How To Purify Water Using A Water Distillation System

From water condenser to distillation flask, all you need to know about the Water Distillation System. 

What is Water Distillation System?

Water Distillation works on the principle of selective evaporation and condensation to purify water. It is a method of separating impurities based on their differences in volatilities. Water Distillation System is the summation of all apparatus and equipments required to perform purification of water through distillation.

Impure water is heated to change to steam. The organic and inorganic impurities generally have boiling point higher than water. Hence they do not evaporate along with water and are left behind. The steam is then made to condense to obtain purified water.

Distillation effectively removes inorganic compounds such as calcium and magnesium to remove hardness in water. The boiling process also kills pathogens such as bacteria and certain viruses. Due to being heat intensive process, distilled water generally lacks in dissolved oxygen and hence the taste.

What is Water Distiller and Distilled Water?

Water distiller boils water into vapor and condenses it back into liquid form in a separate container. The condensed purified water obtained is distilled water and the entire process is distillation.

To make it more clear, it uses the same process as water cycle which supports life. Water distillation mimics the way the environment naturally purifies and redistributes water.

The heat from sun's radiation evaporates water from surface water bodies such as lakes and ocean, turning it into water vapor.
The water vapor rises and begins to cool.
The cooling water vapor condenses to form clouds.
Then it precipitates like rain, snow, and hail back to the land as purified water.
Similar is the cycle of distillation. Hence it is important to note that distillation is an extremely energy intensive operation.

Water distillation can reduce the levels of sediment, metals, and biological contaminants within the water. It can also remove harmful heavy metals like arsenic, lead, mercury, radium from water.

Difference Between Distillation, Purified Water & R.O?

Distilled water vs. purified water

Purified water is defined by the level of impurities found in the water. In general, the impurity load of dissolved solids in purified water should be below 10 ppm or parts-per-million.

Distilled water is a type of purified water. It had neither contaminants nor any minerals in it. Purified water do have chemicals and contaminants removed, but it may still contain minerals. This is the main difference between them.

Distillation vs. Reverse Osmosis (R.O)


Reverse Osmosis or R.O

Kills pathogens and separate inorganic and organic impurities from water by boiling and condensation.

Does not kill pathogens instead separate them along with other inorganic and organic impurities by forcing impure water through a semi-permeable membrane resulting in clean water.

It is an extremely energy intensive process

Uses less energy than distillation

Has near to no minerals in purified water

Eliminates most of the minerals still has more minerals than that by distillation.

Incapable of removing impurities with same boiling point as water. Activated Carbon Postfilter can be used along.

Capable of removing impurities irrespective of their boiling point.

Capable of removing impurities irrespective of their molecular size.

Incapable of removing impurities having molecular size same as that of water.

Takes a lot of time to operate

A quick process of water purification

The main cost is the cost of operation.

The main cost is the cost of membrane replacement.

Types of Water Distillation System


A common type is a single-effect distiller that can easily be set on your kitchen counter or in your office. You simply pour a measured quantity of water into the system and the water is distilled, collected, and filtered into a reserve for you to use.

Plumbing Distillers

These are units that can be installed into your home plumbing system or at your point of use. They distill water as you need it, making it a cost-efficient way to get the water distilled. They do require some maintenance, which includes draining off the sediments that accumulate at the bottom of the boiling chamber. These can cost between $300 to $1000 and will produce water for as low as $.25 a gallon.

Commercial Distillers

Larger operations use multiple-effect distillers that allow them to provide from 75 gallons up to millions of gallons of distilled water per day. They contain multiple boiling chambers, allowing for more water to be distilled at a time.

Water Distillation System


all apparatus and equipments of water distillation

Apparatus Required

  • Electric Heater                                                        
  • Distillation Flask  
  • Thermometer
  • Condenser
  • Pure water receiving flask
  • Activated Carbon post filter (optional)

The apparatus basically are classified into two parts: a heat source and a condenser. 


Uses the differences in boiling point of water and that of the impurities to separate them. 


  • Since water has a lower boiling point than almost all the other contaminants, the electric heater heats the untreated water in the boiling chamber.
  • Heating is continued until the water reaches its boiling point and begins to vaporize.
  • The temperature of water is then maintained at this level for it to vaporize while the contaminants are yet to reach their boiling point and hence remain in solid form.
  • Once the entire water has vaporized, the steam is then funneled into a condenser.
  • Remove the heat source and let the steam cool to liquid form in the condenser.
  • You can use an activated carbon postfilter to further purify any contaminant having lower boiling point than water.
  • Collect the pure water flowing into a receiving container.
    Activated carbon postfilter is optional to use. But it remains helpful in removing contaminants, like VOCs, that can exist in a gaseous state and may have escaped into the condenser alongside the steam. The activated carbon, through adsorption, eliminates any contaminants that may still pose a threat to human life. 

Time Required

It takes around 4-6 hours for a countertop water distiller to produce one gallon of distilled water. Like most high purity water filtration methods, the process of water distillation is a slow one. The water distiller produces purified water one droplet at a time.

Though larger, industrial-grade distillers are capable of producing water much faster. These units can produce anywhere from 2-3 gallons of distilled water per hour. While a standard countertop water distiller is designed to produce a single gallon of distilled water at a time, larger distillers have reservoirs as large as 12 gallons. 

Key Contaminants Removal

Water Distillation is known to remove almost all the contaminants, to name a few:

  • Fluoride
  • Lead
  • Leftover Chlorine and chloramine
  • Nitrates
  • Barium
  • Copper
  • Arsenic
  • Iron
  • Viruses
  • Pathogenic Bacteria
  • Algae and biofilm
  • Organic compounds
  • Dissolved salts and solids
  • VOCs and benzene (Activated Carbon Filter)


As with all home water treatment systems, distillation units require some level of regular maintenance to keep the unit operating properly.

  • Unevaporated pollutants left in the boiling chamber needs a regular cleaning.
  • Even with regular cleaning, calcium and magnesium scale may build a limescale overtime at the bottom of the boiling chamber. The scale eventually needs to be removed, preferably by hand scrubbing.
  • Regular cleaning will also inhibit any bacterial, algae growth and prevent mold from settling in. In addition to cleaning, rinsing your water distiller boiling chamber in between cycles can help keep the system clean.
  • Using white vinegar can also be helpful. Fill your sink with warm water and add in few drops of white vinegar. You can also use lemon or lime juice, sulfamic acid for the purpose. Submerge it in water. Allow it to soak in the solution for a few hours.
  • Empty the water distiller and rinse. Pour the solution down the drain and fill the distiller with water. Thoroughly rinse out the distiller with warm water from your tap several times.
  • Allow the water distiller to air dry before reuse. 


Distillation units generally costs around $300 to $1200. Portable units are even cheaper and can be purchased for less than $200.

(NOTE: Prices are subjected to market demand and can well be below or above the range stated.)

Impact: Analysis on Distilled Water consumption

Yes, definitely you can drink distilled water. It may lack in minerals and may not supplement you with essential minerals, but it has no harmful effects. It is water of utmost purity. But you need to know that water itself does not possess significant amount of mineral contents. Your body does not rely on water for its nutrient intake. Instead water extracts the required minerals from the fruits and vegetables you consume to deliver them to body cells.

Water itself does not furnish your body with nutrition. It is a false claim that distilled water leads to mineral deprivation in body. To quote the WHO,

“In general, drinking water has not been relied upon as a contributor of significant trace nutrients to daily intake, but rather as a serendipitous supplement whenever it occurs.”

Essential minerals like calcium, magnesium, sodium and iron should be obtained from diet or through vitamins and supplements. Water performs many vital body functions, but is not a source of nutrients. If you do desire minerals in your distilled water, adding mineral water supplements are still an option. Many of them are readily accessible online. These will add desired minerals back into your water or boost its pH.

Distilled water protects one from certain harmful chemicals like chlorine added in municipal water supplies for disinfection. It protects one from :

Fluoride preventing dental fluorosis.
Removing excessive salt from water - Desalination
People suffering from urinary stones and kidney stones, having to avoid calcium
The Journal of General Internal Medicine published a study on the mineral contents of different waters available in the US. The study found that "drinking water sources available to North Americans may contain high levels of calcium, magnesium and sodium". It encouraged people to "check the mineral content of their drinking water, whether tap or bottled, and choose water most appropriate to their needs".

Water filtration and distillation devices are becoming increasingly common in households. Home Water Distillers and bottled distilled water are easily available. Distillation is important in regions where water resources or tap water is not suitable for ingesting without boiling or chemical treatment.

Caution while using Distilled water:

You need to be careful while choosing storage container for distilled water. Since Distilled water lack nutrients hence it can leach chemicals from the container it's stored in. If you plan to use the water immediately, most containers will do fine. But for long term storage it's best to use glass or high-quality stainless steel.

Applications of distillation

The application of distillation can roughly be divided into 3 groups:

Home application
laboratory distillation
Industrial scale

The main difference between laboratory scale distillation and industrial distillation is that laboratory scale distillation is often performed batch-wise, whereas industrial distillation often occurs continuously.

Home Distillation Applications

Distilled water can be used for a wide variety of household appliances and cleaning tasks.


Fish are extremely sensitive to chemicals like chlorine or chloramine. Using distilled water for aquarium provides with neutral, purified water free from any contaminants. You can also remineralize it, creating a safe and healthy environment for your fish to thrive in.

Cleaning agent

Due to lack of minerals distilled water is a great cleaning agent. Your tap water may possess minerals that can leave stains like hard water stains. These white stains are the results of dissolved salts and minerals in water. Many people use distilled water as a final rinse on their car after washing it for stain-free wash.

Car batteries and Radiators

Tap water contains minerals, which may lead to limescale build-up and corrosion inside the battery. This will prematurely destroy the battery. Replacing tap water with distilled water eventually help prevent such irregularities.

Distilled water is also a perfect diluter of the coolant for your car’s radiator. Distilled water unlike tap water does not corrode the interior thus preventing energy loss. 

CPAP machines and Humidifiers

A Continuous Positive Airway Pressure (CPAP) machine is a common treatment therapy for sleep apnea. Sleep apnea is a sleep disorder that prevents people from breathing while they’re asleep. CPAP machines helps rectify by apply constant air pressure to the lungs of a person via a mask. This keeps the airway open and thus prevent any breathing problem while sleep.

CPAP machines have a humidification chamber to keep the air moist. This helps moisten the throat and nasal passage thus improving sinus and overcoming common cold. It is vital to only use distilled water in the CPAP’s humidification chamber. This is because distilled water does not leave contaminants behind when the humidifier in the CPAP machine evaporates the water. This prevent people from otherwise inhaling chlorine present in normal water.

Neti pots

Neti pots is a popular nasal cleaning and moistening method. A saline solution is used to flush a clogged nasal passage to prevent congestion.

It is highly recommended to use distilled water with Neti pots. This is because distilled water is 99% free of contaminants, ensuring pathogens and other harmful chemicals will not enter into your body. It helps ensure that the interior is sterile.

Laboratory and Industrial Distillation Applications

  • Water is distilled to remove salinity. Distillation is an effective and traditional method of desalination.
  • Cryogenic distillation for air distillation, separating its components, such as hydrogen and oxygen, which have medical and aviation applications. 
  • The distillation of crude oil in petroleum industry to produce petrol, diesel, etc.
  • The use of distillation on fermented solutions to produce distilled beverages with a higher alcohol content is perhaps the oldest form of distillation, known since ancient times.
  • Other forms of distillation: Batch distillation, Continuous distillation, Laboratory scale distillation, Simple distillation, Fractional distillation, Steam distillation, Vacuum distillation, Air-sensitive vacuum distillation, Azeotropic distillation, Short path distillation.

Pros and Cons of Water Distillation System



Free of pathogen and harmful inorganic minerals in water.

Removes taste and minerals like calcium and magnesium.

It may last around 10-15 years and covers cost of installation in long run.

Being mineral deficient it can pull in minerals from its container if stored for a long time.

Guaranteed water purity.

Slow process of purification taking around 3-6 hours.

Maintaining and replacing the carbon postfilter are quite inexpensive.

Highly energy intensive process consumes a lot of electricity for operation.


Drinking distilled water is not bad for your health. The water distillation produces water of utmost purity. It is completely mineral-free but again that's not harmful. It may not supplement the body with essential minerals but as long as you supplement it with your diet it is all good.

Clean, high-quality water is vital to healthy life. Water hydrates, lubricates and act as transportation in our bodies. It is so essential for proper functioning that our body is 70-80% water.

So it is important to make sure that the water we consume remains high-quality pure.


Wikipedia: Distillation

USGS: Deionized and Distilled water