Modification
of
Sedimentation
Tank - Since the sedimentation efficiency depends on the surface area and not on the depth, installation of an extra bottom in the settling zone will increase sedimentation efficiency. This set up can further be improved by using more trays.
However this modification has a drawback in that the removal of sludge deposits will be difficult as the space between the trays are very small. This problem can be overcome by using jet washing or by setting self-cleaning plates.
In the latter case the plates are set steeply at an angle of 40° to 60° to the horizontal. Such installations are called tilted plate settling tanks. Instead of tilted plates closed packed PVC pipes can also be used.
