| 摘要 |
<p>PURPOSE:To efficiently and easily remove lead from molten cast iron at low cost by blowing inert gas in the molten cast iron as bubble-state. CONSTITUTION:The cast iron is heated and melted in a insulating fire brick- made electric furnace 1. The inert gas is blown into this molten cast iron 2 through a gas blowing pole 3 composed of a lance boring multiple small holes 3a. As this gas, Ar gas or N2 gas, etc., is suitable. The above gas is made to fine bubbles in the molten metal 2 and uniformly injected and raised. By this method, area of gas-liquid interface related to evaporation of the lead in the molten metal 2 is widened and shifting distance of the lead in the molten cast iron is shortened, and the lead is efficiently shifted into bubbles and removed.</p> |
