US1823381A - Fuel burner - Google Patents

Description

C'. J. sHERwooD 'sept 15, 1931.

FUEL BURNER Filed Sept. 28, 1927 2 Sheets-Sheet l INVENTOR.

@@LMm r @42m ATTORNEYS.

Sept 15, 1931- J. sHERwooD 1,823,381

FUEL BURNER Filed Sept. 28, 1927 v 2 Sheets-Sheet 2 IN V EN TOR.

A TTORNEYS.

Wj www MILA/ff@ r MM Patented Sept. 15, 1931 CABLYLE J. SHERWOOD, OF LOS ANGELES, CALIFORNIA FUEL BURNER Application filed September 28, 1927. Serial No. 222,492.

This invention relates to burners particularly 'adapted to furnaces, commonly known as industrial furnaces and furnaces for power purposes, such as illustrated in my .5 co-pending application entitled Combination burner mounting and air control, filed December 14, 1926, Serial Number 154,692, and especially to a multiple fuel type of burner which is capable of beingn alternatelo 1y used with any one or several fuels, such as powdered coal, powdered coke, liquid fuels, gas, etc.

The modern and most advanced method of operating furnaces of the industrial type is by the so-called mechanical method, i. e.,

either atomized oil or powdered coal is ro- ]ected into the furnace through a reglster or opening in the brick work, along with the necessary air to support combustion.

so Burners of this character are' usually limited to one type of fuel. This is a decided disadvantage as Athe problem of power plant operation is principally an economical one. Advantage cannot be taken of the lowest priced fuel and there is always a possibility of a shut down vfrom shortage of fuel due .to strikes, trans ortation failures, etc.

The object o the present 'invention is to generally improve and simplify the 'construction and operation of burners of the character described, and es )ccially to provide a burner which iscap: le of being al ternately used with any one or a combination of several fuels, s uchas powdered coal, with oil, or gas, etc.

The burner is shown by way of illustration in the accompanying drawings, in

which: y

Fig. 1 is a central vertical longitudinal section through the burner and a portion of the burner frame,

Fig. 2is a front View of the burner,

Fig: 3 is'a front view partly broken away and partially in section, the section being taken on line III-III, Fig. l, 1 Fig. 4 is an enlarged cross-section on line IV-IV, Fig. 1, y

Figs. 5 and 6 are enlarged sectional views of theA owdered fuel mixers.

Fig. is a view in side elevation showing the oil burner arrangement adapted t0 be used with the structure of Fig. 1.

Referring to the drawings in detail and particularly Fig. 1, A indicates the brick work forming the front wall of a furnace, and B the wall plate of the furnace. Formed in the brick work is a circular opening C commonly known as the firing orifice, and positioned against the furnace front plate B in any suitable manner is a gas burner D and a registery E, which in this instance supports two burners, to-wit, an oil burner as indicated in Fig. 7 at F and a powdered fuel burner generally indicated at Gr.v The gas burner illustrated is described in detail in my co-pending applica-4 tion referred to. It is interposed between the brick work A andthe register E, and gas is delivered thereto through a supply pipe 2. The register proper consists of an exterior ycylindrical shell or drum 3 which is bolted or otherwise secured to the furnace plate B, as indicated at 4. Mounted interior of the drum 3 and interspaced and concentric therewith is an inner drum 5, this being secured to the outer drum by bolts 0r the like as shown at 6. Formed on the outer drum 3 is a pair of hinge lugs 7 and formed on the opposite side thereof is a securing bracket 8. Hingedly secured betweenthe lugs 7 is a U-shaped bracket 9, and forming a part of the bracket is a cylindrical-shaped bearing' tube 10. Supported by the tube 10 isa damper door 11, on the inner face of which is formed a liner 12 and carried by the damper is a plurality of angularly disposed vanes 13 (see Figs.

1 and 3) through which air to support combustion is admitted. The tube l0 has a cam groove 14 formed on its exterior surface. The damper door isV provided with a lhub 15 and a set screw 16 extends through the hub and into the cam groove. The damper door is; furthermore, provided with a handle 17 and by vrotatmg the door throu h means of the handle, the door is move longitudinally on the tube 10 to or away from the drums/3 and 5, and as such regulates the amount of air admitted, the ,damper door being secured in its adjusted position by 'means of a set screw or the like will hereinafter be described. Secured to the outer end of the tube 10 by flanges and bolts as indicated at 22 is an elbow-shaped casting 23. This is, in actual practice, connected with a Crusher or like device whereby air and powdered fuel, such as coal orcoke is delivered. Mounted within the tube 10 and the elbow member 23 is one or more rings, as indicated at 24 (see Figs. 1, 4, 5 and 6), and formed within each ring is a plurality of spiral or angularly arranged vanes or blades 25. The blades in one ring are preferably turned in a right-hand direction and theblades in the opposite ring in l a left-hand direction, this being more or less essential to produce thorough agitation or mixing of the powdered fuel and the air passing through the elbow member 23, the tube 10 and the sleeve 19. Formed on the lower end of the elbow member 23 is a hub like extension 30 which is internally cored or drilled to form a central opening 31 which aligns with the longitudinal axis of the sleeve 19 and the tube 10. It will thus be seen that the extension 30 serves as a support for the pipe or nozzle of the oil burner generally indicated at. F in Fig. 7. The.

opening 31 is, however, normally closed by means of a'plug or core, such as shown at 33, when powdered fuel is being used. On the other hand the plug is removed and the burner F inserted when fuel oil is to be utilized. In actual practice it Ahas been found that longitudinal adjustment of the sleeve and the shield 20 with relation to the by'pushing on the handles, the sleeve and" shield are moved towards the burner oritice, the exact positionfinally assumed being determined by the fuel which is being burned and the amount of air mixture and atomzation that is desired. In actual practice, if a powdered fuel is tobe utilized, such as powdered coal or the like, it' is only necessary to connect theelbow member 23 with a standard form Vof mechanism which is capable of delivering the fuel in a powdered form, together with air. Any tendency of the powdered fuel and the air delivered through the elbow to stratify -while passing through the elbow is broken before such possible stratification passes through the burner shield 20 by the insertion of agitating vanes indicated at 25'as the vanes cause the air and fuel to swirl, first in'one direction and then in an oppositev direction. The mixture of powdered fuel and air is thus thoroughly agitated and swirling when entering the sleeve 19 and as such discharges from the frusto-conical shield 20. Air will at the same time be admitted through the vanes 13, which are angularly disposed, and as previously stated, the air entering at this point will swirl in a direction opposite to that of the fuel mixture leaving the shield 20. A thorough co-mingling of air and fuel is thus obtained atthe burner orifice C and efficient combustion is, accordingly, obtained, the thorough co-mingling of air and fuel being so promoted by a portion of the air entering through theslots 21 of the shield 20. It is, of course, possible to burn gas at the same time by merely opening the valve indicated at 2a or it is possible to burn either fuel alone, the gas burner being preferably ignited to begin with so as to heat the furnace and to ignite the powdered fuel when it is first turned on. Again, if it is desired to change from powdered fuel to liquid fuel,

such as oil or the like, it is only necessary to remove the plug 33 and to insert the pipe ployed so that a highly atomized cone-- shaped spray will be discharged from the end of the nozzle. In that :instance the sleeve 19 and shield 20 may be retracted so as to be out of the way of the nozzle. The mixing vanes 25 will not interfere when the burner pipe or nozzle is inserted as the inner end s of the vanes or blades terminate and form a circular, central opening between themas indicated at 50 (see Figs. 1 and 4). The rods 40 do not interfere as they are disposed on opposite sides of the pipe 10 (see Fig. 4). It is, accordingly, onlynecessary to remove or replace the plug or core 33er remove the oil burner F in changing from one fuel to another.

The purpose of a multiple fuel burner using oil, gas and coal as a fuel is principally an economicione, as advantage can be taken of the lowest priced fuel in any locality. Upon shortage of one fuel, either of the remaining fuels available can be burned, thus reducing the possibility of a shut downfrom shortage of fuel.

The oil burner delivers oil to the furnace in the forni of a conically shaped atomized spray which completely fills the circular firing orifice so Jthat no air can reach the furnace Withoutnrst passing through the oil spray thus reducing to a minimum the quantity of unburned oxygen and expediting the combustion process. The proper amount of air for each size of fire is'regulated by means of thedamper door. Suitable adjustment is obtained by moving the burner sleeve 19 in a` horizontal.direction and locking vsame in the desired position. An air shield is provided at the apex ofthe spray cone to steady the fire or prevent the air from extinguishing same.

',l he coal burner is circumjacent to the oil burner, and utilizes the same air shield as the oil burner, for the same protective reasons. lihe air shield also forms the dischargenozzle for the coal burner and is, therefore, adjustable longitudinally so that the conical dust stream can be made to completely fill the firing orifice and prevent any free passage of air. '.lhe spray angle of the dust stream is regulated by means of spiral blades 25 inserted in the discharge nozzle which also tends to prevent stratifi cation of the fuel dust. To lincrease the spray angle of the dust stream, it is necessary to increase the'pitch angle of the spirals With relation to the longitudinal axis of the nozzle. To obtain' a Wide flame, the pitch angle of the spirals is approximately 90.

lVhile certain featuresl of the presentin vention are more or less specifically described, l wish it understood that various changes may be resorted to Within the scope of the appended claims.. Similarly, that the materials and finishes of the several parts employed may be such as the manufacturer may decide or varying conditions or uses may demand.

' Having thus described my invention, what claim and desire to secure byLetters Patent 1s l l. ln combination with a furnace Wall having an opening therein, a cylindrical drumadapted to be disposed in longitudinal central alignmentfvvith the opening in a furnace Wall, a damper structure disposed over one end of said drum and adapted to regulate the passage of air through the drum and the opening in said furnace Wall to the furnace, a bearing tube extending horizontally and being disposed iny fixed central longitudinal alignment With the drum, an elbow member in direct communication with the outer end of said bearing tube through "which member powdered fuel may be delivered to the bearing tube, a tubular sleeve mounted to telescope Within the bearing tube and projecting towards the -furnace Wall opening, means for adjusting said sleeve longitudinally of the bearing tube Within which -it is mounted and a frusto Vconical shield flaring at the opposite. end of the bearing tube, said shield being formed with radial openings occurring at equal spaced intervals in the shield and extending for a length in the sleeve whereby air passing around the sleeve and through the drum may pass through the shield and commingle With the powdered fuel being delivered from the bearing tube.

2.1n combination With a furnace Wall having an opening therein, a cylindrical drum open at its opposite ends, one end communicating with the opening in the furnace Wall, said drum being of relatively large diameter, a cross member extending across one end of the drum, a damper structure adapted to be carried by the cross member to regulate the flow of air through the drum, an annular gas burner at the opposite end of said drum, a cylindrical bearing tube carried by the cross member and extending in longitudinal central alignment With the drum, a tubular sleeve extending into the bearing tube and slidably mounted With relation thereto, the inner end of said sleeve being beveled inwardly, the opposite end of the sleeve flaring outwardly to form a frustoconical shield having a base diameter in excess of the diameter of the sleeve, said base being normally substantially in the plane of the gas burner diffusing openings formed in the side Wall of said shield and terminating in parallel portions formed around and along the sleeve, said openings being radially disposed with relation to the axis of the sleeve and the bearing tube, and means for operating said sleeve to cause it to slide Within the bearing tube.

3. In combination With a gas burner, a non-gaseous fuel burner, including a register comprising concentrically positioned drums open at their ends, said drums forming an annular recess, a register front having air directing vanes thereon, said vanes projecting into said annular recess, a bearing tube upon said register front, anongaseous fuel burner sleeve adjustably pos1- vtioned Within said bearing tube, means to prevent accumulations of fuel at the entrance to the last mentioned burner sleeve, and operating means to adjustably position said non-gaseous burner sleeve with respect to the firing conditions to be met Within a furnace being fired.

CARLYLE J. SHERW'OOD.

Images