claim: l.'A boildr adapted for direct conn6ction with a kiln or furnace, for utilizing waste heat gases and products of combustion, including upper and lower water boxes connected bY downcomer tubes, lower headers co@mrnunicating therewith, upriaht tubes communicating with the lower headers, a supporting structure, and a lubricating plate on which the water boxes and the lower headers bear, said plate having passages, therein with openings extending to the surfaces on which the water boxes and headers bear, and a fitting to facilitate the introduction of a lubricant throtigh said passages whereby the wa-ter boxes and lieaders are supported with freedom to permit the same to rilove relatively to one another -@nder the influence of expansion and contraction due to temperature variations. 2. A boiler adapted for direct connection with a kiln or furnace, for utilizing waste heat gases and pro@ducts of combustion, said boiler comprising a steam drlim, a pair of spaced upper water boxes communicating with the drum at its opposite endsi a pair of lower water boxes connected with the upper water boxes' by respective downcomer tubes shielded by being enclosed in respective walls, a series of upper headers connecting said up-per water boxes, a plurality of sets of vertically spaced lower headers spanning the space between said lower water boxes and communicating therewith at different elevations, and respective sets of straight vertical boiler tubes connecting the said sei@eral lower headers with the said several upper headers, the vertical spacing of said lower sets of,headers being adapted to provide spaces between the alternate headers: of large area to fa6ilitate dust removal. :@ 3. A boiler adapted for direct connection with a kiln or furnace, for utilizing waste hea-t gases @Lnd products of combustion, said boiler comprising a horizontal steam drum, a pair of spaced water boxes with top walls inclined upwardly toward and communicating with the lower portion of the steam drum at its opposite ends, a pair of lower horizontal water boxes connected with said: upper boxes b respective straiglit vertical down@ y comer tubes shielded by being enclosed in re-

ulaper, .4pFi:@qRta al@ 4S VAKA'- QKPR s, e. ,th 4id- seyeK41 up .p.er ;kE@t6i@ li6xes, 'a' @iiii@lity of sets, of 4gri2Lo;ita -IlpgL4e@rs,,.@4e,,v ticpl@,sp i -bk,js er v qp 4,qed,lower 49@rizpi@t@l 4e4gpr ,, i?an4qg44@rs,,:4ping adap ed t @ , t o p y o v i d e ''be, @ -P -a,-ce -,bgt,w-een..said -_n t, r,,,.TAter, 5 *@,W@eq4 t4g! 4k@ernate,@4,pa(l(krs, pf.!,Ayge area janaa. cpr4irip@ii@Qgting.,therewith, 4pjltt;kte, c j4lT@F@l@t i@le lye@,se@ts,.,pf str@@gkit, y@.eXt@pl ,Q4RL-El@@STROUQUTBT. 1-Y

Patented Dec. 19, 1944 .1@ 2 1 3 6 5 3 0 5 UNITED STATES PATENT OFFICE 2,S65,305 WASTE HEAT BOMER Carl E. Stromquist, Griffith, Ind. Application January 24, 1941, Serial No. 375,862, Claims. (Pli:@22-7) My invention aims to provide @'a waste heaf st6am boiler specially designed for use in. conriection with cement kilns, with atcessory I apparatus for dislodging and disposing of dust c6ntained in,the.waste gas,@s. A I Ithough - particuiarly,appiicgble for use, in.connection with,dement kilns, the invention is, bf c6urse not restricted ther6to. Early in the development of the art of manut6 utilize the heat of the waste gases discharged from the clinkering kiln. These gases, being the -products of combustion of the fuel used in c alcining the,raw materials, compo@ed of limestone, clay, slag, etc., contain a 6onsiderable amount of dust evolved from the raw materials. This hot dust is tenacious or abrasive, or both, depending on the composition of the raw materiais used, and therefore tends to adhere to the boiler surfaces and also to wear away the metal at zones of high 20 velocity. Conventional types. of boilers and, apparatus used for generating steam by burning of fuel I directly under the b6ilers have been heretofore slightly altered in attempts to adapt them 25 for use as waste heat boilers. 'This resulted in considerable difficulty caused by the 4ust accumulation on the boiler surfaces, thus obstracting thp flow of gases, interfering with the draft, and bv dust -eventually wearing holos in the b oiler tubes, thus requiring costly premature replacements and 30 -repairs. BoiIers of the prior art that have previously been designed for wiiste heat service either lack certain essential features or contain certa@in objectionable @features and have therefore not 35 proven entirely satisfactory in actual service. My invention comprises specifle improvements on prior designs of wast@ heat steam boilers consisting of certain novel parts coinbiiied and ar-@ 40 ranged as definbd with particularity in the appended claims, to provide a workable installation which overcomes the above mentioned deficiencies which are inherent in prior art installatlions. The essential features bf :a succe@sful wa@te 45 heat boiler apparatus embodying the present invention will be readily understood from a consideration of the appended claims when read in connection with the following specification and, the accompanying drawings, in which: 50 Figure 1 is a longitudinal vertical view of the boiler (jugt inside of the brick sidewall) Figure 2 is a transverse vertical section tak&n ,along the plane of the line II--@-II of Figure 1; Figure 3 is a plan of front portion of the boiler; 55 Figilre 4 i@ an,eniarged longitudinal view of the lower portion of the boiler; Mgiire 5 is a transverse se I ction of Figure A taken along line V-V; !Figure 5a is a detafl,of a portion of the soot bl,owing apparatus; i c v i e w t a k e n f r o m t h e Vigure 6 is an isometr right end of Figure 1 showing, a , por ti , 6n of the economizer and illustrating the course of the wafactui,ing Portland cement, attempts were made:10 ter eir,culation. I To obtain practical and woikable results in the operation of a waste -heat boiler to be use.d in connecti6n with a dement kiln the principal . es@sential febtures embodied in my invention ate as @follows:@ First@--the utili.zatioii of 8trAight,vertical boiier tubes, economizer tubes, and superheater,tubes. This is to ptevent dust from lodging on the tubes, which in,.the dase of. the usual hokizontal or inclined tubes insuiates the upper area of the tubes, thus reducing the effective heating surface,, to prevent blocking the gas passages between adjacent tubes caused by dust accumulation in the form of bridges; and to elim,inate inaccessible dust pockets such as form in the use of bent tube 'boilers. .,Second-the provision of a sectional I tube hea@der. This is to facilitate the dislodgement of dust from the lower headers and to permit access to th,e entire area of aU tubes by means of laneing apparatus entered between the upper headers. .Third-the provision of means to induce a rapid water circulation. Water circulation is accelerated by means of downcomer tubes,, located outside of the direct gas passage. . This Provides a rapid equalization of temperature of all surfaces of the boiler corresponding with the deV61oped pressure when quickly subjected to the heat of the incoming gas discharged from the kiln, thus eliminating excessive strain from unequal expansion.@, This.also elizninlates local circulatio-,q within each individual vertical steam generating iube as in, the case with boilers not provided with' downcomer tubes outside of the direct gas @tream in which the rising steam bubbles restrict@ the dov@nward flow @of the water. Fourth-the provision of improved dust control apparatus. The usual type of: mechanical soot blowers are in@dequate for properly@dislodgin@ the dust in waste heat boilers used in connection with epment kilns. In @my invention special apparatus are provided to facilitdte control of and disposal of dust. Referring now to the drawings, in Figure I the numeral 10 r ; epresents a rotary cement kiln suP-

plied by pulverized raw rnaterial through the usual feed pipe I I and screw. conveyor 12. The h(>t dust-laden gases emitted from the kfln iinmediately enter the front end of the boiler passing between a plurality of front banks of steam generating tubes such as 13A, 13B, and 13C. In my invention the usual hot dust chamber is eliminated, which results in a great reduction of radiation losses. The hot dust emitted from the kiln 10, upon striking the comparc@tively cooler banks of,,b6ilet.@tl@b@ef 3,'ls qui6W f@-ediib'ed irf tdlfiperatur6 . "In'gtrikii@g the tubes 13','tli6 clil@t iiarticles, in horizontal motion, are instantly halted, turned in a downward direction, and strike ihei lower sectional headers 14 which are at,.the sarne. temperature as the tubes 13. After passing-down between the lower headers 14 into tffi@di@"ii 6fiiiinber 15, the dust has been cooled to@such-a, degree that the dust removal screw'co'n'veyors 16 'a're' not 2,365,305 tubes, 13, 13A, i3B, and 13C, the tubes directly opposite the kiln 10 are ornitted; (a) to pernlit access to the nose ring of the kiln IO, (b) to permit sudden expansion of the gases in leaving the kiln, and (e) to prevent injury tD such tubes when back rings in the kiln are being shot. In P-igure 1, the numeral 36 represents a laminated steel armor plate which is lowered into the gas passage in front of the tubes directly op@osite 10 the kiln opening for the purpose of protectin@y '-the'@tubes@lg"%V"n'-enbacle-iiii-ki-,I@ithe@kiiii'are being -@h6t,. zlee@io@@ble insi!@fig@:bY6c6 37 are pro,vided to cover the upper headers 31, 31A, 3II3, @,31C, etc., and alsd economizer headers 59, 59A, 15 - @@B -@ BSC;, etc. Thus the blocks seal the openings between the headers and also prevent radiation of leiit@ @r(>'M-@ @@he headers to the atmosphere. The blocks 37 are made removable for the purpose of 'fi'6i itating opera ion of soot bl "t. owing apparatus subjected to excessive temperdture. 'irhe@ 'du@i 20.@@ tG@@tb'be subsequently described. chamber 15 isipartitioned by@ removable cast iron I The bdiler -tubes 13, 13A, B, C, etc., are sepa-dr -i-6f radtor'y -bdffie'@s-'l idied @iii@6 f r6i!t',ai'd anic8 gr"o"u@ps'ilboth d, @bypassingthebanksoffiibi@@'@fT,. I e -,manner to@t e s V4@-r-ti@c'-A'l 8@id'o'- wtLll@, in- f -q@ to upp r a'li' lOWer",hoxders"aiid@'wgteV.'bbxes.@ 'The b'et'f5 @hd pre ere c the usual inclined or slo id-e's,- -wni'c'lf ('@,ld 'd-e -"ff" xidtum,38,bf th'e'b'o"ife,-r'@l'o'd'a"t' 25.8 ear @o '-@ign tgLuses'tlfe@'di)@t td"sride-@i@d orm a compact q ove, -be@iiks 6f ' 'oile@r' --tli ifito y tLn 6 mass that arches over the o-peiiihWl6ading: 'd, bdi@ll,e6tiid@@'bef*e6A th 'Id tllo @l. @'th , "V_ett cT&'d'bh conv on 6 dil@t. 66iiVeYbfs: c@'I it -am'ber,"a@i gliown @iii@Viddr @-t 2,' th@- a-'OuihultLte"d"ditst equipped with box. headers. e el gtaVitS, iiit6'-th6'ci@th gs ,and thi@ii,e -0 8,'on en s the'uljptr water to the conveyors. -1 6 without a. teiideh"dk to "form re6 "th6-,-obSe'dtioiUl' f " &iitiy df.sieb@ril-@fi6'til"th@ :@iitb I -8@l- -@'t,he diui@l -39 ' @"t t - .; I 6t @ I,, ,Iff'MgUr@,18 2 itid@.5':t5sh6;W@ trtitttiraT@'C@61 hi@ space'b een i I s 8 "1'4 @afi:d'rd*e'r@ W-'a't;"6'7-f'bdg"e'g"2'2. 3i t 'e b&ffbi thei- ii i"@'@a' e Immediately above the beams 21, as begt'gE5bii In' @-'6f '-tilb'@s 3 9, @iicls,-. "h-ea "M-gutd -a,- !tLbti'c@gtilf4'PlAt6i - 2'3 "@Cre'ln@@,tf@d'-Which "-iihrictbct int6,@tlie in'let@ d6i 46-oiitl@'i"@hdidei@'41 t-i' g i'6 6@ tfie"tt@@igtaKee "iib @l@e "n' -b'ok@e@s@ 4 -Tiib i @-t6'@ih'e" r 'h6riz6htal cte@Vfle dti@- "a9@ b64 dt,tiit@bs, jftgthe'e@iVaiigtoif ihtdr 'E41 'b@6rcr@' i@ifd alid '66fittaetr6n r6suf r' 40 tirig f r6ri vattation@' t,emp,,e@ratii,r,e,, th,e -s, 4'6"6'@d'd 6iigt'he'tELI@@@ebfgi shg@pe-cl"'sT,'e@'e-v'es -@hruii-k,'6n eeconoMiZe - and, ""@' 7 'ffi@@ns-- ar6"DtoVitl6'd'f or -'@hb i'bj'deti6ln bf @116- -t6 f-if 6ni@t -M "- @,i"hbatiiii6*s .. - sVdh,-ds t 'at - pre r ' brica'nt@'tltrbiigh-gftitE@bl" fii@iiies" 'j i f ei&b i eilli e r u e @ O i i 5 V i c l ' , @ d 1 * i t h connecting nipples 25 are expanded 45"O)tt@er@ffECI 6agtlrfi6tAl-@'pdcial@ ha'p-'6tl 9166#@s,-Shrfi'hiirito-the' loweP@'-heEea6r'g 14'-dtd 6r@. td,fit@ the"tUbes'.':@'@ -Th-b @@6ebiidriii2;di- 'dbWifddfAl@r accordance with the standard high pressufb @ofr6r "c'onstrtii@tiori.'@ Heqder"@"@,V'o"fts 2'8 undet'the altei i@iite@heddt@ie i 4' fdr'th.@" pi!@b6@@e"bf - tefaining the@irl 'A@- cc' hidhi@@ 'lf6r 1 whit@h" is-t 0"pro,Vid6,'drti$16'6peiiiilg8 f -'@ the !pA@s@ betvt6ii" tli6 zcham'b6r;15. @-li@'-th@.Idwer"#Et t&i@iiiiii6'92tz@sideves e@@ipaiid6d@' ifito -bdtli"sicfe*alli. 'I"' ,@27 @ato h6te lile6Vcis ,@blbVV6rs %1'04 to,b6@- @iib@edii6ntl@@@e@er'lb6d.@'-illitidti'tid "P'@"ovfde - ftir 'tlie'tabe.e 6ds"'bf "the'dothco!ni@t tli'e' cdnnecting@'nil)pIes@ - e @'With- similAr-haiia-hote@ -@igte@'2 9"f6f 'gdcb@@g t@o@'llie -' lbwef 6 -n@ds- o:f -tl-li 'the @steei @heathiiig'34- is filitti With iti@ul@tioii'3'@.".1ii ,Mgi@rb"2, -the: riu'ffe"r@'al-',30-'ili'e"pr'esen 'the up@6r 6.5 *ater, 6oiee@ - whf dh." -a 'r@e Is-@lupp@ @o' 'r'Wd @ f>@ tii6 'd6*@icomer tubes 29. "Th&luo6f s"e-c'tio'n' al'te'ade'r-s'-31 are supi@brted'bi'fhi3'-@t6Aiil'g6iief@ifi@e-t'u" V6@ 13 pp. and-d6ri@e'ct6d'.toth6u er- 'itd-r;'boxiFs 30 -bN@ the :thi@'r6@;sdii ',I- , 1) @, i,', -23."'@Iteli'dd6ts4-'f4"'drle'liioVf&ed 6o @@ple materia;ls for the pu pose,will ,be provi ed :eirculating,tuV6gr(R @and -L) @ 5 I-'a'ie siifiili@i@,tb'the -b6ilei',- d@6wricariiei@ tu)se@,,,29f "The?4ed6rf,6triftir -,,@vater b6xe8 (R- 'and,,L)1,-52,.%Iare constrileted;siihrO,fil@Eirl@y t6,the'I6wdr,bbiler @water, bo-k45s@,22--,biit@,dre - provided,,with, baffles, (@R arid,,L) --&3t, 53A,@,@-3B; et',,., to create contraflow of gas and water.through -the economizer-.@- :.Th-e- upper- economizer,wgter .-i)Dxes @5 are -prov@ded With-,baffles@4-6,,55 ete.,@ having. leakl,holes.A,7,,jRA,,qT)3,. ete.,,topre@"vent -air, binding. -Provision- is rna@le. for -varying ii-ie size qf @the:leak hQles@ 3-,; ptc-.1@.by,the, use of an adjiistable valve mechanism. Wherc,, corrosive water conditions prevail, suitd in the canstrtiction, of the-,economizer.. n' c from the,lwn end 6ig:th@ first c@@- @, ..- I @.. e@@t en o e- econom water boxes,52 through the stop and c alves,. ,O,, he .connO(!tng@ni'p'ple@s-32'..@-'-;' 70 " "t"- wa er pressurl, b'e@i ing",@ 'n'e@ce's'sarily' m' E-@intained t h i l n i i i 6 @ i 6 s " s - u r - e 1 -'2 'and 3 three or more upper SOME@w.hat'@reatei devpoped etl c.-I'alr'e'- i'n"'@tWo 11. 11 t - fie' b6ile-t. -,"-Tbe"b'a"-ffle@"s' (R'' 'an"d-,.t in 53 i eflect the wa f er 'thro'u@'gh' t-.h' -.e i -owe@Tr- 'c -o'n"nee in@g nipples '@bblffotis 'iind@liorte,iied'td@p;r@o"v"id-O"-an' @o'-p'e -ni:@'f6r t r@l the-raw feed pipe I I and the manl@616"rjra'm-"e's"35. "@A thb i6*6i fi@id'e,-i tB'-, 'It'th6n 'In thfee---.-ot- ihore@ioW@-@dt'tt@,6 @t@e'a'm'@g'e'n"'-ting 75 flo*g ui) through the-row ick h-e'ari'iik

@'2;365,305 'thouPPtr'header'59"thro-ughtheupper'conif6eting nipples (R and L) I 6 I @ into th e firs co,mpart Went of the upper'water boxes (R, and L) 55.. The b@affle8, (R and L) 56 deflebt the water throu@h ''the downcomtr tubes (Rand:L), 51 and SIA, into '-5 the first and second dbmoartmi@nts, re@pebtively, 6f- the lbwbr 6ohifoctihg- boxes 52. The portion of the water descending through the downcomer tubes (R and L), 51 re-enters the lower header 58 through the connecting nipples (R and L) 54 10 and recirculates upward through the heating tubes 50. The'portion. of the water desctnding through the downcomer tubes (R and L) 5 1 A into the second compartment of the lower water boxes (R and L) 52 passes through connecting nipples 15 (R and L) 54A and 54B into headers -58A and 58B, then upward through heating tubes 50A and 50B, into the upper headers 59A and @59B. The water in the header 59A passes through connecting nipples (R and L) 6 1 A into the first compart- 20 ment of the water boxes (R and L) 55, through downcomer tubes (R and L) 5 1 A and recirculates. The water in header -59B passes through connecting nipples (R.and L) GI B into the second compartrnent of the water boxes (R and L) 55 and 25 into downcomer tubes (R and L) 51B and 51C. The w@ter in downcomer tube 51B recirculates through the lower headers 58B and heating tubes 50B. The water in downcomer tube 51C enters the third compartment of the lower water boxes 30 (R and L). 52 and tllrough connecting nipples (R and L) 54 irito headers 58C, then up through heating tubes -50C into header 59C. The water eircuiation tl-ius continues successively through the remaining sections o.f the economizer until it 35 leaves through the economizer outlet pipe 62. The above described means for recirculation of water in an economizer is a novel arrangement which greatly increases the rate of heat transfer over the conventional type of economizer. 40 The baffles 56, 56A, 56B, etc., are provided with respective bypass openings 57, 57A, etc. which may be terrned leak holes which are effective to prevent vapor bindin.- in the upper economizer water boxes 55. The water leaves the economizer 45 through the outlet pipe 62 as shown in Figure 1. The required amount of water to maintain the proper level in the boiler is fed through the pipes 62 ahd 63 (Figure 1) and the feed water regulator 64 into the boiler drum 38. With the boiler 50 in normal operation, since the incoming water is of a lower temperature than that in the boiler, it will immediately flow down through the downcomer tubes 29 into the lovier water boxes 22 (which are ew-bedded in the boiler wall as shgwn 55 in Figure 2), thence through the lower connecting nipples 25, headers 14, into the steam gen-. erating tubes 13, upper headers 31 and upper water boxes 30, where the steam bubbles are drawn towards the drum 38 and liberated into 60 the steam space. The circulation is continudus through the individual sectional header@ and corresponding downcomer tubes, thereby always maintaining a positive directional flow equivalent to the natliral thermal acceleration produced -by ,j the upward force of the steam bubbles formed i,,i the steam generat.ing tubes. In a(idition thereto, the lower water boxes provide for adequate equalization of pressure throughout the entire boiler. -to The steam lewiin-. the drum 38 passes throtigh a separator 65, thence through the separator outlet pipe 66, superheater inlet header 40. tubes 39 and the usual stop and check valve 67 to the steam main. The economizer, boiler, and super- 5 'heater ..are equipped. witli@-converitional' saf'ety v alves qs indicated at 6,8, 69, and 70 iii Figuies 1 ai@d @2. Tile g s travel'is . in a single pass, Impinging a on t I he.front bank of the steam genetatirig tubes 13, t@e superheater tubes 39, the rear bank of the boiler t@ibes 13, and the economizer, tubeq 50, thence discharged through the induced draft fan 71. In installations where the dust conditions permit, baffles are inserted between certain rows of tubes in the rear zoiie of -the b(>iler and.in the economizer to increase gas velocity. 'Also, where dust conditions permit, the tubes are staggered so as to attain maximum heat transfer. Means originally disclosed herein for dislodging dust and soot on the boiler heating surfaces are clearly illustrated, described and claimed in my Patent No. 2,358,358, issued September 19, 1944, which is a division,of the present case. Althoiigh I have described with -great particularity certain characteristic features of the embodiment of the invention herein. illustrated, it is not to be construed that I am limited thereto, since various changes in arrangement and substitutions Olf equivalents may be made by those skilled in the art without dep-arture from the invention as defined in the appended claims. I