Test: Various Unit Operations - Civil Engineering (CE) MCQ

Explanation: In Gas transfer, gases are released or absorbed in water by exposing the water through aeration under normal, increased or reduced pressure.

Explanation: There are 4 types of aerators namely Gravity aerators, Spray aerators, Diffusers and Mechanical aerators.

Explanation: Chemical coagulation is used to remove colloidal particles by the use of coagulants which increase the particle size and they settle down.

Explanation: Chemical precipitation removes the dissolved substance from water through ion transfer where precipitation of dissolved impurities takes place.

Explanation: In solute stabilization, water is stabilized by chlorination or liming so that objectionable solutes are converted into unobjectionable form.

Explanation: By the process of chlorination, water gets stabilized by the conversion of hydrogen sulfide into sulfate.

Explanation: When water passes through limestone, carbon dioxide in excess get converted into soluble bicarbonate.

Explanation: By Re-carbonation of water softened by excess lime treatment, excess lime is converted into bicarbonate.

Explanation: By addition of chlorine dioxide to water, odour producing substances are oxidized.

Explanation: During solids transfer, solids are removed from water by straining, sedimentation, flotation and filtration.

Explanation: Organic contaminants are removed from the water by the attraction and accumulation of one substance on the surface of another.