Control of the grain size distribution of the raw material mixture in the production of iron sinter

Transcription

1 SAIMM_57-64:Templte Joul 6/9/08 11:55 AM Pge 293 Cotol of the gi size distibutio of the w mteil mixtue i the poductio of io site by E. Lwmb* d A.M. Gbes-Cig* Bckgoud T s c t i o Syopsis The im of this study ws to exmie the effect of gi size distibutio cotol of the w mteil mixtue o the pemebility of the gee site bed d the popeties of the poduced site. This ws chieved by evlutig the gultio chcteistics of the site mixtue (moistue cotet, gultio time d me gule dimete) i tems of its gee bed pemebility, d evlutig the poductivity of the site bed, the coke te, tumble idex (TI), bsio idex (AI), eductio disitegtio idex (RDI) d educibility (RI) of the poduced site. The w site mixtues cotied combitios of Thbzimbi io oe, Sishe io oe, coke, lime d etu fies. The gi size distibutios wee cotolled by emovig the 0.5 mm size fctios of the etu fies d coke, d the 1 mm size fctio of lime. Of the exmied mixtues, mixtue of 20 mss% Thbzimbi io oe, 80 mss% Sishe io oe d fluxes whee the coke, lime d etu fies wee ll sized hd the highest gultio effectiveess d pemebility. The siteig popeties of the mixtues i which the gi size distibutios wee cotolled, wee vey simil fo ll the mixtues, but supeio to the bse cse mixtue i which the gi size distibutio ws ot cotolled. Keywods: Thbzimbi io oe; Sishe io oe; gultio, pemebility, gi size distibutio; site. Itoductio I the mjoity of poductio pocesses, the pticle size distibutios of the w mteils ifluece the popeties of the poduct. This lso petis to io site, which is costituted of mixtue of w mteils (io oe, coke beeze, limestoe, lime, dolomite, etu fies) ll of which hve vious size distibutios. Although AceloMittl Vdebijlpk hs fixed specifictios o the physicl d chemicl popeties of the poduced site fo optiml blst fuce pefomce, the pticle size distibutio of thei site mixtue hs ot yet bee optimized. The mi pupose of this study ws theefoe to exmie the effect of pticle size distibutio cotol of the w mteil mixtue o the qulity of the poduced site. Oly limited mout of fie io oe pticles c be diectly chged to the blst fuce, s they e detimetl to the pemebility d gs flow distibutio i the blst fuce, d c eve be lost i the off-gs1. Fie oes theefoe udego iitil gglometio though siteig o pelletiztio, befoe beig chged to the blst fuce. Duig gglometio though siteig, the w mteil mixtue fist goes though gultio pocess. I this pocess the io oe fies, coke beeze, limestoe d etu site e mixed with wte d tumbled i oty dum. Itemedite d fie pticles (the dheig pticles) the cot the cose pticles (the ucleus pticles), though ite-pticle dhesio vi wte bidges, wheeby lge gules o qusi-pticles fom. These qusipticles e lge i size d owe i size ge th the oigil feed2,3. A potio of these qusi-pticles lso educe i size, due to bekge d ttitio. The oute shell of the qusi-pticle is theefoe ctive duig gultio, s it is costtly bekig dow d e-depositig4,5. Vious uthos defie the sizes of the ucleus d dheig pticles diffeetly: ccodig to Begstd et l.6 the ucleusfomig pticles e typiclly +1 mm, while the dheig pticles e -0.5 mm i size, while Khos d Muel7 epoted the dheig size fctio to be -0.1 mm. Fomoso et l.8 defied the ucleus of the qusi-pticle s beig +0.7 mm, with the dheig fies s mm. The ole of pticles i the itemedite size ge is still ot completely udestood: Liste d Wtes showed tht icesig * Deptmet of Mteils Sciece d Metllugicl Egieeig, Uivesity of Petoi, Petoi. The Southe Afic Istitute of Miig d Metllugy, SA ISSN X/ Ppe eceived Nov. 2007; evised ppe eceived M P p e The Joul of The Southe Afic Istitute of Miig d Metllugy VOLUME 108 REFEREED PAPER MAY

2 SAIMM_57-64:Templte Joul 6/9/08 11:55 AM Pge 294 Cotol of the gi size distibutio popotios of dheig mteil deceses the gultio effectiveess, but decesig the size of the dheig pticles iceses it9. Loo d Pey howeve, showed tht eplcemet of oe by oe tht cotis highe level of itemedite pticles ( mm) c impove pemebility10. Wte dditio, pticle size distibutio, oe poosity, sufce popeties of the io oe d wettbility of the io oe by wte e the most impott fctos tht ffect the gultio efficiecy d pemebility of the gee site bed The pemebility of the site bed i tu cotols the poductivity of the site plt, s well s the micostuctue d popeties of the poduced site, s the gs flow te though the bed goves the tempetue pofile though the bed. The pocess i which qusi-pticles fom is vey stogly iflueced by moistue tht is vilble fo gultio13. Sub-optiml moistue dditio deteiotes gee bed pemebility pidly6. The mout of moistue equied fo gultio vies widely with oe type10,11,14. Khos d Muel foud tht the optimum moistue could be descibed ccutely by kowig the SiO 2, LOIT d Al 2 O 3 ( 1 mm) cotet of the oe, s well s the 0.15 mm d pecetge of itemedite ( mm) size fctios7. Fo most io oes, icese i pticle size close to the 0.1 mm size ge hs the getest effect o educig pemebility d icesig the mout of moistue tht is equied fo gultio7. The use of diffeet size fctios of coke beeze d flux i site mixes hve bee studied15 17 s well s the use of cose io oe pticles10,18,19. Bhgt et l.15 epoted tht the micopoosity of the site d its educibility icesed with decese i the size ge of the coke beeze. The eductio disitegtio idex (RDI) decesed, the educibility decesed mgilly d the poductivity icesed whe the size ge of the flux ws owed dow fom 3 mm to mm. Hosoti et l. epoted tht the simulteous emovl of the 1 mm limestoe fctio d the 0.5 mm coke beeze fctio impoves the gultio idex d pemebility of the gee site bed16. This led to suppessio i the shikge of the site cke, icese i siteig te (d theefoe poductivity), s well s impoved educibility due to icese i the umbe of fie poes. Ksi et l.17 exmied the ifluece of the use of usized d sized coke fies d limestoe o the peigitio pemebility s well s the pemebility of the bed duig siteig. They foud tht the use of lge pticles of coke d limestoe esulted i impoved pemebility befoe d duig siteig. The pemebility of the poduced site cke lso depeded lgely o the pe-igitio pemebility. This idictes tht some spect of the stuctue of bed of gulted site feed is coseved duig siteig. Teo et l.4 epoted tht lge coke (+1.0 mm) d flux (limestoe d sepetie) pticles did ot ppe to pick up fie pticles well. Fie coke pticles c oly be icopoted ito the dheig fies lye whe thee is ledy dheig lye peset fo them to imbed i. They hypothesized tht coke is poo gultig mteil, eve i the uclei size fctio (+1 mm), due to its hydophobic sufce popeties4. Loo d Pey10 epoted tht cose, poous io oe bsobed wte d educed the level of fee wte vilble fo gultio, but impoved the pticle size distibutio of the gulted mix. Two-stge cotig gultio pocesses hve lso bee ivestigted with the itet of impovig poductivity d educibility of the site4,20,21. I these pocesses ceti tget qusi-pticle stuctue ws chieved though divided flux dditios, usig two gultio dums. These pocesses did ot lwys dd beefits to the popeties of the poduced site. Expeimetl Rw mteils The w mteils used i the siteig expeimets wee Thbzimbi io oe, Sishe io oe, etu fies, coke, lime, qutz, wte d feic chloide (FeCl 3 ). The followig bbevitios e used to descibe the exmied smples: 20 d 80 (50 d 50) with fluxes: mixtue of 20 mss pe cet Thbzimbi io oe, 80 mss pe cet Sishe io oe (50 mss pe cet Thbzimbi io oe, 50 mss pe cet Sishe io oe) with fluxes ot sized (C d L): coke beeze d lime sized (C d L d R.F): coke beeze, lime d etu fies sized. The pticle size distibutios of the lime d coke beeze tht wee used e give i Tble I. The etu fies wee sized by emovig the 0.5 mm size fctio. Gultio d pemebility The ifluece of moistue cotet d gultio time o the pemebility d me gule dimete ws studied i the ges of espectively 2 8 mss pe cet d 2 10 miutes. A dum, with dimete of 51.5 cm, height of 50 cm, t costt ottiol speed of 26 ottios pe miute, ws used. Te smples of 10 kg (dy bsis) of ech w mteil mixtue wee used. The pocedue ivolved vyig the moistue cotet of the mixtue while keepig the time costt (5 smples), fte which the effect of gultio time o pemebility t optimum moistue cotet (5 smples) ws exmied. Afte gultio pt of the gulted smple (ppoximtely 4 kg) ws used fo pemebility test. A test pptus, m i height d m i iside dimete, ws used to mesue the pemebility, which ws expessed i tems of the Jpese Pemebility Uit (JPU) ccodig to¹¹: whee: V: iflow te (Nm3/mi) A: e (m2) H: height of the bed (mm) ΔP: suctio pplied coss the bed (mmh 2 O) Tble I Pticle size distibutios of the coke beeze d lime (mss %) mm mm mm Coke beeze Lime MAY 2008 VOLUME 108 REFEREED PAPER The Joul of The Southe Afic Istitute of Miig d Metllugy

3 SAIMM_57-64:Templte Joul 6/9/08 11:55 AM Pge 295 Cotol of the gi size distibutio The pemebility ws clculted by tkig the vege of 3 mesuemets of pessue dop fo diffeet flow tes t the vetui, t the top d t the bottom of the test pptus. Sieve lysis A potio of gulted smple ws foze with liquid itoge, i ode to pefom sieve lysis o the gules, wheeby the mteil tsfe betwee gulometic clsses (by compig the size distibutio befoe d fte gultio) ws studied. This ws doe by plcig g of gulted mixtue o metllic ty, fte which liquid itoge (-200 C) ws poued o the gulted smple d o the scee. The gulted smple ws cooled togethe with the scee i ode to void deteiotio of the gules duig sievig. The gule size distibutio ws detemied by weighig the cooled fctios etied oto diffeet scees fte 5 miutes of sceeig. The esults obtied e peseted o semi logithmic gphs, whee the odite (ithmetic scle) shows the gi o loss s pecetge of the totl smple weight, d the bsciss (logithmic scle) shows the gultio clss. Ech poit epesets the diffeece betwee the qutities of mteil befoe d fte gultio fo ech gulometic clss. The followig pmetes wee detemied22: X: The size limit betwee the educed d icesed gulometic fctio duig the gultio pocess expessed i mm, cosideig tht the educed d icesed gulometic fctios e the fctios whose eltive pecetges espectively educe o icese fte gultio. The vlue of X is obtied fom the itesectio of ech cuve with the x-xis of the semi logithmic gph. S: The level of mteil tsfe betwee the educed d icesed gulometic fctios, expessed s pecetge of the totl weight of the smple. Ex: The efficiecy of elimitio of the fctio smlle th X mm, duig the gultio pocess. S d Ex e clculted fom: S = (%<X mm) BG - (%<X mm) AG = (%>X mm) AG - (%>X mm) BG Ex = 100*S/S, whee S = (%<X mm) BG, d (%<X mm) BG = the weight fctio of gis less th X mm i the mixtue befoe gultio, d (%>X mm) BG = the coespodig weight fctio bove X mm. (%<X mm) AG = the weight fctio of gis less th X mm i the mixtue fte gultio, d (%>X mm) AG = the coespodig weight fctio bove X mm. Siteig Site tests wee cied out t Kumb Io Oe pilot plt i site pot with coss-sectiol gte e of 0.16 m2. Fou site mixtues, idetified s the optiml mixtues fte gultio, wee ivestigted: Mixtue I: 50 d 50 (C d L d R.F), with 5.5 mss pe cet moistue Mixtue II: 20 d 80 (C d L d R.F), with 4.5 mss pe cet moistue Mixtue III: 20 d 80 (C d L), with 4.5 mss pe cet moistue Mixtue IV: 50 d 50 (C d L), with 5.5 mss pe cet moistue. The compositios of these 4 mixtues e give i Tbles II d III. T s c t i o P p e Tble II Compositio of mixtue I (mss %) Rw mteil Mixtue I Thbzimbi io oe Sishe io oe Retu fies Coke beeze Lime Dolomite Silic Wte Feic chloide Tble III Compositio of mixtues II IV (mss %) Rw mteil Mixtue II Mixtue III Mixtue IV Thbzimbi io oe Sishe io oe Retu fies Coke beeze Lime Dolomite Silic Wte Feic chloide The Joul of The Southe Afic Istitute of Miig d Metllugy VOLUME 108 REFEREED PAPER MAY

4 SAIMM_57-64:Templte Joul 6/9/08 11:55 AM Pge 296 Cotol of the gi size distibutio Expeimetl esults Gultio d pemebility The pemebility of both the 20 mss pe cet Thbzimbi io oe: 80 mss pe cet Sishe io oe mixtue, d the 50 mss pe cet Thbzimbi io oe: 50 mss pe cet Sishe io oe mixtues icesed s sized fluxes eplced the usized fluxes, d eched mximum whe ll the fluxes (coke beeze, lime d etu fies) wee sized (Figues 1 d 2). Whe the moistue cotet i the gulted mixtue ws vied, while keepig the gultio time costt t 6 miutes, mximum pemebility of 49 JPU ws chieved fo the 20 mss pe cet Thbzimbi io oe: 80 mss pe cet Sishe io oe, sized coke beeze, lime d etu fies mixtue, t 4.5 mss pe cet moistue. Whe the ifluece of gultio time ws exmied t optimum moistue cotets, the pemebility of the 20 mss pe cet Thbzimbi io oe: 80 mss pe cet Sishe io oe, sized coke beeze, lime d etu fies mixtue ws icesed to 51 JPU whe the gultio time ws decesed to 4 miutes. The optimum moistue cotet d gultio time fo the 50 mss pe cet Thbzimbi io oe: 50 mss pe cet Sishe io oe, sized coke beeze, lime d etu fies mixtue wee espectively 5.5 mss pe cet d 6 miutes (Figues 1 d 2). The sme ted ws obseved fo the me gule dimete (Figue 3): The biggest gules fomed whe the mixtue 20 mss pe cet Thbzimbi io oe: 80 mss pe cet Sishe, with sized coke beeze, lime d etu fies wee gulted. The vege me gule dimete of the mixtue 20 mss pe cet Thbzimbi io oe: 80 mss pe cet Sishe io oe chged fom 2.4 mm befoe gultio to 4.4 mm fte gultio whe oly the coke d lime wee sized, d fom 3.0 mm to 4.8 mm whe ll the fluxes (coke, lime d etu fies) wee sized. Vitio i mteil tsfe betwee gulometic clsses The vitio i mteil tsfe of the w mteil mixtue with fluxes betwee gulometic clsses, fo diffeet moistue levels t 6 miutes of gultio e illustted i Figues 4 to 9. I the mixtue 50 mss pe cet Thbzimbi io oe: 50 mss pe cet Sishe io oe with fluxes ot sized, fie pticles hve dimetes smlle th 0.48 mm d cose pticles hve dimetes lge th 1.8 mm (Figue 4). Whe the coke d lime wee sized, the dimetes of the fie pticles wee smlle th 1 mm, d the cose Pemebility (JPU) Me dimete (mm) Time (miutes) Figue 2 Ifluece of gultio time o pemebility (moistue cotet fo 20 d 80 mixtues is 4.5 mss pe cet; moistue cotet fo 50 d 50 mixtues is 5.5 mss pe cet) Moistue (%) Figue 3 Ifluece of moistue cotet o the me gule dimete of the diffeet io oe mixtues with fluxes (gultio time of 6 miutes) Pemebility (JPU) Loss o gi (%) Fctio (mm) Moistue (%) Figue 1 Ifluece of moistue cotet o pemebility of the diffeet io oe mixtues with fluxes Figue 4 Vitio i mteil tsfe betwee gulometic clsses fo the mixtue 50% Thbzimbi d 50% Sishe with fluxes ot sized. (H = moistue cotet) 296 MAY 2008 VOLUME 108 REFEREED PAPER The Joul of The Southe Afic Istitute of Miig d Metllugy

5 SAIMM_57-64:Templte Joul 6/9/08 11:55 AM Pge 297 Cotol of the gi size distibutio pticles lge th 2.9 mm (Figue 5). Howeve, whe ll the fluxes whee sized, fie pticles hve dimetes smlle th 2 mm d cose pticle hve dimetes lge th 3.35 mm (Figue 6). I the mixtue 20 mss pe cet Thbzimbi io oe d 80 mss pe cet Sishe io oe with fluxes ot sized, fie pticles hve dimetes smlle th 0.9 mm d cose pticles hve dimetes lge th 2.9 mm (Figue 7). Whe the coke d lime wee sized, fie pticles hve dimetes smlle th 1.4 mm d cose pticle hve dimetes lge th 3.35 mm (Figue 8). Whe coke, lime d etu fies wee ll sized, fie pticles hve dimetes smlle th 2.4 mm d cose pticle hve dimetes lge th 3.35 mm (Figue 9). Gultio potetils of mixtues of Thbzimbi d Sishe io oes d fluxes The esults o the gultio potetil of Thbzimbi d Sishe io oes d thei mixtues e summized i Tbles IV to IX. The gultio potetil of give io oe mixtue is bette th othe oe if its pemebility d the mout of mteil tsfe (Ex) is highe t optimum moistue cotets, d lso if its moistue cotet (H) is less. The vlue of S idictes the mout of mteil tsfe i mss pecetge d the vlue of Ex shows which fies e elimited effectively. D(B.G.) d D(A.G.) e espectively the me dimete befoe gultio d fte gultio, expessed i mm. I compig the gultio potetils of mixtues cotiig 50 mss pe cet Thbzimbi io oe d 50 mss pe cet Sishe io oe, the mixtue whee the coke d lime wee sized (Tble V) peset bette site mixtue th the mixtue whee the coke, lime d etu fies wee sized (Tble VI) d whee the fluxes wee ot sized (Tble IV). Although its pemebility is slightly less th tht of the mixtue whee the coke, lime d etu fies wee sized (44 vs. 45 JPU), it pesets highe Loss o gi (%) Fctio (mm) Figue 7 Vitio i mteil tsfe betwee gulometic clsses fo the mixtue 20% Thbzimbi d 80% Sishe with fluxes, ot sized. (H = moistue cotet) T s c t i o P p e Loss o gi (%) Fctio (mm) Figue 5 Vitio i mteil tsfe betwee gulometic clsses fo the mixtue 50% Thbzimbi d 50% Sishe with oly, coke d lime sized. (H = moistue cotet) Loss o gi (%) Loss o gi (%) Loss o gi (%) Fctio (mm) Figue 8 Vitio i mteil tsfe betwee gulometic clsses fo the mixtue 20% Thbzimbi d 80% Sishe with coke d lime sized. (H = moistue cotet) Fctio (mm) Fctio (mm) Figue 6 Vitio i mteil tsfe betwee gulometic clsses fo the mixtue 50% Thbzimbi d 50% Sishe with coke, lime d etu fies sized. (H = moistue cotet) Figue 9 Vitio i mteil tsfe betwee gulometic clsses fo the mixtue 20% Thbzimbi d 80% Sishe with fluxes, coke, lime, d etu fies sized. (H = moistue cotet) The Joul of The Southe Afic Istitute of Miig d Metllugy VOLUME 108 REFEREED PAPER MAY

6 SAIMM_57-64:Templte Joul 6/9/08 11:55 AM Pge 298 Cotol of the gi size distibutio Tble IV Gultio potetil of mixtue 50 mss pe cet Thbzimbi, 50 mss pe cet Sishe with fluxes ot sized Smple Smple Smple Smple Tble V Gultio potetil of mixtue: 50 mss pe cet Thbzimbi, 50 mss pe cet Sishe with coke d lime sized Smple Smple Smple Smple Tble VI Gultio potetil of mixtue: 50 mss pe cet Thbzimbi, 50 mss pe cet Sishe with coke, lime d etu fies sized Smple Smple Smple Smple Smple Tble VII Gultio potetil of mixtue 20 mss pe cet Thbzimbi, 80 mss pe cet Sishe with fluxes ot sized Smple Smple Smple Smple Tble VIII Gultio potetil of mixtue: 20 mss pe cet Thbzimbi, 80 mss pe cet Sishe with fluxes, coke d lime sized Smple Smple Smple Smple efficiecy of elimitio of fie pticles (Ex = 76.2% vs. 59.7%). The gultio potetil of the mixtue with 20 mss pe cet Thbzimbi io oe d 80 mss pe cet Sishe io oe with fluxes whee the coke, lime, d etu fies wee sized (Tble IX) ws the highest with pemebility of 49 JPU, high efficiecy of elimitio of fies (Ex = 86%), d high level of tsfe of fie pticles to cose pticles (S = 50%). Siteig The qulity of the poduced sites wee evluted d comped with the cuetly poduced site (clled the Bse Cse ) i which the site mixtue cosists of 50 mss pe cet Thbzimbi io oe, 50 mss pe cet Sishe io oe d usized fluxes, to which 5.25 mss pe cet moistue is dded duig gultio (Tble X). The site popeties of 298 MAY 2008 VOLUME 108 REFEREED PAPER The Joul of The Southe Afic Istitute of Miig d Metllugy

7 SAIMM_57-64:Templte Joul 6/9/08 11:55 AM Pge 299 Cotol of the gi size distibutio Tble IX Gultio potetil of mixtue: 20 mss pe cet Thbzimbi, 80 mss pe cet Sishe with fluxes, coke, lime d etu fies sized Smple Smple Smple Smple Tble X Compiso of the site popeties of Mixtues I IV with those of the Bse Cse site Mixtue I Mixtue II Mixtue III Mixtue IV Bse Cse Poductivity.(t/24 h/m2) Coke te. (kg/t.site) Yield (%) Siteig time (miutes) TI (% mm) TI (% mm) AI (% -0.5 mm) RDI (% mm) RDI (% mm) RDI (% mm) RI (%/mi) T s c t i o P p e Mixtues I IV wee foud to be vey simil, d supeio to the Bse Cse site, with the exceptio of the TI (% mm) d the RDI(%-0.5 mm) i cse of Mixtues II d III. The poductivity d yield ws impoved whe sized fluxes wee dded to the site mixtue, while the coke te, siteig time d AI(% -0.5 mm) wee educed. Noe of the sites (icludig the Bse Cse site) cofomed to the citei of RDI (% mm) i excess of 70% d RDI (% -0.5 mm) of less th 5%. All the exmied sites cofomed to the equiemets of TI (% mm) > 70 pe cet d RI 1 pe cet pe miute. Site Mixtue IV hd the shotest siteig time (20.1 mi.), the highest poductivity (33.8 t/24 h/m2), good RI (1.2%/mi.), the highest RDI (% mm) (66.7%) d the lowest RDI (% mm) (5%), d is cosideed to be the best of the exmied sites. Mixtue II hs the highest yield (83.93%) d lowest coke te (79.4 kg/t.site), d is cosideed to be the secod best site mixtue to Mixtue IV. Coclusios The pemebility ws the best t y gultio time fo the mixtue tht cotied 20 mss pe cet Thbzimbi io oe, 80 mss pe cet Sishe io oe d fluxes whee the coke, lime d etu fies wee ll sized Whe ll the fluxes wee sized, lge gules wee fomed comped to whe oly the coke beeze d lime wee sized As wte dditio icesed, the pemebility icesed d the gultio effectiveess impoved, esultig i the fomtio of lge pticles. Howeve, whe wte dditio ws icesed beyod the optimum vlue, bed pemebility d gultio deteioted The gowth i me gule dimete duig gultio is fuctio of the iitil me dimete befoe gultio, the mout of moistue, d the gultio time. As the time icesed, the me gule dimete icesed up to ceti vlue d the stted to decese The emovl of the -0.5 mm size fctio of coke beeze, -0.5 mm size fctio of etu fies d -1 mm size fctio of limestoe, s well s the use of highe popotios of Sishe io oe, icesed the size limit (X) betwee the educed d icesed gulometic fctios The me gule dimete does ot pedict the pemebility of the bed The mixtue of 20 mss pe cet Thbzimbi io oe, 80 mss pe cet Sishe io oe with fluxes whee the coke, lime d etu fies wee sized d the mixtue 50 mss pe cet Thbzimbi, 50 mss pe cet Sishe with fluxes whee oly the coke d lime whee sized hve the best gultio potetils The site popeties of the fou sites, i which the gi size distibutios wee cotolled, e simil, but bette th the bse cse site i which the fluxes wee ot sized. Site popeties theefoe beefit fom gi size distibutio cotol of the w site mixtue. Refeeces 1. BISWAS, A.K. Piciples of Blst Fuce Iomkig, Uivesity of Queesld, Bisbe, Austli, p VENKATARAMANA, R., GUPTA, S.S., d KAPUR, P.C. A combied model fo gule size distibutio d cold bed pemebility i the wet stge of io oe siteig pocess. It. J. Mie. Pocess., vol. 57, 1999, pp RANKIN, W.J. d ROLLER, P.W. The mesuemet of void fctio i beds of gulted io oe site feed. Ts. ISIJ, vol. 25, 1985, pp The Joul of The Southe Afic Istitute of Miig d Metllugy VOLUME 108 REFEREED PAPER MAY

8 SAIMM_57-64:Templte Joul 6/9/08 11:55 AM Pge 300 Cotol of the gi size distibutio 4. TEO, C.S., MIKKA, R.A., d LOO, C.E. Positioig coke pticles i io oe siteig, ISIJ It., vol. 32, o. 10, 1992, pp LITSTER, J.D. d WATERS, A.D. Kietics of io oe site feed gultio, Powde Techology, vol. 62, 1990, pp BERGSTRAND, R., KHOSA, J., WATERS, A., d GARDEN, J. The effect of M Mmb oe dditio o the gultio chcteistics of pisolite bsed d hemtite bsed site bleds, ISIJ It., vol. 45, o. 4, 2005, pp KHOSA, J. d MANUEL, J. Pedictig gultig behviou of io oes bsed o size distibutio d compositio, ISIJ It., vol. 47, o. 7, 2007, pp FORMOSO, A., MORO, A., PELLO, G.F., MENENDEZ, J.L., MUNIZ, M., d CORES, A. Ifluece of tue d pticle size distibutio o gultio of io oe mixtues used i site std, Iomkig d Steelmkig, vol. 30, o. 6, 2003, pp LITSTER, J.D. d WATERS, A.G. Ifluece of the mteil popeties of io oe site feed o gultio effectiveess. Powde Techology, vol. 55, 1988, pp LOO, C.E. d PENNY, G.C. Gultio behviou of io oe bleds cotiig cose, poous oe, Tsctios of the Istitutio of Miig d Metllugy, Sectio C (UK), vol. 107, Sept. Dec. 1998, pp. C111 C ELLIS, B.G., LOO, C.E., d WITCHARD, D. Effect of oe popeties o site bed pemebility d stegth, Iomkig & Steelmkig, vol. 34, o. 2, 2007, pp XU, J.Q., ZOU, R.P., d YU, A.B. Qutifictio of the mechisms goveig the pckig of io oe fies, Powde Techology, vol. 169, 2006, pp MAEDA, T., FUKUMOTO, C., MATSUMURA, T., NISHIOKA, K., d SHIMIZU, M. Effect of ddig moistue d wettbility o gultio of io oe, ISIJ It., vol. 45, o. 4, 2005, pp MAY 2008 VOLUME 108 REFEREED PAPER 14. LITSTER, J.D. d WATERS, A.D. Ifluece of the mteil popeties of io oe site feed o gultio effectiveess, Powde Techology, vol. 55, 1988, pp BHAGAT, R.P., CHATTORAJ, U.S., GOSWAMI, M.C., SINGH, D.P., d SIL, S.K. Effect of size pmetes of mix igediets o the poosity d eductio chcteistics of site, Steel Resech It., vol. 78, o. 6, 2007, pp HOSOTANI, Y., KONNO, N., YAMAGUCHI, K., ORIMOTO, T., d INAZUMI, T. Reductio popeties of site with fie dispesed poes t high tempetues of 1273K d bove, ISIJ It., vol. 36, o. 12, 1996, pp KASAI, E., RANKIN, W.J., d GANNON, J.F. The effect of w mixtue popeties o bed pemebility duig siteig, ISIJ It., vol. 29, o. 1, 1989, pp OTOMO, T., TAKASAKI, Y., d KAWAGUCHI, T. Popeties of coe oe i qusipticle equied fo lge mouts usge of limoitic oes i io oe siteig pocess, ISIJ It., vol. 45, o. 4, 2005, pp KAMIJO, C., MATSUMURA, M., d KAWAGUCHI, T. Siteig behviou of w mteil bed plcig lge pticles, ISIJ It., vol. 45, o. 4, 2005, pp OYAMA, N., SATO, H., TAKEDA, K., ARIYAMA, T., MASUMOTO, S., JINNO, T., d FUJII, N. Developmet of cotig gultio pocess t commecil siteig plt fo impovig poductivity d educibility, ISIJ It., vol. 45, o. 6, 2005, pp VENKATARAMANA, R., KAPUR, P.C., d GUPTA, S.S. Modellig of gultio by twostge uto-lyeig mechism i cotiuous idustil dums, Chem. Eg. Sciece, vol. 57, 2002, pp HSIEH, L.-H. Effect of w mteil compositio o the siteig popeties. ISIJ It., vol. 45, o. 4, 2005, pp The Joul of The Southe Afic Istitute of Miig d Metllugy