A Guide to Reverse Osmosis Water

Reverse osmosis is widely considered to be one of the most effective water filtration methods. It’s a simple and successful way of producing water that has had unwanted contaminants removed, and is safe and chemical-free.  

If you’re interested in investing in a reverse osmosis water system for your business, we’ve answered some of the questions you may have.

How does a reverse osmosis water system work?

An RO system contains a semi-permeable membrane that most unwanted impurities cannot pass through. Water is pushed through the RO system at high pressure, and small particles and contaminants are left behind. They are then removed from the water, leaving a steady flow of nearly pure water molecules. The wastewater containing the unwanted contaminants can be flushed to waste or reused in a different application.

What are the benefits of RO water?

The benefit of using a reverse osmosis system is that you are provided with a supply of near-pure water that’s been cleaned on a molecular level and is free of impurities. This is great for any business that needs a continuous supply of treated water.

Because of the purity of RO water, commercial reverse osmosis systems are popular within the food and beverage industries, as well as automotive and pharmaceutical applications.

Other benefits include:

  • No downtime, as RO plants do not need to regenerate
  • RO systems are safe and chemical-free
  • You can repurpose the wastewater from an RO system
  • RO systems are efficient and low energy

What effect does RO water have on the pH of the water?

pH is a scale used to measure how acidic or basic a liquid substance is. The scale ranges from 0 to 14, with 7 being neutral (pure), 1 acidic, and 14 alkaline. Because reverse osmosis removes the minerals in water, the water will then react with carbon dioxide upon exposure to air. This forms carbonic acid, which lowers the water’s pH. The resulting pH will depend on the incoming water feed.

This makes RO water is slightly more acidic than completely purified water. RO water typically has a pH balance of 6.0 – 6.5pH. 

What does reverse osmosis remove from water?

Reverse osmosis will remove most common contaminants from water. For example:

  • Sodium
  • Chloride
  • Copper
  • Lead
  • Nitrate
  • Iron
  • Zinc
  • Arsenic

Reverse osmosis membranes are capable of rejecting practically all particles, bacteria and organics >300 daltons molecular weight (including pyrogens).

Is RO water drinkable?

Reverse osmosis water is almost pure h20, which is technically safe for drinking. However, we wouldn’t necessarily recommend it. Amongst the contaminants removed from water in the RO process are healthy minerals like magnesium, calcium and sodium. Because of this, RO water has an altered taste and doesn’t quench thirst like regular drinking water due to its lack of minerals.

If you want to use your RO treated water for drinking, we’re able to install a blend valve that puts mains water back into the drinking water supply.

What are the dangers of RO water?

Reverse osmosis water is completely safe for use in manufacturing as long as the RO machine is installed and operated correctly. The safety questions generally arise when it comes to reverse osmosis in drinking water. According to guidelines from the World Health Organisation (WHO), demineralised and reverse osmosis water could actually have an adverse effect on humans due to its lack of healthy minerals, making it unsuitable for long-term consumption:

“Demineralised water that has not been remineralized, or low-mineral content water — in the light of the absence or substantial lack of essential minerals in it — is not considered ideal drinking water, and therefore, its regular consumption may not be providing adequate levels of some beneficial nutrients… Sufficient evidence is now available to confirm the health consequences from drinking water deficient in calcium or magnesium.”

Generally, reverse osmosis water isn’t necessarily unsafe, but it’s not the best option for long-term drinking water. 

How long will water keep in RO?

Reverse osmosis water does not behave like standard tap water, so it must be stored and used differently. Tap water contains chlorine to help reduce the chance of bacteria growth. Since RO water is stripped of chlorine, its shelf life is reduced.

As soon as reverse osmosis water comes into contact with oxygen, it begins to react with it. The water picks up tiny fragments from the air which causes the quality of the water to decrease. For these reasons, we recommend that RO water is not stored in a tank for longer than 24 hours. This may differ slightly depending on the water’s intended use. For industries like pharmaceutical and food, water quality is a high priority and strict storage rules should always be followed. This may be less of a concern in industries like car or glass manufacturing, for example.

To best preserve its shelf life, RO water should be stored in an airtight container in a dark place. You can also add additives to the water to further increase its longevity. 

We hope this taught you more about reverse osmosis water systems. If you have any further questions, or would like to talk about getting an RO system for your business, our team of experts are on hand. Contact us today.