title: Mineral phases and metals in baghouse dust from secondary aluminum production.
abstract: Baghouse dust (BHD) is a solid waste generated by air pollution control systems during secondary aluminum processing (SAP). Management and disposal of BHD can be challenging in the U.S. and elsewhere. In this study, the mineral phases, metal content and metal leachability of 78 BHD samples collected from 13 different SAP facilities across the U.S. were investigated. The XRD semi-quantitative analysis of BHD samples suggests the presence of metallic aluminum, aluminum oxide, aluminum nitride and its oxides, spinel, elpasolite as well as diaspora. BHD also contains halite, sylvite and fluorite, which are used as fluxes in SAP activities. Total aluminum (Al) in the BHD samples averaged 18% by weight. Elevated concentrations of trace metals (>100 μg L(-1) As; >1000 μg L(-1) Cu, Mn, Se, Pb, Mn and Zn) were also detected in the leachate. The U.S. toxicity characteristic leaching procedure (TCLP) results showed that some samples leached above the toxicity limit for Cd, Pb and Se. Exceeding the TCLP limits in all sample is independent of facilities generating the BHD. From the metal content perspective only, it appears that BHD has a higher potential to exhibit toxicity characteristics than salt cake (the largest waste stream generated by SAP facilities).
authors.affiliation: Pegasus Technical Services, Inc., 46 E. Hollister Street, Cincinnati, OH 45219, USA.
authors.forename: Xiao-Lan
authors.initials: XL
authors.lastname: Huang
authors.affiliation: Pegasus Technical Services, Inc., 46 E. Hollister Street, Cincinnati, OH 45219, USA.
authors.forename: Amro M
authors.initials: AM
authors.lastname: El Badawy
authors.affiliation: Pegasus Technical Services, Inc., 46 E. Hollister Street, Cincinnati, OH 45219, USA.
authors.forename: Mahendranath
authors.initials: M
authors.lastname: Arambewela
authors.affiliation: Pegasus Technical Services, Inc., 46 E. Hollister Street, Cincinnati, OH 45219, USA.
authors.forename: Renata
authors.initials: R
authors.lastname: Adkins
authors.affiliation: Office of Research and Development, U.S. EPA, Cincinnati, OH 45224, USA. Electronic address: tolaymat.thabet@epamail.epa.gov.
authors.forename: Thabet
authors.initials: T
authors.lastname: Tolaymat
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000535:Aluminum / Q000032:analysis*; D017607:Aluminum Compounds / Q000032:analysis; D000537:Aluminum Oxide / Q000032:analysis; D004391:Dust / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods; D005740:Gases; D007220:Industrial Waste; D007221:Industry; D008277:Magnesium Oxide / Q000032:analysis; D008670:Metals / Q000032:analysis; D008903:Minerals / Q000032:analysis; D012037:Refuse Disposal / Q000379:methods; D014131:Trace Elements / Q000032:analysis; D014481:United States; D014961:X-Ray Diffraction
chemical_list: D000393:Air Pollutants; D017607:Aluminum Compounds; D004391:Dust; D005740:Gases; D007220:Industrial Waste; D008670:Metals; D008903:Minerals; D014131:Trace Elements; C111130:spinell; D008277:Magnesium Oxide; C052045:aluminum nitride; D000535:Aluminum; D000537:Aluminum Oxide
keywords: Aluminum; Baghouse dust (BHD); Landfill; Secondary aluminum production (SAP); Toxicity characteristic leaching procedure (TCLP)