What is the distillation of water? | WWD
What is the distillation of water?
Water distillation is a process in which water is boiled until it evaporates and condenses, leaving behind impurities with different boiling points.
Distillation produces clean, pure water. It is an effective method of water treatment to remove contaminants like bacteria, heavy metals, and chemicals.
How does water distillation work?
During distillation, water is boiled in a boiling chamber until it evaporates to vapor. This vapor is then captured and condensed in a clean container.
The majority of inorganic compounds and non-volatile molecules are unable to evaporate with water and end up in the boiling chamber.
Small-scale distillation units look a bit like coffee makers. They consist of a boiling chamber, a condensing chamber (or coils) and a storage container for clean water.
Steps for water distillation
The distillation process is as follows:
- The water is heated in a boiling chamber. The water is heated to a boil, which causes evaporation and the production of steam.
- Steam comes out of the boiling chamber. Steam from boiling water rises through a vent into a stainless steel condenser. All microorganisms, impurities and contaminants unable to transform into gas particles are left in the boiling chamber.
- The vapor condenses. Once the vapor reaches the condenser, it is cooled by a fan until it turns into water droplets. These droplets are now ready to be collected in a clean container – but first there is a final filtration step.
- The remaining contaminants are removed. All the impurities which evaporated and condensed with water can now be removed. Usually an activated carbon filter traps these contaminants using the adsorption process.
- Water collects in a storage container. After passing through the filter media, the water will drip from the spout of the still and into a holding container. This water is now clean, pure and ready to use.
Distillation can remove a wide variety of contaminants from water, including nitrates, iron, lead, hardness, and some microorganisms.
The overall efficiency of the distillation depends on the contaminants in the water. For example, some organic compounds, such as benzene, have lower boiling points than water.
This means that these contaminants will eventually recontaminate the water once it has condensed into a liquid form. Most stills use filter media, usually activated carbon, to trap any lingering contaminants before the water can leave the machine.
How long does it take to distill water
Distilling water is not a quick process. The average countertop water still takes between 4-6 hours to produce a single gallon of purified water. Water is produced one drop at a time.
This process can be speeded up by using a larger still, which can produce up to three gallons of water per hour, depending on the system. However, there is no acceleration of the distillation process. For those looking to produce large amounts of distilled water, the best alternative would be to use a water distillation plant.
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What is a water distillation plant?
A water distillation plant is a large-scale distillation solution that can be used for commercial or manufacturing purposes.
Distillation plants are much more efficient than single-use countertop stills. Depending on the number of units used, distillation plants can produce up to hundreds of liters of purified water per hour.
There are a number of industries that may require large-scale production of distilled water. These include laboratories, cosmetics manufacturers and automotive companies. Distilled water can also be used in canning products and brewing beer. Some bottled water manufacturers produce and sell distilled water.
A water distillation plant offers a higher level of performance, which is essential for industries that require large amounts of distilled water in their daily operation.
What are the benefits of distilled water?
Free from bacteria and viruses
Distillation removes bacteria, viruses and other microorganisms from the water. Whether distilled water is used for food, beauty, or drinking purposes, being free from potentially harmful microorganisms is a big selling point.
Purest water option
Few methods of filtering water are as effective as distillation. A still can produce almost 100% pure water. Other types of water treatment, on the other hand, can only be designed to target specific contaminants.
Many domestic uses
Distilled water has many uses around the home. It can be added to steam irons to prevent lime build-up and used in aquariums and car cooling systems. Distilled water can also be used for watering plants.
Cheaper than bottled water
People who make their own distilled water at home can enjoy pure, clean water for a much lower monthly cost than buying bottled water for drinking. However, because stills remove healthy minerals and vitamins from water, many people would say bottled mineral water always tastes better.
Industrial and commercial advantages
Distilled water is not only beneficial to the owner. It can also be used in the manufacture of cosmetics, laboratory experiments, canning production and for automotive purposes. Distilled water can also be used to sterilize medical equipment and surfaces.
What does the distillation of water take from the water?
Distillation removes a wide range of inorganic compounds from water, including metals like lead, iron, hardness minerals, nitrates, sodium, and most other dissolved materials. The process of boiling and evaporation is also effective in killing viruses, bacteria and other microorganisms.
While distillation is a very efficient form of water treatment, be aware that it may not remove all contaminants from a water source.
Distillation is not a foolproof treatment option for removing certain types of semi-volatile and volatile organic compounds (or VOCs for short).
Some organic compounds, like most pesticides, have higher boiling points than water. This means that they can be removed during distillation. However, some organic compounds have lower boiling points than water, which means that they too evaporate during the boiling process and condense with the water in the container.
These compounds must be removed during or before the condensation process to prevent them from contaminating the finished product. Testing a water source for contamination ahead of time can ensure that the right processes are used alongside distillation (if necessary) to remove these difficult contaminants.