TY - THES

T1 - Determination of Antimony Saturation in Harris Slags

AU - Zummar Ghazaleh, Shady Jose

N1 - embargoed until 10-10-2027

PY - 2022

Y1 - 2022

N2 - An increase of 22 % in lead usage is expected in the European Union by 2050. The Harris process is a critical step during lead refining in which a salt melt is used to remove arsenic, tin and antimony. To further automate lead refining and improve safety, developing a reliable and replicable method to determine when the melt, known as the Harris slag, is saturated with impurities, and must be replaced is critical. To achieve this, a literature review of lead metallurgy focusing on the Harris process was executed. Antimony containing industrial Harris slag samples were collected and characterization was performed. Two different methods to determine the saturation of Harris slags were proposed relying on the viscosity and electrical conductivity of the slag. The physical fundamentals of the proposed techniques were discussed, and experimentally investigated using the industrial samples along with lab-prepared synthetic counterparts. Rheometric measurements displayed non-revisable time dependent behavior suggesting physical changes in the material when sheared casting doubt on viscosity as a reliable signal of antimony saturation. Contrastingly, electrical conductivity showed promise as it decreased with increasing antimony content. Recommendations are made herein to further develop the electroconductivity technique and address encountered issues.

AB - An increase of 22 % in lead usage is expected in the European Union by 2050. The Harris process is a critical step during lead refining in which a salt melt is used to remove arsenic, tin and antimony. To further automate lead refining and improve safety, developing a reliable and replicable method to determine when the melt, known as the Harris slag, is saturated with impurities, and must be replaced is critical. To achieve this, a literature review of lead metallurgy focusing on the Harris process was executed. Antimony containing industrial Harris slag samples were collected and characterization was performed. Two different methods to determine the saturation of Harris slags were proposed relying on the viscosity and electrical conductivity of the slag. The physical fundamentals of the proposed techniques were discussed, and experimentally investigated using the industrial samples along with lab-prepared synthetic counterparts. Rheometric measurements displayed non-revisable time dependent behavior suggesting physical changes in the material when sheared casting doubt on viscosity as a reliable signal of antimony saturation. Contrastingly, electrical conductivity showed promise as it decreased with increasing antimony content. Recommendations are made herein to further develop the electroconductivity technique and address encountered issues.

KW - Harris Slags

KW - Caustique Slags

KW - Caustic Slags

KW - Harris Melts

KW - Harris Process

KW - Harris

KW - Antimony Saturation

KW - Electrical Conductivity

KW - Viscosity

KW - Electroconductivity

KW - Lead

KW - Lead Refining

KW - Antimony

KW - Arsenic

KW - Tin

KW - Sb

KW - Pb

KW - Sn

KW - As

KW - Umicore

KW - Harris-Schlacken

KW - kaustische Schlacken

KW - Harris-Schmelzen

KW - Harris-Verfahren

KW - Harris

KW - Antimonsättigung

KW - elektrische Leitfähigkeit

KW - Viskosität

KW - Blei

KW - Bleiraffination

KW - Antimon

KW - Arsen

KW - Zinn

KW - Sb

KW - Pb

KW - Sn

KW - As

KW - Umicore

M3 - Master's Thesis

ER -