US3751211A

US3751211A - Method for burning liquids

Info

Publication number: US3751211A
Application number: US00164498A
Authority: US
Inventors: A Rasconi
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-07-21
Filing date: 1971-07-21
Publication date: 1973-08-07
Anticipated expiration: 1990-08-07

Abstract

Liquid fuels such as hydrocarbon fuels are burned in an upright cylindrical chamber by introducing the liquid in a continuous stream into a peripheral zone at the bottom of the chamber, and simultaneously introducing air in a direction downwardly inclined and inclined away from the center of the chamber so as to create a vortex motion of the air in the chamber thereby to atomize the fuel.

Description

United States Patent [191 Rasconi Aug. 7, 1973 [54] METHOD FOR BURNING LIQUIDS 2,175,866 10/1939 Arnold 431/173 Inventor: A e a d e Rasconi, Chem d la 3,200,870 8/1965 Hanley et a1 431/173 Fauvette 4b, 1012 Lausanne, Switzerland Primary ExaminerEdward G. Favors [22] Filed: July 21 1971 Att0rneyYoung & Thompson [21] Appl. No: 164,498

Related [1.8. Application Data [57] ABSTRACT [62] Division of 4 1969 Liquid fuels such as hydrocarbon fuels are burned in an abandoned upright cylindrical chamber by introducing the liquid in a continuous stream into a peripheral zone at the bot- [52] US. Cl. 43 1/9, 43l1/l73 tom of the chamber, and Simultaneously introducing air CL... in a direction downwardly inclined and inclined y [58] Field of Search 431/173, 9 from the center of the chamber so as to create a vortex motion of the air in the chamber thereby to atomize the [56] References Cited I fuel UNITED STATES PATENTS 2,501,688 3/1950 Peeling 431/335 X 1 Claim, 2 Drawing Figures METHOD FOR BURNING LIQUIDS This application is a division of copending application Ser. No. 875,631, filed Nov. 12, 1969 and now abandoned.

BACKGROUND OF THE INVENTION With known methods of burning liquid fuels in conventional burners to which the liquid fuel and the combustion air are fed, it is not possible to burn fuels of widely different nature and'quality (viscosity, calorific value), or fuels such as used oils containing, for instance, iron filings.

OBJECT OF THE INVENTION The purpose of the invention is to provide a method enabling any kind of fuel to be used, and even allowing the simultaneous use of several different fuels. The

method according to the invention comprises using a PREFERRED EMBODIMENT OF THE INVENTION The accompanying drawing illustrates, by way of an example, an embodiment of the invention.

FIG. 1 is an axial section of this embodiment, and

FIG. 2 is a section along the line 2-2 in FIG. 1.

The illustrated method involved in the use of a stove which comprises a vertical cylindricaibarrel 1 having a casing 2, made of metal or masonry for instance, and an inner lining 3 of fire-brick. The upper part of the stove may be provided with a cap having an opening for the discharge of the combustion gases or with an explosion flap in case the stove is to be connected to a boiler or to another device for the recovery of the calorific energy. These components are not shown. 1

The'base of the stove comprises four nozzles 4 situated in the lower part of the stove and opening in the bottom of the latter which constitutes a combustion chamber 5. Each nozzle forms an angle with the corresponding diameter of the stove, as shown in FIG. 2, and constitutes an air inlet oriented in such a manner as to produce a vortex motion of the air in the combustion chamber. The air thus introduced, owing to its vortex motion and to its flow towards the upper part of the stove, takes on a helicoidal motion of reduced pitch. The air may be injected at a very high speed through the nozzles, for instance at a speed of from 80 to 100 m/s, so that the vortex motion may be very fast and sweep the whole surface of the combustion chamber. The angle of injection is chosen according to the dimensions and the operating characteristics of the stove. The latter may comprise means to adjust the direction of the incoming combustion air, i.e. the angle formed by each nozzle 4 with the corresponding diameter of the stove.

In the illustrated embodiment, the nozzles constitute a single bank, but several banks of nozzles could be arranged over the height of the combustion chamber or in the bottom of the stove.

The air is led to the nozzles 4 by a manifold 6. In the case where there are several banks of nozzles, a single manifold may feed all the nozzles, or else each bank may have its own manifold. These may then be separately fed or else-they may all be connected to a common manifold.

The stove comprises, placed above the nozzles 4 and the manifold 6, four nozzles 7 fed by a manifold 8, the air thus introduced into the stove being destined to adjust the temperature of the upper part of the stove.

The combustion air introduced through the nozzles 4 and the air for adjusting the temperature introduced through the nozzles 7 can be furnished by one or more blowers, having means for adjusting the air delivery in the distributing manifold.

The stove comprises in its bottom ducts 9 constituting fuel inlets, the ducts 9 opening into the combustion chamber 5 through ports 10 arranged in the peripheric zone of the floor 11 of this chamber. The position of the ports 10 in relation to the nozzles 4 is such that the air jet formed by these nozzles instantaneously atomizes the fuel to fine particles which ignite immediately and the combustion of which is practically instantaneous. Owing to the helicoidal motion of the combustion air, combustion can take place in a combustion chamber 5 of reduced height, which may be of the order of the diameter. of the stove, for instance. The

combustion of the fuel introduced through the ducts 9 is started by means of a small auxiliary burner placed in one of the nozzles 4 (this burner is not shown). This burner may be provided with a cell for checking the flame.

To start the stove, when this stove is used for the combustion of a fuel (used oil, for instance) without using a boiler to recover calorific energy, the auxiliary burner is first started, this auxiliary burner burning oil fuel. After a time interval of the order of 15 to 30 seconds, combustion air is injected through the nozzles 4 after checking the operation of the auxiliary burner. As soon as the air flows, fuel is injected through the ducts 9. After a short lapse of time, of the order of 15 seconds, the auxiliary burner is cut off and the stove goes on burning by itself. The normal rate of operation of the stove may be adjusted by governing the air/fuel ratio in such a manner as to give an excess of air enabling peak conditions to be absorbed in case of a fuel having a nonuniform calorific value.

Several fuel inlets are provided, so as to inject simultaneously into the combustion chamber several fuels having very different characteristics, for instance fuels which do not mix well or not at all and having very different calorific values. The separate injection of the fuels enables a mixture, after atomization, to be obtained in the chamber having a practically constant calorific value.

The operation of the stove depends on several factors: the variable calorific value of the fuel, minimum and maximum service temperature, etc. It is thus'necessary to be able to vary the different factors which have to be taken into account, such as the rate of delivery of the fuel, the rates of delivery of the combustion air and' the thermal regulation air, and this by manual or by au tomatically controlled means.

The minimum operating temperature is a function of the kind of fuel used and must be sufficient to ensure complete combustion of the latter and to avoid smells.

This temperature is generally above 800 C. The maximum temperature is a function of the quality of the fire bricksforrning the lining 3 and must not exceed the temperature which this lining is able to stand.

which is inclined away from the center of the chamber thereby to create a vortex motion of the air in the bottom of the chamber with the air entering the chamber at a speed sufficient to atomize the fuel in the chamber,

said speed being about to meters per second.

Claims

1. A method for burning liquid fuel in an upright cylindrical combustion chamber, comprising introducing a continuous stream of liquid fuel into a peripheral zone of the bottom of the chamber, and simultaneously introducing air separately from said fuel into the lower part of the chamber in the form of at least one stream which is inclined away from the center of the chamber thereby to create a vortex Motion of the air in the bottom of the chamber with the air entering the chamber at a speed sufficient to atomize the fuel in the chamber, said speed being about 80 to 100 meters per second.