title: Rendering wastes obtained from gold analysis by the lead-fusion fire-assay method non-hazardous.
abstract: The classical method of melting lead by fire-assay (Pb-FA) is the most frequently used analytical technique in gold prospection. The crucible solid waste which is generated in this process is usually characterized by chemical and mineralogical composition, granulometric size distribution, and classified according to Brazilian Environmental Regulations. This study demonstrates how acid leaching can be used to remove lead from waste originally classified as hazardous by treatment with hydrochloric and nitric acids followed by chemical precipitation in sodium metasilicate solution. It is shown that for every 1000 kg of hazardous waste, 995.6 kg of non-harzardous waste can be recovered.
authors: SGS GEOSOL Laboratories Ltd., 33200-000 Vespasiano, MG, Brazil.
authors: Fernanda Batalha
authors: FB
authors: Magalhães
authors: Cornélio
authors: C
authors: de Freitas Carvalho
authors: Eduardo Lyse
authors: EL
authors: Corrêa Netto Carvalho
authors: Maria Irene
authors: MI
authors: Yoshida
authors: Cláudio
authors: C
authors: Gouvêa dos-Santos
mesh_terms: D001938:Brazil; D006046:Gold / Q000032:analysis; D006256:Hazardous Waste / Q000032:analysis*; D007220:Industrial Waste / Q000032:analysis; D007854:Lead / Q000737:chemistry*; D008906:Mining; D012037:Refuse Disposal / Q000379:methods*; D062611:Solid Waste / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*
chemical_list: D006256:Hazardous Waste; D007220:Industrial Waste; D062611:Solid Waste; D014874:Water Pollutants, Chemical; D007854:Lead; D006046:Gold