Abstract
This paper studied the migration, transformation, leaching toxicity, and risk assessment of heavy metals when oily sludge was pyrolyzed at multiple pyrolysis temperatures and residence times. Results indicated that heavy metals were enriched in char, while less than 3% of heavy metals were distributed to gas and liquid products. By the modified European Community Bureau of Reference sequential extraction method, it was found that the most immobilized Cr, Ni, and Pb were obtained under conditions of 600 °C for 30 min, 400 °C for 60 min, and 500 °C for 60 min, respectively. However, pyrolysis reduced the percentage of stable fractions in Cu and Zn. Similarly, the leaching concentrations of Cr, Ni, and Pb decreased through pyrolysis, while that of Zn increased. Risk assessment code results suggested that pyrolysis reduced the environmental risk of Pb but increased that of Zn. Meanwhile, the mechanism of heavy metal migration and transformation was explored by characterizing with proximate analysis, ultimate analysis, X-ray fluorescence, Fourier transform infrared spectroscopy, and X-ray diffraction. The results indicated that aromatization and mineral crystals in chars influenced the immobilization of heavy metals.
Original language | English |
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Pages (from-to) | 8311-8322 |
Number of pages | 12 |
Journal | Energy and Fuels |
Volume | 36 |
Issue number | 15 |
Early online date | 15 Jul 2022 |
DOIs | |
Publication status | Published - 04 Aug 2022 |
Externally published | Yes |
Bibliographical note
Funding Information:This project has received funding from the Key R&D plan of Shaanxi Province (No.2021GY-114), State Key Laboratory of Coal Combustion (No.FSKLCCA2107), Science and Technology Exchange Project of China Ministry of Science and Technology (No.2021-12-2), Education Cooperation Project between China and Central Eastern European Countries (No.2021086), and Shaanxi Provincial Natural Science Foundation Research Program-Shaanxi Coal Joint Funding (No.2019JLZ-12).
Publisher Copyright:
© 2022 American Chemical Society. All rights reserved.
ASJC Scopus subject areas
- General Chemical Engineering
- Fuel Technology
- Energy Engineering and Power Technology