WASTE WATER TREATMENT, Physical unit operation, Chemical unit operation, Biological unit operation, Preliminary Treatment, Screening, Comminution, Flotation, Grit Removal, Preliminary treatment, Primary treatment, Secondary treatment, Tertiary/advanced treatment, Biological treatment Processes (Aerobic Process), Activated Sludge, Oxidation ditch, Trickling filter, Biofilter (Biotower), Rotating biological contactor, Facultative Stabilization ponds, Aerated lagoons, Return Activated Sludge (R.A.S), Waste Activated Sludge (W.A.S),

1. WASTE WATER TREATMENT MAJID MOHIUDDIN

4. Raw waste water Screening Chamber Grit Primary setting tank Aeration Tank Secondary Settling Tank Effluent Sludge thickener Anaerobic digestion Sludge thickener Sludge Disposal Primary sludge Sludge recycling (30-40%) Activated sludge (Secondary sludge) Grit Chamber

8. Primary Sedimentation tanks (or) Clarifiers (or) rectangular basins 3 – 5 m deep Hydraulic retention time 2 and 3 hrs. Radial flow pattern Scraper truss arm Rotating arm Scraper blades Sludge Hopper Primary Sludge Clean surface water Weir 30% BOD, 50-70% Total Suspended Solids and 65% of the oil and grease are removed during primary treatment. And some organic and phosphorus also. Primary effluent

13. Activated Sludge Process

40. Water containing complex organic matter (Carbohydrates, Proteins, Lipids) Hydrolysis (Extracellular enzymes) Simple Organic Compounds (Sugar, amino acids, peptides) H 2 , CO 2 , Organic acids, Alcohols H 2 , CO 2, , Acetic acid Methane, CO 2 Methanogenesis Acetogenesis Acidogenesis

50. Thank you MAJID MOHIUDDIN