Problem 6.4 A sound level reading of 132 dB was taken near a construction site where some chippers were being used. When
Posted: Wed Apr 27, 2022 2:50 pm
- Problem 6 4 A Sound Level Reading Of 132 Db Was Taken Near A Construction Site Where Some Chippers Were Being Used When 1 (15.05 KiB) Viewed 54 times
- Problem 6 4 A Sound Level Reading Of 132 Db Was Taken Near A Construction Site Where Some Chippers Were Being Used When 2 (41.87 KiB) Viewed 54 times
Problem 6.1 To cater for the long-term development need in Hong Kong, Hung Shui Kiu is identified as a suitable new development area to address the housing demand. The HKSAR Government plans to house an additional 186,000 people in Hung Shui Kiu. Assuming a new sewage treatment work will be designed to treat the sewage discharged by the additional residents. 0.3 ml of sewage per capita per day will be sent to the sewage treatment work. A rectangular primary sedimentation tank is designed with an effective length of 50.0 m and width of 40,0 m. The height of the tank is 4.0 m. Estimate the hydraulic retention time (HRT) and the overflow rate. (2 marks) Problem 6.2 Given a flow rate of 7000 m d and an overflow rate of 40 m d m´), calculate the following design parameters of a proposed circular primary sedimentation tank: (i) Height of the sedimentation tank (assuming a criterion of diamter/height ratio of 3. take t-3.14 in the calculation). (2 marks) (ii) Hydraulic retention time (HRT) of the sedimantation tank. (1 mark)