Патент USA US2131665код для вставки
Sept. 27, 1938. P. JORDAN ' ROTARY MUFFLE 2,131,665 ' FURNACE Filed ‘June 9, ‘1957 “ . 4 Sheets-Sheet 1 .7 a, . M‘MMMMAKIAQ \ . ' PAUL 4012 DAN by Ms a?orneys ' Sept. 27, 1938. P: JORDAN ‘ 2,131,665 ROTARY MUFFLE FURNACE Filed June 9, 1957 . - 4 Sheets-Sheet 2 Fig.2 a}Lava? 3/182 lnventor: PAUL. JORDAN 07 ms dfarneys' Sept. 27, 1938. - ‘ P. JOR‘DAN 2,131,665 ROTARY MUFFLE FURNACE Filed June 9, 1957 4 Sheets-Sheet 4 .ll llllHlH A\ n » \ PAUL Inventor: JORDAN Patented Sept. 27, 1938 2,131,665 UNITED‘ STATES PATENT OFFICE f 2,131,665 ROTARY MUFFLE FURNACE. Paul Jordan, Frankfort-on-the-Main, Germany, assignor to American Lurgi Corporation, .New York, N. Y., a corporation of New York ~Application June 9, 1937, Serial No. 147,332 In Germany June 10, 1936 15 Claims. ' (Cl. 263-34) This invention relates to rotary mu?le furnaces masonry of the furnaceshell two or more rows of of the type consisting of a mulile to receive the bricks projecting into the interior of the furnace. material to be treated and a shell carrying the On the side opposite the rowsof bricks, spring mu?le, the furnace being heated by means of ?re plungers or similar pressure-exerting means are ducts disposed between the muffle and the shell. provided, preferably likewise in multiple-rowed _5 The difficulties attending the construction and arrangement, which act on the mu?le and press it operation of such furnaces lie in the securing of it against the rows of bricks. The springplungers the mu?le to the outer shell, and the calking of are yielding, so that they will always hold the the internal mu?le against the ?re ducts, espe muf?e sufficiently ?rmly to preclude any dis cially in cases where the mu?ie is constructed of a placement relative to the shell,‘ but under heavy plurality of parts. Revolving muffles having their loading they can yield, preventing'destruction of walls sub-divided both longitudinally and trans the mu?le- by excessive pressure. Or, the plungers versely to the axis of the mu?ie, or longitudinally ’ or other yielding holding means are pressed thereto only, have already been constructed with againstthe muffle by springs which act between 15 the longitudinal joints of the mu?le supported the plungers and the furnace shell. 15 on bricks projecting from the masonry of the furnace shell. These bricks, usually wedge shaped. have also been provided with a recess for the reception of a lug formed from projections provided on the longitudinal edges of each mu?le segment. for calcination, they are not suitable for the melting of material containing metal, since the L joints could not heretofore be made tight against liquid metal. The lack of tightness is due to the differing amounts of axial and circumferential expansion occurring in the individual structural parts. When the furnace is heated up, the masonry in the iron shell expands more than the muffle inside the furnace. The bricks projecting inward from the furnace lining, which are intended to hold the mullie in position and at the same time to calk the joints where the muffle segments abut together by their ?rm hold on the projections on the longitudinal edges of the muf?e sections, recede more from the joints of the muffle seg ments, under heat expansion, than the muffle ap proaches under the expansion of its own bricks. Thus they are not capable of holding the pro jections of the muf?e sections tightly together at ' The main object of the present invention is to overcome this disadvantage, and this is accom plished by connecting the internal muffle, whether composed of a plurality of segmental parts or of one or more mutually adjacent tubular sections, directly with the shell by yielding parts, prefer ably in such wise that the muffle is brought into bearing with counter-bearing elements provided on the inner side of the furnace shell, by means of the yielding parts, which exert a thrust or a pull on the mu?‘le. 55 For example, there may be disposed in the ‘ ' Figure 1 is a section through a mu?le furnace according to the preferred‘embodiment of the present invention, taken along the line A—B of Fig. While mu?‘le furnaces so designed are suitable high temperatures. In the drawingsq 2; ‘ ' ’ - ‘ 20 Figure 2 is a longitudinal section through the mu?le furnace; ' " Figure 3 is a cross-section showing details of the brick arrangement; ‘Figure 4 is a longitudinal section through the same; Figure 5 is a plan view of the same; Figure 6 is a perspective view of a piece cut from the muffle furnace; . . - Figure 7 is a section through Figure 8 showing 30. a modi?ed brick arrangement; Figure 8 is a plan view of Figure '7; Figure 9 is a modi?cation of Figure 2; and Figure 10 is an enlarged detail of a portion of Figures 2 and 9. ' ' The mu?le' in. this example is sub-divided in cross-section into ?ve segments, as shown in Fig ure 1. The muflle may also be sub-divided per pendicular to the axis of rotation, so that two or 7 more tubular sections are formed, each of which 40 is composed of ?ve segments I, constructed for example of silicon carbide. The inner lining 2 of the iron furnace shell 2a is constructed of ?re clay or the like, and is provided with ?ve ribs made of preferably wedge-shaped bricks 3, 4, and 5. Between the shell 2a and the lining 2 there is also preferably provided a heat-retaining layer 2b, constructed for example of insulating bricks. The bricks 3 are preferably'equipped with shoes 01 0 3a, of silicon carbide for example, placed between the mu?ie and the bricks, to aiford the mulfle a broader bearing surface. To guard against dis placement of the shoes on the bricks, the con tact surfaces preferably have a dovetail form. 55 2,131,665 2 ner there are formed a number of compartments The bricks 4 and 5 are preferably held in the masonry, as shown in Figures 3, 4 and 5, by dis posing bricks 6 between the bricks 4 and 5 in each row; the bricks 6 are preferably also wedge shaped. However, the bricks 6 do not completely ?ll the space between bricks 4 and 5 in each row, but leave spaces ‘I free between them. The bricks 4 and 5 are of such shape that, in each row, the mutually confronting lateral surfaces of the bricks corresponding to the number of consecutive sec tions in the axial direction. The liquid metal present in one of the compartments of the fur nace can flow into the adjoining compartment only through the matched openings I3 in the abutting rims I4 of two sections or segments I2, and so long as no opening is lower than the sur face of the bath it will be con?ned to its own 10 compartment of the muffle. The height of the ?ange-like rims I4 and 10 4 and 5 are parallel to one another for one-half _ of the height of the brick. ' ' the depth of the cut-outs I3 can be determined to suit the kind and quantity of metal in the compartment. The mu?le segments I2 can be further reinforced with internal or external stiff In the space bounded by the parallel surfaces rise the projections 8a of the shoes 8. The shoes 8 are pressed against the internal mu?le by the 15 plungers 9, which are urged thereagainst by the springs II], the pressure of which may be adjusted by means of nuts or screw caps Illa. eners I5, which when internal serve also as turn ing devices and when external improve the heat absorption. The shoes 3a of the bricks 3 form the counter-bearings for the mu?ie, and the springs Iil insure that the 7 When materials or mixtures are treated which mu?le is always pressed against these counter bearings. are not required to be protected from contact 20 with ?re gases except at high temperatures, the The ?re ducts I8 are formed by pairs of ribs constituted of bricks 4 and 5, or 3 as the case may furnace can also be so constructed as shown in be, and by the muf?e wall and the lining of the part in an inclined furnace, serve as muffle fur nace, and the other part as direct-heated or com bination-heated furnace. In such case the heat drum shell. Figure 2, so as to have one part, say the lower The plungers can be further pro tected against overheating by a suitably resistant loose block I I. Instead of forming the ribs with the bricks 4 and 5, it is of course possible to make them of undivided bricks 33 provided with suit 30 able perforation or molded-in opening 34 as shown in Figures '7 and 8, so that instead of pairs of bricks 4 and 5 single bricks are: used. The num ber of segments and consequently of bearing o 35 within wide limits. The muille according to the present invention is distinguished by other advantages in addition to the reliable fastening to the furnace shell. It has the further considerable advantage that it passing through the lowest point still project The ?re ducts I8 may end over the highest pipe II as shown in Figure 9, so that the re moval of the gases takes place through the fur- » nace and the upper furnace-head. But as shown in Figure 2 it is also in many cases advantageous to pass one part of the furnace gases through the upper part of the furnace and toruse an other part for the external heating of the whole - other shaped pieces, and that nevertheless‘the joints, particularly those running parallel to the axis of rotation of the mu?le, are dependably tight against molten materials. 'In order to in sure the tightness of the joints circumferential to the muffle, additional special measures can be upper portion of the apparatus. The internal and external heating can also be effected in this applied if necessary. This also can often be dis pensed with, for example if the muffle is not sub divided longitudinally, or if fusion takes place in only one section of the muffle and the molten case by other heating media than those serving does not reach the circumferential joints. If sufficiently long mu?le segments'are used, it is possible in many cases, by suitably inclining the furnace, to avoid having any circumferential joint touched by liquid metal, that is to say, a metal bath is formed only in the lowest section of the muffle. drying section for the material to be treated. The pipes I‘! may be of heat and corrosion-re sisting metal or refractory material, and when plished. can be made of a large number of segments or 50 material inclined furnace which serves as preheating or beyond the level of the charge. With this ar rangement direct transmission of heat from the heating gas to the material treated is accom rows and of ?re ducts can of course be varied 4.0 ing gases may be led by means of pipes II, from the ?re ducts I8 of the mu?le into the part of the - But if the zone of fusion has to be greater than the possible or advantageous structural length for the heating of the muf?e. The length of the indirectly and directly heated ; zones of the furnace may differ greatly and will be adapted to the type of process being ‘carried on. If for example it is desired to reduce ma terial containing iron oxide to iron sponge or powder with the aid of gases, which are brought in‘ for example through the conduit or pipe 40 through the lower furnace-head and through the opening 2I, it will be advantageous to have the indirectly heated zone begin at the point where the reduction from F6203 to FeO is nearly or of a mu?le section, and if the calking of the cir-‘ entirely completed. 7 The reduction from FeO to cumferential joints against the ?re ducts offers special difficulties, it is possible according to the invention, in order to prevent liquid metal from penetrating into the ?re ducts‘, to use a special 65 form of muf?e segment which con?nes any pas sage of metal to those points of the circumfer Fe then follows in the indirectly heated part of ential joints which are located over one of the ribs formed by the bricks 3 or 4 and 5. For this purpose the sectional pieces of the muffle wall are plied, preferably in stages, through openings 36 distributed along the length, and advantageously made, for example trough-shaped. As shown in Figure 6, the trough-shape can be obtained by equipping the sections I2 on their circumferentially running edges with inwardly 75 extending projections or rims I4. In this man the furnace, possibly at higher temperature. The gases of reduction leaving the indirectly heated zone through the pipe section I'I shown in Fig ure 9 are burned in the directly heated zone, mainly in the upper part thereof, air being sup also about the circumference, of the furnace shell, and when so burned heat the charge to the necessary temperature. ‘ The lower furnace-head shown by way of ex ample in Fig. 2 can, depending on circumstances Serve for the-taking off of the metal, for the re 75 2,131,665 dium, etc., or simultaneously for'several of such said inwardly projecting portions,’ said'plungers and said portions having bearing parts, andshoes moval of residues, for the supply of heating me purposes or all of them. The metal flows'con tinuously, for example through the'opening's l9 pierced through a number of places in the lower end wall Isa, into the duct 20 in the furnace head, and which removes the metal by siphon action. If residues or slags are present which float on the metal, they can be brought out 10 through the pipe 2| into the down-pipe 22, through which they reach the bunker 26. On the down-pipe 22 is placed the bell or cover 23, hav ing a water trough 24 which forms a gas tight seal between the bunker and the open air. The 15 bunker 26 can be emptied by opening the sliding gate 25. The supply of heating medium to the ?re ducts of the muffle may be received through the pipe ‘2'! into the annular space 30, which is closed off from the furnace by the sliding surfaces or labyrinths 28, 29 shown in Figure 10, and is connected with the ?re ducts l8. The combustion air is brought into the ?re ducts by way of the damper-adjust able air nozzles 31. The muille in all its various possible embodiments can also lie horizontally. interposed between said muffle and‘ certain of said bearing parts. ' 7 -_5. Rotary mulile furnace comprising a mu?ie and'a masonry shell having inwardly projecting bricks forming bearings for said muffle, shoes en gaging said mulfle and carried by pairs of bricks, and plungers mounted between said pairs: of bricks and radially spring pressed against said 10 shoes. '6. Rotary muffle furnace comprising a mu?le and a shell having counter bearings, said mu?le ‘consisting of joined sections, and spring pressed plungers carried by said shell and urging said mu?le radially against said counter bearings and resiliently holding the joints together. > '7. Rotary mu?ie furnace comprising a muf?e and a shell having counter bearings, said mu?le consisting of joined sections having inwardly di rected annular projections, and resilient means carried by said shell urging said muffle against said counter bearings. . In particular, when so arranged, it can be oper 8. Rotary mu?le furnace comprising a muffle and a shell having counter bearings, said muflle ated by charges. The gas outlets can also be located at other points of the mu?le or of the ?re ducts, or even of the upper directly heated surfaces, and resilient means carried by said shell radially urging said mu?ie against said counter portion of the furnace. If the closure 4! in Figure 9 be opened, then gas will flow out of the muffle . at this point. In this way for example, a con tinuous operation of the muffle is possible. The muffle cross-section can be circular, oval, angular, or of other shape. This cross-section can be different at different points of its length. The mu?ie furnace according to the present ‘ consisting of sections having inter?tting joint bearings and thereby tightening said joints. 9. Rotary muffle furnace comprising a mu?ie 30 and a shell having counter bearings, and spring pressed plungers carried by said shell urging said mu?le against said counter bearings, said mu?ie having inwardly directed annular projections in- . terrupted at points where the muilie rests on said ' counter bearings. _ 10. Rotary muffle furnace comprising a‘ muffle invention has an exceedingly manifold ?eld of ‘ and a shell having counterjbearings, and yield application. For example it is suitable for the able means pressing said muffle against said 40 melting out of metals from ashes. drosses, and other materials containing metals together with counter bearings, the inner surface of said shell,‘ ‘I impurities; for the reduction of oxides to metal the outer surface of said mu?le, and the lateral surfaces of said counter bearings de?ning ?re with indirect and combined indirect and direct ducts for said furnace. . V heating; for the calcination and drying of mate 11. Rotary muffle furnace comprising a muffle rials which cannot be allowed to come into con having longitudinal ribs, and a shell having tact with heating gases at any but low tem counter bearings, and spring pressed plungers peratures, if at all; for the volatilization of ele carried by said shell and urging said mu?le against ments, e. g., metals, or of oxides and other com said counter bearings. pounds; for the effecting of chemical reactions, such for example as chlorination and the volatili zation of chlorides; and for other like uses. I claim: ' i 1. Rotary mu?ie furnace comprising a muffle to receive the material to be treated and a shell carrying said mu?le, said furnace being heated during rotation by ?re ducts disposed between the mu?le and the shell, and radially yielding parts associated with said shell and muffle for directly connecting said mu?ie to said shell. 2. Rotary mu?le furnace comprising a muflle to receive the material to be treated and a shell having counter bearings, said furnace being heated during rotation by ?re ducts disposed be~ tween the muiiie and the shell, and radially yield able parts pressing said muffle against the counter bearings. 3. Rotary mu?le furnace comprising a mu?le and a masonry shell having inwardly projecting bricks forming bearings for said mu?le, and radially spring pressed plungers carried by said shell urging said muifle against said bearings. 4. Rotary muf?e furnace comprising a muille and a masonry shell having inwardly projecting portions, and spring pressed plungers carried by 75 said shell for urging said muffle radially against 12. Rotary muffle furnace comprising a muffler constructed of heat and corrosion resisting metal, 5 0 a shell having a refractory lining with inwardly projecting portions forming counter bearings, and radially yieldable means carried by said shell pressing said mu?le against said counter bearings. 13. Rotary furnace comprising a muille and a shell having a lining and counter bearings, and yieldable means pressing said mu?le against said counter bearings, the inner lining of said shell, the outer surface of said muille, and the lateral surfaces of said. counter bearings de?ning ?re ducts, said furnace having a part constructed and arranged for direct heating and connected to said muffle, and means for passing heating medium into the interior of said furnace between said ?re ducts and said part constructed and arranged for direct heating and connected to said muifle. co 14. Rotary furnace comprising a muffle and a shell having counter bearings, and yieldable means pressing said muffle against said counter bearings, the inner surface of said shell and the outer surface of said muifle and said counter bearings de?ning ?re ducts, said furnace having a part constructed and arranged for direct heat- ‘ ing and connected to said muffle, means for sup plying heating medium to said ?re ducts at one 75 2,131,665 4 end of said furnace, and means for supplying combustion air at points distributed along the length of the ducts. ' ‘ 15. Rotary furnace comprising a mu?ie and a shell having counter bearings, and means press ing said mu?‘le against said counter bearings, said furnace have a part constructed and arranged for direct heating and connected to said muffle, said furnace having separated outlets for the re moval of solid, liquid and gaseous substances. UK PAUL JORDAN.