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Title: Toxicity mitigation and solidification of municipal solid waste incinerator fly ash using alkaline activated coal ash

Highlights: Black-Right-Pointing-Pointer Incinerator fly ash (IFA) is added to an alkali activated coal fly ash (CFA) matrix. Black-Right-Pointing-Pointer Means of stabilizing the incinerator ash for use in construction applications. Black-Right-Pointing-Pointer Concrete made from IFA, CFA and IFA-CFA mixes was chemically characterized. Black-Right-Pointing-Pointer Environmentally friendly solution to IFA disposal by reducing its toxicity levels. - Abstract: Municipal solid waste (MSW) incineration is a common and effective practice to reduce the volume of solid waste in urban areas. However, the byproduct of this process is a fly ash (IFA), which contains large quantities of toxic contaminants. The purpose of this research study was to analyze the chemical, physical and mechanical behaviors resulting from the gradual introduction of IFA to an alkaline activated coal fly ash (CFA) matrix, as a mean of stabilizing the incinerator ash for use in industrial construction applications, where human exposure potential is limited. IFA and CFA were analyzed via X-ray fluorescence (XRF), X-ray diffraction (XRD) and Inductive coupled plasma (ICP) to obtain a full chemical analysis of the samples, its crystallographic characteristics and a detailed count of the eight heavy metals contemplated in US Title 40 of the Code of Federal Regulations (40 CFR). The particle size distributionmore » of IFA and CFA was also recorded. EPA's Toxicity Characteristic Leaching Procedure (TCLP) was followed to monitor the leachability of the contaminants before and after the activation. Also images obtained via Scanning Electron Microscopy (SEM), before and after the activation, are presented. Concrete made from IFA, CFA and IFA-CFA mixes was subjected to a full mechanical characterization; tests include compressive strength, flexural strength, elastic modulus, Poisson's ratio and setting time. The leachable heavy metal contents (except for Se) were below the maximum allowable limits and in many cases even below the reporting limit. The leachable Chromium was reduced from 0.153 down to 0.0045 mg/L, Arsenic from 0.256 down to 0.132 mg/L, Selenium from 1.05 down to 0.29 mg/L, Silver from 0.011 down to .001 mg/L, Barium from 2.06 down to 0.314 mg/L and Mercury from 0.007 down to 0.001 mg/L. Although the leachable Cd exhibited an increase from 0.49 up to 0.805 mg/L and Pd from 0.002 up to 0.029 mg/L, these were well below the maximum limits of 1.00 and 5.00 mg/L, respectively.« less
Authors:
 [1] ;  [1] ; ;  [2] ;  [1]
  1. Alternative Cementitious Binders Laboratory (ACBL), Department of Civil Engineering, Louisiana Tech University, Ruston, LA 71272 (United States)
  2. Department of Chemistry, Louisiana Tech University, Ruston, LA 71272 (United States)
Publication Date:
OSTI Identifier:
21613002
Resource Type:
Journal Article
Resource Relation:
Journal Name: Waste Management; Journal Volume: 32; Journal Issue: 8; Other Information: DOI: 10.1016/j.wasman.2012.03.030; PII: S0956-053X(12)00141-9; Copyright (c) 2012 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 12 MANAGEMENT OF RADIOACTIVE WASTES, AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES; ARSENIC; BARIUM; CHROMIUM; COAL; COMPRESSION STRENGTH; CONCRETES; CRYSTALLOGRAPHY; FLEXURAL STRENGTH; FLY ASH; HEAVY METALS; ICP MASS SPECTROSCOPY; LEACHING; MERCURY; PARTICLE SIZE; SCANNING ELECTRON MICROSCOPY; SELENIUM; SILVER; SOLID WASTES; URBAN AREAS; X-RAY FLUORESCENCE ANALYSIS AEROSOL WASTES; ALKALINE EARTH METALS; ASHES; BUILDING MATERIALS; CARBONACEOUS MATERIALS; CHEMICAL ANALYSIS; COMBUSTION PRODUCTS; DISSOLUTION; ELECTRON MICROSCOPY; ELEMENTS; ENERGY SOURCES; FOSSIL FUELS; FUELS; MASS SPECTROSCOPY; MATERIALS; MECHANICAL PROPERTIES; METALS; MICROSCOPY; NONDESTRUCTIVE ANALYSIS; RESIDUES; SEMIMETALS; SEPARATION PROCESSES; SIZE; SPECTROSCOPY; TRANSITION ELEMENTS; WASTES; X-RAY EMISSION ANALYSIS