Page -5 gm of flocculent required per mof waste. -Flocculent prepared as 10% weight solution. -Specific gravity of coagulant solution = 1.0. Determine the: i) required recycle flow in mºd, [4 marks ii) required surface area in m?, [2 marks] iii) volumetric rate of total sludge generated m®/d, [8 marks] iv) volumetric rate of coagulant solution fed to the system in m'/d and [2 marks] v) required gauge pressure in kPa if the flotation clarifier is working without recycle. [4 marks]
120 marks uestion 3: 170563 A flotation treatment system clarifier is developed to treat 3786 m/d of a waste containing 360 mg/L of suspended solids to an effluent of 18 mg/L. The following applicable design criteria were established by laboratory studies: Surface overflow loading rate: 40.7 m3/(mº.d). Final solid sludge concentrate : 1 wt%. Air to solid ratio : 0.03 mg/mg. Air soluibility efficiency (f) : 0.8. Temperature: 68 °F. Air soluibility: 24.4 mg/L. Recycle gauge pressure: 482.4 kPa. To achieve 18 mg/L effluent some flocculent aid may have to be added to the flotation influent, provisions should be made according to the following criteria: