The diagram shows how sea water is processed to make it suitable for drinking through several steps. The process starts from the sea and ends with clean water being supplied to people.
First, salt water is taken from the sea through an intake point and goes through a pre-treatment filter. During this stage, some waste materials are removed and sent back to the sea through filter backwash. Then, the water is pushed through a special membrane using high pressure. According to the small diagram in the corner, this membrane has tiny holes that let water molecules pass through but stop salt and other impurities.
After passing through the membrane, the water receives additional treatment where three chemicals are added: lime, chlorine and fluoride. The treated water then moves to a storage area before it goes to the water supply system. It’s important to note that the sea water concentrate, which contains the removed salt, is sent back to the sea.
The whole process shows how modern technology can turn sea water into fresh drinking water through filtering and chemical treatment.