This paper aims the efficiency evaluation, in pilot scale, of a sludge blanket flocculator associated to a high rate settler using a cationic polymer as the primary coagulant. Three surface loading rates and different synthetic waters, with variable turbidities (from 3 to 100 NTU), were evaluated. The polymer dosages applied on the pilot scale were set up after jar tests. This technology showed a good performance for all rates and the results for all synthetic waters were similar with those obtained in the bench scale. This performance provides a clear feasibility of its use in actual scale for water supply systems, even to treat natural waters with low turbidity.
Sludge blanket sedimentation; high rate sedimentation; water treatment
