Distillation is perhaps the oldest method of water purification. The distillation process consists of heating contaminated water until it vaporizes becoming steam. The vapor then rises into a condenser where it is cooled and returns to a liquid state, leaving most contaminants behind in the boiling water. The impurities that tend to remain after the distillation process are those with boiling points lower than that of water. These contaminants vaporize before the water does and join the water vapor in the condenser, thus persisting in the distilled water at a more concentrated level. Herbicides and pesticides are an example of some organic contaminants which water distillation fails to remove effectively.
One common concern regarding distilled water is that it tends to be acidic when produced. As the contaminated water is vaporized in the distillation process, it absorbs carbon dioxide from the air which affects the pH of the water. Distillation also strips water of minerals, producing water that tastes flat. Acidity in foods and drink are connected with numerous health issues with prolonged ingestion. This is perhaps one of the reasons distilled water was labeled in stores as ‘not for drinking’ in the 1950′s; Its recommended use at the time was for steam irons and car batteries.
The lack of oxygen and minerals in distilled water has earned it the term ‘hungry water’ and is used more for industrial applications than it is for drinking. Because conflicting reports concerning the acidity of distilled water exist, if you choose this method we strongly recommend that you purchase an accurate pH testing meter(pH strips tend to be inaccurate) to confirm the pH of your water yourself.
- Removes a broad range of contaminants
- Water has a flat taste and is void of trace minerals.
- It tends to be acidic and requires great care to ensure pH balance and water purity
- Some contaminants carry over at more concentrated levels
- Consumes a large amount of energy to be produced