IDEX Scrap Decoater and Dryer
A demonstration to decoat oily scrap aluminum for the secondary and primary aluminum industry has been completed at Wabash Alloy (formerly Roth Bros.) in East Syracuse, NY. The equipment, termed IDEX, compared to conventional equipment, results in a 56% reduction in energy use, reduction in emissions (including volatile organic compounds), dust formation and an increase in production. The figure below shows a photograph of the IDEX installed at Wabash. Scrap is first fed into a sealed rotating kiln and the scrap oils are vaporized by a 1500 of counter flowing gas stream with low oxygen content. The gas stream is next passed to an incinerator to combust the oils. Part of the gas returns to the kiln completing the cycle. The heat release from the oils provide all the heat needed to drive the process. Further, since the oxygen content is kept below the oil's lower flammability limits, combustion in the kiln is not possible, which further protects the metal.
The subsequent 2 figures show the large flames and billowing smoke from a furnace melting scrap that is conventionally decoated and dried. The last figure is a photograph from the same furnace melting scrap decoated by the IDEX system. The large reduction in flames and smoke indicate a lower level of contaminants in the melt.
The emissions of the IDEX are shown in the following table along with a comparison to NY State’s requirements.
The emissions are well below those regulations with NOx, SO2, VOC, and particulates at 19%, 2%, 2%, and 6% respectively of the standard.