Problem $3$

Design a circular primary settling tank, if the average flow rate $5000m^3/$day with a peak factor

of $2\mathrm{.}5.$ The overflow rate is $35\frac{m^3}{m^2}.$day

Design Criteria Rectangular Sedimentation Tank

Length

$30$m

Width

$10$m$(13$m max$)$

L:W

$<mn>4</mn>$:$1(2$:$1$ generally$)$

Bottom slope

$1-2\%($w$/$o scrapers$)$

Design Criteria circular Sedimentation

Tank

Dia

$30$m$($max$)$

Depth

$3-5$m

Bottom slope

$8\%($hopper bottom $+$ scrapers$)$