Application of municipal sludge biochar in wastewater adsorption treatment

With the rapid development of economic globalization, the amount of sludge discharged from municipal wastewater treatment is increasing, and the annual production of municipal sludge is expected to exceed 9.0×107 t by 2025 in China. The pathogenic microorganisms, organic matter and heavy metals contained in municipal sludge can cause serious harm to the environment and human health. Sludge-derived biochar materials have been widely used in wastewater treatment, achieving the dual purpose of solid waste reuse and pollutant removal due to their large specific surface area, abundant pore structure and rich oxygen-containing groups. In addition, a win-win situation between ecology and development by treating waste with waste can be obtained. In this review, the preparation and modification methods of municipal sludge biochar were summarized, followed by analysis and discussion on the influence factors on adsorption as well as the application and adsorption mechanism of municipal sludge biochar in adsorbing heavy metals, dyes, inorganic salts, antibiotics, and phenols. Finally, the future development and the problems to overcome were discussed, while green low-carbon resource treatment system was considered to be the key for sustainable development. © 2024 Fine Chemicals. All rights reserved.