||Coagulation process is one of the important procedures of solid/liquid separation in water/wastewater treatment. There are many factors affects the success in coagulation among them, the dosage of coagulant is most difficult to control. The dosage of coagulant is usually determined by jar test or the experience of operators, which always leads to an overdose of coagulant. But overdosing causes high cost of coagulant, also high cost on sludge disposing. So far, existing equipments either high interference or high cost. There is necessary to develop a technique of low interference and low cost.|
In this research, to set up an optical image monitoring technique for coagulation, operate with image analysis observation and analysis the flocs in coagulation. Turbid water is made by kaolin particles dilute with tap water. Analyze the image which is captured by web camera, and compare analyzed data with the result of coagulation.
The results shows that the RGB values increased as the concentration of particles increased. Also, the RGB values decreased as the particles size increased when the mass concentration of particles remained the same. Therefore, as particles grew during coagulation, the RGB values changes correspondingly. Compare with the RGB values and coagulation, in successful coagulation there is a clear decreased trend of the RGB values and then jumped up and down about a value. But there is no trend in failed coagulation. Besides, from the RGB values and the situation of coagulation, the dosage of coagulant is less the dosage decided by jar test. On the results of fractal dimension, the flocs look similar and the fractal dimension of flocs were about 1.9.
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