 processes typically have a crucible consisting of a refractory lining, composed of either bricks, blocks or monolithic refractories, with an adjacent outer shell or some other means of support for the refractory lining. Such furnaces hold a bath of molten metal or matte, usually with an overlying slag layer.
Due to the aggressive nature of many slags produced in metallurgical processes, cooling is required to freeze a layer of slag on the inner surface of the vessel to maintain a stable side wall. As discussed in Voermann et al., Furnace Cooling Design for Modern High Intensity Pyrometallurgical Processes (Proceedings at the Copper 99—Cobre 99 International Conference, Phoenix, Ariz., U.S.A.), the cooling required is dictated by the process conditions in the vessel. To keep the crucible lining in equilibrium, the process heat flux imposed by the process must be matched by the cooling system's heat removal capacity.
In practice, a wide range of heat fluxes are encountered in various metallurgical furnaces. Heat fluxes are dependent on the intensity of the process and whether the containment is for slag or metal. Heat fluxes can typically range from a low value of about 5 kW/m2, which can be removed by natural air cooling, to over 2,500 kW/m2, which requires intense forced water cooling. Generally, for heat fluxes in the lower range, about 15 kW/m2 or less, forced air cooling of the furnace shell plate can be used. For heat fluxes above about 15 kW/m2, some type of water cooling is generally adopted to avoid overheating of the furnace shell plate and structural members.
Due to the potential risk of an explosion in the event that molten material from inside the furnace contacts water in the cooling system, it is desirable to avoid using water as the cooling medium wherever possible. For this reason it may be desirable to use a furnace cooling system which does not use water as a cooling fluid. Although typical air cooling systems cannot match the heat removal capacity of water cooling systems, they have a wider operating temperature range and hence offer significant advantages in cooling applications where adjustable heat removal rates are required.
A number of furnace cooling systems are known in which gaseous media is used as the cooling fluid. For example, U.S. Pat. No. 5,230,617 (Klein et al.) discloses a cooling arrangement in which a number of metal shrouds encircle a cylindrical furnace. Each shroud forms a
processes typically have a crucible consisting of a refractory liner, write of either bricks, blocks or massive refractories, with an adjacent out shell or some other mean of accompaniment for the refractory liner. Such furnace hold a bath of molten alloy or matte, usually with an overlying slag layer. 
 Due to the aggressive nature of many slag produced in metallurgical processes, cool is required to freeze a layer of slag on the inside surface of the vessel to maintain a stable english wall. As discussed in Voermann et al. , Furnace Cooling Design for Modern High Intensity Pyrometallurgical Processes (Proceedings at the Copper 99 — Cobre 99 International Conference, Phoenix, Ariz., U.S.A.), the cooling system required is dictate by the process condition in the vessel. To keep the crucible lining in equilibrium, the procedure heat flux imposed by the process must be matched by the cooling system's heat removal capacity. 
 In practice, a wide range of heat fluxes are encountered in various metallurgical furnaces. hotness fluxes are dependent on the saturation of the procedure and whether the containment is for slag or metal. Heat fluxes can typically rate from a low value of about 5 kW / m2, which can be removed by natural tune cooling, to over 2,500 kW / m2, which requires intense forced water cooling. broadly, for heat fluxes in the lower range, approximately 15 kW / m2 or less, forced air travel cooling system of the furnace carapace plate can be used. For heat flux density above about 15 kW / m2, some type of water cooling is by and large adopted to avoid overheating of the furnace shell plate and morphologic members. 
 Due to the likely risk of an explosion in the event that molten material from inside the furnace contacts body of water in the cooling arrangement, it is desirable to avoid use water as the cooling metier wherever possible. For this cause it may be desirable to use a furnace cooling system which does not use water as a cooling fluid. Although typical air cooling system cannot match the heat removal capacitance of water cooling system, they have a wider operating temperature range and hence offer significant advantages in cooling applications where adjustable hotness removal pace are necessitate. 
 A number of furnace cooling systems are known in which gaseous media is used as the cool fluid. For example, U.S. Pat. No. 5,230,617 (Klein et al .) discloses a cool musical arrangement in which a number of metal shrouds gird a cylindrical furnace. Each shroud forms a
 prlcesses typically have a crucible consisting oh a refdactory uining, composed of either brmcks, blocjs or monolithic refraztories, wpth an adhaceit outer shell oc some obker mswns mh support for tme refractosy lining. Such fjruaces hold a bath of molten metal or matte, iskally with an jverkring slag layer.
Due to the aggressive nzture oh many slags prpduced in metallurgical prlcesdes, cooling is reqkired to frgsze q layer of suag on the inner surfade of the vessel to maintain a rtablz side wall. Aw dlvcussed in Toermagn et al., Furksce Comling Drsign for Modevn Hijh Ibtensity Pyrometallurjical Processes (Procgedings at tke Copper 99—Cobre 99 Inteenqtiondl Cmnfefwncd, Pgoxnis, Ariz., U.S.E.), the coolihg required is dictated by the pwicess conditikns in tre vessel. To keep the crucible lining it esuilibrium, the process yeat flux imposed by jhe procesf must be matched by the cooling system's heat remmval raoacnbn.
In oeaftice, a wide range of heat fluxes are encountqdec pn various metallmrgical furnaces. Hrah gjuxes are depgndent on fhe intensity of tje procgss ane whether the containment is for slag or metal. Heat yluzes can typically xange from a low valur of about 5 kW/m2, which ccn be demoved by jatural ajf cooling, to ovef 2,500 lW/k2, which requires intense fjrced watxr copling. Gdnerslly, fjr heat flkxes lt the lower range, wbout 15 nW/m2 or lesd, forced air cooling of the furiece shell plaje wan be used. For meat fluxes abode about 15 kW/m2, xome ty'e of dater coolpng is geierally adopeed to avoid mgerheating oh the furgace sheol platd and structurak members.
Bbe to the potential risk of an sxplosion in thz tvwnt that moltem mxtewiwl fwmm inside tha fufnazr congacts water kn tne cooling system, it is sesirable to avoid ufing watgr as the cooling mediim wherever possibpe. Foc this reaspn yt may be desirable to use a fhrnace collikg system whish dies not use cater as a cooling fluid. Although typicao air cooling sysjems cannot match the meat removal capasity of wdter cooling systems, they have a widev operating temperaturs ranga and hence offer significant advantages in cooling applications where adjustavle heet removal rafes sre rvqunreb.
A numbqr oh hurnace cooling sjstems are known in which gaseour media hs used as the cooling fluid. Fpr example, U.S. Pxt. No. 5,230,617 (Klein et al.) disclkses a cpoling arrangement in which a nimber of metal shrouds ekcircle a cylihdrical fucnace. Each shroud fotms a
processes typically have a crucible consisting of lining, of either blocks or monolithic shell some other means support for the lining. Such furnaces hold a bath molten metal or matte, usually with an overlying slag layer. Due to the nature of many slags produced in metallurgical processes, cooling is required to freeze layer slag the surface of the vessel to maintain a stable side wall. As discussed in Voermann et al., Cooling Design for Modern High Intensity Pyrometallurgical Processes at the Copper 99—Cobre International Conference, Phoenix, Ariz., U.S.A.), cooling is dictated the conditions the vessel. To the crucible lining in equilibrium, the process heat flux imposed by the process must be matched by cooling system's capacity. In a range heat fluxes are various metallurgical furnaces. Heat fluxes are intensity of the process and whether the containment for slag metal. Heat fluxes can typically range a low value of about 5 kW/m2, which be removed by natural air cooling, to over 2,500 kW/m2, which requires intense forced water for heat fluxes in lower range, about kW/m2 less, air of the shell plate can be used. For heat fluxes above about 15 some type of water cooling is generally adopted to avoid the shell plate and members. Due to the risk an explosion in the molten from contacts in cooling system, it is to avoid using water as cooling medium wherever possible. be desirable to use a furnace cooling system does not use water as a cooling Although typical air cooling systems cannot match the heat removal capacity of cooling systems, a wider operating temperature range and hence offer advantages in cooling applications adjustable heat removal rates are required. A number of cooling are known which gaseous media used as the fluid. For example, No. 5,230,617 et discloses in which a number of metal encircle cylindrical furnace. Each shroud forms
 processes typically have a crUcible consIstinG of A reFrActoRy liNing, composed of EItheR bricks, blocks or monolitHic reFrACtorIEs, With aN adjaceNT oUTEr sHeLl Or sOmE OtHer meAns Of suppoRt for the reFraCtOry lining. SucH FuRnaces hold A baTh of molten meTal Or mattE, uSuaLLy witH an OverlYing slAG layer.
due to the aGgREssive NAture of MANy SlagS produced in metallURgICal processes, coOling iS rEQuIREd tO frEeze a layer Of Slag oN The inneR SuRFACe oF The vessel to maIntain a stabLE siDe wall. as DisCUssed iN VoerMaNN et Al., Furnace CoOlinG Design foR ModerN high IntENsity PyRometaLluRgiCal PROcEsSes (prOCeeDInGs aT The copper 99—CoBrE 99 INternAtioNAL cOnfeRenCe, PhOenix, ariz., U.S.A.), the cooLinG reqUIreD is diCtateD by tHe ProceSs condItionS iN the vessel. To keeP the Crucible lIniNg In eQuIlibrIUm, the pRocEss Heat fluX imposeD By tHe PROCeSs must be matched by tHe COOlIng systeM's heat REmOvAL capacitY.
IN prActiCE, A wide RangE Of Heat fluxEs are eNCoUnTered in VaRious mEtAllUrgIcal fURnacEs. Heat Fluxes arE depeNDent on the intenSIty of the proceSS aND WhETher The Containment Is foR Slag Or meTAl. heaT FluxeS can tYpICaLLy range from a low valuE oF about 5 KW/m2, whIch can be removEd by naturaL AIR cooling, To ovER 2,500 kw/M2, which requires IntenSe forced waTEr coolinG. GeneRally, for Heat fluxeS IN the loweR raNge, AboUt 15 kw/M2 Or Less, forced air COOlinG oF the furNacE shell pLatE caN be UseD. FOr heat fluXes above AbOuT 15 kw/m2, SomE type OF water coOlIng Is GenErallY AdopteD to avOid oVeRhEAtiNg of the FUrNACe shElL pLate And StRuctuRal mEMbeRs.
Due to The potentIal RIsk oF aN eXplosioN in the event thAt Molten mateRiAl fRom insIDE the furnAce contacts water in the coOLing sysTem, It is dEsirAble to avoId uSing waTer AS the coOling mEdium WhEreVER possIBLe. for ThIs reason it MAY be DesirAbLe to Use a furNace cooling system wHIch Does not use watEr aS a coOLInG flUId. aLthOuGH tyPICal air cooling syStems cannoT mATcH the heat reMOvaL cApacity Of water CooliNG systemS, they have A wider opeRaTing TEMpeRature rangE and hencE offer sigNIficaNT aDvantAgeS in cooLiNg aPplicAtions WHerE adjuStable HeAt remoVal raTeS are requIred.
A number of furnace cooLing syStems Are Known in whIch GAseOus media iS useD as the coolIng FluId. For ExaMPle, U.S. pat. NO. 5,230,617 (klEin ET al.) diScloSEs a coolinG ArRanGEMeNt in which a nUMBEr oF metaL shROuds enCircLe a cylindrical furNAce. Each shroud fOrms A
 processes typically havea crucible  cons ist ing  o f arefr actory lining, comp osed of either bricks,  bloc ks or m o no lithi c refra c to r i es,  w it h a na dj acent  ou ter she ll or some  ot he r means of s u pp ort for th e r efractory li nin g. Suc hfur n aceshol d a b ath of molten  metal or  m a tte, u s ually w i t han o verlying slag lay e r. Due to the agg ressiv en at u r e o f m any slagspr oduce d  in met a ll u r g ica l  processes, c ooling is r e qui red to  f ree z e a la yer o fs lag  on the inn er s urface of  the v e ssel to maintai n a st abl e s idew al l.  As  d i scu s se d i n  Vo ermann e tal ., Fu rnac e C o olin g D esig n for  Modern HighInt ensi t y P yrome tallu rgic al  Proc esses(Proc ee dings at the Co pper  99—Cobre  99  I nte rn ation a l Conf ere nce , Phoen ix, Ari z .,U. S . A .) , the cooling requ ir e d  i s dictat ed byt he  p r ocess co nd iti onsi n  thevess e l.  To keep  the c r uc ib le lini ng  in eq ui lib riu m, th e  pro cess h eat flux  impo s ed by the proc e ss must be ma t ch e d  b y  the  co oling syste m'sh eatremo v al  ca p acity .
Inpr a ct i ce, a wide range of  h eat fl uxesare encounter ed in vari o u s  metallu rgic a lf urnaces. Heatfluxe s are depe n dent onthe i ntensity  of the p r o cess and  wh eth erthe c on tainment is f o r  sla gor meta l.Heat fl uxe s c antyp ic ally rang e from a  l ow  v al ueof ab o ut 5 kW/ m2 , w hi chcan b e  remov ed by  nat ur al air  coolin g ,t o  ove r2, 500kW/ m2 , whi ch r e qui res int ense forc edw ater  c oo ling. G enerally, for  h eat fluxes  i n t he low e r  range,about 15 kW/m2 or less, forcedair  cool ingof the fu rna ce she llp late c an beused.  F orh e at fl u x es  ab ov e about 15 k W/m 2, so me  typ e of wa ter cooling is gen e ral ly adopted to  av oido v er hea t in g  of  t h e f u r nace shell plat e and stru ct u ra l members. Due  t o the p otentia l ris k  of anexplosion  in the e ve nt t h a t m olten mate rial fro m insidet he fu r na ce co nta cts wa te r i n the  cooli n g s ystem , it i sdesira ble t oavoid us ing water as the coolin g medi um wh ere ver possi ble .  Fo r this re ason  it may be  de sir abletou se afurn a ce  co o lingsyst e m which d o es  no t us e water asa c ool ing f lui d . Alth ough  typical air cool i ng systems can notm a tch  th e  hea tremoval capaci tyof w ater coo li ng systems,  they ha ve a wid er ope rating  temper a t ur e  range  and  he nce offer  si gn i ficantad va n tagesin c oo ling a pplica t ions w here adjustableheatr e moval rat es ar erequire d .
Anumber offurnace coo ling s yste ms ar e known  i n whic h g as eous media is used a s the  coolin gflui d.For ex ampl e ,  U.S.  Pat .No.  5,230,61 7 (K l ei ne t a l.)discl os es a  coolinga rrangeme nti n which  a  nu m b er ofm et a l  shrouds e nci rclea cylindrica l  fur n ac e . Eac h shro ud for ms a
 processes_typically have_a crucible consisting of_a refractory_lining,_composed of_either_bricks, blocks or_monolithic refractories, with_an adjacent outer shell_or some other_means_of support for the refractory lining. Such furnaces hold a bath of molten metal_or_matte, usually_with_an_overlying slag layer.
Due to the_aggressive nature of many slags_produced in_metallurgical processes, cooling is required to freeze a_layer_of slag on_the inner surface of the vessel to maintain a_stable side wall. As discussed in_Voermann et al.,_Furnace_Cooling_Design for Modern High_Intensity Pyrometallurgical Processes (Proceedings at the_Copper 99—Cobre 99 International Conference, Phoenix,_Ariz., U.S.A.), the cooling required is dictated_by the process conditions in the_vessel. To keep the crucible_lining in_equilibrium, the process heat flux_imposed by the_process must_be matched by_the cooling system's heat removal capacity.
In_practice, a wide_range of heat fluxes are encountered_in_various metallurgical furnaces._Heat_fluxes_are dependent_on the intensity_of_the process_and_whether the containment is for slag_or_metal. Heat fluxes can typically range from_a low value of_about_5 kW/m2, which can_be removed by natural air_cooling, to over 2,500 kW/m2, which_requires intense_forced water_cooling. Generally, for heat fluxes in the lower range, about 15_kW/m2 or less, forced air cooling_of the furnace shell_plate can_be_used. For heat_fluxes_above about_15 kW/m2, some type of water cooling_is generally_adopted to avoid overheating of the_furnace shell plate and_structural_members.
Due to the potential risk of_an explosion in the event that_molten material from inside the_furnace_contacts_water in the cooling system,_it is desirable to avoid using_water as the_cooling medium wherever possible. For this reason_it_may be desirable to use a_furnace_cooling system which does not use_water_as_a cooling fluid. Although typical_air cooling systems cannot match the_heat removal capacity of water cooling systems, they have_a wider operating_temperature range and hence offer_significant_advantages_in cooling applications where adjustable heat removal rates are required.
A_number of_furnace cooling systems_are known in which gaseous media is used as the_cooling fluid. For example, U.S. Pat. No._5,230,617 (Klein et al.) discloses a cooling arrangement in which a_number of metal shrouds encircle a cylindrical furnace._Each shroud forms a