Leaching of metal(loid)s from ashes of spent sorbent and stabilisation effect of calcium-rich additives
Autor: | Marcus Öhman, Alfreda Kasiuliene, Hamid Sefidari, Prosun Bhattacharya, Jurate Kumpiene, Ivan Carabante |
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Rok vydání: | 2020 |
Předmět: |
Sorbent
Health Toxicology and Mutagenesis Lime Thermochemical equilibrium calculations chemistry.chemical_element Incineration 02 engineering and technology 010501 environmental sciences engineering.material Coal Ash 01 natural sciences Arsenic Hazardous waste Metals Heavy Environmental Chemistry Leachate 0105 earth and related environmental sciences Minerals Waste management General Medicine Iron-coated peat Contamination 021001 nanoscience & nanotechnology Pollution Refuse Disposal Waste Disposal Facilities Heavy metals chemistry engineering Environmental science Calcium Leaching (metallurgy) 0210 nano-technology Research Article |
Zdroj: | Environmental Science and Pollution Research International |
ISSN: | 1614-7499 0944-1344 |
Popis: | Contaminated water with multiple contaminants, including As, Cr, Cu and Zn, was treated with a sorbent prepared by coating peat with Fe oxides. Because As has a relatively little explored market, the regeneration of the spent sorbent was not feasible. Meanwhile, the disposal of As wastes in landfills can cause landfill leachate treatment problems. Under the reducing conditions prevailing at landfills, As(V) is reduced to As(III), which is a toxic and more mobile form. In this study, incineration was explored as a management option to treat the spent sorbent that was loaded with As, Cr, Cu and Zn. The first objective of this study was to evaluate the leaching of these metal(loid)s from the ashes and compare it with the leaching from the spent sorbents before incineration. The second objective was to evaluate the leaching behaviour when the spent sorbent was co-incinerated with a Ca-rich additive (lime). To achieve these objectives, the obtained ashes were subjected to leaching tests, sequential extraction, and X-ray diffraction analyses. After the incineration, the ash content ranged from 9 to 19% of the initial mass of the spent sorbents. The leaching of As, Cu and Zn decreased compared with that from the spent sorbents before the thermal treatment because of the high incineration temperatures and/or co-incineration with lime. However, the leaching of Cr increased, which would hinder the disposal of the obtained ashes in a landfill because the limit value for disposal at a landfill for hazardous wastes was exceeded by 50 times. However, co-incineration with 10 wt% lime significantly decreased the leaching of Cr as a result of the formation of water-insoluble Ca-Cr compounds. Electronic supplementary material The online version of this article (10.1007/s11356-020-09269-z) contains supplementary material, which is available to authorized users. |
Databáze: | OpenAIRE |
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