About Rotary Furnace The Rotary Melting Furnace is a very flexible and universal equipment used for recycling many non-ferrous metals. It is the major lead production technology used in India and many other countries for Secondary Lead Production. A lead production system based on this technology has certain distinct characteristics such as: •Equipment scalable for installing higher capacities •Recovers all lead in one production cycle •Plates & powder from scrap battery as well as slag from Mini Blast Furnace can be used as raw material •Requires addition of certain consumables •Can be fired with various fuels •Generates high Pollution both as Flue Gases & Fugitive Emissions Description of Rotary Furnace It is a Rotary kiln in the form of a metallic cylinder with conical sides on both ends. Mild steel plate is used for construction of this shell and its thickness varies depending upon the capacity of the equipment. This shell is rotated on its own axis at 1-2 rpm. For this purposes tyres (also called riding rings) are fitted on the shell. These are fabricated from MS squares or flats, machined for a smooth finish. These tyres ride on steel rollers which are again machined finely. These rollers are fitted on a robust MS structural frame and driven by a gear & motor arrangement. The shell is lined inside with insulation and fire bricks of suitable Alumina content. Conical ends of the furnace are open on both sides. The furnace is charged with Raw material along with additives from the front end. This side is provided with a movable door on which a burner is mounted. The burner can be a conventional one or a fully automatic one depending upon the fuel used. At the other end, an exhaust block lined with refractory bricks is provided. A tapping hole is provided in the center of the shell from where molten metal & slag are discharged. Flue gases generated are sucked from the exhaust block side of the furnace. A typical 3.0 TpB Rotary Furnace has the following standard sizes & specifications : •Outside dimensions of the Rotary •Shell dia : 2075mm •Shell length : 2500mm •Total length : 4500mm •Charging dia : 450mm •Exhaust side dia : 450mm •Refractory thickness : 200mm •Fuel : Furnace Oil •Burner : Model 4 A Make: Wesman with complete assembly •FD Fan capacity : 550 cmh at 44mm of WG •Gear Box in drive : 8”, 1:40 Ratio •Motor in drive : 15.0 HP x 960 RPM •Structure used for base : ISMC 250 x 80 Advantages •Recovers 100% lead in the first operation. •Slag produced is lead free. •Equipment can be scaled up for higher production capacities. Disadvantages •Many chemicals are required for operation. •High power consumption. •Difficult to produce low Antimony lead suitable for soft lead purposes. •Fugitive Emissions need to be captured in addition to flue gases. •Need skilled operators and careful maintenance.
