US1852809A - Pulverized coal firing with subdivided flame - Google Patents

Description

April 5, 1932. w. KLEINOW I PULVERIZED COAL FIRING WITH- SUBDIVIDED FLAME Filed Oct. 22, 1929 W lli 1h \/"nto'r-: Walter- Klei now.

Patented Apr. 5, 1932' UNITED STATES parent oFFmE WALTER KLEINOW, F HENNIGSDORF, GERIvIANY,-ASSIGNOR T0 GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK rULvEn-izEn COAL FIRING Application filed October 22, 1929, Serial 170.

The present invention relates to pulverizedcoal firing with subdivided flame in which the device for introducing the pulverized coal consists of a nozzle tube or tubes with a multiplicity of adjacent outlets for ejecting into the furnace the mixture of coal dust and air in individual jets. Heretofore it has been the practice to inject the fuel at substantially right angles to the axial direction of the tube or tubes, and to introduce combustion air at substantially right angles to the direction of injection of fuel. If two parallel nozzle tubes are provided at the lateral walls of the furnace so that their outlet openings face each other, the burning dust jets will impinge against each other which will cause a large rising flame similar to that of ordinary grate firing. This flame will fill the entire fur nace space and, in the case of locomotives, it will fill the entire fire box.

Inasmuch as the fire boxes of the various types of locomotives for instance are varied in design, in one instance being short and wide and in another instance long and narrow, the paths followed by the flames are likewise very different. In the short-andwide design the above described way of in troducing the fuel has given satisfaction because the individual dust particles have a sufficiently large path within which they may be consumed and because a sufiicient time of combustion is attained thereby. The conditions are diiferent, however, in the case of locomotives with narrow fire boxes, since here, with a vertical impinging of the coal dust jets, the

time is not suflicient for complete ignition.

One object of my present invention is to provide an improved construction and arrangement whereby the path of the flames is lengthened and a better operation of the furnace is obtained. Another object of my invention is an improved arrangement of burners which permits a better operation of a furnace at low load.

For a consideration of what I believe to be novel and my invention, attention is directed to the following description and the claims appended thereto.

According to my invention, a multiplicity of nozzles is provided for ejecting the burn WITH SUBDIVIDED FLAME 401,551, and in Germany November 6, 1928.

ing material at an angle such that the flames are directed towards the air of combustion which enters'by way of the fire box wall. This arrangement insures the thorough mixing of the dust-air jets with the secondary air from the tube wall.

In the case of installations where the firing is continued for a considerable period at low load, it is not advisable to disperse the dust jets too much because, owing to the existing possibilities of heat radiation, too much heat may be withdrawn from the flre box, and this might cause extinction of the fire. Under hese conditions, the arrangement may be such that all jets converge toward one point as much as possible. This is obtained, in accordance with one embodiment of the invention, by arranging the walls which define the outlet nozzles in a manner such that they may be turned or adjusted so as to direct together and in the desired directions the individual. jets. This arrangement of nozzles can be applied to narrow as well as to wide fire boxes.

The direction which must be given to the fuel-air mixture upon leaving the slots of the burner tube can be obtained in different manners. For instance, the outlet slots may have such a shape that the fuel-air mixture is blown into the fire box in an inclined direction, or the guide vanes, which are provided in front of the outlet slots may be shaped in such amanner that they impart the desired direction to the dust-air mixture. Also, in special cases, the guide vanes may be made adjustable individually, in groups, or in their entirety, to regulate the trend of the path of the flames within the fire box so that the flames that come from diiferent directions will meet in the center of the fire box.

In the drawings, wherein there is illustrated an embodiment of my invention, Fig. l is a vertical longitudinal sectional view through a locomotive fire box; Figs. 2 and 3 are sectional plan views taken on line 22, Fig. 1, showing different arrangements of the discharge nozzles of the burners, and Fig. 4 is a perspective view partly broken away of one of the discharge nozzles.

Referring to the drawings, 1 indicates the fire box, and 2 indicates the ash box. Directto Eigzzt, they areshown aseach.Comprising.

a rectangular box 5, having, acover'plate .6 in which are arranged spaced vertical discharge slots 7. charge slots are walls or vanes 8 which define discharge nozzles for the fuel and air issuing fromthe slots 7... Above and below. thewalls or vanes 8 are conduits9 forthecirculatmn of cooling water, The secondary a r for,

combustion enters througha slot 10 formed in the front wall 111; of thefire box just beneath the-baflle plate 12. 13 indicates the tube, sheet of th e b oiler andla indicates the boiler. tubes. Accordingto. my invention, I so construct. and arrange theslots 7 and-the .walls or vanes 8 whichdefine thedischarge nozzles of the burner, that the. fuel-air .mixture issuing.

fron themis. discharged-at an angle other than a right angle to the face of the-burner and generally inclined toward the frontwall ll of the fire box.. By this arrangement, the

flame issuing from .the ,nozzles. is directedtoward the front wall andfiows against the .air

,mixture 1s blown into the Iurnace, said nozfor combustion entering-through{the slot 10. In this manner, all coal-dust particles are brought into contact with the air for combustion, andat the same time. the path of combustion within. the. fire box is lengthened. Because of this lengthening, and. particularl ,becauseof the intimate mixin of the ,beingprovided with a passage for :the adsecondary .air with thefiame, all coal dust.

particles will b-urn completely before they, reach .thetube sheet 13. It will be under stood in connection with a. fire box of this type, that the flames which issuefroanthe;

,. able guide. vanes arranged between said slots; 4. In combination, front,.lside and. rear oppositeburners, impinge against each other and rise gradually so that v the entire fire box! is filled. with the flames.

The direction of the .fuel-air mixtureissuing from the burners may bedefined by, the shape of the slots 7. .or by theshape of the;

walls or vanes .8 which ,definethedischarge nozzles, or by botlrmeans. If found desir able, the walls or vanes 8 which define the discharge nozzles-may be made adjustable, either individually orin groups. In the pres ent instance, the.,walls or vanes Sare shown as being suitably pivoted on the tubes 9, and,

ment shown is only. illustrative, and: that the.

Located between the dis- :alongtheside walls of said fire box comprising a pluralityof' guide vanes arranged in groups anddirected towards the'center i/ .of the vfire box;

In witness whereof I 'havehereto set my partly in a rearward direction, as is indicated by the arrows, the jets being directed generally toward a common point.

In accordance with the provisions of the patent statutes, I have described the principle of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof. It is to be understood, however, that the arrange- 1 nvention.may be carried out by such other means as come within the scope of the appended 'claims.'

, lVhat I claim as new and desire to secure by Letters Patent of the United States, is: 1. In combination, front, side and, rearhaving. a passage. for the admission of sec-- .walls. which define a fire box, said ,front wall a ondary air, a plurality. of injection nozzles.-

along the side walls of said fire box through .whicha fuel-air nnxture is supplied, said nozzles being inclined to thedirection of the axis of. the-fire box whereby they: impartlan inclined direction to the. fuel-air .mixture towards the direction of secondaryv air.

In combination, front, side and rear walls which define a fire box, said-front wall having a passagefor the admission of secondary air, channels along said side-walls through whichafuel-air mixture is passed,

saidhchannelsthrough which said fuel-air plurality of injection nozzles leadingfrom zles tomprizing a plurality of guide'vanes inclined towards the direction of the axis;

of said-fire box for imparting to thefuel air mixture an inclined; direction towards the. .direction of said secondaryqair.

In combination, front, side and rear mission of secondary air, longitudinal channels provided at saidside walls. having aplurality of slots, and a plurality of adjust-'- wallswhich define. a firebox, said. front wall .having a passage for the admission of secondary air, a plurality of injection nozzles handthis 5th day of October, 1929.

IVALTER 'KLEINOW. Y

as being connected together iii-groups by the v rods 1 5, wherebythey may be adjusted todirection as indicated by the arrows. In

Fig. El -they, are shownas beingadjustedto i discharge partly in. a forward .direction and

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