Title:
GASIFIED FUEL BURNER FOR BURNING A LIQUID FUEL AND WATER IN A GASEOUS MIXTURE
United States Patent 3844705


Abstract:
A diffuser-vaporizer is rotatably mounted in a combustion cylinder and formed with an opening which is disposed in spaced juxtaposed relationship to an opening formed substantially in the central portion of a gas chamber defined in the combustion cylinder. There is formed, between the opening in the diffuser-vaporizer and the opening in the gas chamber, a fuel scattering clearance large enough for a liquid fuel to move therethrough and scatter in the combustion cylinder in atomized particles to sustain combustion of the liquid fuel. A frusto-conical blast supply member extends through the gas chamber into the diffuser-vaporizer to supply a stream of air under pressure to the diffuser-vaporizer and then to the gas chamber. A liquid fuel and water are supplied to the diffuser-vaporizer to vaporize quickly on the inner surface of the diffuser-vaporizer. A combustion plate is provided at the periphery of the gas chamber for ejecting therethrough a mixture of gasified fuel and steam together with the stream of air supplied under pressure through the blast supply member to carry out combustion of the gasified fuel. Water may be vaporized separately from the liquid fuel in a steam generating annular chamber provided at the end of a flame ejecting opening of the combustion cylinder. The superheated steam produced is supplied through a steam line to the diffuser-vaporizer where it is mixed with the gasified fuel together with the stream of air supplied under pressure. Means may be provided for converting the stream of air supplied under pressure through the blast supply member into a hot blast and mixing such hot blast with the mixture of gasified fuel and superheated steam to increase the degree of efficiency with which combustion of the gasified fuel is carried out.



Inventors:
MIYAHARA K
Application Number:
05/410757
Publication Date:
10/29/1974
Filing Date:
10/29/1973
Assignee:
DOWA KK,JA
Primary Class:
Other Classes:
239/214.17, 239/214.25, 431/190, 431/210, 431/242
International Classes:
F23D11/04; (IPC1-7): F23D11/04
Field of Search:
431/190,168,162,210,242,243 239
View Patent Images:
US Patent References:
3640673LIQUID FUEL BURNER1972-02-08Okamoto et al.
2381803Oil burner1945-08-07Breault
1699067Rotary burner1929-01-15Holmgren
1671340Liquid-fuel burner1928-05-29Bird



Primary Examiner:
Favors, Edward G.
Attorney, Agent or Firm:
Hill, Gross, Simpson, Van Santen, Steadman, Chiara & Simpson
Claims:
What I claim is

1. A gasified fuel burner adapted to convert a liquid fuel and water into a mixture of a gasified fuel and steam for combustion of the fuel in gasified state, comprising a combustion cylinder, a gas chamber defined in said combustion cylinder and formed with an opening substantially in its central portion, a diffuser-vaporizer rotatably mounted in said combustion cylinder and formed with an opening disposed in spaced juxtaposed relationship to said opening in said gas chamber, with a fuel scattering clearance of a size large enough for the liquid fuel to move therethrough and scatter in the combustion cylinder in atomized particles formed between the opening in the diffuser-vaporizer and the opening in the gas chamber to sustain combustion of the liquid fuel, a frusto-conical blast supply member extending through the gas chamber into the diffuser-vaporizer to supply a stream of air under pressure to the diffuser-vaporizer and then to the gas chamber, a steam generating annular chamber provided at the end of a flame ejecting opening of the combustion cylinder for heating supplied water by the heat produced by combustion of the fuel in liquid state and generating superheated steam therein, a steam line connected at one end to said steam generating annular chamber and opening at the other end in said frusto-conical blast supply member so that the superheated steam produced in said steam generating annular chamber is mixed with the gasified fuel produced in said diffuser-vaporizer together with the stream of air supplied under pressure through the blast supply member, and a combustion plate provided at the periphery of the gas chamber for ejecting therethrough a mixture of gasified fuel and superheated steam together with the stream of air supplied under pressure through the blast supply member whereby combustion of the gasified fuel can be carried out satisfactorily.

2. A gasified fuel burner adapted to convert a liquid fuel and water into a mixture of a gasified fuel and steam for combustion of the fuel in gasified state, comprising a combustion cylinder, a gas chamber defined in said combustion cylinder and formed with an opening substantially in its central portion, a diffuser-vaporizer rotatably mounted in said combustion cylinder and formed with an opening disposed in spaced juxtaposed relationship to said opening in said gas chamber, with a fuel scattering clearance of a size large enough for the liquid fuel to move therethrough and scatter in the combustion cylinder in atomized particles formed between the opening in the diffuser-vaporizer and the opening in the gas chamber to sustain combustion of the liquid fuel, a frusto-conical blast supply member extending through the gas chamber into the diffuser-vaporizer to supply a stream of air under pressure to the diffuser-vaporizer and then to the gas chamber a steam generating annular chamber provided at the end of a flame ejecting opening of the combustion cylinder for heating supplied water by the heat produced by combustion of the fuel in liquid state and generating superheated steam therein, a hot blast producing annular chamber provided outside said steam generating annular chamber, a steam line connected at one end to said steam generating annular chamber and opening at the other end in said frusto-conical blast supply member, and a hot blast duct connected at one end to said hot blast producing annular chamber and opening at the other end in said frusto-conical blast supply member, said steam line opening at the other end in said hot blast duct so that the superheated steam generated in said steam generating annular chamber is ejected into said hot blast producing annular chamber and mixed with the gasified fuel produced in said diffuser-vaporizer while being ejected through said combustion plate whereby combustion of the gasified fuel can be carried out satisfactorily.

3. A gasified fuel burner adapted to convert a liquid fuel and water into a mixture of a gasified fuel and steam for combustion of the fuel in gasified state, comprising a combustion cylinder, a gas chamber defined in said combustion cylinder and formed with an opening substantially in its central portion, a diffuser-vaporizer rotatably mounted in said combustion cylinder and formed with an opening disposed in spaced juxtaposed relationship to said opening in said gas chamber, with a fuel scattering clearance of a size large enough for liquid fuel to move therethrough and scatter in the combustion cylinder in atomized particles formed between the opening in the diffuser-vaporizer and the opening in the gas chamber to sustain combustion of the liquid fuel, a frusto-conical blast supply member extending through the gas chamber into the diffuser-vaporizer to supply a stream of air under pressure to the diffuser-vaporizer and then to the gas chamber, a liquid fuel supply line and a water supply line opening on the inner surface of the diffuser-vaporizer to supply the liquid fuel and water to the diffuser-vaporizer and cause the same to vaporize quickly, and a combustion passage provided at the periphery of the gas chamber and fluidly connected to said diffuser-vaporizer for ejecting at the periphery of the gas chamber a mixture of gasified fuel and steam together with the stream of air supplied under pressure through the blast supply member whereby combustion of the gasified fuel can be carried out satisfactorily.

Description:
This invention relates to burners, and more particularly it is concerned with a gasified fuel burner adapted to vaporize a liquid fuel and water and cause a mixture of a gasified fuel and steam to burn in gaseous state.

The outstanding characteristic of the invention is that a liquid fuel, particularly kerosene, and water are vaporized by precombustion and heating of the fuel in liquid form to produce a gasified fuel and generate steam which gasified fuel and steam are thoroughly mixed together and ejected through a combustion plate as a mixture of gasified fuel and steam in atomized particules for combustion of the gasified fuel.

Heretofore, in gasified fuel burners of the prior art wherein a liquid fuel is vaporized and burned without producing noise and odor, the supplied liquid fuel is vaporized in most cases by suitable means to produce a gasified fuel which is mixed with a stream of air supplied under pressure before being ejected for combustion. Thus, although the gasified fuel burners of the type described offer an advantage in that combustion takes place quietly without producing noise as is the case with burners adapted to burn a fuel in liquid state and without producing odor, they do not lend themselves to economizing on fuel consumption, with only 20 to 30 percent of the fuel being saved by vaporization combustion carried out by means of conventional gasified fuel burners as compared with the combustion of a fuel in liquid state.

Accordingly, a principal object of the invention is to provide a gasified fuel burner wherein a liquid fuel and water are vaporized into gaseous state and mixed together while they vaporize, and a mixture of a gasified fuel and steam thus produced is ejected for combustion with a high degree of efficiency so that fuel consumption can be greatly reduced.

Another object of the invention is to provide a gasified fuel burner wherein a liquid fuel is first burned in liquid state and the heat produced by combustion of the fuel in liquid state is utilized for expedition vaporization of the liquid fuel and water, and a mixture of a gasified fuel and steam produced by the aforementioned precombustion and heating of the fuel in liquid state is further mixed with a stream of air supplied under pressure before the mixture is automatically ejected through the combustion plate for combustion.

A still another object of the invention is to provide a gasified fuel burner wherein there are separately provided a chamber in which a liquid fuel is converted into a gasified fuel by precombustion and heating of the liquid fuel in liquid state and a chamber in which water is heated to generate superheated steam, with a gasified fuel and super heated steam being thoroughly mixed together and ejected through the combustion plate for combustion while the volume of the gases as a whole is increased.

A further object of the invention is to provide a gasified fuel burner wherein the superheated steam generated by the heat produced by precombustion of the liquid fuel in liquid state is injected into a hot blast which is produced by heating a stream of air under pressure or blast by the heat produced by precombustion of the liquid fuel in liquid state, whereby combustion of a gasified fuel can take place satisfactorily with a high degree of efficiency.

According to the invention, there is provided a gasified fuel burner wherein a diffuser-vaporizer is rotatably mounted in a combustion cylinder and formed with an opening which is disposed in spaced juxtaposed relationship to an opening formed substantially in the central portion of the gas chamber, with a fuel scattering clearance of a size large enough for the liquid fuel to move therethrough and scatter in the combustion cylinder in atomized particles being formed between the opening in the gas chamber and the opening in the diffuser-vaporizer to sustain combustion of the fuel in liquid state; a frustoconical blast supply member extends through the gas chamber into the diffuser-vaporizer to supply a stream of air under pressure to the diffuser-vaporizer and then to the gas chamber; a liquid fuel supply line and a water supply line opening on the inner surface of the diffuser-vaporizer to supply the liquid fuel and water to obtain quick vaporization thereof; and a combustion plate is provided at the periphery of the gas chamber for ejecting therethrough a mixture of a gasified fuel and steam together with the stream of air supplied under pressure through the blast supply member so as to effect combustion of the gasified fuel with a high degree of efficiency.

According to the invention, there is provided in the gasified fuel burner of the type described, means for vaporizing the water separately from the liquid fuel comprising a steam generating annular chamber disposed at the end of a flame ejecting opening of the combustion cylinder for obtaining quick vaporization of water to generate superheated steam by the heat produced by precombustion of the liquid fuel in liquid state on the inner surface of the diffuser-vaporizer while the liquid fuel is vaporized on the inner surface of the diffuser-vaporizer, and a steam line connected at one end to the steam generating annular chamber and an opening at the other end in the frusto-conical blast supply member for introducing the superheated steam therethrough into the diffuser-vaporizer together with the stream of air supplied under pressure through the blast supply member.

According to the invention, there is also provided, in the gasified fuel burner of the type described, means for producing a hot blast by heating a stream of air under pressure or blast by the heat produced by precombustion of the fuel in liquid state, so that the superheated steam can be injected into the hot blast to obtain improved mixing of not only the superheated steam and hot blast but also of the gasified fuel and superheated steam, such means comprising a hot blast producing annular chamber disposed outside the steam generating annular chamber, a blast duct connected at one end to the hot blast producing annular chamber to supply a cool blast thereto, and a hot blast duct connected at one end to the hot blast producing annular chamber and opening at the other end in the blast supply member, with the steam line connected at one end to the steam generating annular chamber and opening at the other end in the hot blast duct, whereby the superheated steam generated in the steam generating annular chamber can be injected into a hot blast produced in the hot blast producing annular chamber while the superheated steam is mixed with the gasified fuel produced on the inner surface of the diffuser-vaporizer to produce a mixture of gasified fuel and superheated steam for combustion through the combustion plate.

Additional and other objects and features of the invention will become evident from the description set forth hereinafter when considered in conjunction with the accompanying drawings, in which:

FIG. 1 and FIG. 2 illustrate an embodiment of the invention in which a liquid fuel and water are vaporized in the same vaporizing chamber, FIG. 1 being a vertical sectional front view of the burner with certain parts being cut out and FIG. 2 being a side view thereof;

FIG. 3 to FIG. 6 illustrate another embodiment in which a liquid fuel and water are vaporized in separate chambers into gaseous state and mixed together later for combustion, FIG. 3 being a vertical sectional view of the burner with certain parts being cut out, FIG. 4 being a sectional view taken along the line IV--IV of FIG. 3, FIG. 5 being a sectional view taken along the line V--V of FIG. 3 and FIG. 6 being a perspective view of the frusto-conical blast supply member; and

FIG. 7 to FIG. 9 illustrate still another embodiment in which a stream of air supplied under pressure and mixed with a gasified fuel and steam is heated into a hot blast before being mixed therewith, FIG. 7 being a vertical sectional front view of the burner with certain parts being cut out, FIG. 8 being a side view thereof and FIG. 9 being a sectional view taken along the line IX--IX of FIG. 7.

The construction of the gasified fuel burner in basic form according to the invention shown in FIG. 1 and FIG. 2 will now be described. 1 designates a combustion cylinder defining therein a gas chamber 2 having a combustion plate 3 mounted at its periphery for ejecting a mixture of gasified fuel and steam therethrough for combustion. An opening 4 is formed substantially in the central portion of the gas chamber. A diffuser-vaporizer 5 formed with an opening 6 disposed in spaced juxtaposed relationship to the opening 4 is mounted in combustion cylinder 1 and supported for rotation by a shaft 7 extending through the gas chamber 2 and its opening 4. A fuel scattering clearance 8 is formed between the opening in the diffusion-vaporizer 5 and the opening 4 in the gas chamber 2.

The diffuser-vaporizer 5 may be provided on its inner surface with a rough material layer by mounting thereon a wire netting 9 for promoting diffusion and vaporization of the liquid fuel. Alternatively, the wire netting 9 may be done without and a smooth material layer may be provided instead.

10 designates a frusto-conical blast supply member coaxial with the rotary shaft 7 and extending through the gas chamber 2 into the diffuser-vaporizer 5 to supply a stream of air under pressure to the diffuser-vaporizer 5 and then to the gas chamber 2. 11 is a fuel supply line for supplying a liquid fuel to the inner surface of the diffuser-vaporizer 5 while 12 is water supply line for supplying water to the inner surface of the diffuser-vaporizer 5. The fuel supply line 11 and the water supply line 12 open in the vicinity of diffuser elements 13 and 14 respectively which are separately connected to the rotary shaft 7 for supplying a liquid fuel and water to the inner surface of the diffuser-vaporizer 5. Alternatively, the fuel supply line 11 and the water supply line 12 may be made to open in the vicinity of one diffuser element 13, in place of two diffuser elements 13 and 14 respectively, for supplying a liquid fuel and water to the inner surface of the diffuser-vaporizer 5. 15 is an ignition plug.

In operation, the rotary shaft 7 is rotated to operate the diffuser-vaporizer 5 and at the same time a stream of air is supplied under pressure through the frusto-conical blast supply member 10 to the inner surface of the duffuser-vaporizer 5. Then, a liquid fuel is supplied to the surface of the diffuser element 13 which is rotating with the rotary shaft 7. The supply of liquid fuel delivered to the diffuser elements 13 moves to the inner surface of the diffuser-vaporizer 5 while spreading in all directions. The liquid fuel moves and spreads quickly and uniformly by virtue of centrifugal forces exerted on the rotating diffuser-vaporizer 5 and the action of the stream of air supplied under pressure to the diffuser-vaporizer 5 through the frusto-conical blast supply member 10. Thus, the liquid fuel mixes with a portion of the air stream and scatters in atomized particles through the fuel scattering clearance 8, into the combustion cylinder 1 where combustion of the liquid fuel in liquid state is initiated when it is ignited.

As combustion of the liquid fuel is started as a preliminary combustion step, the rotating diffuser-vaporizer 5 is heated at once, so that the liquid fuel supplied to its inner surface through the fuel supply line 11 is vaporized into a gasified fuel while quickly moving and scattering along the diffuser-vaporizer 5 which gasified fuel is supplied, together with the stream of air supplied under pressure through the frusto-conical blast supply member 10, to the gas chamber 2 where they are mixed together and the mixture is ejected through the combustion plate 3 for combustion.

When combustion of gasified liquid is initiated as aforementioned, water is supplied through the water supply line 12 and the rotating diffuser element 14 and sprinkled on to the surface of the diffuser-vaporizer 5. The water is vaporized and expands to generate steam while it moves and spreads quickly on the diffuser-vaporizer 5 by virtue of heating of diffuser-vaporizer 5, centrifugal forces exerted on the rotating diffuser-vaporizer 5 and the action of the stream of air supplied under pressure through the frusto-conical blast supply member 10. Thus, the diffuser-vaporizer 5 simultaneously performs the functions of producing a gasified fuel and generating steam, and the gasified fuel and steam produced in this way are mixed together. The mixture is thoroughly mixed with the stream of air while the former is introduced under pressure into the gas chamber 2 by the latter, and the mixture of gasified fuel, steam and air is ejected through the combustion plate 3 for combustion. Flames produced when such mixture of gasified fuel, steam and air is burned have a high temperature because the mixture contains moisture.

FIG. 3 to FIG. 6 illustrate a second embodiment of the invention which represents a modification of the aforementioned basic form of the burner according to the invention. As shown, the burner further comprises a steam generating annular chamber 16 disposed at the periphery of a flame ejection opening 17, and a steam line 18 connected at one end to the steam generating annular chamber 16 and opening at the other end in the frusto-conical blast supply member 10. By this means, the liquid fuel is converted into a gasified fuel by the rotating diffuser-vaporizer 5 while the water is quickly heated and generates superheated steam in the steam generating annular chamber 16 as it is heated by the heat produced by precombustion of the liquid fuel in liquid state, with the superheated steam being ejected into the blast supply member 10 through which the stream of air moves under pressure. Thus, the arrangement is effective to obtain a better mixing of the gasified fuel with the superheated steam so that combustion of the gasified fuel can be carried out more satisfactorily than in conventional gasified fuel burners.

The steam generating annular chamber 16 is coated on its inner surface with a moisture-containing material layer 19 for converting water into steam as quickly as possible by precombustion and heating of the liquid fuel in liquid state on the diffuser-vaporizer 5. Water is supplied through a water supply line 20 opening at one end in the steam generating annular chamber 16. In the second embodiment shown and described above, a suitable number of rotary guide vanes 21 best seen in FIG. 6 may be provided at the forward end of the frusto-conical blast supply member 10 to cause the stream of air supplied under pressure through the blast supply member 10 to be ejected in a direction opposite to the direction of rotation of the diffuser-vaporizer 5 so as to thereby promote diffusion, scattering and vaporization of the liquid fuel.

Characteristic of the second embodiment described above is that the liquid fuel and water are vaporized separately in the diffuser-vaporizer 5 and steam generating annular chamber 16 respectively. This arrangement permits vaporization and combustion of not only a small volume of fuel and water but also a large volume thereof to be carried out any time as desired. Besides, the steam generated in this way is a superheated steam which is capable of attaining better mixing with gasified fuel to enable vaporization and combustion of liquid fuel to be carried out with a higher degree of efficiency.

FIG. 7 to FIG. 8 illustrate a third embodiment which represents a modification of the second embodiment. As shown, the third embodiment of the invention further comprises means for converting the stream of air supplied under pressure through the frusto-conical blast supply member into a hot blast before producing a mixture thereof with the mixture of gasified fuel and superheates steam. More specifically, such means comprises a hot blast producing annular chamber 22 disposed directly outside the steam generating annular chamber 16 described with reference to the second embodiment, a blast duct 23 connected at one end to the hot blast producing annular chamber 22 to supply a cool blast to the interior of the hot blast producing annular chamber 22, and a hot blast duct 24 connected at one end to the hot blast producing annular chamber 22 and opening at the other end in the interior of the blast supply member 10. The steam line 18 connected at one end to the steam generating annular chamber 16 opens at the other end in the interior of the hot blast duct so as to thoroughly mix superheated steam with hot blast and injecting the mixture into the diffuser-vaporizer 5 together with the stream of air supplied under pressure through the frusto-conical air blast member 10 thereby attaining better mixing of the gasified fuel with the superheated steam and increasing the volume of gases. Thus, combustion of the gasified liquid fuel can be carried out satisfactorily.

From the foregoing description, it will be appreciated that according to the invention, the rotating diffuser-vaporizer 5 is quickly heated by precombustion of the liquid fuel in liquid state, and not only the liquid fuel supplied to the diffuser-vaporizer 5 thereafter but also the water supplied thereto is vaporized simultaneously. The gasified fuel and steam produced in this way are mixed together with a stream of air supplied under pressure through the blast supply member to produce a perfect mixture of gasified fuel, steam and air for combustion. The invention offers the advantages of permitting to greatly economize on fuel, increasing the volume of gases to sustain combustion at elevated temperatures over a prolonged period, and producing flames which contains mixture because of mixing of fuel with steam to thereby naturalize noxious components of gases. Thus, the gasified fuel burner according to the invention is devoid of the danger of emitting noxious gases and highly efficient in operation.

While the invention has been shown and described with reference to some embodiments thereof, it is to be understood that the invention is not limited to the specific forms of the embodiments and that many changes and modifications may be made therein without departing from the spirit and scope of the invention.