$8-24.$ The Jambalaya shrimp processing plant generates $0\mathrm{.}012\frac{m^3}{s}$ of wastewater each day. The wastewater is treated in an activated sludge plant. The average $BO{D}_5$ of the raw wastewater before primary settling is $1,400m\frac{g}{L}.$ The aeration tank has effective liquid dimensions of $8\mathrm{.}0$ m wide by $8\mathrm{.}0$ m long by $5\mathrm{.}0$ m deep. The plant operating parameters are as follows:

Soluble $BO{D}_5$ after primary settling $=966m\frac{g}{L}$

$MLVSS=2,000m\frac{g}{L}$

$MLSS=1\mathrm{.}25(MLVSS)$

Settled sludge volume after $30$min$=225\mathrm{.}0m\frac{L}{L}$

Aeration tank liquid temperature $=15C$

$8-27.$ Using the following assumptions, determine the solids retention time, the cell wastage flow rate, and the return sludge flow rate for the Jambalaya shrimp processing plant WWTP $($Problem $8-24).$ Assume:

Allowable $BO{D}_5$ in effluent $=25\mathrm{.}0m\frac{g}{L}$

Suspended solids in effluent $=30\mathrm{.}0m\frac{g}{L}$

Wastage is from the return sludge line

Yield coefficient $=0\mathrm{.}50mg$ VSS $\frac{?}{mgBO{D}_5}$ removed

Decay rate of microorganisms $=0\mathrm{.}075d^{-1}$

Inert fraction of suspended solids $=30\mathrm{.}0\%$

$8-30.$ The single secondary settling tank at the Jambalaya shrimp processing WWTP $($Problem $8-24)$ is $5\mathrm{.}0$ m in diameter and $2\mathrm{.}5$ m deep at the side wall. The effluent weir is a single launder set on the tank wall. Evaluate the overflow rate, depth, solids loading, and weir length for conformance to standard practice.