Design of Thickeners

Abstract

This chapter presents different theories of thickener design. These theories have been applied to the solution of the same problem, wherever applicable, to reveal the relative outcome of the solutions for comparison.

Notations

C ₀ :

Feed concentration of solids

h ₀ :

Sludge column height

C ₂ :

Concentration of solids at the interface

h ₂ :

Interface height

${h}_2^{\prime }$ :

Intersected height on interface height axis of interface height versus time curve by the tangent drawn at interface height h₂ of the curve

$\overline{u_2}$ :

Interface settling rate

C _u :

Concentration of underflowing sludge

t _u :

Settling time to thicken the sludge to underflow concentration C_u

${C}_{\infty }$ :

Ultimate concentration of settled sludge

${t}_{\infty }$ :

Least time to thicken the sludge to its ultimate concentration

${C}_c$ :

Concentration of sludge at compression point

t _c :

Time to reach the compression point

$\overline{u_H}$ :

Hindered settling velocity

h _u :

Interface height at underflow concentration C _u

F _T :

Total flux flow

F _sb :

Batch sludge Flux

F _su :

Underflow sludge flux

F _m :

Minimum total flux