Note: Descriptions are shown in the official language in which they were submitted.
CA 02467310 2004-05-14 --
COMBINfED IRONMAKING AND STEEd:~MAKING PLANT
TECHNICAL FTELD
The present invention relates to a combined
i.ronmaking and steelmaking plant for produca.ng molten steel
from an iron-bear~.ng metalliferous fee=_d material such as
ores, partly reduced ores and iroxs.-contayr~ing waste
streams.
The present inventyon relates particularly,
although by no ~mearas exclus~.veZy, to a combined iror~aking
and steelmaking plant for producing :.molten steed. by a
process that includes producing molt~an sron in as
ironmaking vess~al by a direct smeltivag process, more
particularly a molten bath-based direct smelt~.ng process,
and thereafter ,~xoduczng steel from ~.tlae molten iron in a
steelmak3ng vessel, by a basic oxygen j~rocess.
The term '°dixeat smelting p~-ocessK is understood
hexein tv mean a thermal process for j?roducing molten zron
directly from an ~.ron-hearing metall:L:Eerous feed material
such as ores, partly reduced ores anri iron-containing waste
streams, whereixn chemical reactions 3: educe the
metall.iferous feed material to molten iron.
The Hlsmelt process is a molten bath-based direct
saeelting process ~or producing xnoltexd a.ron. The Hlsmelt
process is described, by way of example, an International
Application FCT/'AtT96/OC1197 (P10 96/31~:~'7) in the name of the
applicant. The H~Csmelt procega is ar,~ alternative process
to the eonvex~.tional blast furnace-based direct smelting
process for prpducing molten ~,ron.
The xTsmelt process hag been tested successfully
at development plant level. and a rela.ited company of the
-- applicaait is now constxuating a aoa~ercial plant at
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KWinana, western Australia.
The I~Ismelt process, and other molten bath-based
direct smelting processes that have been proposed a,n the
literature, enable large quant~,ties o:E molten iron to be
produced by direct smelting in compact vessels.
The basic oxygen psvcess is a commonly used
process for making steel. The proee-s~s enables large
quantities of molten steel to be prodaced from molten iron
in compact vessels.
Tha present invention is based on the realisation
that with careful design the above-derscribed compact direct
smelting and str~elmakirig vessels mak~s a.t poss~.ble to
produce molten iron and thereafter s~t~eel. using a quite
daf~erent plant layout to that o~ tra.ditiozial integrated
steelworks.
In traditional integrated >:si:.eelwosks, ironmaking
and steelmaking are essential3y separ;~,te operations and
ironmaking plants and steelmaking plants are spaced apart
by re~.atively 1<<rge distances with3.r~, the boundaries of
integrated stee~.wor3cs. Molter~ iran ~.as transferred from
~.ronmaking to steelmakzng plants in purpose-built torpedo
cars that run or.~ rail tracks between ~tlE~e plants . When the
torpedo cars reach steelmaking plantsr the molten iron is
discharged into ladles, and the 7.adlerg transport molten
iron as required wa.thia the steelmaking plants. Depending
on the circuansta.nees, molten iron may be treated by being
desulphurised ax~.d/or dephosphor~.sed 3.~a the ladles before
the ladles are moved to steelmaking vnasse3.s and the treated
iron is discharged from the ladles ixs.ito the vessels and
processed tv produce steel.
Tl;e above-der3cribed multiple handling of each
batch of molten iron and the long transfer distances
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between iranmaking anal steelmaking ~~lants are d3.aadvazitage$
of trad3t~.or~.al integrated steelworkQ.. The step of
transferring batches of molten iron from ore receptacle to
another introduces time delays and inevitablg results in
temperature losses in the molten metal. The temperature
losses are an 3.mportant eor~sideratian ga.ven that '~ta.ere is a
relatively small temperature window between the tapping
temperature for molten iron and the m:iraimu-en feed
temperature for steelmaking vessels.
~. 0
In adda.tion, the u$e of torpedo cars represents a
substantial investment ~.u texzns of ta~r~ cars themselves, the
rail networks for the cars, the locoz~u~ti.ves to move the
cars, the plant and equipment, that i;a required to clean,
repair, and re-Nine the cars, and the plant and equzpmer~,t
that is required to preheat the cars pr3.or to receivarxg a
batch of mo~.ten iron.
The plant layo~.r.t of the combined ironmaking and
steelmaking plant of the present inve~at~.on avoids the
above-described disadvantages of trad:i.ta.onal ix~.tegrated
steelworks.
The plant layout of the present invention is
suitable particularly, although not e~~eclusively, for a
green~ield site.
n=seLOSVRS of TAE zrm~rrzorr
According to the present invention there is
provided a combined iros~making and steelmaking plant
including:
(a) a dyrect smelting irorux~aking plarJa for
producing molten iron from an a.roa-blaring metalliferous
feed materiaz such as ores, partly re,ziuced ores and iron-
containing waste streams, th~ ironmak~:ng plant including an
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ironmaking vessel;
tb) a steelmaking plant fc~r receiving molten
iron and producing molten steel from xr~cslteas iron. the
steelmaking plant including a steelmakang ~ressely
(c) ~~t leant one receptae°!a fos receiving and
holding molten iron from the ironmaking vessel and for
discharging xaaljten iron directly a.ato the steelmaking
vessel; and,
(d) a transfer means fox f:ransferring the
receptacle between (a.) an operative Jaa~sitign at the
irarmnaksng vess<.1 at which the raeep~a.cle cars, receive
molten iron froze the ironmaking vessel and (ii) an
operative positvon at the.steelmakin~ vessel at which the
receptacle can discharge molten iron d~ixectly into the
steelmakiag vessel an d thereby links t,ogeth~ar the
ironmaking vessel and the stealmaking vessel, the transfer
means including a transfer crane far supporting the
receptacle and a transfer crane ruxzway that def~.nes a path
of movement for the crane.
With the above-descr~.bed combir~.ed plant, the
ironxnaking vease~, can transfer molten iron directly into
the receptacle vahen the receptacle is positioned at the
operata.ve position at the ironmakang vessel.
In add~.tion, with the abova-described combined
plant, the ironmaking vessel, the steslmaking vessel and
the transfer means are positioned in relat~.on to each other
so that a receptacle eonta3.nsng moltan iroxi can be carried
by the transfer crane from the operative possta,ormat the
ironmaking vessel along the transfer,crane rmw~y to the
36 operative position at the steelniakinc~ vessel. and molten
iron can be discharged da.rectly from the receptacle a,nto
the steelmakixxg vessel.
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The avbove-described combined plant is centred on
the transfer means and the relat~.ve poss.tioas of the
transfer means, the ironmaking vessHl, and the steelmaking
vessel that links together the operative positions of the
5 receptacle at t:he ironmaking vessel a~ad the steelmaking
vessel and makes it poBSible to use one receptacle on~.y for
transferring a given batch of a~oltermiron the whole
distance from the irorunaking vessel tea the steelmaking
vessel by means of the transfer means.
Preferably the ironmaking vessel is adapted to
discharge molten iron continuously fr~oact, the vessel.
With such an arrangement, preferably the combined
~5 plant secludes at least two xeeeptacl~as arid the ironmaking
plant ialcludes a means for selectivel;Y supplying molten
iron discharged continuously from the ironmakiag vessel
into one ox~ other of the receptacles .at the operative
position at the ironmakira.g plant.
Preferably the operative position at the
steelmaking v-es;ael is an elevated position in a~~lation to
the operative position at the ironmaJcing vessel..
Prefea~ably they combined pl~.gt further includes a
molten iron tre;~.tment plant for trea~t~.,ng molten iron
positioned in relation to the trar~sf~:r crane runway so that
a receptacle containixag molten iron ~zan be transferred from
the operative position at the iroazmaleing vessel to an
operative positaLon at the molten iron treatment plant;
thereafter the molten iron earl be treated at the molten.
iron treatmea,t ~>larxt, and the receptacle means can then be
carried by the transfer crane along 9::he transfer crane
a:unway to the operative position at t;he steelma,~sing vessel
and the treated molten iron can be d~.seharged directly from
the receptacle into the steelmaking ~>~essel.
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Preferably the iranmaking veessel and the molten.
iron treat_mex~,t ,plant are on opposite Faides of the transfer
runway.
Preferabllr the operative p~~sita~ons at the
s.ronmaki.ng vessel and the molten iron treatment plant are
directly across from one another.
Prefea:ably the transfer mear.:s includes a transfer
car or other suitable moltexi iron tra.nsfex means for
supporting and transferrir~g the receptacle xneang corataining
molten iron frv=n the operative pos3.t:ion at the ironmaking
vessel to the operative posit~.on at =he molten iron
treatment plant" This is a conveniemt~ arrangement for
tr~nsferrs.ng molten iron from the irorsmaking vessel to the
molten iron treatment unit.
Preferably the transfer measxs ineludes a rail-
mounted transfer car for supporting Gtnd transferring the
ree:eptacle means coxataining molten iron from the operative
position at the ironrnaking vessel to t:he operative position
at the molten iron treatment plant.
preferably the transfer caw and the transfer
crane are adapted to ogerate indepe~nclc~ntly of each other.
Preferably the molten iron t:reataanent plant xs a
desulphurisation plant that is adapted to desulphuris~e
molten iron. in the receptacle means in situ oxr the molten
iron transfer means,
Preferably the combined planW further includes a
molten iron solidification plant for casting molten iron
into pigs or other moulds or for quenching molten iron into
granules or for otherwise Forming so3.xd iron positioned an
relation to trhe transfer crane runway so that a receptacle
contaixllng molten irora can be carried by the transfer arena
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along the transfer crane runway to an operative position at
the solidification plant e.n.d molten ix-on cars be discharged
from the receptacle ~.nto the Bolidzfic:atio~. plant.
Preferably the operative p.~sitic~r~, at the
ateelxnakiag vessel and the operative posit~.oa at the
soaidificatioxs plarxt are at opposite ends of the transfer
crane runway.
3. o Preferably the combir~.ed plawt further includes a
receptacle heat:iag stand positioned :Lxt relation to the
transfer craae runway so that as emp~=y receptacle can be
heated at the the receptacle heatixxg atend and then~after
carried by the 1_ransfer crazse along t:he trraxsafer crane
runway to the operative position at t=he ironma3sing vessel
to be filled with molten. iron.
preferably the transfer cra~rne rux~way is straight.
Preferably the direct smelt3.ng iroruna.king plant
is adapted to px-vduce molten iron by a molten bath-based
direct smelting process.
Preferably molten riath-basest direct smeltixs.g
process is the ~3tlsxnelt process.
Preferably the receptacle is a ladle.
Preferably the transfer cra~~e and the ladle are
adapted to allow for tilting m ladle containing molten iron.
towards the steelmaking vessel so that: molten iron cars be
discharged from the ladle whsle supported by the transfer
crane.
Preferably the steelmaking v~sssel as adaptred to
tilt towards a ladle contaia~.ixag molteri iroxz when the ladle
is at the operative positiosx of the steeimaltin.g vessel to
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facilitate discharging of molten iron into the steelmaking
vessel.
According to the present inveastion there is also
provided a method caf making steel ir. the combined
irenmaka.ng and steelmaacing plant described above which
includes making molten 3,ron a.n the r~,y;~ect smelting
ironmaking plant, discharging molten iron from the
iroamaking vessel into the receptacle at the operative
posit3.on of the iro~naking plant, tramaferring the
receptacle containing the molten iron to the steelmaking
plant using the transfer means. discharging molten irons
from the receptacle into the ateelma.k~.ag vessel, and making
steel from the ~onalten iron in the steelmaking plant.
Preferably the method fustizer includes
transferring the receptacle contafns;~ng the molten ~.ron from
the irox~aking plant to the molten iron treatment plant
using the transfer means, treat~.ng t;~r~ molten. iron at the
molten iron trer~tmer~t plant, and thermafter transferring
the receptacle ~~on'ta~.ning tha treated molten iron to the
steelmak~.ag plaint .
pxefersbly the method inelmdss aoatinuously
discharging molten, iron from the ironmaking~ vessel iz~.to one
of two receptacles at operative posir:9.ons of the ironmaking
plaxxt.
BRIEF DESCRIPTION OF THE DRAHTINGS
The present a.nvention is described in more detail
hereinafter with reference to the aaecssnpanyzng drav~risigs, of
Which:
Figure 1 ~.s a layout of one embodiment of a
combined 3.ronmak,ing and steelmaking plant in accordance
with the present invention) and
CA 02467310 2004-05-14
F3.gur~a 2 is a detailed view of one past of the
layout shown in Figure 1.
DBTAIhEb DESCRIPTION OF THE PRRFERRE;D EMBODIMENT
The combined ironmakin.g and steelmaksag plant
shown in the figures includess
(a) asr. ironmaking plant enolosed v~tith.ia the
stashed line marked CI~T on the figure for
producing molten iron i,n accordance with the
f'IIsmelt process in a t:i,xed, compact direct
scmelting vessel 11;
(b) ladles L5 or other suitable receptacles for
rece~.ving, holding, arldl discharging molten
iron produced by the a~x~onmaking plant,
(e) a, steelmsking plant tY.~a~~t includes two basic
oxygen furnaces (BOF) 7 for producing steel
from the molten irora in accordance wa.th the
basic oxygen process,
(d) a molten iron treatment: plant 41 ixz the form
of a desulphurisat3on plant for
desulphurising molten iron xa a ladle 3.5;
and
(e) a transfer means for tranferring ladles 15
containing molten zroa from the direct
smelting vessel 11 to t:he desulphurisation
plant 41 and therea~te.r transferrir~.g ladles
containing desulphurised molten iron to the
BOFs 7 and for tipping the ladles to pour
anolten iroxi from the ladles into the BOFs 7
apt the steelmakiag ~ani~t:.
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The combined plant also includes a molten
solxdifi.cation plant in the form of an. iron casting plant
43 for canting molten iron inter pigs.
The combined plant also includes a pair of ladle
heating stands .~-al for pre-heating empty 7.adles prior to
moving the ladya=s tv the iroruna7~irtg hl,a~nt ~zU to be filled
with molten aron.
7.0 The ts-ansfer means includet~ (a) rail-mounted
transfer cars 55 ( shown Jmore clearl~r in Figure 2 than in
Figure 1) that support and transfer _Lwr~les 15 filled with
molten a.ran from the direct smelting weasel 11 to the
desulphur3.sation plant 41 and empty ~a~dles 15 to the vessel
11, (b) an overtlaad transfer crane 3!i for lifts.ag and
carrying the ladles ~.5. and (c) a rurxHray 9 that defines a
path of movement for the crane 35.
The rail-mounted transfer cars 55 fac~.litate
movement of ladles 15 fi.~.led with molten iron across the
width of the runway 9 from the direct: smelting vessel I1 to
the desulphurisation plant 41..
The crane 35 and the runway 9 facilitate
movement: of the ladles 15 alox~g the Length of the runway 9
and across the width of the runway 9.
Tx~, addit;ion, the transfer cars 55, the crasse 35
and the runway 9 facilitate movement of pre-heated empty
ladles ~.5 from the ladle heating stands 51 to the direct
smelting vessel 11.
=t is evident from the above and the figures that
the paths of movement of the transfer cars 55 across the
runway 9 and the crane 35 along the rmnway 9 irsterseet.
The transfer cars 55 and the craze 35 can move
independently of each other and, accordingly, in order to
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avoid interference, the crane 35 i.s adapted to lift ladles
1S well clear e~f the transfer cars ~5.
The steelmaking pleat is characte~xised fn that
the direct smelting vessel 11, the BOhs 7, the
desulphurisatiox~, plant 41, the pig casting plant 43, and
the ladle heating stands 5~: are positioned in relation to
the transfer mea:as so that the ladies 15 can be moved by
the transfer means to operative posit_i.ons at the vessel. 11,
the BOl~s 7, the plants 43., 43, and the ladle heating stands
51.
Specifically, the operative posita.on for the
ladles l5 at thw direct smelting vessel 11 is the pos3.tion
I5 of the ladles 1;'s ixa, the figures, se ~~os~.tio~as at which a
pair of the ladies 15 can receive molten iron darect7.y from
the vessel 11 via a hat metal lauride~: 13 and a filter
runner assembly 61 (see Figure 2).
The ogarative positiozi for the la.dlea 15 at the
BOFs 7 is elewat:ed positions air which the ladles 15 can be
tilted to pour molten iron ire, the ladles 15 directly snto
the BOFs 7.
The operative position for the ladles 1S at the
desulphurisatioa plant 42 is a position at which molten
m~eta7. can be desulphurised in the ladles 15.
The operative positions for the ladles 15 at the
d~.rect smelting vessel 11 and the desv,Iphurisation plant 41
are at the same horizontal level and a.=e dasectly across
from one another so that there is a straight line transfer
of the 7.adles 15 via the trax~.sfer cars 55 from the direct
smelting vessel ~.1 tc the desulphurisatioa una.tw4l.
The opearative position fox the ladles la at the
pig casting plarat 43 is au elevated p~asitiox~ at which the
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ladles 15 can, be tslted to pour ~oitea, iron is the ladles
1S directly into the parallel pig casting lir~ea.
The above-described locations of the direct
smelting vegsel 11, the steaLa~al~ing unit, the
desulphurisatioa pleat 41, the pig casting plant 43, sad
the ladle heating stands 51 in relat3~on to the transfer
means, and more particularly in relation to the crane
runovay 9. greatly facilitates efficient transfer of molten
~,0 iron as required within the combiaec. plant. In particular,
the above-described arraugemen,t m~.r~.3~nsses the number of
ladles ~.5 and crane operations that are required to
transfer molten 3.ron from the direct. smelting vessel 11 to
the 80Fs 7.
The eoncebiaed plant also includes end tap ladles
for receiving and transferrirs,g molten iron discharged
from the darect smeZtxng vessel ~.1 via a launder 39 3n an
end tap of the vessel. The posit~,ora.s of the vessel 11 and
20 the ladles 25 a"s selected so that the: ladles 25 can be
lifted and moved by the transfer crane 35 as required to
the SOFs 7, the~ desulphurisation plarit 41, sad the pig
cast~.ng plant 43.
25 The direct smelting vessel. 11 xs a v~rater-cooled
refractory lined vessel that is adapted to contain a molten
bath of sroa a~,d :lag.
The vessel ~.1 is fitted with a gas injection
lance (not shown) for delivering a ~ovmward:Ly directed hot
air blast into an upper region of the vessel, zn use, the
lance rece3.ves an oxygen-enriched hat air blast through a
hot gas delivery duct 31 that extenaa ~roxa hot gas supply
statiox~ 23. The hot gas supply stat~.o~a 21 includes a
aeries of hot blast stoves sad an. oxygexx plant to enable an
oxygen-enriched air stream to be passed through the hot
blast stoves arid into the hot blast delivery duct 31.
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The vessel, 11 ig alsv fitted with sol~.ds
snjection lances 27 that extend downarardly and snwardly
through openingea (not shown) in the (aide walls of the
vessel ~or injecting iron ore fines, solid carbonaceous
material, and fluxes entrained in an oxygen-deficient
carrier gas into the molten bath in i~h.e vessel.
Typ3.ca~lly. the lances 2? are in 2 groups of
lances, with the: lances 2? in one gsnup receiving hot iron
IO ore fines supplied via a hot ore injection system and the
lances 27 3.n the other group rece~,ving~ coal and flux via a
carbonaceous material/flux iu~ecti.on system during a
smelting operation. The lances 2? in the 2 groups are
arranged alternaWe~.y arorazad the aireuxnferenae of the
vessel.
The hvt ore injection system includes a pre-
heat/pre-reducta.on unit 1? for heatirvg sand partially
reducing the iron ore fines axed a hot: ore transfer system
that includes a series of supply lines (not shown) and a
supply of carrier gas (~xot shown) for transportiaag the hot
ore fines in the supply lines and ixijecting the hot ore
f roes ixa.to the weasel .
The vessel 11 includes an offgas duct 32 which
transports offgas produced in the proc:eas away from the
vessel 11 to a treatment station 33 where it is cleaned and
passed through heat exchax~gers for pr~aheat3ng the materials
fed to the vessel 1~..
7Cn a s~meZting operation inn. accordance with the
Filsmelt process, ore fines, coal, and flux are 3rajected
ir~.to the molten ;bath through the lances 2? . The coal is
devolatslised and thereby produces gars in the molten bath.
Carbon partially dissolves xn the metal and partially
remains as solid carbon. The ore fines are smelted to
metal and the sm~slting reaction generates carbon morr.oxide.
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The gases transported into the metal layer axed gerxerated by
devoZatilisatioxa and smelting reactions produce significant
buoyancy uplift of xnol.ten metal, soa:id, carbon and slag.
Injection of the oxygen-containing g:~a~ via the lance post-
s combusts reaction gases in the upper part of the vessel.
Hot metal produced dur3.ag a smelting operation is
discharged continuously from the vessel 11 into oxie of two
ladles 15 at the operative position of the vessel I1. The
molten iron. is discharged into a lad:Le: 15 thxough a metal
tapping sys~esn that includes the forehearth (not shown) arad
hot metal launder 13 connected to the forehearth axed tha
titter runner assembly Cal.
The plant includes an ertd atetal tapping system
for tapping molten metal from the vessel 11 at the end of a
smeltss~,g operatj.on out of the lower p~~.rt of the vessel and
transportiry that moltezi metal away from the vessel 21.
The end metal tapping system iaeluder~ a aeetal end tap hole
(not shovm) in the vessel and the launder 39 for
transferring molten metal discharged from the vessel 11 via
the tap hole to the serzes of ladles ~5 at the position
shown in the figures.
The $Q~~s ~, the desulphurisatio~z plant 41, and
the pig castiasg plant 4~ are cotavantional unit operations.
zn use of the above-deacribad combined ironmaking
and steelrnakiag plant, molten iron is produced in the
dixect smelting iroamaking plant CIU and is discharged
continuously from the vessel 11 ~xa.to one of the ladles 15
at the operative positivxx at the weasel 11. When the ladle
15 is full, the titter runner assembT.y 61 re-directs the
continuous flow of molten irons from t;he vessel ~.1 into the
other ladle 15 at the operative position of the vessel 11.
The full ladle 15 is transferred across the runway 9 by its
associated transfer oar 55 to the de$ulphurisatioa plant 41
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is
and the mo~.ten iraa is desulphurised isa the ladle
iS.Thereatter, the ladle 15 containixag the deaulphurised
molten iron, s.s :Lifted off its associs,ted tran$fer car 55
and is transferred by the crane 35 a:lo3ng the runway 9 to
the operative position of the BOF's. Thereafter, the ladle
is tilted ax~,d the desulphura.sed molten i.roxi is
discharged into one of the 80F's. Scrap fox the HOF is
conveniently charged isito the BOF frrm the opposite side
thereof . Thereafter, steel a.s produr:ed is the 80g. After
x0 the tuiZ ladle A5 hs.s been emgied at t:he 80~, the crane 35
transfers the empty ladle 15 to the :Ladle heating stands 51
sad the ladle 15~ is pre-heated as zeqt;Wred fox subsequent
use. When required, the pre-heated empty ladle 15 is
transferred by the cras~,e 35 to the e~rty transfer car 55 at
I5 the desulphur3.aation plaut.4l. Thereafter, the ladle 15 is
tranaferxed by the transfer car 55 irlt:o the operati~re
positiora at the vessel 1x to receive a further charge of
molten iron.
Maxay modifications may be xck-~de to the embodiment
of the present invention descr3~bed grove without departing
fxom the spirit grad scope of the invesation.
