Answer Happy

(e) What is the major goal of secondary wastewater treatment? 1) Removing nutrients ii) Removing large particles iii) Removing organics iv) Disinfection (1) Which is using suspended growth of microbes for pollutant removal in wastewater? i) Trickling filter ii) RBC iii) Activated sludge system iv) Membrane (9) The relationship between substrate and growth rate of aerobes can be explained by i) Monod equation ii) Sedimentation iii) MLE iv) Laminar flow (h) What is the time for wastewater to stay in the reactor? i) HRT ii) Mean cell residence time iii) Contact time iv) t12 (i) In activated sludge system, SRT is governed by i) HRT ii) Sludge wastage iii) Aeration iv) ii) High yield iv) Microbes are starving C) If F/M is high, then i) Longer SRT iii) Better effluent quality (k) During biological P removal, PAOs i) release S in anaerobic condition iii) release P in aerobic condition ii) accumulate P in anaerobic condition iv) accumulate P in aerobic condition () To remove N in wastewater by air-stripping, pH of wastewater should be i) Neutral (pH 7) ii) Acidic ( < pH 5) iii) Alkali (> pH 10) (m) During biological N removal, what happens in the anoxic zone? 1) NOx generation ii) High in NOX iii) Converting NO, to N2 iv) No additional organic addition