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Even though some people might occasionally refer to reverse osmosis water and demineralized water interchangeably, they are not really the same thing.
Let’s shed some light on the similarities and differences of reverse osmosis vs demineralized water and find out which one you should use!
The main difference between demineralized water and reverse osmosis water is that demineralized water is specifically stripped of its mineral contents, while reverse osmosis water is filtered more thoroughly and, theoretically, contains no more impurities/contaminants at all.
Also, there are different methods to demineralize water, one of which is reverse osmosis. But there’s also distillation, deionization, etc. On the other hand, reverse osmosis water can only be produced using reverse osmosis.
The applications of demineralized water and reverse osmosis water also differ. Demineralized water is used where you need water with low mineral content, such as in swimming pools, whereas reverse osmosis water is basically free from minerals and any harmful contamination making it suitable for drinking water production etc.
Demineralized water has been treated to remove most to all minerals from it, like calcium, sodium, magnesium, bicarbonate, fluoride, iron, copper, and various others.
In other words, water demineralization is achieved through specific treatment methods that focus on removing minerals. Some of those methods may also remove other impurities, while some are specifically focused on minerals alone.
The amount of minerals left in demineralized can water go below 10 ppm (TDS).
By the way, demineralized water is also called DM water or demin water.
Demineralization is sometimes confused with deionization. However, just like reverse osmosis, deionization is only one way to demineralize water.
Water demineralization can be done in multiple ways, such as:
Reverse osmosis water is water that’s been passed through a reverse osmosis membrane. The result is pure, fresh water without any impurities or contaminants – including minerals. Reverse osmosis water is very popular in places with heavily contaminated natural water sources and is thus often used by domestic users for household filtration. But there are also plenty of commercial and industrial applications of reverse osmosis which we’ll discuss soon.
Reverse osmosis is a bit complicated to implement due to the materials required, but it’s actually a simple process beneath the surface. It all boils down to the reverse osmosis membrane – a special filter element lined with very fine pores that are so small that only water molecules can pass through them. This happens when water is pushed against this membrane at a high level of pressure. All contaminants in the original water stream are rejected and get sent away.
Minerals in drinking water provide a health benefit which is why demineralized water plays a minor role in home environments. However, many commercial and industrial processes require water with low or even no mineral content:
Reverse osmosis water is pure water with almost no minerals but also no harmful contaminants mixed in. The benefits of that should be obvious for the end user, especially if you live in an area with particularly heavy water contamination.
In addition, many desalination plants around the world use reverse osmosis as their primary tool. On an industrial scale, the process is easy to scale up and quite cost-effective.
Other applications of reverse osmosis include:
So, RO water vs demineralized water – which of the two is better? None really.
Reverse osmosis water and demineralized water are just different, and which of the two to use should depend on the application (see above).
If you want to improve the quality of your drinking water at home, reverse osmosis is the way to go.
If you have any questions about RO water vs demineralized water please don’t hesitate to leave a comment below!
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