Stabilization Study of a Contaminated Soil with Metal(loid)s Adding Different Low-Grade MgO Degrees
| Autor: | Joan Formosa, J. Giro-Paloma, Josep Maria Chimenos |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Soil stabilization
Recuperació de residus percolation column test Environmental remediation Soil pollution Geography Planning and Development TJ807-830 polluted soil LG-MgO Òxid de magnesi Contaminació dels sòls 010501 environmental sciences Management Monitoring Policy and Law engineering.material TD194-195 01 natural sciences Renewable energy sources chemistry.chemical_compound GE1-350 Solubility Recovery of waste products Magnesium oxide 0105 earth and related environmental sciences Lime Environmental effects of industries and plants soil stabilization Renewable Energy Sustainability and the Environment Chemistry Estabilització de sòls 04 agricultural and veterinary sciences Soil contamination Environmental sciences waste valorization batch leaching test Environmental chemistry magnesium oxide by-products Soil water 040103 agronomy & agriculture engineering 0401 agriculture forestry and fisheries Hydroxide Leaching (metallurgy) |
| Zdroj: | Dipòsit Digital de la UB Universidad de Barcelona Sustainability Volume 12 Issue 18 Sustainability, Vol 12, Iss 7340, p 7340 (2020) |
| ISSN: | 2071-1050 |
| DOI: | 10.3390/su12187340 |
| Popis: | Low-grade magnesium oxide (LG-MgO) was proposed as ordinary Portland cement (OPC) or lime substitute (CaO) for metal(loid)s remediation in contaminated soils. Some metal(loid)s precipitate at pH &asymp 9 in insoluble hydroxide form thus avoiding their leaching. LG-MgO avoids the re-dissolution of certain metal(loid)s at 9.0 < pH < 11.0 (pH-dependents), whose solubility depends on the pH. A highly contaminated soil with heavy metal(loid)s was stabilized using different LG-MgO by-products sources as stabilizing agents. Two of the three studied LG-MgOs were selected for the stabilization, by mixing 5, 10, and 15 wt.%. The effect of using LG-MgO not only depends on the size of the particles, but also on those impurities that are present in the LG-MgO samples. Particle size distribution, X-ray fluorescence (XRF), X-ray diffraction (XRD), thermogravimetric analysis, citric acid test, specific surface, bulk density, acid neutralization capacity, batch leaching tests (BLTs), and percolation column tests (PCTs) were techniques used to deeply characterize the different LG-MgO and the contaminated and remediated soils. The remediation&rsquo s results efficacy indicated that when the medium pH was between 9.0 and 11.0, the concentration of pH-dependent metal(loid)s decreases significantly. Although around 15 wt.% of a stabilizing agent was appropriate for the soil remediation to ensure an alkali reservoir that maintains optimal stabilization conditions for a long period, 5 wt.% of LG-MgO was enough to remedy the contaminated soil. When evaluating a polluted and decontaminated soil, both BLTs and PCTs should be complementary procedures. |
| Databáze: | OpenAIRE |
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