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Title: Removal of impurities from dry scrubbed fluoride enriched alumina

Book ·
OSTI ID:371982
 [1];  [2]
  1. ABB Corporate Research Center, Heidelberg (Germany)
  2. ABB Environmental, Oslo (Norway)

The pot-gas from an aluminum electrolytic cell is cleaned by a dry scrubbing process using fresh alumina as a scrubbing agent. This alumina is enriched with fluorides and trace impurities in a closed loop system with the pots. The only significant removal of the impurities is due to metal tapping. An improved technique has been developed that is more effective than earlier stripper systems. The impurity-rich fine fraction (< 10 {micro}m) of the enriched alumina is partly attached to the coarser alumina. That attachment has to be broken. Selective impact milling under special moderate conditions and air classifying have shown to be a cost effective process for the removal of impurities. For iron (Fe) and phosphorus (P) about 30--70% can be removed by the separation of 0.5--1% of the alumina. Full scale tests have successfully confirmed these results.

OSTI ID:
371982
Report Number(s):
CONF-960202-; ISBN 0-87339-312-0; TRN: IM9641%%59
Resource Relation:
Conference: Annual meeting and exhibition of the Minerals, Metals and Materials Society (TMS), Anaheim, CA (United States), 4-8 Feb 1996; Other Information: PBD: 1996; Related Information: Is Part Of Light metals 1996; Hale, W. [ed.] [Anglesey Aluminum Metal Ltd., North Wales (United Kingdom)]; PB: 1304 p.
Country of Publication:
United States
Language:
English