Removing Bismuth from Lead with a Submersible Centrifuge

Details

• Personal Author:
  Montagna, D. ; Ruppert JA
• Description:
  The kroll-betterton process for debismuthizing lead is based on adding calcium and magnesium to impure molten bullion to form solid ca-mg-bi intermetallic compounds that float on the surface as drosses. Present practice in industry is to hand-skim off these drosses, often followed by hydraulic pressing to squeeze out some of the entrapped liquid lead. In an effort to develop an improved technique, the use of an argon-shrouded dipping centrifuge to perform the required phase separation was investigated. Centrifugation experiments demonstrated that the bismuth content of an impure bullion could be lowered from an initial 0.5 percent down to 0.03 percent with a lead recovery of 90 percent, which is comparable to lead recovery after hand skimming of drosses in commercial lead-debismuthizing operations. Centrifugation provides better control in removing drosses, faster operation with less oxidation and relatively little fuming, and recovery of a lead bullion that approaches commercial specifications. [Description provided by NIOSH]
• Subjects:
  Occupational Health Safety
• Series:
  Mining Publications
• Subseries:
  Report of Investigations
• Document Type:
  Text
• Genre:
  Conference Publications ; Case Report
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  CPRC - College Park Metallurgy Research Center
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  1-10
• NIOSHTIC Number:
  nn:10008836
• NTIS Accession Number:
  PB-208005
• Citation:
  NTIS: PB 208 005 :10 pages
• Federal Fiscal Year:
  1972
• Peer Reviewed:
  False
• Source Full Name:
  NTIS: PB 208 005
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:bed6864d7d7a3e117d919f5cabfde60c73adf048ce17e8c2fc3b81552c0424cfb6305e2bd131f6addb1d817b70fca64f88b2112c0c665fb1305ee7bcad04e0f2
• Download URL:
  https://stacks.cdc.gov/view/cdc/233873/cdc_233873_DS1.pdf
• File Type:
  [PDF - 5.46 MB ]