HomeBLOGReverse Osmosis (RO) Water Purification Process

Reverse Osmosis (RO) Water Purification Process

The process of Reverse Osmosis (RO) was introduced in 1748 by Jean Nollet. Nollet was a French physicist and clergyman who performed various experiments using electricity and discovered the process of Osmosis.

It is one of the most common methods to produce desalinated water for human use. But for more than a couple of centuries, this method was overlooked entirely.

Let’s discuss how this water purification method compares with other methods.

So, scroll down to read further.

A Brief History or RO

The process of reverse Osmosis was discovered back in the mid-1700s. However, it remained overlooked for more than two centuries. It was only observed more than 200 years later in the laboratory when the University of California (LA) examined the desalination of seawater with semipermeable membranes.

Experts from the university and University of Florida successfully produced freshwater using seawater in the mid-50s. The flux was too low to make the project commercially viable.

Later, Filmtec Corp’s John Cadotte discovered that these high flux membranes could be made using interfacial polymerization of trimesoyl chloride and phenylenediamine. And this method has become universal now.

By 2019 more than 16,000 desalination plants work all across the globe, and they can produce more than 25 billion gallons per day of desalinated water for human consumption.

What is Reverse Osmosis?

Water to go for a water purification system that will provide you with great tasting water, then this is your choice. The process of Reverse Osmosis is the most cost-effective and most popular method for water purification that is available today.

An RO water filter works by enforcing water through a semipermeable membrane. As a result, all contaminants are left behind, flushed down the drain. But the clean water for drinking collects within a holding tank.

How Does Reverse Osmosis Work?

The entire process of Reverse Osmosis is simple to understand. Water pressure pushes tap water right through a semipermeable membrane. All the contaminants are left behind as the water gets pushed through the membrane.

These contaminants include any inorganic solids. This price works slightly differently from the standard filtration process. In the latter, all the impurities are collected within a filter media.

However, the RO process pushes water through various filters and collects the clean water into a separate holding tank. As a result, all the impurities flush down the drain.

An RO system is installed right under your kitchen sink. These under-the-counter RO systems have a holding tank and feature multiple filtration phases.

Phase 1

It is a pre-filtration phase to protect the membranes in a unit by reducing any fine material that clogs the system.

Phase 2

In the second phase, chlorine is filtered out since it can damage the thin-film materials of the membrane.

Phase 3

In this stage, the semipermeable membrane removes various health and aesthetic-related contaminants. From here, the water goes into a storage tank to hold the water that has been treated through the process.

Phase 4

The final stage of the RO process is commonly the post-filtration carbon filter stage. It will remove any impurities from the water and make it taste and smell better. You can also call it a polishing stage for the water.

What Contaminants Will Reverse Osmosis Remove from Water?

There are various contaminants that the princess of Reverse Osmosis removes from the water. These are:

  • Lead
  • Fluoride
  • Nitrates
  • Sulfates
  • Pesticides
  • Detergents
  • Chloramine
  • Chlorine

The impurities filter out easily when the RO water pressure pushes tap water through the RO membrane and some additional filters, including carbon and sediment filters.

What remains is the great-tasting water that is free from any impurities. Keep in mind many Reverse Osmosis units feature four or five stages within the filtration process to provide you with optimal quality of water.

Most RO systems look very similar and have pretty much the essential components. The filtration semipermeable membranes are there, along with a carbon filter. But these systems vary when it comes to producing the water quality in the storage tank.

The basic components include:

  • A valve for cold water lines
  • One or more pre-filters
  • A Reverse Osmosis membrane
  • One or two post-filters such as carbon or any other sediment filters
  • An automatic shut-off valve
  • A check valve
  • A flow restrictor
  • One or two storage tanks
  • A faucet
  • And a drain line

Reverse Osmosis vs. Osmosis

What is Osmosis?

The process of Osmosis is a natural phenomenon that takes place in all living beings.  Water molecules move from higher water potential areas to a lower one through a semipermeable membrane. Osmosis occurs right along the concentration gradient. Therefore, it doesn’t need any energy, as it is a passive process.

How is RO better than Osmosis?

In RO, a pressure greater than the osmotic pressure is applied to the water, and it pushes through a semipermeable membrane along the concentration gradient.

As a result, water goes through the membrane from a lower water potential to a higher one. But other containers will not pass through the membrane. But RO does need the energy to create that pressure and makes it different from the osmosis pressure.

RO is much better in removing ions and heavy metals, among other contaminants and impurities. And these features make it a better option than the osmosis process.

Reverse Osmosis vs. Distilled Water

What is distilled water?

Distilled water is water that we get from boiling it. We capture the condensation and allow it to condense back into the water.

This princess is slightly different from what municipalities do to purify your water. Simply boiling the water will kill any microbes or bacteria but not remove any chemicals or other contaminants like minerals.

How is RO better than distilled water?

Distilled water might taste or look like what you get from RO systems. But distilled water still has some impurities in it, like minerals. RO water doesn’t contain any minerals.

That is why at times, you will notice a slight difference in the taste of RO water from distilled water. Getting distilled water is a hefty process as it requires plenty of energy to run. On the other hand, RO is cost-effective and easy to use, and you will only have to turn your faucet on to get your purified water.

Reverse Osmosis vs. Water Softener

What is a water softener?

A water softener conditions water. It uses ionization for replacing claims and magnesium ions within the water with salt and sodium ions.

Hard water has a high concentration of calcium and magnesium ions and can cause dry skin, faded laundry, castling in pipes, and water spots on glasses. However, you can solve these problems and enjoy great-tasting water with a water softener.

How is RO better than water softener?

With Reverse Osmosis, the process of purification becomes smush simpler. This is because water softeners condition the water while RO purifiers it. Therefore, it is naturally a better alternative as you will only have to turn the tap on to get your purified water.

But you can use a water softener in the tendon with your RO systems to keep some pressure on them. Water softeners can reduce the calcium and magnesium ions before the water even hunters the RO system. So, you can use a water softener with your RO system to make them more long-lasting.

Reverse Osmosis Water vs. Mineral Water

What is mineral water?

Mineral water is somewhat polar opposite to RO water. But mineral water also goes through a purification process. Therefore, it has high mineral content than regular tap water.

Most filtration plants use tap water and purify it synthetically and minerals like magnesium and calcium. People prefer drinking mineral water due to its taste. It is much better than RO water.

How is RO better than mineral water?

Mineral water is better in terms of taste compared to RO water. RO water has been stripped of all the minerals in the final filtration process.

These minerals are synthetically added to the mineral water, making it taste good. There is only the taste difference between the two, and mineral water has minerals. But it filters using RO, so there is not much difference between the two.

Reverse Osmosis Water vs. Alkaline Water

What is alkaline water?

Alkaline water has a huge advantage over RO water, and that is it tastes much better than the latter. This is because alkaline water has a higher pH level (9.5+).

This water takes care of the development of acidity in our bodies, and it has to be balanced out. Poor diet, environmental pollution, and stressful lifestyle all continue to cause body acidity.

Alkaline water has minerals that our body can conveniently consume and balances out the pH level. It boosts calcium intake in our bodies. Alkaline water is as good as milk because milk can cause acidity. It ionizes hydrogen and has minerals like sodium, magnesium, calculus, potassium, and others.

How is RO better than alkaline water?

RO water doesn’t have any minerals in it as the filtration process has drained them all. This deficiency can make the water more acidic.

And it can affect your health in the long term. Therefore, alkaline water is better than RO water as it balances out pH levels and makes it less acidic. So, RO water is not better than alkaline water; it is the opposite.

Reverse Osmosis vs. Refrigerator Filter

What is a refrigerator filter?

Most fridge filters use activated carbon, and it is the same process that most standard pitcher filters use. In these setups, filters have carbon granules and trap various contaminants such as chlorine.

But only relying on carbon filters will not provide you with the best results. It will not filter out hard water minerals and deal with copper, arsenic, and lead. It is also ineffective against viruses and bacteria.

How is RO better than a refrigerator filter?

RO is undoubtedly the better choice because fridge filters only have regular carbon filters, and it uses carbon filters as one of its filtrations phases.

It is going to provide you with better results. RO is also more effective in getting rid of bacteria and viruses and removing any hard water minerals. So, RO systems are certainly better than fridge filters.

Reverse Osmosis vs. Ultrafiltration

What is ultrafiltration?

Ultrafiltration is a powerful water filtration system that uses a hollow fiber membrane that filters out impurities and contaminants such as macromolecular organics, bacteria, and viruses.

However, it still allows some salts like sodium and other organics to pass through. As a result, impurities such as arsenic, calcium, fluoride, lead, magnesium, nitrates, sulfates, and TDS remain in your filtered water.

How is RO better than ultrafiltration?

RO is better than ultrafiltration because it can filter out all the minerals and impurities out of your final water that ultrafiltration leaves for you to drink. Therefore, RO purification works better than the ultrafiltration process and is more effective in dealing with salts and other heavy metals in your water.

Reverse Osmosis Water vs. Deionized Water

What is deionized water?

DI or deionized water is also the Type II water purified by removing most of the mineral ions. These include iron, calcium, copper, iron, sulfates, and chloride.

This process uses hydrogen and hydroxyl ions for dissolving minerals and then recombining them to form water. But it is not effective in capturing small microorganisms such as bacteria or viruses.

How is RO better than deionized water?

RO systems can deal with bacteria and viruses, and they can also remove most of the impurities and contaminants from water.

Therefore, deionized water might be free from contaminants or heavy metals, but it is not as effective in getting rid of bacteria or viruses. Thus, RO systems take the lead here.

Reverse Osmosis vs. Carbon Filter

What is a carbon filter?

A single carbon filter works like the activated carbon filter that functions inside the refrigerator. Therefore, the results that it can produce will be very similar.

However, it can purify some contaminants and impurities but not all organics and inorganics. Therefore, it is not as effective as RO systems.

How is RO better than a carbon filter?

RO systems are highly effective in filtering out different impurities, organics, and inorganics. It is an effective purification system that calls out heavy metals, bacteria, and viruses. Therefore, it is a much better option than a carbon filter.

Reverse Osmosis vs. Spring Water

What is spring water?

There is a huge misconception about spring water. Many people believe that spring water is pure water, but it’s not. Springwater has many impurities that you will find in your tap water that comes from wells.

Some spring waters have higher TDS, while others have low levels. But it is rightly comparable to your regular tap water. It is sourced from underground water, called spring, and none of it is sourced from surface water.

How is RO better than spring water?

Springwater is nothing but a misleading concept, and it might not differ much from your regular unfiltered tap water. Therefore, it might have all impurities and contaminants that you should not be consuming regularly.

Therefore, the RO system is a better option because it produces practical results and removes any impurities or contaminants from your drinking water. It is not based on some marketing concepts that spring water companies manipulate people.

Final Word

Reverse Osmosis is a powerful water filtrations process that eliminates various impurities and contaminants. It is more efficient than most other filtrations and purification processes.

Only mineral and alkaline water have better results in terms of tastes, and alkaline water can take the acidity that RO process can sauce since it removes some essential minerals like magnesium and calcium.

Apart from that, Reverse Osmosis is the best water filtration process that produces clean drinking water in our faucet. Moreover, its installation is not that difficult, and you can go for different under-the-counter installation options for your kitchen in your home or at the office.

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