water treatment

The settling velocity of inorganic particles in the sedimentation tank of a water treatment plant is governed by

The maximum demand at a water purification plant has been estimated as 12 million litres per day. For the raw supplies, a rectangular sedimentation tank is to be designed with mech...

Fecal Coliform (FC) concentration in river water was measured as 10780 cfu/100 ml. The FC concentration after the conventional water treatment, but before chlorination, was measure...

The Surface Overflow Rate (SOR) in a rectangular sedimentation tank is 45 m³/m²/d. Minimum diameters of spherical inorganic and organic particles expected to be completely removed...

Aeration is employed as a treatment option for the removal of several pollutants from contaminated water. Identify the pollutant(s), where aeration is employed as a part of their r...

Free residual chlorine concentration in water was measured to be 2 mg/l (as Cl2). The pH of water is 8.5. By using the chemical equation given below, the HOCl concentration (in μmo...

Aeration is employed as a treatment option for the removal of several pollutants from contaminated water. Identify the pollutant(s), where aeration is employed as a part of their r...

Fecal Coliform (FC) concentration in river water was measured as 10780 cfu/100 ml. The FC concentration after the conventional water treatment, but before chlorination, was measure...

A hypothetical multimedia filter, consisting of anthracite particles (specific gravity: 1.50), silica sand (specific gravity: 2.60), and ilmenite sand (specific gravity: 4.20), is...

A water treatment plant treats 25 MLD water with a natural alkalinity of 4.0 mg/L (as CaCO3). It is estimated that, during coagulation of this water, 450 kg/day of calcium bicarbon...

A water treatment plant treats 25 MLD water with a natural alkalinity of 4.0 mg/L (as CaCO 3 ). It is estimated that, during the coagulation of this water, 450 kg/day of calcium bi...

Which of the following is/are NOT active disinfectant(s) in water treatment?

In the following table, identify the correct set of associations between the entries in Column-1 and Column-2. Column-1 P: Reverse Osmosis Q: Trickling Filter R: Coagulation S: Ads...

In the context of water and wastewater treatments, the correct statements are:

A flocculator tank has a volume of 2800 m³. The temperature of water in the tank is 15°C, and the average velocity gradient maintained in the tank is 100/s. The temperature of wate...

In the following table, identify the correct set of associations between the entries in Column - 1 and Column-2. Column-1 Column-2 P: Reverse Osmosis III: Concentration Polarizatio...

Which of the following is/are NOT active disinfectant(s) in water treatment?

Which of the following process(es) can be used for conversion of salt water into fresh water?

A water treatment plant has a sedimentation basin of depth 3 m, width 5 m, and length 40 m. The water inflow rate is 500 m³/h. The removal fraction of particles having a settling v...

Which of the following processes can be used for conversion of salt water into fresh water?

A water treatment plant has a sedimentation basin of depth 3 m, width 5 m, and length 40 m. The water inflow rate is 500 m 3 /h. The removal fraction of particles having a settling...

A water filtration unit is made of uniform-size sand particles of 0.4 mm diameter with a shape factor of 0.84 and specific gravity of 2.55. The depth of the filter bed is 0.70 m an...

During chlorination process, aqueous (aq) chlorine reacts rapidly with water to form Cl-, HOCl, and H+ as shown below Cl₂ (aq) + H₂O ⇌ HOCl + Cl⁻ + H⁺ The most active disinfectant...

A water supply scheme transports 10 MLD (Million Litres per Day) water through a 450 mm diameter pipeline for a distance of 2.5 km. A chlorine dose of 3.50 mg/litre is applied at t...

A completely mixed dilute suspension of sand particles having diameters 0.25, 0.35, 0.40, 0.45 and 0.50 mm are filled in a transparent glass column of diameter 10 cm and height 2.5...

Chlorine is used as the disinfectant in a municipal water treatment plant. It achieves 50 percent of disinfection efficiency measured in terms of killing the indicator microorganis...

Sedimentation basin in a water treatment plant is designed for a flow rate of 0.2 m³/s. The basin is rectangular with a length of 32 m, width of 8 m, and depth of 4 m. Assume that...

A water treatment plant treats 6000 m³ of water per day. As a part of the treatment process, discrete particles are required to be settled in a clarifier. A column test indicates t...

A 0.80 m deep bed of sand filter (length 4 m and width 3 m) is made of uniform particles (diameter = 0.40 mm, specific gravity = 2.65, shape factor = 0.85) with bed porosity of 0.4...

A rapid sand filter comprising a number of filter beds is required to produce 99 MLD of potable water. Consider water loss during backwashing as 5%, rate of filtration as 6.0 m/h a...

A flocculation tank contains 1800 m³ of water, which is mixed using paddles at an average velocity gradient G of 100/s. The water temperature and the corresponding dynamic viscosit...

At a small water treatment plant which has 4 filters, the rates of filtration and backwashing are 200 m³/d/m² and 1000 m³/d/m², respectively. Backwashing is done for 15 min per day...