Co-treatment of municipal solid waste incineration fly ash (MSWI FA) and municipal sludge: A innovative method to improve sludge dewatering with fly ash dechlorination. (15th April 2023)

• Record Type: Journal Article
• Authors: Xing, Jinxin; Tang, Qingyu; Gan, Min; Ji, Zhiyun; Fan, Xiaohui; Sun, Zengqing; Chen, Xuling
• Is Part Of: Journal of environmental management. Volume 332(2023)
• Publication Date: 2023-04-15
• Subjects: Municipal sludge dewatering -- Municipal solid waste incineration fly ash (MSWI FA) water-washing dechlorination -- Co-treatment -- Chemical conditioning; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2023.117403
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: The complexity of municipal sludge dewatering is a bottleneck problem limiting resource utilization. In this paper, adding municipal solid waste incineration fly ash (MSWI FA) to municipal sludge for enhanced dewatering was applied, while the chlorine salt in MSWI FA was simultaneously removed using water in municipal sludge. The effects of different dosages and chemical components of MSWI FA on municipal sludge dewatering, and the removal effect of municipal sludge washing on Cl element were investigated. The results showed that the municipal sludge's specific resistance to filtration after co-treatment was significantly reduced, and more hydrophobic channels were formed in the vacuum suction filtration of the treated municipal sludge, conducive to efficient water removal. The moisture content of municipal sludge was reduced from 96.0% to 48.3%, and the moisture reduction rate increased from 17.7% to 32.1%. The chemical composition of MSWI FA could effectively promote the dewatering of municipal sludge, among which CaO was the best, followed by CaCl2 and NaCl, and KCl was the worst. Simultaneously, the municipal sludge showed a good effect on removing Cl from MSWI FA. The minimum Cl content in the mixture after Co-treatment is 1.5%. These results could provide a new way to dispose of MSWI FA and municipal sludge. Graphical abstract: Image 1 Highlights: A co-treatment system of MSWI FA and municipal sludge is proposed. MSWI FA can reduce the moisture content of municipal sludge to 48.3%. The effect on municipal sludge dewatering is: CaO > CaCl2 > NaCl > KCl. Applying municipal sludge to remove Cl from MSWI FA is feasible.