Coal fly ash interaction with environmental fluids: Geochemical and strontium isotope results from combined column and batch leaching experiments |
| |
| Institution: | 1. Department of Geology & Planetary Science, University of Pittsburgh, Pittsburgh, PA 15260, USA;2. National Energy Technology Laboratory, U.S. Department of Energy, 626 Cochrans Mill Rd., Pittsburgh, PA 15236, USA;3. Department of Geology & Geography, West Virginia University, Morgantown, WV 26506, USA;1. University of Barcelona, Spain;2. U.S. Geological Survey, Menlo Park, CA USA;1. International Water Management Institute, c/o ICRISAT, Patancheru 502 324, Andhra Pradesh, India;2. BRGM, Indo-French Centre for Groundwater Research, Uppal Road, Hyderabad, India;3. National Geophysical Research Institute, Indo-French Centre for Groundwater Research, Uppal Road, Hyderabad, India;4. BRGM, 3 Av. Claude Guillemin, 45060 Orléans, France;1. Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel;2. Israel Hydrological Service, Israel Water Authority, Jerusalem, 9195024, Israel;1. BRGM, D3E/NRE, Indo-French Centre for Groundwater Research, Hyderabad, India;2. BRGM, D3E/GDR, 3 Av. Claude Guillemin, 45 060 Orléans, France;3. BRGM, D3E/NRE, 1034 rue de Pinville, 34 000 Montpellier, France;4. BRGM, LAB/ISO, 3 Av. Claude Guillemin, 45 060 Orléans, France;5. CSIR-National-Geophysical Research Institute, Indo-French Centre for Groundwater Research, Hyderabad, India;1. Department of Geology and Planetary Science, University of Pittsburgh, Pittsburgh, PA 15260, USA;2. National Energy Technology Laboratory, Pittsburgh, PA 15236, USA;3. Department of Geological Sciences, Binghamton University, Binghamton, NY 13902, USA;4. Department of Geology and Geography, West Virginia University, Morgantown, WV 26506, USA |
| |
| Abstract: | The major element and Sr isotope systematics and geochemistry of coal fly ash and its interactions with environmental waters were investigated using laboratory flow-through column leaching experiments (sodium carbonate, acetic acid, nitric acid) and sequential batch leaching experiments (water, acetic acid, hydrochloric acid). Column leaching of Class F fly ash samples shows rapid release of most major elements early in the leaching procedure, suggesting an association of these elements with soluble and surface bound phases. Delayed release of certain elements (e.g., Al, Fe, Si) signals gradual dissolution of more resistant silicate or glass phases as leaching continues. Strontium isotope results from both column and batch leaching experiments show a marked increase in 87Sr/86Sr ratio with continued leaching, yielding a total range of values from 0.7107 to 0.7138. For comparison, the isotopic composition of fluid output from a fly ash impoundment in West Virginia falls in a narrow range around 0.7124. The experimental data suggest the presence of a more resistant, highly radiogenic silicate phase that survives the combustion process and is leached after the more soluble minerals are removed. Strontium isotopic homogenization of minerals in coal does not always occur during the combustion process, despite the high temperatures encountered in the boiler. Early-released Sr tends to be isotopically uniform; thus the Sr isotopic composition of fly ash could be distinguishable from other sources and is a useful tool for quantifying the possible contribution of fly ash leaching to the total dissolved load in natural surface and ground waters. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
