The velocity of flow in a sedimentation tank is to be kept ______ than the settling velocity.

The detention period of a plain sedimentation tank usually ranges from:

Jar test is conducted to determine:

The most commonly used coagulant in India is:

Which type of sedimentation tank is most commonly used?

Flocculation is a process of:

Which of the following gases is used for disinfection apart from chlorine?

In rapid sand filters, the rate of filtration is:

In slow sand filters, the rate of filtration is:

The allowable turbidity for water entering filtration units is:

In slow sand filter, cleaning is done by:

Break point chlorination is applied to ensure:

The main disadvantage of alum as coagulant is:

Find the detention time of a sedimentation tank of 20 m × 10 m × 3 m size with flow of 600 m³/hr.

What is the minimum residual chlorine desired after the chlorination process?

The settling velocity of spherical particles of diameter D is proportional to

The time period for which the water is stored in a sedimentation tank is called ____

Zero hardness in water is achieved by

Which coagulant is widely used for sewage treatment?

Backwashing is highly effective in case of

Which coagulant is widely used for sewage treatment?

A city has a population of 10000 with an average demand of 160 lpcd. Find the area of rapid sand filter if filtration rate is 4500 liters per hour per m².

In water treatment, when compared with rapid sand filter, slow sand filter produces

The process of passing water through beds of granular material is known as

Mixing of coagulant with water is carried out in:

Which of the following is not a unit operation of water treatment?

Chlorination is done for:

Average dose of chlorine used in water treatment is

Efficiency of sedimentation tank increases by the use of