Which of the following cannot be the velocity of flow in the horizontal flow sedimentation tank?
Explanation: The maximum value of the velocity of flow is 30cm/min, so it cannot be 39cm/min.
The deviation from the ideal flow of wastewater in the sedimentation tank causes
Explanation: The deviation from the ideal flow of wastewater in the sedimentation tank causes short circuiting. It results in variation in the detention period in the top and bottom layer of wastewater in the tank.
The overflow rate for a plain sedimentation tank is ______ litre/day/metre2.
Explanation: The overflow rate for a plain sedimentation tank lies between 12000-18000 litre/day/metre2.
The detention period for a sedimentation tank where coagulation takes place is
Explanation: The detention period for a sedimentation tank without coagulation is 4 hours, whereas with coagulation is 2 – 2.5 hours.
The test for finding the optimum coagulant dose in water is
Explanation: Jar test is used to find the optimum coagulant concentration that is required to cause coagulation in water so that the settling of suspended impurities takes place.