Sedimentation Prelab

Batch Sedimentation Prelab

A. Effect of Initial Height on Sedimentation Characteristics 1) Prepare kaolin-in-water slurry of 5% concentration by weight in a preparation vessel. Stir well the slurry. 2) Fill the slurry in each sedimentation tube with different initial volumes (heights) – 400 cm, 600 cm and 800 cm. 3) Record the fall of the interface in each tube and the rise of the sludge interface at the base of the tube at 2-minute interval. 4) Collect data for 2 hours. 5) Empty and clean all the used sedimentation tubes.

B. Effect of Initial Concentration on Sedimentation Characteristics 1) Prepare equal volumes of kaolin-in-water slurry of 2.5%, 5% and 7.5% concentration by weight in three separate vessels. Stir well the slurry. See to it that the prepared volumes are enough to fill within 5 cm of the top of each sedimentation tube (i.e. more or less 90 cmhigh). 2) Fill each tube with the slurry starting with the most concentrated (7.5% concentration). The volume in each tube should be identical. 3) Record the fall of the interface in each tube and the rise of the sludge interface at the base of the tube at 2-minute interval. 4) Allow 24 hours to pass to get the final compaction readings. 5) Empty and clean all the used sedimentation tubes.