Study of Rheology and Dewaterability of Sludge by Thermal and Conditioner Conditioning

• Main Authors: Jai-Shiang Hung, 洪嘉祥
• Other Authors: Cheng-Fang Lin
• Format: Others
• Language: zh-TW
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/98478296459874469543

碩士 === 國立臺灣大學 === 環境工程學研究所 === 88 === Due to the increase of sludge, treatments of disposal, reuse, incineration, landfill, volume reduction and the water content lowering of sludge are very important. On the premise of efficiency and economy, we show consideration for researches of conditioning, dewatering, and resource recovery of sludge. Thus, the research concentrated on the relationship between sludge dewaterability and characteristic of rheology in the dewatering process of sludge treatment. In the study, samples of sludge include PolyAluminum chloride (PAC) sludge from A water treatment plant, and biological sludge from B food-processing plant. To realize the conjuction of thermal / polymer (cationic polyacylamides; PC-325, chitosan) conditioning and characteristic of rheology of sludge is the first part in the study. Two parameters- Viscosity and Yield Stress are discussed. The second part in the study is the operation of sludge dewatering by laboratory centrifuge and belt press device. After sludge conditioning, the relationship between dewatering parameters and efficiency are discussed for evaluating the adapted parameters of rheology. It seems that parameter well adapted for evaluating the dewatering sludge is capillary suction time (CST). The minimum CST is corresponding to the best sludge dewaterability on centrifugation in the study. There is a very close relationship between sludge viscosity and yield stress for PC-325C conditioning of PAC sludge. These two parameters raise as increasing of PC-325C dosage. But, they are both minimum at 100 mg/l of chitosan with the best dewaterability. Sludge viscosity decreases as raising of temperature. Yield stress is minimum at 30 to 40℃ by thermal conditioning. For sludge conditioning of food-processing sludge, both of sludge viscosity and yield stress are maximum at 15mg/l of PC-325C, and they are minimum at 60 mg/l of chitosan. The best dewaterability appears at 50℃. There is a very close relationship among CST, viscosity, and yield stress for the two kinds of sludge by modifying the solids content.