| Summary: | 碩士 === 淡江大學 === 化學工程與材料工程學系碩士班 === 95 === This study uses the software FLUENT(used for computational fluid dynamics) to simulate flocculation (reaction) clarifier blanket inside Bansin water treatment plant. We first establish the geometric structure and mesh of the clarifier blanket, then provide feed velocity, concentration, impeller rotation, and operation conditions for the sludge blanket. Then we use the Eulerian multiphased model to calculate and analyze the flow field inside the water treatment plant. Next we explore flow field alterations resulting from changes in these five following variables: impeller rotational velocity, feed concentration, sludge blanket concentration and height, clarifier blanket structure, and temperature. Using the above calculations and analysis, we hope to obtain better water quality.
This study shows that high impeller rotational velocity causes the sludge blanket structure on the bottom of the tank to float and turn easily. With varying feed concentration, the only significant difference is in the initial effluent solid mass flux; Changes become less observable as time goes on. The height and concentration of the sludge blanket both correspond directly to the solid mass flux. Regarding changes in the geometric structure, we find that the smaller the angle of the reaction well, the longer the solid particles stay in the reaction well. Under the condition of constant daily water-processing quantity, larger feed diameter leads to better water quality. Lastly, temperature increases flow dynamic circulation. Thus, high temperature during the summer may lead to difficulties in processing water quantity.
|
|---|
