Short Rotary Furnace (SRF)
The Short Rotary Furnace (SRF) is traditionally at the heart of the secondary lead (Pb) recycling plant to provide smelting of the products of spent automotive lead-acid batteries which have gone through a breaking and separation process.
The smelting of metallic lead (grids & poles) and lead pastes (lead oxide & lead sulphate) with reductive reagents results in an antimonial lead bullion which can then be refined and alloyed. Each country has its own emissions and slag regulations, and each secondary lead smelter has its own strategy for generation of saleable by-product. These factors alter the chemical engineering approach to the smelting operation for each and every smelter, and therefore the SRF is sized accordingly, and its configuration is altered to suit the needs of the operation.
The geometric features and benefits of an SRF are;
- Typically the diameter is roughly equivalent to length resulting in a deep bath for high volumetric throughput and high metal recovery.
- Operates usually ~1000°C (1832°F) dependent on process and requires in the region of 10” to 12” refractory typically a high Magnesia-Chrome refractory dependent on the slag system employed. Refractory wear is evenly distributed.
- Fixed axis horizontal rotation at slow speed to provide an even reverbatory heat and mixing of reagents to give a high thermal efficiency and rapid smelting.
- Two ports, one end for burner and process fume extraction, the opposite end is for charging and tapping. Allows a negative pressure at charging port to reduce hygiene when charging, and also allows rapid charging with no obstructions.
- Tapping is through 2 or 3 tapping spouts that require drilling for opening and then blocking up with fireclay once the slag or bullion has been tapped.
- Bi-directional variable speed braked drive units & optional invertor and controls.
- Precision built rolling stock incorporating special steel alloy rollers with integral high load capacity bearings.
- Sturdy machined base frame
- Furnace door, burner and ancillary options to suit application
The Rotary Furnace is suitable for many non-ferrous applications. Long Rotary Furnace options are available with tapping ports to the side or at the front as required.