Abstract
Acid treatment can increase the sludge calorific value to some extent by separating inorganic elements. In order to determine the mechanism by which acidification affects the sludge calorific value from an organic perspective, we investigated the changes in organic matter and dewaterability under different pH conditions. The results of this study showed that acidification conditioning retained organic matter while removing a greater amount of inorganic elements. Furthermore, acid treatment significantly increased the zeta potential and particle size of sludge particles and facilitated the precipitation of biological organic components from the supernatant to the surface of sludge particles. Acid-treated sludge exhibited a lower moisture content and a higher proportion of organic matter, and sludge treated with H2SO4, HCl, and HNO3 exhibited respective increases in calorific values of 12.14%, 7.92%, and 8.01% under pH 2. The calorific value of the acid-treated sludge was higher, making it more suitable for subsequent incineration. The findings of this study serve as a reference and foundation for efficient sludge incineration.
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Data Availability
The data that support the fndings of this study are openly available on request.
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This study was financially supported by China Energy Engineering Group Guangdong Electric Power Design Institute Co., Ltd (CG-2021-K-016).
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Lieyang Lv: writing—original draft, writing—review and editing, investigation, methodology, visualization. Meiqi Yang: investigation, data curation, validation. Wei Liu: funding acquisition, conceptualization, supervision.
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Lv, L., Yang, M. & Liu, W. Effects of organic matter and dewaterability changes on sludge calorific value during acid treatment. Environ Sci Pollut Res 31, 2104–2116 (2024). https://doi.org/10.1007/s11356-023-30957-z
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DOI: https://doi.org/10.1007/s11356-023-30957-z