Affiliation:
1. Xi'an University of Architecture and Technology
2. Xi’an Urban Drainage Monitoring Station
Abstract
Based on that floc structure is an important factor that influencing the coagulation effect and the post-treatment load, the effect of PAM on floc structure of typical system is analyzed and evaluated in this paper. The results show that PAM has a notable influence on floc morphological structure characteristics. For inorganic turbid system, the fractal dimension and diameter of kaolin flocs adding PAM are bigger than that formed by adding aluminum sulfate merely, and the shear-resistant ability of flocs is stronger. With regard to dissolved organic system, adding PAM under two typical pH conditions, the floc morphological characteristic has the same variation with that in inorganic turbid system. PAM could improve the floc morphological structure. However, the improving effect will be relatively weaker under slightly acidic condition, which indicates that the chemical effect of PAM is restrained under this condition. While for the coexisting system, PAM shows an obvious improvement on floc structure under two pH conditions, the floc is compact, bigger and with a higher strength. The chemical effect of PAM is not restrained under slightly acidic condition, which may owe to the interaction between PAM and inorganic suspended materials and dissolved organics in coexisting system.
Publisher
Trans Tech Publications, Ltd.
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