April 15, 2016 By Martin Last updated on April 30, 2016 The oldest method for production of pure water is the thermal method or distillation -water evaporation from the surface and condensation.
The basis of the process is the transfer of water in the vapour phase with its subsequent condensation.
Evaporation is achieved in various ways. In the process of steam formation with water molecules other solutes can enter the steam as indicated by their volatility. Now regarding the aforementioned fact… The main drawback of this method is the very high maintenance costs of the electricity needed to convert the water into the steam. Do you know an answer to a following question. What’s happening in the process of distillation?
The water molecules have the boiling point of 100°C or 212° Other substances have different boiling points.
The substance that boils at a lower temperature evaporates first.
Let’s consider the distillation. Of course, the substance that boils at a lower temperature evaporates first. Anyways, when the water has already boiled out, The boiling point of various impurities is higher. Theoretically, they will begin to evaporate. Anyway, theoretically after the distillation the absolutely pure water is obtained. Since the salt boils at a much higher temperature, There are practically no salts in the distilled water. If the water contains the oil drops they can be found also in the distillate.
Notice, organic substances, that have similar boiling point than that of water can slip in the distilled water. Distillation is used mainly in laboratories and factories, where That’s a fact, it’s needed.