By Rehan Iqbal
Water is essential to all life. A healthy body needs healthy water. There is a seemingly endless debate going on about the water that we drink. Spring water, mineral water, ionized water, there’s no shortage of water products that are being marketed as the essence to good health. Some of it is true, some is pure exaggeration.
Regardless of what marketeers want us to believe, it is common knowledge that tap water can contain any number of unwanted contaminants. Whether it’s harmful chemicals or metals, there is a genuine concern that the water supplied to our homes may not be all that healthy. It’s little wonder then that water filters and purifiers have become so popular. Most of us have considered the pros and cons of purifying the water supply to our homes.
As we begin researching water filtration systems, purifiers, deionizers, and water distillers, things seem to become way more complicated than we first thought. This article should help you gain some clarity on the matter. There are many questions that people want answered about water purity and its effect on our health. This topic is but one of them, the difference between distilled water and purified water.
You may also want to do more research, like the difference between a water filter and a water purifier, but it’s a good idea to start by looking at a water purifier vs water distiller.
What is Distilled Water?
By boiling water and then condensing it, the water is distilled. The processing involves extracting pure H₂0 in the form of water vapor which is a gas. By cooling the gas, it reverts back to a liquid, water that we can drink.
The science behind water distillation is the different boiling points for various elements. Water boils at 212°F (100°C) when at sea level. At higher altitudes, water will boil at a slightly lower temperature, because of the decrease in air pressure. Though, for most practical purposes, the boiling point at sea level is the accepted temperature. In the end, the relative boiling point of other elements in the water will also evaporate at a lower temperature when the atmospheric pressure is reduce. The relative effect remains the same.
Metals will boil at a much higher temperature than water. This means that as the water is converted into a gas (at approximately 212°), the metals in the water remain in a solid form and will separated from the water. Other elements, that evaporate at less than 212°, will convert into gas before the water boils. This means that some contaminants in the water, which may include pesticides and volatile organic compounds (VOCs), will evaporate with the water, and will condense when cooled.
Distilled water may still contain some harmful contaminants. Most bacteria cannot survive the high temperature of boiling water, so it is generally considered safe. However, the water will not be completely pure. Additional purification may be required to remove some elements that remain after the water has been distilled.
Generally, distilled water is used when metals can be harmful or affect the outcome of a particular reaction. Distilled water is common in laboratories and industrial applications where metals are not desirable. It is also used for water cooling systems.
Is Distilled Water Safe to Drink?
Yes, distilled water is perfectly safe for us and our pets. It will be free of bacteria but may contain some contaminants that are not entirely healthy, but still safe for consumption.
Because water distillation removes metals, some healthy minerals will also be removed. We generally consume these minerals as part of a healthy diet, or by taking mineral supplements, so distilled has little effect on the minerals that we need.
What is Purified Water?
A water purifier removes just about all contaminants found in water, like heavy metals, VOCs, pesticides, herbicides, bacteria, and harmful chemicals. Water is purified by using multiple stages of filtration and purification. The best way to purify water is by using revers osmosis (RO).
It is important to distinguish between filtered water and purified water. While a water filter can remove most harmful contaminants, it does not necessarily purify the water. Most water filters remove solids up to a certain size, generally around 0.5 microns. These filters usually include activated carbon which is good for removing chlorine and some other elements that affect the taste and odor of the water.
Basic water filters do not remove all the impurities in the water. Bacteria and some VOCs can remain, when using basic filtration methods. This is why high-end RO water purifiers will utilize many stages to include ionization and UV filtration, as well as other filter media to remove all contaminants in different stages of the filtration and purification process.
Water Distiller vs Water Purifier
Having identified the difference between distilled and purified water, you will want to decide which system will work best for you. There are pros and cons to using either a water distiller or water purifier. The latter being a more advanced RO water filtration and purification system.
Water Distillers
A water distiller for home is a relatively small device, usually a countertop water distiller. It is portable and easy to install. All you need to do is plug the water distiller into a power outlet, fill it with water and switch it on. After some time, you will have distilled water ready to use.
Because distilled water has no minerals it is virtually tasteless. Some don’t enjoy drinking distilled water. Apart from providing safe drinking water, distilled water also has practical advantages. It is recommended for steam irons and steam cleaners, as mineral deposits in the water can cause blockages and corrosion in these devices. It is also useful for topping up lead acid batteries in your car or RV batteries.
Water Purifiers
Using a basic water filter will not necessarily produce purified water. While some countertop water filters and filter pitchers can provide relatively pure water, the best method of purifying water is to use Reverse Osmosis. Though not all RO systems purify the water.
Reverse osmosis water purifiers are large systems that are installed in your home, connected to the main water supply. This can be an under sink RO water purifier, supplying a single faucet, or a whole house water purifier, supplying the main water pipe to your home.
Because RO water purifiers are complex systems and require installation, they are more expensive than basic water filters. The purified water is stored in a tank that ensures good water pressure and water on demand as needed. This also makes an RO water system quite bulky, requiring more space than smaller water filtration systems.
A reverse osmosis water purification system will usually consist of 3 to 10 stages. The first 1 – 2 stages utilize prefilters that remove debris and sediment from the water. This prevents the other filters from becoming blocked and prolongs filter life. A reverse osmosis membrane uses the water pressure form the utility to force the water through a dense membrane that removes solid particles as small as 0.5 micron. If the water pressure to your home is insufficient, you may require a pump to increase the pressure. This will add to installation and running costs, as the pump uses electricity.
Sediment and RO filters are common to all reverse osmosis systems but don’t actually purify the water. To remove all contaminants from the water, several more stages are needed. This usually includes 1 or 2 activated carbon stages (sometimes more). Carbon helps remove chlorine and other chemicals that affect the good health, odor, and color of the water.
Demineralizers will remove heavy metals and may also be done in more than one stage. This can be achieved by using a filter cartridge, containing demineralization media, or electronic methods, like ultrasonic demineralizers or a magnetic field.
Water ionizers or softening media can be used to remove hard minerals to soften the water. To remove bacteria from the water, a UV filter is used. Silver is also used to remove bacteria and pathogens.
Because the water purifier removes all the minerals, some of which are healthy and improve the taste of the water, an RO water purifier can include a remineralization stage. This adds heathy minerals and improves the taste of the water. Remineralization is often a post filtration stage; the minerals are added as the water leaves the storage tank. Other post filtration stages can include additional activated carbon filters and bacteria removal.
One of the greatest advantages to using reverse osmosis is that you can choose which stages to use. This allows you only spend money on the types of filtration and purification that actually need. You also have water on tap whenever you need it. You don’t have to wait for the water to be purified. A whole house RO system has the added benefit of supplying the all the faucets and water outlets in the home. It also protects the pipes and fixtures from damage caused by mineral buildup, and prevents staining of bathtubs, sinks, and showers.
Water softeners are also good for laundry and preventing unsightly residue on dishes after washing. They prevent damage to appliances like washing machines, water heaters, and dishwashers.
Some of the disadvantages will include the cost to install and maintain the system. Many of the filters require replacement at regular intervals (3 months to 1 year). An RO system requires permanent installation, it is not easy to remove if you relocate and they are not portable. Many RO water purifiers use water for media regeneration and backwashing which will increase water consumption.
A water distiller is not expensive to buy but does use quite a lot of electricity. While distilled water is not 100% purified, it is safe to drink and will not contain any hazardous metals. However, by removing minerals from the water, it loses most of its taste.
The greatest advantage of using a water distiller is that the water is good for appliances that can be harmed by metals in the water and for other practical uses, like cooling systems and batteries.
While RO water purifiers are the most expensive, they are generally considered the best way to provide pure filtered water to your home. They are convenient to use, as purified water is supplied directly to a faucet or the whole house. You are able to utilize multiple stages to improve quality, taste, and good health of the water in your home. A whole house RO water purifier will also protect pipes and fixtures.
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