Influence of energy input and energy input time during flocculation on the filterability of generated flocs

Abstract EN

This research aims to study the influence of energy input and energy input time during the flocculation stage on the ability of forming the filterability flocs through practical experiments done by using the floc filtration test apparatus (coagulation-flocculation-filtration) for different turbidities (C0) NTU (50, , and 200) by using local alum as a coagulant substance.

In order to achieve the requirements of the coagulation mechanism of colloids suspension by means of absorption and charge neutralization by using (G) for the (G rapid mixer ≥ 730 sec-1) and for coagulation time (Tc =3 min).

It is decided to use the variable G (for the flocculation stage) ranging (15-100 sec-1) and flocculation time ranging from (5-60 min) The turbidity of the effluent was measured so as to get the efficiency of removing turbidity for each test and compare the results obtained from every experiment (the removal efficiency and the length of the filtration period) to examine the change occurring in these results with different factors influencing the flocculation operation (energy input time, and energy input), (velocity gradient).

We have concluded a general diagram showing the allowed limits of G (velocity gradient), Tf (flocculation time) and GT (Camp number), which produce the best removing efficiency by using floc filtration test apparatus, for all the studies initial turbidity.

The value of G range between (40-50)sec-1, while the value of Tf range between (15-25)min and GT values were between (36000-75000) is provided.