The Investigation on the Ability of Particle Removal from High-turbidity Reservoir Water

• Main Authors: Chau-Cheng Song, 宋朝正
• Other Authors: Po-Ching Lee
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/25437723650294897829

碩士 === 淡江大學 === 水資源及環境工程學系碩士班 === 94 === Removal of turbidity from raw water is critical to the water treatment plant because of large amount of particles suspended in the water especially after heavy rain showers. It is difficult to remove micrometer sized particles (eg. D(50) = 6.5 μm) due to longer retention is needed for settlement. Our task is to investigate the ability of particle removal from high turbidity reservoir water, and the conventional settlement process, coagulation and electro-aggregation processes were also compared. The results of the experiments reveal that high turbidity raw water samples (500, 1500, 3000 NTU) can be treated by coagulation at pH 7 at the PAC dosage of 50, 100, 150 mg/l, respectively, and the results come out the treated water of 3, 3.5, 3.2 NTU. The particle removal ability by electro-aggregation process, using aluminum plate as electrodes are significant. The turbidities of water samples (500, 1500, 3000 NTU) decreased to 3.8, 3.8, 4.0 NTU, respectively, under the conditions as followed: 128 second hydraulic retention time; 150~200 V voltage; and 0.4~2.2A electric current. The conductivity of the raw water dropped down at least 30% during electro-aggregation process. The pilot study should be performed in the near future before full scale of application due to insufficient information is available. The time it took for the conventional coagulation is fifteen times longer than that of electro-aggregation. Comparing these two processes, the electro-aggregation may benefit from its smaller size and fast treatment in treating high turbidity reservoir water. Keyword: electro-aggregation process, electrochemistry, high turbidity, particle removal, coagulation