Distillation...A Process for Purifing Water
The process of distillation has been known and used for millennia. Its
use has primarily been employed as a method of producing alcoholic
beverages like whisky orvodka, but the process also works as a
technique of water purification.
process utilizes heat to vaporize water. The
object is to separate pure water molecules from contaminants
with a higher boiling point than water.
Water is first heated until it reaches its boiling point and starts to
evaporate. The temperature is then kept at a constant to ensures
continued water evaporization and stops drinking water contaminants
with a higher boiling point from evaporating.
Next, the evaporated water is captured and guided through a system of
tubes to another container. Finally, the steam cools and condenses back
into its original liquid form. Contaminants having a higher boiling
point than water remain in the original container.
Removed From Water by Distilling It
Distillation can remove nearly all impurities from water. Compounds
- Heavy metals like Lead, Arsenic, and Mercury
Not Removed From Water by Distilling It
- Bacteria, Viruses, and Protozoan cysts
Removing the organic compounds in water by distilling it can vary
depending on chemical properties of the contaminant. They do not remove
chlorine, chlorine byproducts, pesticides, volatile solvents, VOCs such
as enzene and toluene with boiling points close to or below that of
water will vaporize along with the water as it is boiled in the
These compounds will not be completely removed unless another process
is used either prior to the water entering the distiller or before
No one piece of treatment equipment manages all contaminants. All
treatment methods have limitations and often situations require a
combination of treatment processes to effectively treat the water.
Pros and Cons:
Distillation, similarly to reverse osmosis, will provide mineral-free
water to be used in laboratories, for printing purposes, or medical
facilities were mineral-free water is needed. It is often used as the
preferred water purification method in developing nations, or areas
where the risk of waterborne disease is high, due to its unique
capabilities to remove bacteria and viruses from drinking water.
There are has several qualities that make it undesirable for the
purification of municipally treated water. Most synthetic chemicals,
including pesticides, herbicides, and chlorine have a lower boiling
point than the boiling point of water. Synthetic chemicals are the
major contaminants remaining after municipal treatment and distillation
does not remove
these harmful chemicals.
Also it provides mineral-free water that can be quite
dangerous to the body’s system when ingested, due to its acidity.
Acidic drinking water strips bones and teeth of valuable and essential
mineral constituents. A good collidal mineral supplement should be
added to any water used for drinking.
Lastly, it is an incredibly long and wasteful process.
Typically, 80% of the water is discarded with the contaminants,
producing only one gallon of purified water for every five gallons