Clarification of turbid water with the use of Praestol 650 flocculant

Summary

The efficiency of the individual use of the cationic flocculant Praestol 650 for the purification of turbid water is considered, depending on the turbidity of the source water and the conditions of flocculation. It is shown that the priority parameters that determine the effectiveness of the individual use of the cationic flocculant Praestol 650 for the purification of turbid natural water are the intensity and duration of mixing in the flocculation chamber. With a duration of at least 20 min and an average gradient of mixing rate G = 340 s-1, the efficiency of turbidity reduction is 96% (final turbidity being 7 mg/l). A 96% efficiency of the non-ionic flocculant with a molecular weight of 5–7 million was determined in a suboptimal flocculation mode with a mixing period of 5 min and G = 65 s-1.

Key words

settling , turbidity , flocculation , cationic flocculant , water clarification , mixing rate gradient

Removing fine clay impurities from natural water

Summary

The effect of the clay impurities (loams, clays, bentonites, kaolin) origin that determines the turbidity of natural water, on the kinetics of their sedimentation was studied. The percentage of clay impurities with a hydraulic size of 0.11 mm/s was determined. The effectiveness of the independent use of Praestol 650 cationic flocculant for removing clay impurities of various origin from turbid water is considered. It was established that the efficiency of natural water purification depended on the mineral composition and disperse characteristics of clay particles and could be increased for kaolinite-containing clay impurities from 69 to 91% by optimizing the flocculation parameters. It was shown that the optimal dose of Praestol 650 flocculant did not depend on the origin and disperse characteristics of clay particles and was 0.2 mg/l at an initial water turbidity of 107–187 mg/l. The possible use of the kinetic and flocculation characteristics of clay impurities in natural water to identify their mineral composition is considered.

Key words

cleansing , settling , turbidity , flocculation , hydraulic size , natural water , cationic flocculant , mixing rate gradient , clay impurities