5-29. The following data were obtained from a test program designed to
evaluate a new diffused-air aeration system. Using these data, determine the
value of KLa at 20 and the equilibrium dissolved-oxygen concentration in the
test tank. The test program wa
7-7. An aerobic complete-mix reactor (no recycle) with a volume of 1000L receives a 500 L/d
wastewater flow and has an effluent soluble COD concentration of 10 mg/L. For one of the wastewater
with the characteristic given below, determine (a) the value fo
5-1. A vertical bar screen is constructed of 20-mm diameter bars that have a clear spacing of 25mm.
Determine the headloss and velocity through a clean screen when the channel approach velocity is 1.0
m/s. If the screen is inclined
Peak factor (The ratio of the peak flowrate to the average flowrate)
Sustained peaking factor , PF=
long term average flowrate
Peaking factors are applied most frequently to determine the peak hourly flowrate.
Mass Loading Rates (The product
5-22. Design a circular radial-flow sedimentation tank for a town with a projected population of
45,000. Assume that the wastewater flowrate is 400 L/capita d. Design for 2 h detention at the
average flow. Determine the tank depth and diameter to produce
8-20. An activated sludge system is to be designed for nitrification to achieve an
effluent NH4-N concentration of 0.5 mg/L at a reactor DO concentration of 2.0 mg/L
and 10C temperature. The peak/average TKN load is 1.8. Determine the design SRT.