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Does Reverse Osmosis Remove Salt from Seawater to Make it Drinkable? 

Does Reverse Osmosis Remove Salt from Seawater


Does reverse osmosis remove salt from seawater? Yes, Semipermeable membranes allow feed water to pass through at a significantly higher volume than dissolved salts.

You might wonder how to remove salt from water if you have an ion-exchange water softening system. You can use water filters that remove sodium. This article will describe the procedure for removing salt and other contaminants from seawater. You will also learn the exciting benefits of RO water filters.

What’s that? According to Wikipedia, roughly 16,000 distillation factories are in operation in 177 countries. Because distillation and RO systems remove salt from seawater, individuals use these treated waters in their houses. 

Let’s learn how reverse osmosis makes salty seawater drinkable.

Why is the Sea Salty? 

The two sea salt bases are runoff from the land and slots in the seafloor.

According to National Ocean Service:
“The majority of the salt that dissolves in seawater comes from rocks on the ground. Because rainwater is slightly acidic when it falls on land, it erodes rocks. It causes ions to be released, which are carried away by streams and rivers and eventually end up in the ocean. “
Another source of salts in the ocean is hydrothermal fluid, which emerges from vents in the bottom. The Earth’s core magma heats the oceans. Heat triggers a variety of chemical reactions. 
Hot water contains many dissolved metals when it falls from vents into oceans. Some ocean salts are composed of undersea volcanic eruptions that release minerals directly into the sea.

What is Seawater Desalination? 

According to San Diego Country Water Authority:
“Reverse osmosis technology is designed to separate water molecules from seawater. Under intense pressure, seawater passes through thousands of tightly coiled semipermeable membranes.
The membranes let smaller water molecules cross the barrier, leaving salt and other contaminants behind.”
There are the following steps in the seawater desalination process. The Big desalination plants mostly follow these steps. Filters eliminate particulates and suspended materials that might block the desalination process.

Reverse Osmosis: Brine releases as leftover high-salinity water. Membranes used in reverse osmosis extract dissolved minerals (such as salts) and other contaminants from water.

Conditioning: We need to add minerals and chemicals to make water fit according to aesthetic and anti-corrosion criteria.

Reverse osmosis water is transferred to water supplies and your homes as tap water.

Does Reverse Osmosis Remove Salt From Seawater? 

There are a variety of methods to remove salt from water. Reverse osmosis is one of them. Its chief role is to desalinate water. Water passes through small filters via RO membranes, which remove the salt.
Separating pure water from seawater and brackish waters is an actual application of reverse osmosis. Seawater or salty water pumps against one surface of the membrane. It causes salt-depleted water to transport across the membrane and emerge as potable drinking water.

RO can remove 99 percent or more dissolved salts (ions), particles, colloids, organics, microorganisms, and pyrogens from the feed water. However, a reverse osmosis system should be kept from removing 100 percent bacteria and viruses.

For seawater desalination, RO is a frequently used membrane method. The central premise of Sea Water Reverse Osmosis (SWRO) is to use a semi-permeable membrane. It rejects the majority of dissolved species while allowing water to pass through.

How To Remove Salt From Water Naturally?

Some people require minimal sodium in their diets or prefer the sodium eliminated from their drinking water. You’ll need to know how to remove salinity from water if you want to attain the benefits of softened water.

Reverse osmosis water filters, in particular, can eliminate salt and a range of other impurities from softened water.

RO is a highly effective and natural approach for eliminating sodium from softened water. RO systems, on the other hand, drastically reduce the number of pollutants in water.

Let’s look more closely at reverse osmosis systems, which provide a natural way to remove salt from water.

Ways To Remove Salt From Water 

Biological filtration is the most famous and efficient strategy for removing salt from water. Reverse osmosis systems, in specific, may purify salt and a broad range of other contaminants from softened water.

Reverse Osmosis 

Reverse osmosis is a method that uses pressure to force water through a semipermeable membrane to remove the vast majority of pollutants from water.

The following pollutants in tap water can be removed or reduced by reverse osmosis: protozoa like Giardia and Cryptosporidium.

Potassium Chloride 

Potassium chloride has established itself as a prominent reagent for water softeners. It is kinder to the environment than sodium chloride. Also, it increases the amount of healthy potassium in the home drinking water.

The similarities between salt-based and potassium chloride water softeners are almost uncanny. Ion exchange is at work for both of them. The two minerals that make up hard water, calcium, and magnesium, are positively charged.


Water is converted into vapor during the boiling process, leaving behind salt. Salt is then gathered and condensed back into the water after being cooled. Reverse osmosis is the most typical kind of membrane separation. 

The salt will remain as a solid after boiling or evaporating the water. Utilizing distillation will allow you to gather the water. It works since salt has a boiling point that is substantially higher than water.


Electrodialysis is a process of transferring salt ions from one solution to another. The process requires ion-exchange membranes and an applied electric potential difference. For this setup, you can use an electrodialysis cell.

Electrodialysis employs ion exchange membranes that move ions from aqueous solutions. Like reverse osmosis, electrolysis removes ionic pollutants from water.

Benefits Of Treating Seawater 

We know that shortage of water is a global problem. Too many people are suffering from this issue. According to research: There are 35 desalination plants in Dubai for treating seawater for their daily use. You can imagine how beneficial it is to treat seawater. There are several benefits of treating seawater.

  1. Treating seawater provides people with Portable reverse osmosis water.
  2. It helps agricultural industries by providing salt-free water.
  3. Water quality is safe because RO removes excess sodium from water which is hazardous to living things. 
  4. It uses tried-and-tested technology. The method is proven and practical.
  5. It aids in the preservation of current freshwater supplies.
  6. People use reverse osmosis desalination systems to remove salt from the well water.  Now, this water is helpful to home plants and increases plant life.


Some other questions, and answers for our readers that might be helpful for reading.

How to Remove Salt from Water Softener?

One of the most significant ways to take sodium out of softened water is with a reverse osmosis system.
A semipermeable membrane uses reverse osmosis to filter out all total dissolved particles. Thus, Sodium and mineral ions filter out, leaving only clean water behind. Even large-scale implementations of this method to desalinate saltwater employ it.
Reverse osmosis systems are installed after water softening systems so that your drinking water:

Be made softer

Be filtered, taking off all the salt that is harmful to health.

How to Remove Salt from Water Without Heat?

You can achieve it by reverse osmosis. 
Desalination by heating is the most traditional method of converting saltwater to freshwater. Most desalination plants use reverse osmosis because it is a new method that is significantly more affordable than other desalination methods.
By forcing water across a membrane, reverse osmosis employs pressure to filter it. Chemicals, nutrients, bacteria, viruses, and salt are all taken out of the water by the membrane. With the help of these membranes, you can convert saltwater into potable water.


For many industrial applications that call for demineralized or deionized water, reverse osmosis is a reliable and efficient method. Additional post-treatment after the RO system, like mixed bed deionization, can improve the quality of the RO water. Hence, the water became appropriate for the most demanding applications. An RO system must be properly pretreated and monitored to avoid expensive repairs and unforeseen maintenance. Your RO system should deliver high-purity water for many years with the right design. Its maintenance schedule and knowledgeable service assistance are also worth considering.

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