As the name suggests, demineralized water is water devoid of all mineral impurities. Specially used for a range of industrial purposes, this type of water is prepared by the method of deionization.
Besides, other methods like distillation, reverse osmosis, and backwashing of filters can also be used, but they aren’t as effective as the first one.
Although it has removed all its mineral impurities, demineralized water is also available to consumers. Moreover, it is also widely used in car batteries, cooling towers, boilers, and pharmaceutical manufacturing industries.
This article will teach about demineralized water and why you should consider using it.
Why is it important to use demineralized water?
It is important to use demineralized water as its impurities like calcium, magnesium, and sodium hamper the validity of several industrial processes. These impurities contaminate the mechanism and end up degrading the outcome as well.
Apart from this, demineralized water is perfectly suitable for scientific and pharmaceutical processes to avoid contamination. Well, it is also essential for water to be demineralized so that it can be ideally used on sensitive surfaces without causing corrosion. Even though demineralized water is the only preference when it comes to the automotive or electronics industry.
Owing to the importance of demineralized water, its benefits for specific industries are as follows:-
💧For food and beverage
Despite technologies like membrane filtration, demineralized water is widely used for several food processing applications. It is used because the production of foods and beverages requires ultrapure water at every step of their manufacturing process.
Especially used for sanitizing containers and equipment, demineralized water is a part of the manufacturing process.
💧For pharmaceuticals and cosmetics
Cosmetics and pharmaceutical equipment are something whose safety and quality are of great significance. Therefore, to control the genuineness of these products, deionized or distilled water is used for manufacturing them.
For different uses, different methods of demineralization are practiced. The water used for cleaning and rinsing is produced by reverse osmosis. However, distilled water is used for typical formulations.
Refineries utilize demineralized water to feed their high-pressure boilers. In this case, water lacking minerals is the only choice as dissolved impurities and hardness can damage the facility’s equipment. Moreover, soft water is also not preferred as softening is not enough for most high-pressure boilers.
High-quality water with minimum contaminants is the ideal requirement for most high-pressure boilers. Hence, demineralized water is the best match for it.
Demineralized water is often used for feeding high-pressure boilers and generating steam. In the power industry, the boiler that energizes turbines by the steam it produces requires a much more complex water treatment. The treatment that removes as many impurities as possible is suitable for this process.
During the steam production process, many condensate and gases are formed. The particulates produced get recycled as a part of the boiler’s feed. However, dissolved gases like carbon dioxide and oxygen are still present and may cause corrosion. Therefore, to remove those, demineralization or deaeration devices are used.
💧For petrochemical and chemical
For both petrochemical and chemical industries, the water used to feed boilers should be high purity. The ideal quality of water these industries prefer can only be accomplished by demineralization.
Moreover, demineralized water is also used to treat cooling tower blowdown effectively.
Apart from these, other industries like mining and chemical production have a wide application of demineralized water. Even for cleaning glassware in laboratories and electrocoating, this water is preferred.
So, these are the main reason behind why is it important to use demineralized water.
What is the difference between distilled water and demineralized water?
People often mistake demineralized water and distilled water for being the same because of their similar applications. However, this is not the case; both forms of water are different from each other. They are produced differently and also have distinctive effectiveness.
Demineralized water is prepared by deionization and is also known as demi water or deionized water, whereas; distilled water is purified by boiling the water and then re-condensing it. Besides, the major difference between distilled and demineralized water lies in the concentration of organic contaminants.
Distilled water contains fewer organic contaminants as boiling and condensing kill most of them. On the other hand, deionization does not eliminate the uncharged molecules of bacteria and viruses, increasing their concentration in demineralized water.
Although it depends completely upon the production method, demineralized water has fewer mineral ions than distilled water. Further, the mechanism of deionization is much cleaner than distillation and leaves behind less scale during its installation.
Why is demineralized water used in boilers?
The fact that demineralized water lacks all sorts of minerals makes it the best feed for high-power boilers. This is because it does not contain any impurities and thus, is essential for avoiding the build-up scales in boilers.
Similarly, using demineralized water prevents the accumulation of scale in heat exchanger tubes that would occur with raw potable water.
Well, the raw water from canals cannot be used for steam formation as it greatly affects the heat transfer rate of the power plant. Moreover, the impurities present in potable water erode the turbine blades when entered along with the steam.
What is the pH of demineralized water?
The pH value of demineralized water ranges from 5.5 to 7.0. It is slightly acidic because of the carbon dioxide that dissolves in it from the air when left alone. This dissolved carbon dioxide reacts with the water and forms carbonic acid.
Therefore, freshly prepared demineralized water has a neutral pH of 7. However, on capturing carbon dioxide from the environment, the pH value decreases to 5.5.
Is demineralized water OK to drink?
No, consumption of demineralized water without any proper enrichment is not suitable for drinking. According to World Health Organization (WHO), long-term consumption of demineralized water may result in several health risks and can even be fatal.
The importance of demineralized water is quite evident from its wide range of applications. Every field, from industrial to scientific, reaps the benefits of such water. However, due to its lack of minerals, demineralized water is not fit for human consumption.