title: Contaminant retention characteristics of fly ash-bentonite mixes.
abstract: It is important to determine the contaminant retention characteristics of materials when assessing their suitability for use as liners in landfill sites. Sand-bentonite mixtures are commonly used as liners in the construction of landfill sites for industrial and hazardous wastes. Sand is considered to be a passive material with a negligible chemical retention capacity; fly ash, however, offers the additional advantage of adsorbing the heavy metals present in landfill leachates. There have been few studies of the contaminant retention characteristics of fly ash-bentonite mixes. The study reported here determined the contaminant retention characteristics of different fly ashes, bentonite and selected fly ash-bentonite mixes for Pb2+using 24 h batch tests. The tests were conducted by varying the initial concentrations of metal ions under uncontrolled pH conditions. The efficiency of the removal of Pb2+by the different types of fly ash and fly ash-bentonite mixes was studied. The influence of multiple sources of fly ash on the retention characteristics of fly ash-bentonite mixes was investigated.
authors.affiliation: 1 Department of Civil Engineering, Central Institute of Technology Kokrajhar, India.
authors.forename: Abhijit
authors.initials: A
authors.lastname: Deka
authors.affiliation: 2 Department of Civil Engineering, Indian Institute of Technology Guwahati, India.
authors.forename: Sreedeep
authors.initials: S
authors.lastname: Sekharan
mesh_terms: D001546:Bentonite / Q000737:chemistry*; D060729:Coal Ash / Q000737:chemistry*; D004785:Environmental Pollutants / Q000032:analysis / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007854:Lead / Q000032:analysis* / Q000737:chemistry; D064091:Waste Disposal Facilities
chemical_list: D060729:Coal Ash; D004785:Environmental Pollutants; D001546:Bentonite; D007854:Lead
keywords: Waste containment; bentonite; contaminant retention; fly ash; landfill; liners