Is desalinated water drinkable?

Is desalinated water drinkable? Does desalinated water meets the WHO potable water recommendations or it has to again treated for drinking purpose?

Taxonomy

• Drinking Water Security
• Filtration Solutions
• Water Treatment Solutions
• Water Quality
• Desalination
• Sustainable Desalination
• Drinking Water
• water treatment
• Water Treatment & Control
• Desalination

2 Answers

1. Thermal Desalination Process
   
   Thermal desalination processes produce distilled water, which is quite pure. Whereas seawater contains some 40 kilos of salt per ton, distilled water has only a few grams of salt per ton. In this sense it does not comply with WHO recommendations. However having a glass of it would not be a problem. The problem is preservation of such water since it will acidify, become corrosive and can easily be contaminated. Therefore water desalinated for human consumption is mineralised and chlorinated before dispatch for drinking purpose.

2. Potable water is drinkable.
   
   Thomas, potable water is drinkable. The definition of potable must be set by the corresponding national institution. Assuming that "desalinated water" is brackish or sea water treated by means of an arrangement of (crucial) pretreatments and Reverse Osmosis, in general it will not be drinkable. Due to the extremely low content of salts, this water is agressive and insafe to drink. The postreatment section in the treatment train will bring the desalinated water back to potability. In general, when dealing with brackish waters it is possible to blend the desalinated water with a partial stream of pretreated water (assuming there's no unwanted compound). On the other hand, desalinated sea water is treated by means of chemical dosage or reaction in order to elevate its salinity up to a minimun required level.