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WATER TREATMENT PROCESS

Water treatment is a process of extracting pollutants from raw water to produce water that is safe for the human and
also for the chemical usage. Water also needs to be treated with its aesthetics, free of any obvious turbidity, odor and
unpleasant colors. Conventional treatment plants include the following processes:

1. Screening
Wood fragments, leaves, aquatic plants and floating sediments will be separated through the screening process. After
the screening, the raw water will flow into the streams or dams.

2. Aeration
The pumped raw water of the aerator. This process will produce oxygen from the atmosphere for the oxidation of the
iron and manganese which dissolves into insoluble forms for the purpose of removal. This process also helps to
remove unpleasant odors.

3. Coagulants and Flocculation
The coagulant process usually uses the alum to form microscopic particles into the water and permits the fine
particles to form a larger and heavier flocculation for the deposition process. The flocculation produced will trap the
bacteria and the colors present in the water.

4. Sedimentation / Precipitation
The floc is allowed to flow through sedimentation tank as much as possible for a long period of time to allow it to
settle. Clear water will be collected from the top. For lighter flocculation, different processes will be used which is the
DAF (Dissolve Air Filtration) an alternative method using the minute air bubbles (“micro bubble”). The floc will
combine the air bubble and float upwards. Clear water will be collected from the bottom of the tank. This process is
called Soluble Air Flotation.

5. Filtration
Filtering water that has been filtered through filters which trap the fine particles and bacteria. The clean water will then
get into the water tank. Filters are frequently washed using a backwash method through a combination of air and
water mixture to ensure smooth operation.

6. Chlorination / pH Adjustment
The water in the clear tank will be disinfected to kill any residual microorganisms in the water after the filtration.
Chlorine chloride or chlorine compounds are commonly used for the purpose of disinfecting microorganisms and
making them safe for drinking water. The pH level is altered using lime or soda ashes. Suitable pH value is required
to avoid corrosion of the water pipe (low pH which is acidic) and to not form a sediment on the water supply system
(high pH which is alkaline).