For an activated sludge basin with a flow rate of 500 L/s if the influent BOD5 = 100 mg/L, the MLVSS = 3000 mg/L and the volume of the aeration basin = 766100 gallons Find the F/M ratio If the WAS  X= 10000 mg/L, find the WAS flowrate (m3/d)

2. The average wastewater flow from a community of 20,000 is 125 gpcd. The 5 day, 20 deg C BOD is 250 mg/L. The suspended solids content is 300 mg/L. A final plant effluent of 50 mg/L of BOD is to be achieved through the use of two sets of identical settling tanks and trickling filters operating in parallel. The settling tanks are to be designed to a standard of 1000 gpd/^2. The trickling filters are to be 6^ deep and operated at an organic loading of 55 lbm/1000^3 d. There is no recirculalon. (1) What settling tank surface area is required? In ft^2 (2) What settling tank diameter is required? In ft (3) Estimate the BOD removal in the settling tanks? In percent % (4) What is the trickling filter diameter? In ft domeved Ward

The influent suspended solids concentration to a primary settling (clarifier) tank is 300 mg/L. The average flow rate is 0.037 m3/s. If the suspended solids removal efficiency is 65 percent, how many kilograms of suspended solids are removed in the primary settling tank each day?

Two circular clarifiers operated in parallel service a single stage bio-tower system (plastic media) that receives municipal wastewater at an average flow (Qaverage) of 2000 m³/d, with BOD5 = 200 mg/L. The internal flow recirculation ratio is 2.4. The maximum overflow rate for the clarifiers is 1.8 m³/m²-hr. The design procedures require that the sizing of the clarifiers be based on "PEAK" flow which is twice the average flow (Qpeak = 2 × Qaverage), and media depth in the biotower is 3.0 m. Determine: (a) The overall BOD5 removal. (b) the surface area and the diameter of each clarifier. (k = 0.06 min¹; n = 0.5),