Both reverse osmosis water and deionized water can remove contaminants from water, so what is the difference between them? In this article, you will learn the difference between reverse osmosis and deionized water. This information lets you determine which water filter is best for you.
What is reverse osmosis water?
Reverse osmosis water refers to water that has been treated by the RO system. Reverse osmosis is an advanced membrane separation technology. Its core is to use reverse osmosis membranes to separate and remove various ions, molecules, organic matter, microorganisms, and other substances in water. Through the filtering effect of reverse osmosis membranes, suspended matter, organic matter, heavy metals, bacteria, viruses, and other harmful substances in water can be removed to obtain high-purity water. This water has the characteristics of low mineral content, high purity, and low bacterial content.
How does the RO system work?
Here's how the RO system works:
Pretreatment: Water is first pretreated to remove particles, organic matter, and chlorine. This helps protect the R0 membrane from becoming contaminated or clogged.
Pressure and separation: Water is injected into the RO water system and pushed toward the R0 membrane through a series of pre-filters and pumps. The R0 membrane is a semi-permeable membrane that only allows water molecules to pass through while blocking most solutes, ions, bacteria, and organic matter dissolved in the water.
Separation process: When water molecules pass through the R0 membrane, most solutes, ions, and microorganisms are retained on the other side of the membrane. These retained solutes and ions form concentrated wastewater and are discharged from the system. At the same time, pure water molecules pass through the RO membrane, are collected, and become the output water of the RO system, called pure water.
Wastewater treatment: The R0 system produces two types of water: pure water and wastewater. Wastewater is rich in solutes and ions that are retained by the RO membrane and need to be properly treated for discharge or utilization.
Related: How does a water filtration system work
What is Deionized Water
Deionized water is considered water that is made up of zero-charged particles called ions. Ions contain either a cationic or anionic charge. Dissolved solids are an accumulation of these two ions, which is also what makes up the higher percentage of contaminants in water. When water passes through a deionization system, these contaminants are effectively separated from the water, resulting in clean, pure water. In theory, the deionization process eliminates all remaining salts in the water.
How does a deionized water system work?
The working principle of a deionized water system is to use the ion exchange properties of specific materials to remove ions from water through ion exchange, so that the ion concentration in the water is reduced to an extremely low level as much as possible, thereby obtaining high-purity water.
Deionized water is sometimes confused with distilled water, but the two are not the same. Distilled water is obtained through a boiling and steaming process. Distilled water can still be ionized, and although it is purer water, deionized water is purer.
What are the disadvantages of deionized water?
When a deionized water system processes a large amount of water, it is necessary to consider the scale and capacity of the equipment, because its processing efficiency and output are closely related to the scale and capacity of the equipment, and larger-scale equipment will take up more space and resources.
The deionized water system is not very effective in removing some difficult-to-remove organic and inorganic substances, so in actual applications, different treatment methods need to be selected according to different water qualities.
The maintenance and care of the deionized water system is relatively complicated, and the resin in the equipment needs to be replaced and cleaned regularly, otherwise, it will affect the service life and treatment effect of the equipment.
What is the difference between reverse osmosis and deionized water?
Difference in working principle
Reverse osmosis mainly relies on physical filtration to remove most of the dissolved solids and microorganisms in the water through a semi-permeable membrane. By applying pressure to the water source, water molecules are forced to pass through the membrane, leaving behind pollutants. RO systems can effectively remove many pollutants, including salts, particles, bacteria, viruses, etc.
Deionization technology mainly uses ion exchange resins to remove dissolved ions in water, thereby producing extremely high-purity water. However, for organic matter and microorganisms, deionization technology cannot effectively remove them.
Difference in water quality
Reverse osmosis water can remove most impurities in water, including minerals, and it is very pure water. However, very few reverse osmosis waters contain minerals. Deionized water contains almost no ions and its purity is very high.
Maintenance and cost differences
The maintenance of the reverse osmosis system requires regular replacement of the RO membrane, and regular cleaning and disinfection of the RO equipment to ensure that the RO system can play its best filtering effect. The maintenance of the deionization system mainly requires regular replacement of the deion exchange resin to ensure the normal operation of the deionization system.
Although the initial cost of the deionization system is low, the cost of replacing the deionization resin will increase later. The initial cost of the RO system is slightly higher than that of the deionization system, but the subsequent cost will be very low. Because you only need to replace the RO membrane regularly, and the life of the RO membrane is usually longer than that of the deionization resin.
Difference in scope of application
Generally speaking, reverse osmosis systems are widely used in homes, outdoors, aquariums, and most industrial applications. Deionization systems are more suitable for laboratories and high-tech manufacturing industries.
Which water purification system is best?
Historically, people drank more surface water from streams, rivers, and lakes. However, with the use of irrigation and wells, groundwater has become a water source, and the mineral content of groundwater is much higher than that of surface water.
Now people think that the quality of well water is not good, so they choose to drink bottled water. Bottled water is also polluted. Bottled water is usually packed in plastic bottles. Long-term purchases will produce a large number of plastic bottles, causing serious pollution to the environment. Studies have found that bottled water may contain microplastics. Long-term drinking may have an impact on health.
Therefore, in daily drinking water, you need to test the water quality at least once a year. If you find that the color and taste of the water quality have changed, you need to test and filter it immediately. So, which water filter is the best, reverse osmosis water or deionized water?
If you want to choose between reverse osmosis water and deionized water, then we think a reverse osmosis water filter is your ideal choice. Because reverse osmosis can remove most of the pollutants in the water. Deionization filters require more maintenance, but the advantage of deionization is that it can soften water and remove pollutants.
ITEHIL offers the best reverse osmosis water filters
It is very important to choose a trustworthy water purification system brand. As a leader in the field of water purification, ITEHIL provides advanced reverse osmosis filtration technology. ITEHIL portable water filter uses PP cotton + activated carbon and RO membrane for multiple filtration, which can filter almost all pollutants in the water. It is portable and lightweight, easy to operate, and is an ideal choice for many outdoor enthusiasts to obtain safe drinking water.
Frequently Asked Questions
Why is deionized water not suitable for long-term drinking?
Deionized water is high-purity water and does not contain any minerals needed by the human body. Long-term drinking of deionized water can lead to mineral deficiency. However, reverse osmosis water retains some trace minerals and is suitable for drinking.
Are reverse osmosis and distilled water the same?
Both reverse osmosis and distilled water can produce deionized water, also known as pure water, but the manufacturing processes are different. Reverse osmosis uses membrane separation to remove ions from water, while distilled water is produced by evaporation and condensation.
What is equivalent to deionized water?
Deionized water has a very high purity. It is made by removing positive and negative ions from water through ion exchange resin, making it close to pure water. Other waters with similar properties to deionized water include distilled water and pure water.
Can deionized water replace reverse osmosis water?
Deionized water is not suitable for directly replacing reverse osmosis water, especially for drinking water. Although deionized water is very pure, it does not contain any minerals, and long-term drinking may have an impact on health.
Why does deionized water have lower conductivity than reverse osmosis water?
Deionized water has low conductivity because it has almost all ions removed, while reverse osmosis water may still contain trace amounts of dissolved salts and minerals, so the conductivity is relatively high.