US3647347A

US3647347A - Flash vapor burner

Info

Publication number: US3647347A
Application number: US53059A
Authority: US
Inventors: Hosein M Shakiba
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-07-08
Filing date: 1970-07-08
Publication date: 1972-03-07
Anticipated expiration: 1989-03-07

Abstract

The flash burner utilizes the total thermal efficiency of the fuel to develop heat. The fuel is kept under high pressure and heated beyond the boiling point. This superheated liquid fuel which is under pressure, enters into the low-pressure area of the combustion channels, where it flashes into vapor and prompt mixing of this vapor with air causes complete burning and heat production. The device has the advantages of great fuel economy, no likelihood of causing air pollution, and low maintenance.

Description

O United States Patent [151 3,647,347

Shakiba 1451 Mar. 7, 1972 54] FLASH VAPOR BURNER 1,473,657 11 1923 Wiederwax ..431/243 x 2,087,399 7/1937 Elfving et al.. ..431/36 [72] Inventor: Hosem M. Shakrba, 4527 Walnut Street, 2 200 826 5 1940 J h 431 6 Philadelphia, Pa 19139 1 o nson /3 22 Filed; July 1970 Primary Examiner-Carroll B. Dority, Jr.

AttorneyJackson, Jackson and Chovanes [21] Appl. No.: 53,059

[57] ABSTRACT [52] US. Cl ..43l/37, 431/41, 431/242, The flash burner utilizes the total thermal efficiency of the fuel 431/243, 431/353 to develop heat. The fuel is kept under high pressure and [51] Int. Cl ..F23n l/00 heated beyond the boiling point. This superheated liquid fuel [58] Field of Search ..431/3638, 243, which is under pressure, enters into the low-pressure area f 431/41 the combustion channels, where it flashes into vapor and prompt mixing of this vapor with air causes complete burning [56] References Cited and heat production. The device has the advantages of great fuel economy, no likelihood of causing air pollution, and low UNITED STATES PATENTS n ii- 1,448,802 3/1923 Hoffman ..431/243 15 Claims, 6 Drawing Figures HEATER THERMOSTAT SOLONOlD VALUE PAIENIEBMAR 7 I972 3 647, 347

SHEET 1 BF 2 SOLONOlD VALUE #EQLZTQ FIG?) INVENTOR. 5 HOSEIN M. SHAKIBA ATTORNEYS.

PATENTEDMAR 71972 3,547; 347

SHEET 2 OF 2 PRESSURE GAUGE CONTROLS FUEL. VALVE INVENTOR. HOSE N M. S AK BA ATTO R N E YS.

tion.

FLASH VAPOR BURNER DISCLOSURE OF lNVENTlON The invention relates to flash vapor burners, inducing combustion and burning of fuel inside the burner and releasing produced heat into the place to be heated.

In accordance with the invention, fuel is heated to a temperature which would make it boil at atmospheric pressure but is prevented from boiling because it is held under high pressure. This fuel is released through an orifice, connected to a cone cup controlled by a solenoid valve, into a combustion area in which it mixes with air to produce combustion. The cone cup is angled in a manner to sweep the entire inner area of combustion channels. The preheating of the fuel is accomplished by a heater in the fuel compartment at the start, but then is preheated by heat transfer from the combustion channels. The air is propelled by a blower and also preheated by heat transfer from the outer surface of combustion channels.

Thus, the fuel is compressed in the fuel pressure tank connected to the fuel compartment by a pump, and it is released to the low-pressure combustion channel area where it undergoes atomization in a very complete form.

There is no chance in the fuel compartment to separate impurities and thus clog inner areas because the high pressure prevents vaporization prior to entry to the combustion channel area.

The operation is very flexible in reference to the consuming fuel, is primarily intended for industrial type fuel such as No. 2 to No. 6 petroleum.

Very complete combustion takes place, and there is no creation of pollution of the air.

The burner can be made at low cost and is low in maintenance.

The outer barrel is relatively cool because the passing air carries the heat built up.

ln the drawings I have shown diagrammatic figures which are useful as examples of the invention, and at the same time which are convenient in illustration and satisfactory in operation.

FIG. I is a longitudinal section of the burner of the inven- FlG. 2 is a section of FIG. 1 on the line 22.

FIG. 3 is a broken side elevation of the burner of the invention.

FIG. 4 is a diagrammatic section on the line 4-4 of FIG. 1, with the housing broken away to show the blower.

FlG. S is a side elevation of the combustion chamber and mounting plate.

FIG. 6 is a front view of the mounting plate and outer shell omitting the internal details.

US. Pat. No. l,4l9,380 provides means to greatly increase the temperature of the fuel before it is introduced into the combustion chamber. A superheater is provided in the form of a closed coil preheated by the combustion chamber. The liquid fuel passes through this coil and is raised to high temperature before it is brought into the combustion chamber. This breaks down heavy materials before the oil flows through the porous walls of the combustion chamber.

US. Pat. No. 3,195,606 deals with the use of a pilot flame to promptly ignite the fuel coming through the fuel nozzle, the pilot flame being coextensive with part of the main flame.

US. Pat. No. 433,806 relates to the introduction of oil sprayer vapor into a combustion chamber and the mixing of it with air.

US. Pat. No. 641,776 shows the conversion of high-pressure fuel to low pressure as it issues from a burner.

Considering FIG. 1, primarily, the main body of the burner is formed by combustion channels 18 which are enclosed in housing 7 and having a depth as indicated at 19. The combustion occurs in the area encircled by combustion channels. The fuel compartment is embedded in the top part of the channels and it is in heat transfer relationship with them, and the heat of combustion. The fuel is pumped into pressure tank 2 from where it goes to fuel compartment 5 through pipe 6. The air contained within these parts will be replaced by fuel and the displaced air accumulates on the upper part of pressure tank 2.

Within the fuel compartment there is a tubular electric heater 8 to preheat the fuel to start the operation, the heater being suitably placed in the lower part of the fuel compartment. Also in the fuel compartment there is a thermostat 9 which activates a solenoid valve 3, to allow the fuel to enter the combustion area through nozzle 12 when it is at suitable temperature. (It will be understood that if preferred the control 9 may be a pressure valve which is in effect thermostatic rather than a valve directly controlled by temperature.) An opening 4 connects the fuel compartment 5 with the solenoid valve 3.

The fuel enters the fuel compartment 5 and heats up by the heat element until it reaches a predetennined temperature at which time the signal from the thermostat opens the solenoid valve and fuel is allowed to enter the combustion area through nozzle 12. While the fuel is being heated up in compartment 5,, the pilot torch 28 heats up the area of combustion. When the combustion of fuel starts, there will be further heat built up in compartment 5, until it reaches the upper range of the thermostat 9, which now turns off the heat elements 8 and pilot torch 28. From this stage on the burner is in steady state operation.

Pilot torch 28 has a gasline 13 which ignites the fuel and has an electric line to a spark tip 14 which ignites the gas. The pilot torch thus formed heats up the area of the barrel and helps to start the burner and also ignites the fuel. Also pilot torch 28 forms an obstruction in the path of high-speed wind which causes the air blown to be diverted from the nozzle area, since the pilot torch stands between the airstream and the nozzle.

The combustion channels 18 are longitudinal and serve to increase the area of the combustion chamber. The combustion chamber walls of ceramic or of metal (cast iron) serve as a heat adjusting medium since it conducts the heat absorbed from combustion to the beginning of the barrel, where it further heats up the air and vapor, also it causes a turbulent mixture of air and of fuel and permits the burning of all suspended particles.

There is a conventional air filter 30 to filter the oil prior to its entry in compartment 5.

An outer cover 20 surrounds the burner and provides an opening 17 around the mounting plate 21 from which inlet air is drawn. The combustion chamber has a front extension 25. Blower 24 within a housing 29 draws in the air within the cover 20 around the burner, thus preheating the air. The air heats up by passing through the area 23 and is further heated by the heat transfer from the beginning of the combustion channels as it is blown by the blower.

The blower 24 is turned by motor 31 which has a shaft 15 through which it operates pump 10 through ofi' center cam bearing 16 by rocker arm 11. This pump 10 pumps the fuel into the pressure tank and pressurizes the content of the tank including its residual air to maintain continuous operation. The quantity of fuel pumped in should be slightly more than the quantity of fuel released through the nozzle 12. The air in pressure tank 2 collects on top of the fuel and acts as a shock absorbing medium. The air also operates the pressure gauge 1 in the tank, which by a well-known switch turns off the electricity when the pressure drops excessively low, thus preventing operation of the solenoid valve 3 and shutting down the burner.

There is a pressure release valve 27 which allows the fuel to bypass through pipe 26 and return to the low-pressure fuel reservoir in case of excess pressure due to operation of the pump or excessive heat. The air passes in contact with outer surface of the combustion channels through punched out

sections

36 and 37 around housing in the combustion chamber wall 18 which allows the air to pass over the outer surface of the combustion channels to heat it more effectively. The hous- OPERATION When the heater is turned on, electric heater 8 starts to heat the fuel in fuel compartment which is under pressure, the gas torch ignited by the electric spark begins to heat up the inner area of the combustion chamber. When the temperature of the fuel heats up above the normal temperature boiling point, but of course the fuel is unable to vaporize because it is under pressure, thermostat 9 opens the nozzle 12 and the fan starts to blow air inside the combustion chamber and the fuel will be pumped in pressure tank 2.

When the fuel in fuel compartment 5 gets hot, the thermostat 9 switches off the electric heater 8, and the pilot torch.

The pilot torch ignites the fuel and the combustion heats up the fuel together with the electric heater 8, and after some time the temperature inside the fuel compartment is high enough and shuts off the electric heater and the pilot torch.

Fuel vaporizes since it is released from the pressurized compartment 5 into the low-pressure combustion area and is further heated up by heat energy stored in the combustion channels. lt completely burns including impurities which would otherwise cause soot and pollution.

When the burner is turned off by any suitable external means, such as manual control of the fuel valve or control by the house thermostat, the nozzle 12 shuts off and therefore there will be no more flame, but the fan and the pump continue working for a few minutes to carry excess heat from the combustion chamber and to pressurize the pressure tank 2 in order that the system is ready for the next operation.

In view of myv invention and disclosure, variations and modifications to meet individual whim or particular need will doubtless become evident to others skilled in the art, to obtain all or part of the benefits of my invention without copying the structure shown, and I therefore claim all such insofar as they fall within the reasonable spirit and scope of my claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a flash vapor burner, a combustion chamber having channels in which the vapor is burned, a fuel compartment in heat-transfer relationship with the combustion chamber, a pump supplying fuel to the fuel compartment and maintaining it at a pressure sufficient to allow it to remain liquid when it is above the boiling point under ambient pressure in the combustion chamber, a nozzle discharging the fuel into the combustion chamber, a thermostatic valve controlling the discharge to the nozzle from the fuel compartment, and blower means for supplying air to the burner in heat transfer relationship to the combustion chamber to preheat the air.

2. A burner of claim 1, in combination with a pressure tank between the pump and the fuel compartment, containing air, and maintaining pressure on the fuel in thefuel compartment.

3. A burner of claim 2, in combination with a bypass around the pump and a pressure controlled relief valve in the bypass.

4. A burner of claim 3, in combination with pressure cutoff means in the pressure tank for preventing fuel from passing through the nozzle when the pressure drops below an operative level.

5. A burner of claim 4, in combination with a gas jet in the combustion area and a spark gap for igniting the gas jet.

6. A burner of claim 5, in combination with an electric heater in the fuel compartment, and means for cutting off the electric heater when the fuel is sufficiently heated.

7. A burner of claim 6, in which the combustion channels in the combustion area increase the internal surface thereof and are directed longitudinally in the direction of fuel flow.

8. A burner of claim 1, in combination with a bypass around the pump and a pressure controlled relief valve in the bypass.

9. A burner 0 claim 1, in combination with a pressure tank between the pump and the fuel compartment, containing air, maintaining pressure in the fuel compartment and pressure cutoff means in the pressure tank for preventing fuel from passing through the nozzle when the pressure drops below an operative level.

10. A burner of claim 1, in combination with a gas jet in the combustion chamber and a spark gap for igniting the gas jet.

11. A burner of claim 1, in combination with an electric heater in the fuel compartment, and means for cutting off the electric heat when the fuel is sufficiently heated.

12. A burner of claim 1, in which the combustion channels in the combustion chamber increase the internal surface thereof and are directed longitudinally in the direction of fuel flow.

13. A burner of claim 1, having means to induce combustion inside the burner barrel and release the heat produced into the area which is to be heated.

14. A burner of claim 1, being provided with a housing around the combustion channels, and having means for preheating the air in two stages, the one stage being provided by the housing and adjoining portion of the combustion channels, and the other stage provided by the beginning of the combustion channels.

15. A burner of claim 1, having means for converting the fuel instantly from pressurized liquid into vapor.

Claims

2. A burner of claim 1, in combination with a preSsure tank between the pump and the fuel compartment, containing air, and maintaining pressure on the fuel in the fuel compartment.

9. A burner of claim 1, in combination with a pressure tank between the pump and the fuel compartment, containing air, maintaining pressure in the fuel compartment and pressure cutoff means in the pressure tank for preventing fuel from passing through the nozzle when the pressure drops below an operative level.