How Does Reverse Osmosis Work to Purify Water?

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In underdeveloped countries, 90% of diseases are caused by water and account for 80% of deaths. Do you know the finest filtration techniques used in the world today?

The water in the human body contains minerals and toxins. Humans have three vital organs that need to remain clean and pure. Water quality affects our kidneys, liver, and skin.

Clean water has to be filtered through a process that removes these impurities, and the answer to these problems is reverse osmosis. Reverse osmosis is also known as hyperfiltration.


What is the reverse osmosis process?

What is the reverse osmosis process?

Reverse osmosis is a popular method of water treatment. For purifying water. The membrane used to perform this filtration consists of fine holes that are only as big as a single water molecule. The larger molecules cannot pass through these holes because they are too big.

In reverse osmosis, the pressure applied to water is about ten times the typical home water supply pressure. The pressure forces water through the membrane so that it can be purified.

This process is used as a second step after water softening or demineralization to produce water with lower mineral content. It also makes large volumes of concentrated brine for reuse in the process.

This process or filtering device uses pressure and a semi-permeable membrane to filter dissolved solids from a liquid—the solids left behind (the brine). The process can produce potable water for drinking, cooking, and washing or purifying wastewater. This occurs because the water molecules are too small to pass through the membrane. The pressure of the solution must be greater than the pressure of the key on the opposite side of the membrane. The pressure differential propels the process.


The Brine

The Brine

The most critical factor in the process is that the brine formed in the reverse osmosis process must be reused for the method to be effective. In the case of the brine from the reverse osmosis system, it must be pumped back to the system for reuse. If the brine is not pumped back, it will contaminate the incoming water supply.

The brine volume is approximately equal to the importance of raw water entering the reverse osmosis system. For this reason, the system must have sufficient capacity to allow for the volume of brine produced.

The role of the brine is to act as a sink for the filtered water, taking up any minerals and other impurities. This means that a lot of water is lost in the process, so the volume of water after treatment is less than the volume before treatment.


Role of thermal energy

The process of water purification in reverse osmosis is achieved through energy, which is a form of heat. Thermal energy is used in reverse osmosis to boil the incoming brine to concentrate and make it potable. The brine is typically boiled for 15 minutes.

The reverse-osmosis water treatment process uses heat also to remove the dissolved solids from the water. This is necessary to remove the dissolved compounds from the water harmful to the human body. Typically boiled in the water treatment process, the brine is not used in reverse osmosis.

The brine solution is reused to make the process more effective. Also, the brine is not reused in the reverse-osmosis process because it is considered harmful to the surrounding plants.


How can you improve the osmosis process?

How can you improve the osmosis process?

The membrane can prevent the back diffusion of water molecules through the membrane, which is critical to reverse osmosis’s effectiveness.

It is the process by which water molecules are prevented from leaking out the other side of the membrane that makes the process effective. There are a few strategies to optimize the reverse osmosis process.

If the water is pure enough, nothing needs to be done. If the water is not pure enough, a few simple steps can help make the water cleaner.

  • First, you need to set your water purifier’s operating pressure at a higher level. Follow the manufacturer’s instructions to accomplish this.
  • The reverse osmosis process can be improved by using different filtration membranes, such as thin-film composite membranes and ceramic membranes.
  • By using a membrane with a smaller pore size, which uses less energy, and by replacing the conventional osmosis membranes.


As we advance:

Reverse osmosis is an affordable and sustainable solution to the water purification problem. With more advanced and precise membranes evolving every day, it has become necessary today.

The most recent National Sample Survey (NSS) report says, almost one-fifth of urban households in India utilize electric water purifiers, including ROs, for cleaning drinking water. You can improve the life span of RO filters by taking simple yet effective steps and enhancing performance.



1. What variables should be taken into account while making a purchase of an RO purifier?

  • You must conduct a water quality test.
  • Water purifiers should remove specific contaminants, and filters should be changed regularly.
  • Consider the cost of filter replacement.


2. Why are UV filters ineffective in protecting you?

A UV water filtration system only kills bacteria and viruses, but it doesn’t remove dangerous chemicals or dissolved particles from your water. Only Reverse Osmosis purification technology can ensure that your drinking water is completely purified.


3. When should your filter cartridges be replaced? 

Depending on the model, the filtering mechanism is different, and brand, capacity ranges from 1000 liters to 6000 liters or more. Filter cartridges need to be replaced after every 6 months.


4. What is the energy consumption of a water purifier?

The most significant source of electricity usage is when the dispenser’s boiler heats up, which can require up to 480W. In addition, the cleaner uses a modest amount of electricity to turn on the lights (less than 1W).


You May Also Like To Read:

The Difference Between RO, UV, and UF Water Purifiers

Water Filter Vs. Water Purifier: What Is The Difference?

Which Water Purifier Is Best For Health?

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