Lead: Secondary Lead Smelter eTool Lead: Secondary Lead Smelter Menu Home Scope Definitions Requirements References Credits Raw Materials Processing Receiving and Storage Battery Breaking/Separating Charge Preparation Handling and Transport Smelting Blast Furnace Reverberatory Furnance Refining and Casting Refining Casting Drossing Environmental Controls Waste Water Controls Dust Collection Systems Maintenance Engineering Controls Local Exhaust Ventilation Diagrams Supplied Air Islands Process Controls Local Exhaust Ventilation Diagrams » Dross Pot Hood Design Characteristics Enclosure to provide capture velocities at openings of 350 - 500 FPM Transport velocities in ducts: ≥ 4000 FPM