CIVE 450 Problems Page 1, Spring 2014

CIVE 450 Problems (WATER TREATMENT) A. A 6-cm throat Venturi meter is installed in an 18-cm diameter horizontal water pipe. The reading of the differential manometer is 18.6 cm of mercury column (sp gr= = What is the flow in the pipe. To calculate Cy use the following Ca = V/ [(AV/A2) - 1)°° 2. Determine the discharge ofa free flow 2-ft Parshall flume with gage reading (h) =1.55 ft. Compare the results with results obtained using the following formula: Q =4W h'? w?.026 3. A water bar screen is constructed with 10 mm (0.375 in) wide bars spaced 5.8 cm (2.25 in) apart center to center. If the approach velocity in the channel is 0.6 m/sec (2 ft/sec), what is the velocity through the screen openings. 4. Estimate the terminal settling velocity in water at a temperature of 15°C of spherical silicon particles with specific gravity 2.4 and average diameter of (a) 0.05 mm and (b) 1.0 mm. 5. The settling velocity of alum floc is approximately 0.00043 m/sec in water at 10°C. Calculate the equivalent overflow rate in m/d. What is the minimum detention time in hours to settle out alum floc in an ideal basin with a depth of 3.7 meters. Calculate the diameter and depth of a circular sedimentation basin for a design flow of 3800 m?/d based on an overflow rate of 0.00024 m/s and a detention time sedimentation tanks for a 35,000 m3/d water treatment plant using the ing design criteria: flow velocity (check for scoure velocity) table is 75m3/d/m)