EEE. eff 4S5. see-tail 17, ESS SY. 1,33,779. Patented Aug. 19, 1919, QO \SYU. O (at J, E, BELL, FURNA CE, APPLICATION FLED AUG, 7, 1915, N Es NE N

Transcription

1 J, E, BELL, FURNA CE, APPLICATION FLED AUG, 7, 1915, 1,33,779. Patented Aug. 19, 1919, HEE-HEET N E NE N Y. it i ae A i n N. 1 EEE. Y - 17, E eff 45 ee-tail () A er & it - it QO \YU. O (at 784%&é2eeze- NWentor 'No.

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3 J, E, BEL, FURNA CE, APPLICATION FED AG. 7, 195, 1,313,779. Patented Aug. 19, 1919, HEE-HEET 3. "I t. IR i.. J t A1 I, N. Marx Eie : WTNEE NWentOR 78.2% 44- R ye. Q t Qalwit, wiš

4 J, E, BELL, FURN ACE, APPLICATION FED AUG, 7, 1915, 1,313,779. Patented Aug. 19, 1919, 1 HEEi-HEET R w: w3 :VaM3 ;: '. : M : 2...: :.. C O t...' t NN E.; ; : *.*, :::::::::: *.i' E3:: F.....t.a : N-- tax 1. w R W N YNYY NN M N E. \ Š Y. N N N W 333 N N NN N NN N O. WNEE bar::::: NWENTOR :::::::: y 39 e.. &, Reviou Ok

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6 ,313,779. J, E, BELL, FURNA CE, APPLICATION FILED AUG, 7, Patented Aug. 19, 1919, HEE-HEET 6, A. W W WITNEE 78/7(7a-dee-eeee- g-eal/ NWENOR No. ti,\,..., &\ut, wavel

7 J, E, BELL, FURNA CE, APPLICATION FED AG, 7, 95. 1,313,779. Patented Aug. 19, 1919, HEE-HEE, I. t'', 2. w w WITNEE NWENtor 78.4%aet- R \\o.. Ace v , & Ot / aluva, Nv ww.k.

8 1,313,779., E, BEll URN ACE Application filed AUG, 7, 9 Patented Aug. 19, 1919, heer-heet 8. wrnee

9 1,313,779. J, E, BEL, FURNACE APPLICATION FED AUG, 7, 95. Patented Aug. 19, 1919, HEET-HEET 9, witnee NWendr 76%% ave-de- A t. f 22 a ely-&- Vy \\\vietu.

10 1,313,779. J, E, BEL, FURNACE APPLICATION FED AUG, 7, 1915, d Aug. 19, 1919, 1 HEE -HEET 0, Bet NY a Nge2ZZZZZZZ

11

12 UNITED TATE PATENT OFFICE, JOHN E. BELL OF NEW YORK, N. Y. EURNACE 1,313,779. pecification of Letter Patent. Patented Aug. 19, Application filed Augut 7, erial No. 44,198. ha hown that the capacity of both the To all whom it may concern: Be it known that I, JoHN E. BELL, a citi zen of the United tate, reiding at New York, in the county and tate of New 5 York, have invented a new and ueful Im provement in Furnace, of which the fol lowing i a full, clear, and exact decrip tion, reference being had to the accompany ing drawing, forming part of thi pecifi 10 cation, in which Figure 1 i a ectional elevation howing my invention applied to one form of boiler furnace. Fig. 1" i a detail ectional view of one 15 of the burner nozzle. Fig. 2 i a ection on the line II-II of Fig. 1, on a larger cale. ig. 3 i a view imilar to Fig. 1, but howing a modified form of the furnace and 20 a different type of boiler. Fig. 3 i alo a view imilar to Fig. 1, but howing a modification. Fig. 4 i a ection on the irregular line IV- IV of Fig Fig. 5 i a ectional elevation howing another form of my invention applied to a different type of boiler. Fig. 6 i a imilar view howing till an other form. 30 Fig. 7 i a imilar view howing till an other form, and alo illutrating a con trolling apparatu for the air. Fig. 8 i a ectional view howing till another form of the invention. 35 Fig. 9 i a detail ectional view of an other form of the primary mixing chamber. Fig. 10 i a vertical ection howing an other form of air and ga inlet nozzle, and Fig. 11 i a ectional elevation howing 40 another form of air regulator, the latter being hown largely diagrammatically. My invention ha relation to furnace; and while furnace embodying my invention may be ued for burning a variety of fuel, 45 uch a powdered coal, natural ga, or coke oven ga, it ha been more epecially de igned for burning blat furnace ga. At the preent time blat furnace ga i uually burned in ordinary boiler furnace, 50 the grate being either covered with a very low fire, or with brickwork. The ga, and part of the air py pae through burn er placed over the fire door, and an at tempt i made to mix the ga and air a 55 they pa through the burner. Experience burner and the furnace i limited; and a a conequence, it ha been neceary to ue relatively wide boiler, o a to provide ample area in the front for the placing 60 of the burner. Recent development in boiler work have, however, hown the E. marked advantage of boiler that are hig and narrow for ue with wate heat, or with fuel producing a low furnace temperature; 65 and it i thi type of boiler which hould be ued with blat furnace ga. When a boiler i fired by coal, a high tem. perature i maintained in the furnace, and a large proportion, amounting ometime 70 to a much a fifty per cent of the heat, E. direct from the fuel bed to the boiler eating urface by radiation. Under uch condition, the neceity for rapid tranfer of heat between the ga and the boiler heat- 75 ing furnace i not o evident. When, how ever, the proportion of heat aborbed by radiation i reduced, the defect of the boiler are magnified, and the deirabilit of the improved contruction i emphaized. 80 Radiation in a coal-fired furnace i largely from the fuel bed having a urface tempera ture of above 3000 degree F. If the radiat ing urface i reduced in temperature from 3000 degree F. to 2500 degree F., the heat 85 radiated i cut down to one-half of it for mer amount, and if the temperature be re duced to 2000 degree F. the radiation would be reduced three-fourth. The mean tem perature of the furnace now burning blat 90 furnace ga i coniderably below 2000 de gree F.; and a a conequence the radiation effect, a compared with what take place in coal-fired boiler, i practically negligible. It therefore, become neceary, when the 95 maximum economy i ought, to ue nar row boiler with a long pa, giving a high heat tranfer rate between the gae of com bution and the tube urface. It ha here tofore been impoible to do thi, on account 100 of the inability to burn the neceary amount of ga to develop the rated capacity. The criticim of the preent burner and furnace on account of their lack of capacity, i, how ever, really a minor criticim. The mot ob- 105 jectionable feature i the inability to burn the ga in the furnace.. ing a fuel ga running 105.B.T. U' E. cubic foot, a boiler of the tirling or ut type, having a tranfer rate of about 110

13 B.T.U., would, if the ga wa completely burned in the furnace with no exce air, "how flue ga temperature at a rating of from 500 degree F. to 575 degree F. Ac tual tet, however, of thee boiler how flue ga temperature from 700 degree F. to 1000 degree F. Thee high temperature come when an attempt i made to reduce the exce air, and follow from the fact that the combution i not then completed in the furnace, but i carried through the boiler; and the farther back the flame i carried, the higher the flue ga temperature. In the ordinary boiler furnace, the mixing neceary for complete combution cannot be obtained with natural draft. The ga may, however, be readily burned with a forced draft, and perfect combution ob tained with little or no exce air; and thi combution eem to take place almot im mediately. In the furnace of my invention, I take advantage of thee fact to inure a perfect mixture of the ga and a complete combution in the furnace at the maximum 25 obtainable temperature. Dut carried by blat furnace ga ha been detrimental to boiler efficiency, a it depoit on the heating urface. Thi trouble ha been o great a to make it deirable to wah 30 the ga before it goe to the boiler, freeing it a much a poible from dut. In doing thi, the enible heat of the ga, which i that correponding to a temperature of about 300 degree F., i lot. If thi could be 35 utilized, it would increae the available tem... perature of the ga ome 200 degree F., and would elevate the furnace temperature uf ficiently to how an approximate gain in ef ficiency of about five per cent. A further 40 object of my inventioni, therefore, to pro vide a furnace in which the ga can be burned without wahing it. Further, the ga i not delivered to the furnace at a uniform preure. By reaon 45 of variou incident of operation of the fur nace, the variation are over quite a wide range... Conequently, if the air upply to the burner i adjuted for one ga preure, a change in the preure diturb the ad 50 jutment, and a lo occur, due either to exce air or to imperfect combution. In my furnace I have provided mean to fur nih all the air for combution by a fan or blower, and to automatically caue the ga 55 preure to regulate the air upply. Thi can be done in variou way when a forced draft i employed, but cannot be practically carried out with a natural draft. Another advantage in the ue of a blat 80 over natural draft, i that it i poible to utilize, either through a recuperator or a re generator, a portion of the heat in the flue gae for heating the air upply. Thi i not, however, an economical propoition with 65 a boiler having a high tranfer rate, a the 1,313,779. flue ga temperature are then o low a to make the invetment in a recuperator or regenerator unremunerative. On account of the motion given the gae in my improved furnace, I have termed it 70 a vortex' furnace. In the accompanying drawing, I have illutrated everal embodi ment of thi furnace applied to different form of boiler. My improved furnace i alo applicable, however, to oaking pit, 75 heating furnace, hot tove, etc.' Referring firt to that form of my inven tion hown in Fig. 1 and 2, which how the application of the invention to an Edge oor boiler, the numeral 2 deignate the 80 furnace proper which, in hape i preferably an inverted truncated cone with a convex. top. It i preferably contructed with an outide teel plate 3, inide of which i a layer.4, preferably of magneia, and an in 85 ner lining 5 of firebrick. The teel plate hould be heavy enough to withtand the effect of internal exploion. By uing a layer of magneia of a thickne, ay, of three inche, with a firebrick lining of about nine 90 inche tivity of in the thickne, two may the be made combined ubtantially conduc equivalent to that of a firebrick wall thirty nine inche thick, and ufficient to withtand an internal temperature of from 2400 de gree F. to 2500 degree F. without exceive lo. At it lower end thi furnace, the in terior chamber of which form what I term the primary mixing and combution cham ber, open into a flue 6, preferably circular 100 and lightly inclined to the horizontal. Thi flue at it outer end open into the pace in the boiler etting which i uually allotted to the furnace, and which, with my inven-. tion, i preferably filled up with firebrick 05 checkerwork 7 to increae the radiation effect. The firebrick aborb the heat from the hot ga and radiate it to the boiler ur face. In thi form of my invention, I have hown the flue 6 a inclined downwardly away from the checkerwork 7. I provide a plurality of burner nozzle arranged around the top of the furnace o that a mixed blat of ga and air i delivered into the furnace chamber approximately tangentially to the perimeter of the internal urface of the furnace. The blat are ar ranged to act all in one direction. Any uitable, form of burner nozzle may be em ployed...in E.g. 1 and 2 I have hown the 20 a a coming from a upply pipe or main 8 rom which hollow connection 9 extend into the ga boxe 10 having the nozzle 11 communicating with the opening 12 which enter the furnace chamber tangentially i an air upply pipe urrounding the fur nace and having a connection 4 with an air box 15 at each burner, each of thee air boxe having a nozzle 16 which i arranged concentrically within the nozzle 11. The

14 O 5 90 O ,318,779 butle pipe 13 may be upplied with air blat ome uitable fluxing material uch a through the connection 17 having a con chalk, lime, or cruhed oyter hell, etc. trolling valve 18. In Fig. 2 I have hown The dut will not be entirely removed in the the boiler a having two of my improved primary mixing or combution chamber, furnace attached thereto, the two furnace but a the preure in the furnace force the being of correponding contruction, and ae out of the contricted neck 2 of the Ear pant being given imilar letter in urnace and through the horizontal connect 88C ing flue (the area of both of which are uch The burner nozzle are deigned to utilize a to caue the vortex motion above de part of the kinetic energy of the air. blat cribed) there i a trong tendency to weep in aiting the ga flow. The minimum the dut out of the gae and depoit it on area for the paage of both the ga and the the wall of the flue 6 where it collect in air in the paage i at the nozzle, o that the bath of lag (indicated at 23 in Fig. 1) the jet effect in the flow of a perfect fluid i which it i propoed to maintain in the bot approximated. The nozzle 11 i contricted tom of thi flue. Thi lag may be drained omewhat beyond the point of firt contact between the air and the ga, o that the air. by out mean from time of the to time lag into hole a uitable 24. Any pit. dut 23" jet can exert a uction action on the ga. which i carried through the flue 6 i depo From thi point of contriction into the com ited on the checkerwork 7 in the chamber bution chamber, the paage i gradually under the boiler. widened to obtain a partial converion of The urface of the flue forming thi ec the kinetic energy into velocity. For ad ondary mixing and combution chamber juting the ga upply, the air nozzle 16 hould, for the bet reult, be proportioned may be moved a a whole. For thi purpoe to the amount of ga conumed; or, more it i carried by leeve or drum 19 to which i properly, to the amount of dut which pae connected an adjuting wheel 20, thi leeve through the furnace. I prefer that the ur or drum being carried by the metal work of face area of the flue i uch that there will the air chamber. (ee Fig. 2.) The mov be at leat one quare foot of uch urface able air nozzle alo preferably carrie a con for one cubic foot of volume in the furnace trolling air plug or valve 21 which i epa chamber 2. rately adjuted, a by the hand wheel 22. By noting the direction of the vortex (ee Fig. 2.) Thee adjutment are not circle in Fig. 6 and 10 the trong centrif for cutting of entirely either the air or the ugal action (which I believe occur) tending. a upply, but are deigned to regulate to throw the dut out of upenion in the them with the leat poible lo of preure ga and caue it to be depoited in the man due to wire drawing. - ner decribed will be apparent. By collect The mixed air and ga will be delivered ing the dut in thi manner and preventing to the burner nozzle at a high velocity, it from depoiting on the heating urface which i preferably at leat equal to the criti of the boiler, raw ga may be ued without cal flow velocity thrpugh a circular pipe pf wahing. With wahed ga, the proviion that diameter. The purpoe i to provide made for removing the dut are unneceary, within the nozzle 11 and through the port but no modification i required in the fur 12, a well a in the primary mixing cham nace contruction, a the ame motion which ber and within the flue 6, a vortex or eddy remove the dut i alo a motion which it motion. Thi vortex motion at and beyond i deired to employ to mix the ga and air the nozzle i indicated by the dotted circle in a manner to inure perfect combution. in Fig. 10. The vortex motion in the flue By uing a furnace of thi E. blat fur connecting the furnace with the boiler et nace or producer ga may be burned with ting i indicated in a imilar way in Fig. 6. very nearly perfect combution prior to the Thi vortex action i believed to exit in all time the gae contact with the urface of the form of my invention hown. Thi rotary the boiler; and thi can be done with a or vortex motion not only inure a thor minimum air upply. Thi air upply may, ough mixing of the air and ga in a highly a hereinafter decribed, be controlled o effective manner, but it alo tend to caue a to automatically adjut it for change in a eparation of the dut carried by the ga, ga preure. I believe it to be poible in and to lodge it on the ide wall. The tem thi furnace to maintain a ufficiently high perature in the furnace i uch that thi dut temperature to inure the brickwork in the i in a fluid, or emi-fluid, condition, uch boiler etting underneath the heating ur that when brought in contact with a urface face of the boiler. to be at a temperature it will adhere thereto. It will be ufficiently that will radiate a material amount of heat fluid to caue the lag formed by the dut to to the boiler, and without fouling the heat flow by gravity through the primary mixing ing urface, even with raw ga. chamber into the connecting flue at the bot The furnace i adapted for ue with high tom. In the event, however, that the lag doe narrow boiler and, a above indicated, can not run properly, I may blow in with the air be employed for burning other fuel. It can '

15 14. 1,318,779 be ued either with or without air pre-heat form, however, not differing in principle ing mean. Wherever neceary, the wall from the form previouly decribed. It i of the furnace can be provided with water generally imilar to the form hown in Fig. cooled urface epecially in burning 1, except that the checkerwork below the powdered coal, natural, or coke oven, ga. boiler heating urface i omitted; and the 70 In burning powdered coal, it i believed that upper portion of the furnace i hown a ufficiently high temperature may be main having the water cooled top ring 36 pro tained to lag the ah, thu getting rid of vided with circulating connection 37 with one of the great difficultie heretofore exit the upper drum 38. Other part corre 0. ing in the ue of uch fuel. ponding to imilar part hown in Fig In Fig. 3 I have hown my invention a are given the ame reference numeral, with applied to a boiler of the tirling type. The the exponent 'c' added thereto. contruction of the furnace i ubtantially Fig.6 how a form of my invention in the ame a in Fig. 1 and 2, and correpond which intead of placing the furnace, otit 5 ing part in Fig. 3 are given the ame refer ide of the boiler etting, it i placed within 80 ence numeral with the exponent a ap the boiler etting and below the upper por plied thereto. I have, however, in thi view tion of the tube 39. The furnace 2 i imi hown the top of the furnace a having an lar inform to that previouly hown, being auxiliary air upply connection 25. I have placed between the etting wall 40 and 20 alo hown the top and bottom portion of opening at it bottom into the flue 6 which 85 the furnace a provided with the water i inclined upwardly to dicharge into the jacket 26 having circulating connection 27. chamber 41 below the lower portion of the The top jacket 26 may have a team pipe tube 39. connection 28 with one of the upper drum. Fig. 7 how another form of my inven of the boiler. tion in which the primary mixing and com 90 Intead of having checkerwork a in bution chamber 29 i located within the Fig. 1 and 2, it ha the vertical paage 30 boiler etting, the top wall 42 of thi cham communicating with the delivery end of the ber extending only partially acro the flue 6, and I may divide thi chamber by a chamber 43 in the etting. The mixed ga. 30 erie of vertical partition 31 et on the and air enter through a plurality of nozzle 95 upport 32 in order to give, in ome mea 44 at one end. The mixed air and gae ure, a checkerwork effect. The arrange are given the ame rotary vortex motion in ment of thee partition will be readily un the chamber 2 a in the preceding form, dertood from Fig. 3 and 4. I have alo in but intead of paing out in the retricted 35 thee figure indicated a ingle furnace end of the chamber, pa out around the upplying two of the flue 6 which branch roof arch 42. One of the main purpoe of from each other below the contricted open thi figure of the drawing i to illutrate ing at the bottom of the furnace proper. one uitable form of automatic regulator for Thee flue, a in the form firt decribed, regulating the blat in accordance with vari 40 contitute what may be termed the econdary ation in the ga preure. Thi form of 105 mixing and combution chamber. Fig. 3 regulator, or any other uitable regulator, alo indicate upplementary grate may be applied to any of the form of my coal-firing the boiler, although thee grate invention. In thi figure 45 deignate the are not ordinarily neceary. Thi arrange fan which upplie the blat pipe 46 having 45 ment i, however, ometime required by connection with the air boxe 47 of the noz. 10 boiler uer. zle 44. Thi fan i driven by the engine Fig. 3 how an arrangement which i indicated diagrammatically at 48, having yery generally imilar to that hown in Fig. the live team upply connection 49 and an 3, except that the flue 6 which form the exhaut connection 50. The pipe 49 ha a 50 econdary combution and mixing chamber control valve. 51, whoe tem i connected i inclined in the revere direction to that by the ytem of lever 52 with the tem 53 hown in Fig. 3. The uptake paage 30 of a bellow-like diaphragm, 54 having an i alo hown a having a lag pit 34 at the internal upply connection 55 with the ga bottom, into which the flue 6 may drain, main 56. The diaphragm 54 may have the 55 and which alo erve to catch any drainage counterbalancing weight device 57 con- 120 from the wall and partition in the uptake nected to the tem 53 by flexible connection 30. In thi figure the upplemental grate 58. The diaphragm 54 i placed within a for coal-firing are omitted; the boiler etting cloed chamber 59 having a pipe connection 35 i of omewhat modified contruction; 60 with the blat pipe and the water cooling ha been omitted from It will be readily een that the movement 125 the furnace. The latter i alo hown a of the diaphragm 54 will be controlled auto having a larger number of the inlet open natically by the preure in the ga main ing 12. Fig. 5 how the application of my inven 56 and that variation in thi preure will actuate the valve 51 to thereby control the 65 tion to till another form of boiler; thi engine 48 o that a the ga preure dimin- o 00

16 ,813,779 ihe the engine will be lowed down, and in the limit of temperature that a refrac a the ga preure increae the engine and tory ubtance uch a fire brick can with fan will be peeded up. In thi way the tand. When fuel uch a thee are burned, proper proportion of ga and air are main I line the inide urface of the combution tained. chamber completely with uch material. In Fig. 11 I have hown another form When, however, fuel uch a natural ga, of autqmatic air regulator. In thi figure by-product coke oven ga or powdered coal the part of the regulator are in general are ued a fuel the combution tempera imilar to thoe hown in Fig. 7, and cor ture, even with ome exce air, are higher 0 reponding part are given the ame refer than the commonly ued refractory mate ence numeral with the exponent 'g' added rial can tand, and when thee fuel are thereto. The eential difference i that the ued I make part of the lining of the com regulator, intead of controlling the engine bution chamber a water cooled urface. which drive the fan or blower, control a Thi urface may be formed by the lower 5 valve W located in the connection from the tube of a water tube boiler, a in Fig. 6, fan 45 to the blat pipe 468. or may be compoed of water tube connect In thi figure I have alo hown the air ed to the boiler o a to form a circulation and ga nozzle a dicharging directly into independent of the main circulation in the a mixing and combution chamber W. boiler, a hown in Fig. 5 and 8; or I may 20 The wall of thi chamber againt which ue a hell water cooled urface, a in Fig. the entering air and ga trike are given 9. The radiant heat falling on thee water the curved form hown at Y, whereby a vor cooled urface i immediately aborbed and tex action i produced, although to a ome the heat available for raiing the tempera what leer extent than in the preceding ture of the gae of combution i reduced. 25 figure. By the proper dipoition and proportion Fig. 8 how another form of my inven of area, therefore, of thee water cooled ur tion in which the furnace 2' i located within face I can limit the rie in temperature of the boiler etting in ubtantially the ame the refractory material forming the remain manner a Fig. 6. Thi arrangement i par der of the lining of the furnace to a ten 30 ticularly adapted for burning powdered perature lower than it fuing point. fuel. Each of the tangential inlet 12 for The advantage of my invention will be the air and fuel may be upplied by a hop appreciated by thoe killed in the art, ow per 61 through a uitable feeding device 62, ing to the greatly increaed efficiency re the air upply coming from the blat main ulling from it ue and having the regulating device I claim: deignate water cooling mean for the wall 1. A furnace of the character decribed, of the furnace 2. compriing a primary mixing and combu Fig. 9 how another form of the furnace tion chamber having a retricted outlet, in which the entire top 66 conit of a hol mean for introducing fuel into aid cham low water cooled member having the branched inlet connection 67 and the outlet connection 68. Fig. 10 illutrate another form of burner which may be employed. In the contruc tion hown hown in thi figure tha ga in let nozzle 69 ha the contricted portion at 70 jut beyond where the air and ga firt meet, the outer end portion 71 of the nozzle opening into the ga box i the air nozzle which i lidably mounted in the ca ing 74 and can be adjuted by mean of the wheel 75 and crew 76 to vary the amount of air entering the nozzle from the air upply connection 77. Movement of the nozzle 73, relatively to the nozzle 69, varie the inlet area of nozzle 69 proportionately to the change of the area in the air inlet. In thi manner the air and ga are properly regulated by the one adjutment, intead of by two eparate adjutment a in the pre ceding form. I may, however, ue any uitable form of burner. In burning fuel uch a blat furnace ga or ordinary producer ga, the temperature of combution, even with no exce air, i with ber mixed with air to produce vortex ac tion within the chamber, and a econdary mixing and combution chamber connected to aid retricted outlet and leading to heat ing apparatu, aid chamber being approxi mately circular in cro ection and extend ing in a generally horizontal direction, aid econdary chamber having mean for per mitting the removal of lag or dut there from, ubtantially a decribed. 2. A furnace of the character decribed, compriing a primary mixing and combu: tion chamber of diminihing cro ectional ducing area toward fuel mixed it lower with end, air tangentially mean for intro into the oppoite end portion of aid chamber, and a econdary mixing and combution chamber communicating with the lower end portion of the primary chamber and extend ing in a generally horizontal direction, aid chamber being approximately circular in cro ection and having mean for the re moval of accumulated lag and dut there from, ubtantially a decribed. 3. A furnace, compriing a primary mix ing and combution chamber having a re

17 6 1818,779 tricted contantly open outlet, mean for introducing fuel into aid chamber mixed with air, and a econdary mixing and com bution chamber connected to aid retricted 5 outlet, aid econdary chamber being in the form of a relatively long flue of approxi mately circular cro ection, heating appa ratu to which aid flue i connected, and a plurality of heat aborbing urface through 10 which the product of combution pa from the econdary chamber to the heating ur face of the heating apparatu, ubtantially a decribed. 4. Apparatu for burning blat furnace 15 ga, compriing a primary mixing and com bution chamber, a ga delivery nozzle ex tending tangentially into aid chamber, mean for upplying air to aid chamber, aid chamber being of gradually decreaing 20 cro ectional area toward it dicharge end, and a econdary combution chamber communicating with aid dicharge, aid econdary chamber being in the form of a relatively long generally horizontal flue 25 having wall upon which dut may collect and mean for controlling the velocity of the gae paing through aid chamber whereby the major portion of the dut con tained in the upplied blat furnace ga 80 will be depoited on the wall of aid ec ondary chamber, together with mean where by the dut, or lag produced thereby, may be removed from aid econdary chamber, ubtantially a decribed A furnace, compriing a primary mix ing and combution chamber having a re tricted outlet at one end portion, and fuel and air inlet opening at the oppoite end portion, mean for introducing air and fuel at a high velocity through aid opening to 40 create a vortex motion within aid chamber, and a econdary mixing and combution chamber into which the product of the pri mary chamber are delivered, aid combu tion chamber coniting of a flue of circular 45 form and extending in a general horizontal direction, but inclined from one end toward the other to give a lag dicharge, ubtan tially a decribed A furnace of the character decribed, 50 compriing a primary mixing and combu tion chamber having a retricted outlet ap proximately circular in cro ection, mean for introducing fuel into aid chamber mixed with air to produce a vortex action within 55 the chamber, and a econdary mixing and combution chamber connected to aid re tricted outlet and leading to heating appa ratu, aid chamber being approximately circular in cro ection and extending in a 60 generally horizontal direction, aid econd ary chamber having mean for permitting the removal of lag or dut therefrom, ub tantially a decribed In tetimony whereof, I have hereunto et 65 my hand. Witnee: EMERon G. HE, JEE. B. HELLER. JOHN E, BELL.