A novel sewage sludge biochar and ferrate synergetic conditioning for enhancing sludge dewaterability. (December 2019)

• Record Type: Journal Article
• Authors: Wu, Jiahuan; Lu, Tao; Bi, Jingwang; Yuan, Haoran; Chen, Yong
• Is Part Of: Chemosphere. Volume 237(2019)
• Publication Date: 2019-12
• Subjects: Biochar -- Potassium ferrate -- Skeleton builder -- Dewaterability -- Waste activated sludge; WAS waste activated sludge -- H height of settlement interface over time -- CST capillary suction time -- DDCOD disintegration degree -- SCOD soluble chemical oxygen demand; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2019.07.070
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: A great prospect of sewage sludge self-recycling as a conditioner supports the research. A synergetic conditioning effect and mechanism were reflected after the synergistic conditioning experiment, and the corresponding separated experiment of biochar, K2 FeO4 or acid treatment on WAS. All of the biochar, K2 FeO4 and acid treatment could reduce the water content of sludge cake. Biochar had good effect on WAS settleability, although the influence of the biochar dosage was weak. Similar to K2 FeO4, acid treatment also could reinforce the disintegration degree effectively, but it deteriorated the filter property of WAS. In the situation of synergistic condition, owing to the strong oxidation of K2 FeO4, most of the sludge flocs was disintegrated, thus the settleability and filter property of WAS were still bad, even the biochar worked as a skeleton builder. It is encouraging to find that, even without acid treatment, there is a great decline of water content of sludge cake in the situation of synergistic condition. Highlights: K2 FeO4 and sewage sludge–derived biochar as composite conditioning agent is feasible and effective. The mechanism of the improved dewater was illustrated. Self-recycling of sewage sludge as skeleton builder is a novel approach for utilization of sewage sludge.