4aerobic digesters (water depth = 15 ft) received waste from an mbr treatment plant. given conditions: q = 0.5 m. g.d., bod = 180 mg/l , soluble bod = 100 mg/l, t. s.s. = 200 mg/l, v. s.s. = 160 mg/l, mlss = 7000 mg/l, srt= 28 days, y= 0.8 and kd=0.04 (d-1 ). the target effluent soluble bod is zero. calculate the aeration basin volume, waste sludge, and volume of each aerobic digester required to meet class b requirements.

Assuming compressible flow of air and that the measurements are done at flagstaff a pitot static tube that gives the difference of total and static pressure measures 0.35 m of mercury. what is the velocity of air? assume the temperature to be 300k. (submit your excel or matlab calculation sheet)

The flow rate of air through a through a pipe is 0.02 m5/s. a pitot static tube is placed in the flow. the radius of the pitot static tube is 1 mm. assuming the flow to be steady and the air to be at 300k, calculate the difference in total and static pressure if the diameter of the pipe is: (a) d 0.1 m d 0.05 m (c) d 0.01 m

Athin walled concentric tube exchanger is used to cool engine oil from 160°c to 60°c with water that is available at 25°c acting as a coolant. the oil and water flow rates are each at 2 kg/s, and the diameter of the inner tube is 0.5 m and the corresponding value of the overall heat transfer coefficient is 250 w/m2. oc. how long must the heat exchanger be to accomplish the desired cooling? cpwater=4.187 kj/kg-candcpengine el=2.035 kj/kg·°c, oil . 120]