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INGLÉS TÉCNICO PARA PROFESIONALES METALÚRGICOS TECHNICAL ENGLISH FOR METALLURGISTS ASSIGNMENT / ASIGNACIÓN: 11 – Electroref!! / Electroref!#c$! LE%EL/ NI%EL: I!ter&e'#te/ I!ter&e'o NAME/ NOM(RE:))))))))))))))))))))))))))))))))))*** INSTRUCTIONS:  Translate this text into Spanish +#r# r#+, -. +#r# r#+,.  Send your translation version /!tl : Octo-er 10 t, 1 22:33 +&. INSTRUCCIONES:  Realizar la traducción del texto al español +4rr#fo +or +4rr#fo.  Enviar su versión de traducción
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  INGLÉS TÉCNICO PARA PROFESIONALES METALÚRGICOS TECHNICAL ENGLISH FOR METALLURGISTS ASSIGNMENT / ASIGNACIÓN: 11 – Electroref!! / Electroref!#c$! LE%EL/ NI%EL: I!ter&e'#te/ I!ter&e'oNAME/ NOM(RE:))))))))))))))))))))))))))))))))))*** INSTRUCTIONS:  Translate this text into Spanish +#r# r#+, -. +#r# r#+, .  Send your translation version !tl  : Octo-er 10 t,   22:33 +& . INSTRUCCIONES:  Realizar la traducción del texto al español +4rr#fo +or +4rr#fo .  Enviar su versión de traducción ,#5t#: 10 'e Oct-re 22:33 +&*  _______________________________________________________________ 1*Tr#!5l#te t,e follo6! te7t* / Tr#'cr el 5 e!te te7to* Some of the recent developments that have led to increases in production andcathode quality have been reusable cathodes improved electrolytic bleeds monitorin! of additives periodic current reversal and anode preparation machines. Re5#-le C#t,o'e5 rom the early days of electrorefinin! copper starter sheets have been used asthe cathode. The sheets are electro#on from stripper cells usually #ithin the refinery.These thin sheets can create difficulties due to #arpin! or bendin!. $n recent years theuse of reusable starter sheets of titanium and stainless steel has become prevalent.%opper is electrodeposited on the mother plate for a suitable time typically &'() days.The copper is then removed usually by a mechanical strippin! machine. ollo#in! a www.intermetperu.com  visual inspection the starter sheets are returned to electrorefinin! cells.Stainless steel technolo!y has been !ro#in! in popularity compared to titaniumbecause of the si!nificantly lo#er initial capital expenditure. There are t#o differentstainless steel technolo!ies the $S* process and the +idd ,rocess. The ma-or differencebet#een the methods is on the bottom of the cathode. The $S* process uses #ax toprevent copper deposition and thus produces t#o cathode sheets one on each side ofthe stainless steel blan/0. The +idd ,rocess leaves the bottom exposed #hich createst#o sheets connected at the bottom. The ma-or advanta!es of the stainless steeltechnolo!y over traditional copper starter sheets are the avoidance of starter sheetmanufacturin! and improved verticality. $mprovements to the verticality of the cathodehave led to fe#er shorts !reater current densities and purer cathodes. Electrol.te (lee'5 1hile the removal of impurities from the electrolyte has been practiced for manydecades there have been some recent chan!es in the removal method. Traditionally thebleedin! of impurities involves the use of liberator cells. $n a liberator cell there areseveral sta!es of electro#innin! follo#ed by crystallization. The electro#innin! sta!esremove copper and the 2roup 34 elements *s Sb and 4i0. The first electro#innin! stepusually deposits a fairly pure copper product. The second and sometimes thirdelectro#innin! sta!e removes %u *s Sb and 4i. ollo#in! electro#innin! the solution isheated to evaporate #ater and thus crystallize nic/el cobalt and iron as sulfates.The removal of *s Sb and 4i from the bleed streams usin! solvent extraction andchelatin! resins has received considerable attention #ithin the last t#enty five years.5oey et al. indicated that solvent extraction can be utilized for as removal #ith a finalsalable product of bicupric arsenate #hich is a precursor for chrome copper arsenate alumber preservative. Rondas et al. revie#ed the solvent extraction of arsenic #ith T4, www.intermetperu.com   #hich has been employed at 6nion 7iniere since (8&). erric ions hinder the arsenicremoval by T4, because of an undefined relationship bet#een *s9 and e;. Shibata et al. related the ability of 6R';;<< a chelatin! resin manufactured by6niti/a %o. to remove Sb and 4i selectively from commercial electrolyte. * final product ofantimony chloride and bismuth chloride is produced by strippin! the resins #ith = > 5%l.?reisin!er and Scholey performed laboratory studies on t#o phosphonic acid basedresins 6R';;<< and %')=& indicatin! a process to minimize ferric loadin! on to theresins. Sasa/i reported usin! another chelatin! resin for Sb removal. The resin #asE,@R6S 7A'B produced by 7iyoshi @il and at %o. Ctd. and could be used #ith a B') 75%l strippin! solution. Toyabe et al. demonstrated that activated carbon can also be usedto absorb antimony from the electrolyte. The loaded activated carbon is used as areducin! a!ent in a furnace #ithin the silver refinery attached to the copper refinery. A''t8e Mo!tor! *dditives such as chloride thiourea !lue and *vitone are used extensively inelectrorefinin! as !rain refiners and levelin! a!ents for deposition. They allo# theproduction of smooth dense cathodes #hich #ill not encapsulate impurities either in theelectrolyte or secondary phases. 1hile additives have been used for many decades themonitorin! of these has only recently been employed. The development of the Reatrol,rocess by *sarco to monitor thiourea and the %olla7at system for !lue by >orddeutsche*ffiniere have led to substantial improvements in deposition consistency and improvedcurrent efficiency. The Reatrol ,rocess is a patented technique #hich utilizes differentialpulse polaro!raphy to ascertain the active concentration of thiourea by complexation #itha droppin! mercury electrode. $t is said to be accurate to (<< ppb of thiourea. *disadvanta!e #ith the Reatrol ,rocess is that it is an off'line measurement. The %olla7etsystem is a proprietary real'time !lue monitorin! apparatus. There has been no literatureon the details of the system except that it is based on evaluation of potential. www.intermetperu.com  Pero'c Crre!t Re8er5#l  ,eriodic current reversal ,%R0 is bein! employed in at least (( refineries toincrease the rate of cathode production by increasin! the applied current density. ,%R isa method by #hich a for#ard current is applied for a len!th of time follo#ed by a quic/current reversal. The for#ard to reverse period ratio is typically bet#een B<D( to ;<D(. Thereversal of current allo#s for hi!her current densities to be employed #ithout causin!anode passivation. The advanta!e arises from the reversal current depletin! the built upcopper concentration #ithin the anodic boundary layer. This helps avoid the precipitationof copper sulfate #hich is one of the causes of passivation. ?epletin! the copperconcentration also affects the localized p5 #hich can si!nificantly affect the stability ofcopper oxide films another cause of passivation. The ma-or disadvanta!e of ,%R ishi!her ener!y costs. This has limited the use of this technolo!y. A!o'e Pre+#r#to! M#c,!e5 *node preparation machines are !ro#in! in usa!e by allo#in! !reater currentdensities decreasin! shorts and decreasin! dama!e to the electrolytic cells. This iscaused by the improved verticality caused by pressin! and lu! machinin! and !reatercontrol of anode physical dimensions and #ei!ht. *node preparation machines are no#found in B; of the 9; electrorefineries reported in Schloen and ?avenports most recentsurvey.*node preparation machines usually consist of at least five critical components: (0receivin! station B0 anode #ei!hin! unit ;0 anode press )0 lu! press and millin! and 90spacin! conveyor. The receivin! station is #here the anodes are loaded into the processstream of the electrorefinery. This is typically done #ith a for/lift or straddle car. Theanodes are then #ei!hed. *nodes #ith out'of'spec #ei!ht are returned for re'castin!. 4ycontrollin! the anode #ei!ht shorts are minimized and post'refinery scrap is minimized. www.intermetperu.com
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