Exercise n° 1 The drinking water source for a city is a reservoir and the water is treated by conventional processes. The nt is 160 ft. In order to supply water surface elevation in the clear well at the end of the treatment pla adequate pressure for the municipality, the hydraulic grade line (HGL) of the water system must be at elevation 330 ft. Treated water is pumped through 2 miles of 16 inch diameter ductile iron pipe (CHW = 120) to the water distribution system. If the ratio of maximum day demand to average day demand is 1.5, what is the required pump power (in horsepower) to supply Qmax X day in the future (20 years from now)?Exercise n° 2 A complete mix activated sludge process is to be used for biological treatment. Assume average flow conditions and the primary treatment performance as in part d) above. Assume the following for the activated sludge process:•••••••••Plant effluent BOD5 of 12 mg/L Biomass yield (Y) of 0.54 kg biomass / kg BOD Endogenous decay rate (IQ) = 0.05 day’ Solids Retention Time (Ac) = 8 days MLVSS concentration in the aeration tank (X) of 2700 mg/L Waste and recycle solids concentration (XR) of 12,000 mg/L Make calculations based on a single train, i.e., total plant flow for the following:••••••••••••Determine the aeration tank volume in cubic meters. Determine the design hydraulic detention time, in hours. Determine the mass (dry) and volumetric rates of secondary sludge wasted (kg/day, m3/day). Determine the sludge recycle (return) flow rate in m3/day and the recycle ratio. Determine the food to microorganism ratio. Exercise re’ 3 You have been selected to design a secondary wastewater treatment plant (WWTP) for a city of 15,000 people which has some industry that discharges wastewater to the municipal sewer system. The average daily wastewater flow is 2.1 MGD and the raw sewage entering the WWTP has an average BOD5 of 240 mg/L and average suspended solids of 260 mg/L.••••••If the average domestic per capita sewage flow is I. gpcd, what is the average flow of the industrial wastewater (in IVIGD)? If the average BOD5 load from the domestic sewage i BOD5 loadin is 0.18 lbsicapita-day, what is the average daily g (in lbsiday) from the industrial wastewater? Wh BOD5 loadin? at is the population equivalent to this g
