° C. or higher will be explained here. In the biomass fuel, incinerated ash containing a large amount of phosphoric acid component is present at about 1% or less by weight. And if it burns above 1200 degrees Celsius, this ash will melt and flow out. And it has the property of adhering to the part below that temperature and solidifying. For this reason, the boiler tube body, the furnace body, the flue, etc. break down and their functions are lost, so that high temperature combustion cannot be performed.
For this reason, biomass fuel has a low utility value and has become the worst fuel for productivity and has a history of being replaced by fossil fuels. Although it is once again seen as a measure against global warming and as a sustainable recyclable energy, there is no suitable engine for this fuel, and in this state, it is an invaluable energy that can be buried again.
The present invention proposes again a technique that enables efficient use of biomass energy, which has been difficult to use in the past.

In short, in the present invention, combustion is performed at a low temperature (less than 1200 degrees Celsius) and a combustion gas of about 800 degrees Celsius to 1000 degrees Celsius is obtained, and air is used to heat the gas, thereby high thermoelectric conversion efficiency. It is possible to create an institution.
For this purpose, the necessary calories that reach the operating range are less than anything else. Incidentally, at least 900 kcl is necessary to obtain 3 cubic meters of vapor <gas>, but the force trolley required to heat the air to 3 cubic meters is 200 kcl.

The present invention proposes a device for adding a small amount of water mist as shown in the above-mentioned embodiment, but in order to efficiently operate a high-temperature small gas turbine blade that has been developed at present, a gas of at least a four times volume increase or more is proposed. The change (volume multiplication) shows the highest thermoelectric conversion efficiency, and the thermoelectric conversion efficiency is well over about 4 times that of existing state-of-the-art biomass power generation equipment.
In addition, as in the embodiment, no technical obstacles or barriers for enlarging this have been found at the present time, so it is possible to produce a giant device immediately.

Embodiments will be described with reference to the drawings. FIG. 1 is an overall configuration diagram of an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes an external combustion engine power generator including an external combustion engine that is driven by thermal expansion by heating compressed air and using its volume expansion. 2 is an air compressor, and the air compressor 2 includes a casing 21 and a turbine 22 accommodated therein. An air heating unit 3 heats and expands the air supplied from the air compressor 2.

Reference numeral 4 denotes a rotary drive unit that uses heated and expanded air flowing from the air heating unit 3 as an energy source, and includes a turbine 41 and a casing 42 in which the turbine 41 is housed.
In this embodiment, biomass fuel is used as a heat source, that is, a heating source of the air heating unit 3. That is, as shown in the figure, the air heating unit 3 is sent from the air compressor 2 to the air heating unit 3 by combustion of biomass fuel such as wood chips provided in the biomass combustion furnace 5 and supplied from the biomass chip tank 6. The low-temperature and high-pressure air flowing through the inside is heated.

The air compressor 2 and the rotation drive unit 4 are coaxially connected by a rotation shaft 7.
A high-speed and high-frequency (1000 HZ) generator motor 8 is provided at the end of the rotary shaft on the air compressor 2 side, and when the engine is started, the rotary shaft 7 is rotated by the motor function of the generator motor 8 so that the external combustion engine is After starting and driving the external combustion engine, power is generated by the power generation function of the generator motor 8.

Reference numeral 9 denotes an air filter provided at the air suction port of the air compressor 2, and fresh low-temperature air is sucked through the air filter 9, and water is supplied to the air suction port. The container 10 is provided and has a structure in which an appropriate amount of water droplets are sucked simultaneously with the air, and steam is generated by heating in the air heating unit 3 to increase the thermal expansion coefficient of the compressed air. . Such addition of water is to generate steam and promote the volume expansion of air when the volume expansion rate of air is low.
In the embodiment of FIG. 1, the used lean steam air that has been expanded by driving through the turbine 41 of the rotary drive unit 4 {a little water mist mixed therein is vaporized and changed into steam} is still at a high temperature {Celsius It is about 300 degrees} and air containing high concentration oxygen, so it is directly blown again into the biomass combustion furnace 5 and used as an oxidant for combustion.

  FIG. 2 is a partial cross-sectional view showing a related configuration of the air heating unit 3 in the biomass fuel furnace 5 and the combustion gas flow path 11 for heating the air heating unit 3. The air heating unit 3 is formed of casings 31 that are stacked in multiple stages. The casings 31 are connected to each other, and the uppermost casing 31 communicates with the air compressor 2 through the pipe 12. The body 31 is connected to the rotation drive unit 4 by a pipe 13. By combustion of the biomass fuel, the combustion gas heats the compressed air flowing through the flow path 11 from below in the furnace and flows through the air heating unit 3, and when water is added to the air, it is vaporized. It goes up and dissipates into the atmosphere.

Combustion gas that heats the uppermost casing 31) flows from the lower stage while heating the multistage casing 31, so that the corresponding heat is deprived at each stage and the temperature when reaching the uppermost stage is about 250 degrees Celsius. Degree. The temperature difference between the temperature exchange gases in this stage is preferably set to about 200 degrees Celsius. Therefore, the next stage is about 850 degrees Celsius at 150 degrees and 350 degrees, whereas the gas temperature inside the air heating unit 3 is 1 degree Celsius near the outlet.
0 degrees or less.

In this embodiment, the air in the lowermost casing 31 below the furnace 5 is heated to 850 degrees Celsius. Then, the volume of the air is about 3.11 times larger, but this air is originally compressed by the air compressor 2 and is about 1.8 atm. Therefore, 850 / 1.8 = only 472.2 degrees Celsius. That is, 1.8 atm air expands only 1.7 times after heating. Of course, since the heating temperature zone is 850 degrees Celsius, it can be said that the temperature is low, and the amount of heat required for the heating expansion is about 10% compared to the amount of heat of vaporization of water, but the efficiency of the turbine blade of the rotary drive unit 4 that extracts the force is At about 1.7 times, the negative output of the compressor cannot be covered.
Therefore, a small amount of water mist is mixed and vaporized at the same time as the air temperature to make up the volume. When this mist ratio is large, the thermal efficiency is lowered as in the conventional steam engine, but it cannot be recovered again and used as combustion air for biomass chips. For this reason, at most about 30% of steam and heated and expanded air are ideal values. This is because a heat expansion growth rate (actual high-temperature turbine blade passage gas volume) can be secured from 2.7 to 3.1 times.
That is, the turbine 41 of the rotary drive unit 4 is rotated with the force of 3, and the non-output of the coaxial air compressor 2 is subtracted to generate power with the remaining force of 1. This is also the gist of the present invention.

  FIG. 3 shows a flow path 11 of combustion gas that heats air from the casing 31 that is stacked in multiple stages to form the air heating unit 3 and the air compressor 2 that passes through the casing 31 and flows through the casing 31. FIG. 3 is a partially cutaway perspective view showing the related configuration of FIG. 1. In the figure, reference numeral 31 denotes a housing formed of a heat-resistant steel plate, and has a flange F for connection on the side surface. As shown in the figure, a large number of combustion gas passages 11 are installed through the casing 31 in the vertical direction. The combustion gas exchanges heat in the furnace 5 while passing through the outside of the casing 31 and also passes through the flow path 11 to efficiently exchange heat with the air in the casing 31 from above to below the furnace. After moving to and exchanging heat, it is dissipated in the air.

  4 is a partially cutaway plan view of the casing 31 shown in FIG. The air flowing in from the one flange F as the entrance as indicated by an arrow is guided by the guide plate G and flows through the inside of the housing 31 to the other flange F as the exit. During this time, the circulating air is heated by the combustion gas passing through the flow path 11 and the combustion gas flowing along the outside of the casing 31.

In order to operate the external combustion engine power generator 1 shown in FIG. 1, firstly, the biomass chip is burned and heating of the furnace 5 is started, and the entire biomass combustion furnace 5 is filled with the combustion gas and the air heating unit 2 is heated to heat the air. When the part 2, the biomass combustion furnace 5 and the like are warmed, the motor generator 8 is connected to a power source battery (sez shown in the figure) as a motor, and the rotary shaft 7 is started and rotated.

The rotational speed of the rotary shaft 7 and the like is increased, and the low temperature air pressure is increased by the compressor 2 and sent to the air heating unit 3. Since the air compressor 2 is connected to the uppermost casing 31 of the air heating unit 3 by the pipe 12, it enters the uppermost casing 31 and starts heating. The heated biomass flame gas at this stage passes through the air heating unit 3 constituted by the multilayer casing 31 unlike the lowermost casing 31 in direct contact with the flame, and gives thermal energy to the casing 31 at each stage. Therefore, the gas temperature was the coldest, and in this example, after passing through the uppermost casing 31, the temperature became about 250 degrees Celsius and was released into the atmosphere. The temperature difference between the gases in the first stage from the top is therefore a temperature difference of about 200 degrees Celsius with the low temperature mist mixed air heated. The second stage is almost the same temperature difference. The temperature difference in the lowermost stage is almost the same temperature difference. However, since the temperature difference in the lowermost casing 31 can be 300 to 400 degrees Celsius within a short time depending on the combustion state in the biomass combustion furnace 5, it is desirable that the casing 31 is composed of an aged steel plate. .

At present, this type of practical prior art includes steam turbine power generation and the latest steam screw rotor power generation equipment. Of these, steam turbine power generation is the most popular device and has the highest conversion efficiency. This latest single machine has a thermoelectric conversion efficiency of about 37% and a working pressure of 22 MPS. The required furnace temperature does not fall below 1800 degrees Celsius. This means that it can be made at a low temperature (100 degrees Celsius) until steam is generated, but then a high temperature gas of 1700 degrees Celsius or higher is inevitably required for high pressure. This is nothing but the pressure of the steam that can be produced at low temperatures. This is because the output of the external combustion engine is directly proportional to the steam pressure used as described above. As described above, in the present invention, such a high temperature condition is not necessary. An output can be obtained efficiently even at a relatively low temperature by burning biomass fuel. In addition, the external combustion engine according to the present invention can be driven also by the exhaust at a relatively low temperature (approximately 600 degrees Celsius) that has been discarded until now.
Also, exhaust heat that does not reach 600 degrees Celsius can be effectively utilized by being introduced into the biomass combustion furnace.

It is a whole block diagram of one Example of this invention. FIG. 3 is a partial cross-sectional view showing a related configuration of the air heating unit 3 in the biomass fuel furnace 5 and a combustion gas flow path 11 for heating the air heating unit 3. A related configuration of the casing 31 that is stacked in multiple stages to form the air heating unit 3 and the combustion gas flow path 11 that heats air from the air compressor 2 that passes through the casing 31 and circulates through the casing 31. It is a partially cutaway perspective view shown. FIG. 4 is a partially cutaway plan view of a housing 31 shown in FIG. 3.

1. . . . . . . . . . . External combustion engine power generator 2. . . . . . . . . . . Air compressor 21. . . . . . . . . . . Turbine 22. . . . . . . . . . . Casing 3. . . . . . . . . . . Air heating unit 31. . . . . . . . . . . Housing 4. . . . . . . . . . . Rotation drive unit 41. . . . . . . . . . . Turbine 42. . . . . . . . . . . Casing 5. . . . . . . . . . . 5. Biomass combustion furnace . . . . . . . . . . 6. Biomass chip tank . . . . . . . . . . Rotation axis 8. . . . . . . . . . Generator motor 9. . . . . . . . . . . Filter 10. . . . . . . . . . . Water supply 11. . . . . . . . . . . Combustion gas flow path . . . . . . . . . . Guide plate CH. . . . . . . . . . . Wood chips

Claims (6)

An external combustion engine power generator comprising an external combustion engine that heats and compresses and heats compressed air to drive using the volume expansion, and includes an air compressor including a casing and a turbine housed therein, and the air An air heating unit that heats and expands the air supplied from the compressor, a rotary drive unit that includes a casing and a turbine housed in the casing, and that uses heated and expanded air flowing from the air heating unit as an energy source, and an air heating unit A heat source used for air heating in the air compressor, and the rotary shaft of the air compressor and the rotary drive unit is formed coaxially, and a generator motor is provided at the end of the rotary shaft on the compressor side to start the engine An external combustion engine power generator characterized in that a rotating shaft is rotated by a generator motor to start an external combustion engine, and after the external combustion engine is driven, power is generated by the generator motor. The external combustion engine power generator according to claim 1, further comprising a water feeder for adding water to the air flowing into the air compressor, and generating steam by heating in the air heating unit to increase a thermal expansion coefficient of the compressed air. An external combustion engine power generator characterized in that it is enhanced. 3. The external combustion engine power generator according to claim 1, wherein the air heating unit is formed of a multi-layered housing, each housing is connected, and the uppermost housing is connected to the air compressor. An external combustion engine power generator characterized in that the lowermost casing is connected to the rotation drive unit. The external combustion engine power generator according to any one of claims 1 to 3, wherein a plurality of gas flow paths are provided through the multi-layered housings constituting the air heating unit, and a heating gas from a heat source is circulated to each housing. An external combustion engine power generator characterized by heating air from an air compressor that circulates through the body, thermally expanding the air, and supplying the volume-expanded air to a rotary drive unit. 5. The external combustion engine power generator according to claim 1, wherein the heat source is biomass fuel, and the air heating unit is installed inside a biomass fuel furnace. 6. 6. The external combustion engine power generator according to claim 5, wherein the air fed from the air heating unit to the rotary drive unit and used for turbine rotation is blown again into the biomass fuel furnace and used as an oxidizing agent for combustion. An external combustion engine power generator characterized by that.

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