Atthe Iscor (Vanderbijlpark) works, tin issmelted from a cassiterite concentrate in a submergedarc furnace with apower input of350kVA,the electrodes being amplidyne controlled. Thesidewall ofthefurnace islined with fireclay bricks andthe hearth with carbon blocks. The waste gas, which issucked offround the perimeter ofthefurnace, iscollected ...