CA1099901A - Agglomerating process and apparatus - Google Patents

Abstract

AGGLOMERATING PROCESS AND APPARATUS

Abstract of the Disclosure The invention is directed to agglomerating apparatus in the form of a rotating drum and a method for agglomerating and controlling the size of carbonaceous material, such as particulate coal, finely divided char and, optionally, a binder such as pitch. Control of the agglomerate size dis-tribusion discharged from the drum is achieved by increasing the relative residence time of the small or growing agglomerates and by limiting contact between the large formed agglomerates and the small forming or growing agglomerates. The preferred means to insure adequate growth time for the small agglomerates consists of a plurality of annular ribs spaced about the inside wall of the drum and a cooperative scraping mechanism.
The scraping mechanism comprises a plurality of scraper blades projecting radially from a rotating shaft throughout the length thereof of the agglomerate-forming section of the drum. However, at the annular paths wherein a rib is found the scraping blades are shorter in length.

Description

1~99~1 Background of the Invention A. Coke Pellets Produced According to the Present Invention Versus Slot-Oven Coke for Blast Furnace Use This invention is directed to apparatus and a method for agglomerating and controlling the size of an agglomerating material formed in a balling or rotating drum.
More particularly, though not limiting in its application, this invention is directed to the agglomeration of carbon-aceous material to form pellets of a relatively uniform size.
When the pellets are formed and calcined, they may be used in place of metallurgical coke in the operation of a blast furnace. For convenience and to describe the further aspects of this invention, the description to follow will be directed to apparatus for, and a method of, forming such pellets.
Large quantities of coke are required annually by the steel industry for the manufacture of blast furnace iron, which, in turn, is converted into steel. Today, coke suitable for use in a blast furnace requires a mixture of high- and low-volatile coals (preferably having a low sulfur and low ash content) that is capable of being coked.
Furthermore, such coals must be coked in slot-type by-product coke ovens, which create serious air and water pollution problems. The present invention relates to apparatus and a method for forming relatively uniformly sized pellets of carbonaceous material which may be further treated to form coke pellets having characteristics that make them suitable for use in place of slot-oven coke in a blast furnace.

~k l`h~ ooke pellet~, or aEs~lomerate~ ~ ~ormed by incorporatlng into a co}ce-pellet proce~ th~ ag~lomera~ln~s method and apparatu~ de~crib~t~ ln ~he pr~nt inv~ntion have th~ aharac~t~ri~tic~ r~qulred ~or ~at~ ~at~tory ~una'clonirlg in a bla~t f'urnace . Tha~ 1~ 9 th~y su~)ply the nec~ary heat~nK
v~lu9 to the m~lting proces~ and 2ll!0 ~rong enough to uu~aln the ~urnaae burd~n, Th~ pellets r~taîn th~ir phy~cal inte~rity and r~si~t arum~ling~ 'cht~r~by permlt~lng the pa~8~g~ o~ th~ aBc~3ntlln~, hot gaB~ tl~ough the ov~rl~ring burd~n.
lna~much a~ the present inv~ntlerl d~al~ wlth th0 a~glom~ratlng ~tep ln a known pro~es~ ror mak~g ~OX~ p~
or ag~lomeratcs " ~t m~y be h~lp~ul to summarlz~ the g~n~ral characterlstic~ of' ~uch proc~s~.

B. ~en~ral Chara~t~rl~i u~ o~
a Proo~8~u fvr forming ook~ p~ t~ or ag~;lom~ra~s may be dsserlb~d in ~h~ ~ollowlng ~sen~ral t~rm~:
lo ~o~l~ wh~h 'cypioally may ¢~rl~ ~tl~ulato bituminuou~ cosl ~ho~e ~i~e ~ 73u~fi~1~n~ to pa~ through ~ ¦
4 mesh scree~n3 i~ pr~heat~d to Ju~t under i~ ~o~t~nlng t~mperatur~ be~or~ it i~ lntrod~ d wlth oth~r con~ uen'¢~
lnto an agglom~rQting drumO ~h~ oth~r ~onatitu~nt3 ar~:
ta) rinely divid~d ~har that ha~ b~en preh~ated to a t~mp~R-ture Or about 1000~1200F, and~ optionall;~ b) plt~h whioh f'unctlon~ prlmarily a~ a blnder to in~r~a~o ~h~ s~ n~5th oi`
th~ agglomer~s~ 'co b~ ~ormod ln ~he~ ag~;lom~ro,~ing drum.

"

9~L
~ . Th~ mlxkure o~ th~e oonstltu~nt~ -- warm partl~ulat~ ~oal, h~at~d char, and optionally pitch -- ~8 tran~ort~d into a balling OI' agglom~ra~ing drwnl. Pra heatin~ the coal ~nd th~ two okher re~d son~tltuent~ r~nd~r~
5 lt unn~c~ary to have ~ddil;lon~l or s~uppl~mental hea~ln~
mean~ in th~ agglom~ ing drum. That 1~, th~ Gon~kituento contain all of ~h~ heat requir~d to ral~e th~ t~mp~ra'cur~ o~
th~ coal abo~ it~ ~o~t~ning po~nt and thu~ cau~e the carbona~eou~ erlals to a~glomera'ce.
Durlng the agglomeraltiorl proco~ th~ a~lomsratlng drum i~ rotated to thorou~hly mix the coal ,, ehar, ~nd pi~ch and to tumble the a~glom~ratas a~ they are ~srmed. Durlng ths intimate mlx~ng o~ tha ~on~tltusnt~, the tamperELtur~ o~
~ th~ coal parkicl~s rise~ a~Y th~y re~eive h~at ~rom 'che 15 hi~her-temp~ratur~ char9 th~ r~ult b~ing p~rtial dis-tlllation o~ the coal partl~ such 'chat the agglomerate mat~rials ~o~ a loo~ly ~oherent pla~tlo EltiG~y mas3 in ~he agglom~ra~ing drum. In thos~ variatlon~ o~ ooke-pell~t proce~se~ that employ pltch a~ a blnder, tho pl'c~h ~ h~r 20 con~ribu~s to th~ ~gglomeratlon o~ the parti~ul~ on-3titu~nt~ wi~hin the agglomeratin~ drum.
3~ Th~ ~orm~d a6glom~rat~ ~ called "~sre~n agglomerat~s~ el, unhardon~dj T~hioh $xl~ ~rom th~
agglomerat~ng drum would, without furth~r proo~ g, 1AOk 25 ~ ~uf~ nt ~trangth to ~u~tai~ the heavy burden Or a oon~ i v~ntt onal bla~t rurna~e O Ther~ore ~ th~ ~reen agglomera~
ar~ subJ eGt~d to a ~lnal operatlon, whi~h i3 a ~lclnl~
I tr~tment at t~per~tur~s l~tw~n ~bout 1350 ~nd 1~00~.

"
' . . I

~hl~ tr~atm~nt imp~r'G ~ur.~ nt str~ngth and abra~lon re3istanoo to l;h~ p~ t~ or a~lom~rate~ to p~ lt th~lr u~e ~ n lieu o~ ~onventional ~ lo~oYon prodtlo~d blaa~ :~urn~e ~ok0 .
~h~ ~re~en'c irlventlo~ u~ on ~t~p 2~ ., th~
~ormlng o~ gre~n ~g~lom~rat~ or p~ ;8 ln ~n a~lomeratin~
(also call~a l'balllng" 3 dru~. A k~y ~ea~ur~ o~ thls i n~tlon . i~ tha~t 'ch~ a~lom~ra~lng drum ~nd as~so~lati~d ag~lameratin~ ~
methodt both Qr wh ~h will ba d.~ox~lb~d h~r~ 9 produca ~re~n a~glomorat~o or pell~ ha~ing a relatlY~ly u~ orm ~ize. Th2 relativ~ orsn~ty o~ 0 of a~lomerat~
. crltical irl in~urln~ the ~uco~E~ul op~ra~orl o.~ blao~G
~urn~¢e~ . In es~nc~" th~ pre~ent inv~ntion a~hi~ve~ ~hl~ ;
, deslred ~ize ~ontrol o~ th~ agglom~ratc~ through th~ u~ o~
15 a plurallty Or apaoed annul~r ribs lo~at~d on th~ lnalde w~ll o~ th~ agglom~ratlng ~rum tha~ coop~ra~ th a ro~cary ~cr~plng mechar~ whlch 1~ wlthin the ag~lom~rat~-rormin~
~ot~on o~ l~ho drum.
.1 C.

2û HaYlng au~marl~ th~ ~a~ntial ~ntri~l~tlon o~
the pr~a~nt lnv~ntlon a~l th~ agglom~rating ~t~p in a ~o~
p~ t proee~ t UB not~, ~or aomp~atlv~ pUrpOBO~, 'Ghe basic ~haraot2ri~ic~ o~ prior~ gglom~ratl~
Ag~lom~ratlng drums ar~ known E~ uoh ~truotu~ ha~e b~en em~loy~d ln oon~ tion with ~oraping dsvices ~ltuat~d within ~h~ drum ~ts~l;E . U.S. Pa'c~n~ No~ 'I
3,,31~,585 ~o ~al:Lb~r~ contain~ a ~ Q~U~e o~ 1;he u~
ro~ary s~rap~r po~itlo~l~d w~thln an ~e:glom;!sratir~s drum. ~ho I

I
" ~5_ 9~

scraper or scrapers are positioned within the agglomerating drum so as to remove agglomerative material from the inner wall of the drum and maintain a re~Latively uniform layer of the agglomerative material on the inside wall of the drum.
U.S. Patent No. 2,697,068 to Poindexter et al is another e~ample of a combination of a rotating agglomerating drum and a rotary scraping device disposed within said drum. In each of these two patents the scraper and drum apparatus are constructed so as to maintain a uniform layer of the agglomerative material along the inner wall of the drum.
In contrast to the apparatus of such prior-art, the present invention achieves more effective balling without having to maintain a uni~orm layer of the agglomerative material over the full length of the drum. The ability to work with a nonuniform layer results from the use of annular ribs or dams spaced at intervals around the inside wall of the rotating agglomerating drum of the present invention.
The manner in which such a drum wall configuration together with a cooperating scraping mechanism provides this ability and produces more uniformly sized balls or pellets is detailed in the specifications to follow.

Summary of the Invention The invention is directed to the apparatus and a method for agglomerating and controlling the size of carbonaceous material, such as particulate coal, finely divided char and, optionally, a binder such as pitch. When such carbonaceous material is heated and introduced into a rotating drum it forms into agglomerates. Control of the agglomerate size distribution discharged from the drum is achieved by increasing the relative residence time of the small or growing agglomerates and by limiting contact between the large formed agglomerates and the small forming or growing agglomerates. The preferred means to insure adequate growth time for the small agglomerates consists of a plurality of annular ribs spaced about the inside wall of the drum. The spaced annular ribs cooperate with a rotating scraping mechanism 'co maintain the radial depth of such ribs and to control the buildup of carbonaceous material between adJacent ribs. A scraping mechanism capable of` achieving such results has a plurality of scraper blades projecting radially from a rotating shaft throughout the length thereof of the agglomerate-forming section of the drum. However, at the annular paths wherein a rib is found the scraping blades are shorter in length.

Brief Description of the Drawings FIGURE 1 is a sectional view taken longitudinally through an agglomerating drum constructed according to the invention.
FIGURE 2 is a full sectional view taken along the line 2-2 of FIG. 1 of an operating agglomerating drum.
FIGURE 3 is a partial sectional view taken along the line 3-3 of FIG. 1.

.~

~ I~UR~ p~r~ial p~rsp~ctlve~ ~10w ~howing th~
inn~r w~3Ll ¢onrigur~tion an~ cooporatln~ sGraper m~hani~m o~ th~ agglomeratin~ drum o~ ~Ia. 1.

~ ~rred Embodlm~nt A~lom~ratin~ Drum I

Sin~ the critlcal ~e~tur~s Or th~ a~glomera~iLng drum Or th~ inven~lon ar~ ~h~ ~on~i~uratlon o~ lt~ lnn~r wall and the lnteraation of thl0 lrmsr ~11 with a ~ ping devl¢e, th~ro i~ no n~d ~o dascrlb~ m~ohanl~m~ ~or rota~in~ :
the drum an~ ~h~ s¢r~pine ~vl~. It 1~ ~uP~lG~n~ ~mp~g to point ouk that ther~ ar~ ~ariou~ kno~n mo~hanl~m~ ~or rotating the ~rum9 3~g., the Kallb~r~ pat~n~. Th~ pr~r~rred operatlon~ as ~hown in FI~. 2, 1~ to have th~ r~p~ct~
, rotation dlre~tion~ ~ounter to ono anothor, althou~h diroct~on and sp~d o~ ro~ation o~ th~ drum an~ s~raping ~chanlam m~y be ~ix~d or ~ariable dop~ndin~ on th~ mat~rlal~ ~o b~ ~h~rg~d into th~ drum.

, Annular Rlb B
Inn~ w~ll 12 i~ chara~terlz~d by ~ plur~ y o~
annular r~bs 16~ ~hlah are ~pa~ pr~rably at regular lnterval~, alon~ th~ l~ngth o~ drum 10. Rlb~ 16 ~omprl~ ¦
I ~te~l rlng~ or th~ llk~, wold~d or a~lx~d to the inn~r ; !
drum wall. Th~ r~ne~ ~un¢tlon æ~ a dam to r~tard th~
mov~m~nt o~ the l~maller ~nd~r~ d ~gglomerat~s in a ~on-tlnuou~ op~ratlon ~rom th~ "F~d Ena'l to khe "D~schar~ ~nd"
Or ~he drum and to limlt contaot botw~n ~h~ lar~r and ,! l 1~
0~

sm~ r a$~10m~rat0~ beln~ ~orm~d. Whlle FIG~ 1 ~hQw~ the rlb~ 16 to be ~venly ap~d along ~h~ druan, both th~ nwnb~r and spaclng o~ the rlbs can be varie~

Scraplng Assemb"l;~
~h~ s~r~pln~ as3e~bly 14 ~om~rl~ a rst~tlng ~craper aha~t 18 which 18 J ournal~d in b~arlng~ 20 ~u~
rotatlon in~ep~ndent o~ th~ rotatiom o~ the ~rum and ~o sets oi~ s~raper blad~ 22 and 24, rl~p~o~iv~ly, long ~nd : short. Serap~r ~lad~s 22 an~ 24 aro moun~d ~nd srr~ng~d along tho l~ngth of 5ha~t 18 in a plurality oP row~O
Typl~ally thore are ~our row~ ak right an~ to on~ ano~her;
oth~r po~sibl~ arran~em~nl;~ wlll be noted un~r "Modi~
j ~tlon~ 'co th~ Pre~err~d ~mbod~mont". The D~Jority o~ th~ I
blados in ~ach row ~re o~ 'ch~ loxl~r type, lab~lod 223 and, havlng a lan~th derlot~d by "X" 1 n FIa~3RE~ 2, 3 ~nd 4 .
Like~is~, th~ ~hort~r blad~, lab~l~d 24, h~r~ a l~ng~h d~not~ by ~yn. Th~ lollg~r blad-s 22 ar~ po~l1;ioned alo~g ~hart 18 in such ~ manner a~ to s~rap~ kh~ ~ntire lnn~r Il wall 12 of ~ am 10 betw~n rib~ 16. Eaoh o~ ~ha lon~;~r 20 ~ blade~ may ~o~r a ~p~:rat~ innor wall are~, but oth~
posslble arrangomsnt~ ~11 bo not~ lal~ar . Th~ ~shorter - blad~s a~ po~ltlon~d to ~crape 1;h~ top ~urPac~ o~ th~
rlb~ 16.

~ I
25 ~
A~ ~n alt~rnatllv~ to porman~tly ai;~rlx~ rlb~ ~o th~ ~r~Lm inn~r wall, ~he~ ~iaky ma~ ~orm~d by 'cho lr~
mi~lng o~ th~ hsst~d aoal9 ohar, and, optlo~ally5, pit~b I
1.
,1 _g_ .

may bo parmittod to bulld up on ~he ~nner wall alon~5 pra~
~eleoted ar~nular pa~h~ about; ~h~ inner wall . ~uoh path~
would ~oin¢ld~ wl~h 'chQ loca~ion Or ~h~ ~hor~r s~rap~r blado~ re ~u¢h buildup about the inn~r ~ p~r~ltg~d 5 to OGC~Ur, th~ maxi~um ~P~ctlv~ d~pth o~ ~uch bu~lt-up r~b~
wlll b~ l~mlted by th~ di~rer~nc1æ in l~rlgth ~tw~n th~ long and Bhort bl~ , b~ th~ ~autor (X ~
I~ requlred, rOr ~x~npl~ 3, to provldo long~r resld2na~ tim~ Or th~ r ~ro~lng agglomera~0~, ~h~
lO I long~r acr~per blado~ 22 can b~ r~pla~d by th~ ~hortor ~crap~r blad~s 24 ~ thu~ p~rmittlrlg a buildup o* the a~glo~nera-tl~ mas~ at th~ lo¢ation o~ ~h~ repla~ed bl~d~.

:~ Sara~er Assembly l~h~ blad~ 22 a~ld 24 m~y b~ arr~ng~d in ro~ ~u~h 15 that during rot~tîon the araa ~crap~d by ~ giv~rl blad~ may overlap th~ ~or~pin~ ar~a o~ ano~h~r blade o~ ~qu~l 10ng~h~
! or they may work ln tandem with ~nother blad~ 'co ~arape a common inn~r wall ~r~a. Finally~ th~ ro~r~ o~ . arap~r !I blad~ y b~ arra~g~ h~ s Qbsll~ th~ ~h~ 18 a~ a~
alternati~ to the parall~l arrang~m~n~ s3~o~n ~n ~IG. 1.

'rh~ prims ~on3tl~Gu~n~ ~dd~ ~co the drum ar~:
(1) partl~ulate aoal that has b~n pr~h~at~d to ~Wt Un~
it8 80rt8ning t~mperatuP~, (2) ~n~ly ~lvldo~ ~h&r ~hQt has b~n prah~at~d to b~twe~n 100~ and 1200 F" and ! (3) optlonally, a plt~h binder. Whll~ ~h~ qual~ty Or oo~
wlll ge~narally di~ta~ th~ r~la~Yo quantitl~ o~ ~on-~tituents ~d to th~ Qg3lom~rQ~ r~m" typl~allyg by 1, 1 w~l~ht ~ the proportlon~ ar~ lpartl~ulat~ coal 35 to 50% ~ char 50 to 65%9 and up l;o 10~ pltch. A3 a r~ulk o~ th~ pr~h~a~lng7 tar evolv~ ~rom th~ mixtur~ withln ~h~ drum, and tho mlxtur~
b~com~s a loo~ly ~oh~r~nt pl;el8t;.lC " ~!3tic:ky ma~s . A portion 5 1 o~ this pl~s~io ~ti¢ky m~ gtn~ l;o adh~re to the ~ur o~ the inn~r ~rall o~ th~ ro~atlng drum, To malntaln a unl~Qrm layer o~ the stiQky m~B b~1;we~n th~ anrlular rib~ o~
the rotatln~ drum, a scr~pln~ d~vlc~ o~ th~ typ0 ~on~l;ru~tod ac~ordlng to thls invent~on 1~ u3ad~ Wîth th~ tum~llng 10 1 act~on provi~d b~ th~ rotating drw~ and ~ontl~uou~ r~mova~
o~ portlon~ o~ th~ a lay~r by th~ ~raping d~ c~ ~ ~ald portions o~ the plast1~ part~ s ara ~o~ c~d lnto ~v~n larger agglomor~t~. 'rhe~ a~glom~rates ~on'clnu~ ~o ~row until the tar that ~volved ~rom th~ mlxture (ln~ludln~ th~
pitch blnder~ when add~d a~ a ~on~tituent) lo~e3 it8 pla~t1city, wlth the r~sult that th~ aggloalerat~s b~come rlgid or sti~ an~ ~5rowth c~a~s . ~h~ tim~ a~ wh~ ch thia plastlcity 1~ lo~t d~pen~ on the type o~ ~oal and th~
~ormlng temperat~ . For mo~t ool~ing ¢oal~ or ~oal mlx~s~ ' Il th~ 'cime to 1083 oP pl~tloi~y ~ould s.~ra~ lO ml3lut~ a1; ~ ¦
formlng t~mp~ratur~ o~ about 820 F9 ~th hi~h~r ~ormin t~mper~tur0~ pro~idin~ ~orre~pondln~ly ~h~rt~r tim~
Th~ ~ollo~in~ de~rib~ 1;h~ mann~r ln whl~h th~
~cr~ping meahanl~m operat~ to ln~ (a) an ad~qua~
. 5 r~sldano~ tlme withln th~ a~ m~rating drum rOa~ sur~iol~nt growth o~ th~ ~gglomerat~, and ~b~ the lim~tlng o~ ¢on~t~ nt adh~r~noe or buildup on th~ inn~r orall to a de~lr~d d~p~h, 1, , , . , !

~he lo~g~r ~ora~r blades 22, elth~r work1.ng with ~oraper blAd~ o~ th~ ~am~ or a di~r~rlt row, are arran~ed a~ou~
th~ ~orap~r ~ha~t 18 ~o a~ to ~o~ver th~ erlt~re ~rum lnnex~
wall betw~n adJacent rlb~ 16. ~he ~hort~r aor~er blade~ 21 overri~ ~he rlb~ 15 to maintaln ~he rib hol~h~ ~qual ~o th~
dl~ar~nce betw~n khe re~p~lv~ lengths o~ ~r~pffr ~lad~
che re~a~lon~hip ~xpr~30~ a~ ~X - Y~ . Xn ~ra~
ths ~mall~r agglomerat0~ tænd to ~sm~ntarily ~ttle be~oon ~u~h rlb~ a~ a rc~ult o~ th~ tumblinæ actlorl c wh~r~ th~
lar~r agglomerat~s tend ko rid~ above the rlbs~
Ag~lomoratlon ~ould be a contlnuou~ or batch-~ype op~ratlon. I~ th~ op~ratlon w~re aontinuouo, th~ lar~er ag~lom~rat~s would b~ ~poae~ to le88 tumblln~ than t;h~
small~r ag~lom~rat~ as th~y trav~r~ th~ drum, ~ive~a th~
311ght anglo (1 ko 2 from th~ hori~on~1) o~ the a~lom-aratlng arum dc~sendln~ ~rom th~ r~ end to kho d~ahar~
~nd .
~ln~lly, ~dequat~ r~b d~pth must bo provi~d ln ord~r to oontrol th~ ti~ during ~rhi~h th~ r agglom~ra~e~
20 ~ in ~on~b wl~h ~h~ r ~gglom~r~s. Othor~ o~
th~ lar~er a~lom~rato~ would t~nd 'GO c~nnib~ or a~mil~te th~ 3maller ona~ term~ o~ ~f~iv~ a~tlon, optlmum r~b dap~h i~ a func~Gion of ~h~ cnmbl~at1.on o~ ~gglom~ratin~5 !
d~ ;n and operatlng ~a~t~r~ th~t ~n¢lud~ ~rum ~i~o ~â b~d dapth Or burd~.
On 'ch~ b~si~ o~ ~x~erl~n~ ~Ith agglomoratin~
drum~, th~ fl~t b~ d~pt~ shoula ~ ~bout 20~ o~ t~ ~um dlamoter. Wh~n th~ drum 1~ rot~n~ l;h~ burd~z~ o~ growin~

aæglom~rates tend~ to ~pr~a~ out to .~orm a ¢onc~ve ~urrnco (FI~, 2 ) 3 th~reby ~:f ect~ reduclng th~ bQd t~pth to p~rhaps n~arly 10~ Or th~ drw~ diam~ter~ ~a~d then on ~h~
optimura b~d d~pth~ tha rib ~p~h ~Ihould ~ bOUt 4 to 12g o~
5 the dr~ d~ t~r. Thus; ~ ~p~¢i~ valuo ~or th~ or (X - Y) ~n b2 d~termln~d ror a drum o~ a glYen d~ r.
onGo th~ parti~ have a~ar~te~ and ~:rown ~alko agglom~rat~ ~th~ predomlnsLt~ Or whloh ~all~ withit j narrow r~nge~ th~ ~g~lom~rato~ aro ~thdra7~n f`rom ~h~
10 ; rotating drum, In a ¢ontlnuous opsrs.tlon 9 ~oa~l~urr~n$ w~h t he romov 1 o~ the alr~adg ~orm~d a~glom~rat0~ ~ addl'c~on~l rinely ~lvid~d ~arborlao~ou~ mat~er 1~ ~d r~ul~rly in~o thæ rotatin~ drum to ~p~at the ~ormln~ and ~rowlng pro~s.

~he o~otlv~n~s~ o~ the prer~rrsd op~ra~lon w~
demon~tratsd a~ ~ollow~ Y~ri~ th~ ~r~o~ivones~s o~ th~
r~bs ln ~on~rollln~s ~h~? a$glon~ra'G~ ~læo ~on~ 6 to ~th~r~ a narrow ra~ge, a batGh agglom~ra~ng ~tudy ~ on~u~t~d ! wlthout th~ U88 0:~ a s~rap~r Dl~h~nism but wlth 20 I, v~r~a~on~ in th~ srrlal hardware., The ~lo~oratlng t~t~ ~or thl~ ~tudy ~r~ p~P~or~
1~ a 36-ln~h diam~t~r ~rwsl:
) Wlth ~our row~ o~ r~k~ a~lxed ~o tho înn~r wall o~ ~h~ ~ru~"
(b 3 Wlth ~ivo a~nular rlb~ havln~ a r~dial ~p'ch o~
~our in~h¢~ evorlly ~pa~od about ~ lnnor ~all oP th~ drum, (c) Without any lnternQl h~rdw~r~ ,el ~ wlth4ut rake~
or rl~.
Th~ si~e-di~trlbution re~ult~ (T~bl~ I) dl~mon-s~r~ted ~ha~ control o~ th~ ~orma~ion o~ lax g~ lomera~
5 ' ~as b~er with ~h~ annular rib~ n wlth r~ke~ or ~i~hou'c : int~rnal h~rdware~ 1.
TABLE I. GOMPARI~30N O~ ~IZE-DISTRIBUTION CONTROI.
Av~raæ~ Av~ra~
Pl~dl~n S~
~ ~ize, Deviatlon, ernal Inch~ In~h~sx Har~ar~ ~ o .
(a) RoW8 oi~ }Rak~s 1~3~ 0.6~
~b) Annular R~b~ 0~87 0.55 15 ~ ~) Without Rake~
or Ribs 1.30 1i,04 Average madian ~lz~ d~terD~ned by ~or~2n sl~e ~chat ~B ~c~d~d by 50 w~ ght p~r~n'c Or the f`ormed ag~lomerat~
20 1 A~ ~ ~ dot~rmin~d by th~
dl~cr~nae b~tw~en th~ m~dian ~iz~ and th~
screen ~ 'shat ~c~d~ tll~ ~lz~ of ~ith~r 5.g or 84.1 ~. % o~ th~ ~orm@d ~gglom~r~ca~
50~ :~ 34.1%
U~lng (~ a m~ur~ Or th~ ~lze di~trlbll~ion o~
~gglom~rate~ tO not~s (1) ~lthout int~rn~l h~d~ 'ch~
a~;~lon~er~t~ size dletrib7ltion ~a~ qult~ larg~, and ~2~ ~l$h th~ annular rlb~ th~ a~lom~ra$~ alz2 dl~tributlon wa~ lo~rer than with th~ rate~ an~ much lo~r th~ wh~n no hardwar~
3 0 u~ed Th~ detall~d daga ~ro~ ~rhi~h Tabl~ ri~a~
. ~re list~d ~n T~bla II. For ~aoh t~, approxima~eïy ~u~l proport~on~ o~ K~yrord ao~l and ohar w~rs us~d~ Pit~h 1, , ,` ~

n ~ u~ th 10~ p~ 8 ~ r ~ h ru~, ~ch~ h ~ 7~S ~n~h~
~or~ P~ al~ h0 ~o~
w~ ~a~r~y ~t~ n~ w~a~n 7~3 an~

, TA~3LE II. AOaLOMERATIN~ T~S~

Rlln 1 2 F~ Compo~ition, _~
Co~l ~7, 3 4g~ o R~cyol~ Char52 . 751. 0 ~o~ C~ .
Forming Tlm~ O
minut~ ~5 ~5 ~orm~
l'e~p " o~
(at 5 min,)800 794 Coal Preh~at T~mp., F 608 611 Char Pr~h~at T~mp., }i 1123 1117 Cok~ Pellat ~iz~
Dl~tr~bution 9 -5" ~llt~ o. o _4~ ~31' o~o ~.
_311 ~lt 7~9 23.5 --2" +1--1/2 ~ 16 . g 35 . 2 . 4 ~6. 3 -1~ +3~41~ 11.4 8.o -3~tl 31 . ~ 6 . o -21' ~3~4t. 6~.7 6g.
x, M~diLan S1~e I
in¢h~ 1.15 1. 60 o, l~e~riation o~
~ize~, ln~h~ û . 72 0 . 60 TAE3LE II~ (Cont 'd) ~ r Rl~
Run 3 4 5 6 7 F~d Composltlon, Co~l 491~ 4g.0 49.8 49,g 119.9 R~y~le Char50 .1 51. 0 50 . 2 50 .1 50 .1 Fo~n~ Tlm~, minu~s 25 25 25 25 25 l~ormlng ~om~ F.
(at 5 ~ln.) 783 810 786 790 790 Coal Pr~h2a'G
~mp., F 611 ~or 610 611 610 Char Preheat T~mp ., ~F1120 1120 1119 1120 1120 Cok~ P~ t ~12e Di~tributlon g ~ .
51~ ~4n 12.8 0.0 0.0 0.0 0.0 _4~ ~31l 2.4 0.0 0.~ 0.0 0.0 ~3" ~2" 21.7 3.4 441 4.3 0.4 1/2n 1~3v5 6.11 13~0 ~.1 3.a 1~ 7 1~o2 ;~6~13 2~9 14~1 3/~ 3 15~3 L~0 19~0 L5~5 _3~4n 11~6 60.7 38.1 ~ 7 66.~

-2~t +3/41' 51 . 5 3!~ . 9 57 . ~ 53. 0 33. 4 Y, M~dian S~z~ ~
inah~ 1.65 0.50 0.90 ~B0 q.50 a" D~viation oa' ~i~e, in~h~ 0.40 0.75 0.3~ 0.7~ 0~,60 I - ~

~ g~
TA131.E ~ ont 9 d ) ~11;hout R~k~ or Rib~
Run 8 9 10 11 F~d Composition, Coal 49 . 7 50 ~ 0 50 0 49 7 R~cy¢l~ ChRr ~0.3 50,0 50.0 50~3 ~1~!
Forming Tim~, minut~ 25 ~5 25 25 Formln~
Tamp., F, (at 5 ~nln.~ 786 788 789 785 Coal Pr~h~at ~emp., ~F 610 611 611 615 Char Pr~h~at T~mp., ~ 1120 1120 1120 ï125 Co~s~ P~ t Di ~trlbu~ lon, ` -^5~ ~4~ 41~.8 ~.0 ~.0 O.Q
_4n 43n 13.1 1~7 3~5 2s9 ~31' ~2~' 7.~; 5.2 311.0 ~4,8 -2~ 9 . 5 13. 0 30. 0 2~
2~ 10.3 17,6 ~o~8 ~0~5

3/4~1 3.2 2~;.3 6.5 13.8 -3/4" 7.5 37.2 5~2 13.5 -21' ~3/4'1 23 . 0 55. 51 57 ~ 3 i~8 . 8 x, Modian ~
~nohes 3.4 1.0 1~75 1.45 a, DeY1~t10tl 0~
S~e, lnche~ 2.4 0.70 0.75 0.70 -~Lth ~30 prl~y pP~bl~ ng~3~ t~
k~ b~ ~h~ ~n~ o~ 3 th~
kil~ n ~h~ r~ u~ h~
oth~r kno~n oon~p~ ~o d~rælop ~h~ a~lo~
5 1 i~i8~ r ~ 0~ r~ n~
d~nin~sh t~ ivn or ~h~ lar$lsr ~lo~r~ s ~ r~y per~1~t~n~S ~ho ~o~n~l ~o~*h Or 3~11~11r ~æl~ a~o~O
O~h~ Yar~ o~ ~o ~ t ~or~d o~k~ p~ t~m~r~
lO I plt~h ~ddl~on, ~ o~s3lt~A~lon inr'o~st~o~ ~n ~o~b~ n ~ith ~h~ lio~o~ o~ l:h~
in~l~nkion ro~ th~ pro~UBl;ion 0~ a ~on~t~n~
~lo~nor~ t~ or ~n~ Lal ~llrp~
oolc ~or ~h ~t~ol lr~u-'cr~s bl6~ urruo-~.

Il --19'-i

Claims (8)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. Agglomerating apparatus to control the size of carbonaceous material formed into agglomerates in a drum, comprising:
(a) a drum rotatable about a central axis thereof, an exposed inner wall of said drum uniformly spaced from said axis throughout the length of said drum, and feed and discharge means for introducing and removing material therefrom, (b) a plurality of raised annular ribs affixed to said inner wall, (c) a rotating shaft extending into said drum, and offset from said central axis of said drum, (d) a plurality of scraper blades projecting from said shaft, where a predetermined number of said scraper blades are of a given length and adapted to scrape accumulated carbonaceous material from said inner wall of said drum when said drum and shaft are rotated, and (e) the remainder of said scraper blades having a lesser length, whereby said blades of a lesser length are interposed between said blades of a given length so as to scrape accumulated carbonaceous material from the top portion of said annular ribs about said inner wall.

2. The apparatus according to claim 1, wherein said annular ribs are formed by accumulated carbonaceous material within the respective planes formed by each of scraper blades of a lesser length as said scraper blades of a lesser length rotate.

3. The apparatus according to claim 1, wherein the raised annular ribs have a depth equal to about 4% to 12% of the diameter of said rotatable drum.

4. The apparatus according to claim 1, wherein there are a plurality of angularly spaced rows of scraper blades about said rotating shaft, each row containing scraper blades of said given length and said lesser length.

5. The apparatus according to claim 4 wherein said rows are parallel to the axis of said rotating shaft.

6. The apparatus according to claim 4 wherein said rows are arranged in helices about said rotating shaft.

7. A continuous method for agglomerating carbon-aceous matter in an agglomerating drum rotating about a fixed axis, and having a feed end, an inner wall, and a discharge end, the carbonaceous matter introduced into said feed end comprising finely divided particles of coal, char, and optionally pitch, a layer of said carbonaceous matter being formed on the surface of the inner wall and spaced apart annular ribs or rings of said rotating drum during processing, and continuously removing a portion of said layer to initiate the formation of said carbonaceous matter into agglomerates for exiting from the discharge end of the drum, characterized in that to insure that the majority of the agglomerates have a size within a narrow predetermined range, the residence time of the forming agglomerates is regulated within said drum to effect growth of the smaller agglomerates to said predtermined size, the relative axial speed of the larger and smaller agglomerates through said drum being directly proportional to their size, said formed agglomerates being removed from the discharge end of said drum while continuing to introduce new carbonaceous matter into the feed end of said drum the residence time of the forming agglomerates being governed by said spaced apart annular ribs or rings on said inner wall of said drum, each rib or ring being concentric with the axis of said drum.

8. The method according to claim 7, wherein the contact between the larger and smaller agglomerates is limited by said annular ribs.