Show 4 tootles To new slag plant 11 i 01 1 11 nl I 1 1 4 C the basic purposes ot at the slag tr treatment plant la is to recover from lead abad blast bias furnace slag blag zinc that la Is now being wasted on the dump its offset commercially will be the recovery of the greater part ot of the zinc line that la Is now being lost la in the ameeti f melting 9 of ordinary lead ores ore oreland sand and thus add nad to current na national t lonal zinc production brodu c tion of 0 f from to pounds monthly from e alone alona zinc has always been an element that increases cost in lead blast furnace furnaca smelting smelling sm elting and will still continue to be therefore the value of 0 we this operation is entirely in the recovery of such zinc line and in no way affects the cost ot of putting it through the blast furnace ur by such zinc recovery it Is hoped finally as soon as the economics ot of tho the whole operation are worked out to bo be able to treat lead ores much higher in zinc than at the tha present time and hence increase the commercial limit ot of tricky lead ores particularly those which due to more or less exida tion or other causes are not amenable to treat treatment men t by selective flotation incidentally it will be possible to recover zinc from slag dumps which are sufficiently high in zinc to warrant their treatment re such slag alag can either be handled by putting it cold into the slag treatment furnace or by melting first through the tha lead blast furnace tho the choice between the two will be dictated by conditions in each case the tha metallurgy of at this process was worked worded out at tofele tooele some eoma 15 years ago under patents granted to U A garred which were acquired by international Sm smelling elting refining company and its associated socia ted companies A furnace ot at this typo type was installed br t the lie anaconda copper mining company to treat tho the slag lag from the american smelting smelling Sm elting refining kenning corn com east helena plant some 12 to it 31 years ago the process consists of blow blowing I 1 nn air and pulverized coal through molten slag in a furmage of 0 tho tha blast type the zinc la Is reduced and immediately ro re oxidized in tho the upper part of the furnace forming an fume any residual lead la is also reduced and the lead again re oxidized in the tha upper part ot of the furnace the gas gag from the turnice furnace containing the tha fume tainie Is cooled and lead to a bag house where a zinc tume fume containing some soma lead leaa is produced inasmuch as tume funte with as little lead a aa possible la Is preferred by the retort plants for the manufacture of 0 prime western zinc the leady zinc fume IV will 11 be passed through a rotary id win n for the elimination ol of the ie lend a which will in turn he be caught as a a lead tune fume in a separate bag house houe the de leaded fume will be shipped to eastern refineries refiner loi and the lead returned to the lead blast furnice turnce here |