Example 9.18. A rectangular sedimentation tank following coagulation- flocculation is to treat a flow of 3000 m³ / day with a detention time of 6 hours. It is to be hand cleaned of sludge at 6 week intervals. The suspended solids concentration of the water is reduced from 250 mg/L to 5 mg/L by coagulation- flocculation. The settled sludge includes 40 mg/L (based on water flow) of metallic precipitate and has a moisture content of 85% and specific gravity of 1.24. Determine the volume of sludge produced between cleanings and the basic dimensions of the tank if the water depth just before cleaning is 3 m and its length is twice its width. (GATE 1995)

Example 9.18. A rectangular sedimentation tank following coagulation- flocculation is to treat a flow of 3000 m³ / day with a detention time of 6 hours. It is to be hand cleaned of sludge at 6 week intervals. The suspended solids concentration of the water is reduced from 250 mg/L to 5 mg/L by coagulation- flocculation. The settled sludge includes 40 mg/L (based on water flow) of metallic precipitate and has a moisture content of 85% and specific gravity of 1.24. Determine the volume of sludge produced between cleanings and the basic dimensions of the tank if the water depth just before cleaning is 3 m and its length is twice its width. (GATE 1995)

Fundamentals of Geotechnical Engineering (MindTap Course List)

5th Edition

ISBN:9781305635180

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter7: Seepage

Section: Chapter Questions

Problem 7.6P

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