Water Purification Process
Abstraction: Abstraction involves pumping and transportation of raw water, a process with high rate of electrical energy consumption. It occurs at the intake.
Screening: Is defined as the process whereby relatively large and suspended debris is removed from the water before it enters the plant.
Aeration: Aeration (Air Stripping) is a physical treatment process whereby air is thoroughly mixed with water to removed dissolved gasses and odour.
Coagulation: Addition of chemical to remove suspended solids.
Flocculation: A chemical flocculent, such as aluminium sulphate, is mixed rapidly with the water to remove mud.
Sedimentation: Also known as clarification- is the gravity-induced removal of particles.
Filtration: Involves the removal of suspended particles from water by passing it through a layer or bed of a porous granular material e.g sand. The filter water the passed through nozzles, the nozzles and sand in the filter beds must be cleaned periodically (This is known as back washing).
Chlorination: After filtration, the water looks much more cleaner than it was in the dam or river but it may not yet be healthy to drink because it may contain unseen micro-organism (bacteria) that are dangerous to the human body and can serious illness (such as diahorrea)
4.5 liters – 1 Gallon. 1 Liter – 100cl. 1 m3 – 5 drums or 200 liter volume.