Journal
SCIENCE OF THE TOTAL ENVIRONMENT
Volume 842, Issue -, Pages -Publisher
ELSEVIER
DOI: 10.1016/j.scitotenv.2022.156874
Keywords
Sewage sludge; Dissolved ozone flotation; Sludge thickening; Extracellular polymers; Physicochemical properties
Categories
Funding
- National Key Research and Development Project [2020YFC1908704]
- China Three Gorges Corporation [202003166]
- National Natural Science Foundation of China [52000139]
Ask authors/readers for more resources
This study investigated the thickening performance of sludge using dissolved ozone flotation (DOF). The results showed that DOF can change the surface properties of sludge, destroy the floc structure, release organic matter, and increase moisture fluidity. The key influencing factors were found to be surface properties, protein structure, and moisture distribution.
Sludge thickening in sewage treatment plants is an essential step to reduce the sewage sludge volume and provide space for collaborative anaerobic digestion of sludge and other urban organic wastes. Dissolved ozone flotation (DOF) is a novel choice worthy of application in the field of sludge thickening. In order to investigate the effect of DOF thickening, the total solid content (TS %) was used to characterize the thickening performance under different O-3 dosage. The optimal condition was determined to be polyacrylamide (PAM) dosage = 3 %o TS, air floatation time = 2 h and O-3 dosage = 12 mg/g TS, under which the TS % of raw-sewage sludge (RS) increased from 0.33 +/- 0.01 % to 8.03 +/- 0.06 %. In this study, the relationship between the sludge thickening performance, physicochemical properties, and the changes of organic matter (content, structure and molecular weight) in extracellular polymers (EPS) was systematically clarified. The results indicated that the DOF couple with PAM could change the sludge surface properties, destroy the sludge floc structure, release intracellular organic matter, and increase moisture fluidity. The surface hydrophilicity/hydrophobicity, protein (PN) secondary structure and moisture distribution were mainly responsible for sludge thickening performance. Moreover, the change of TS % during the DOF thickening process was mainly caused by the variations of the organic matter content in EMPS layer. The identification of key influencing factors was conducive to the further regulation and upgrading of the novel application for enhanced sludge thickening in sewage treatment plants.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available