the diagram below shows how salt is removed from sea water to make it drinkable

The flowchart illustrates the various stages of the desalination of seawater to make it suitable for drinking.

The first stage is when the seawater goes through salt water intake to go to pre-treatment filter. By this stage, all of the garbage is removed and is returned to the sea by filter backwash. The step after this, the water is forced through a membrane at high pressure in order to allow water molecules pass through while salt and impurities are blocked and the seawater concentrate are returned to the sea. At the next step of this process, the water goes to the post-treatment with a number of chemicals such as lime, chlorine and fluoride. Then, it can be conveyed to the storage where it is intergrated water supply system.

As can be seen that, the production of this process is clean and safe for people because of the removal of harmful ingredients.