FIELD: metallurgy.
SUBSTANCE: method involves dosing the original tin into a boiler along with pouring in a vacuum chamber onto an evaporation plate, heated by an electric heater, evaporation and condensation of lead vapours on screens and its removal to the receiving condensate bath, draining the purified tin from the evaporation plates and its discharging to the receiving tin bath, while the initial tin boiler a lead concentration potential is measured by submersing an electrode with a lead-containing electrolyte in the tin and, when the potential deviates from the previous value, they decrease or increase the flow of the initial tin, dosed into the vacuum chamber, using a regulator, and a tin concentration potential is measured in the condensate bath by submersing an electrode with a tin-containing electrolyte and, when the potential deviates from the specified value, they increase or decrease the consumption of power for heating evaporation plates by a regulator. As an electrode for measuring the lead concentration potential in the initial tin boiler, a quartz fabric is used in two layers with a gap, in which a lead-containing electrolyte is poured to impregnate the fabric, and which contains, wt ±1%: KCl - 42; NaCl - 7; PbCl2 - 27; ZnCl2 - the rest. As an electrode for measuring the tin concentration potential of the condensate bath, they use a quartz fabric in two layers with a gap for the impregnation of the fabric with tin-containing electrolyte which includes: wt ±1%: KCl - 46; NaCl-8; SnCl2 - 17; ZnCl2 - the rest. The electrode, submersed in the melt for measuring the lead and tin concentration potential, is made of quartz fabric in two layers with a gap, which is filled with electrolyte for impregnation of the fabric and a contact metal plate is inserted therein.
EFFECT: lowering the yield of off-spec tin and condensate and reducing the consumption of power.
6 cl, 3 dwg
