What Does Purified By Reverse Osmosis Mean?

Purified By Reverse Osmosis

You may have read it on the label of your favorite bottled water company or you have heard the slogan in a TV commercial: “Purified by reverse osmosis” – but what does this actually mean?

Reverse osmosis is a technology that can be used to purify water. Not only that, it is also the most common and most cost-effective technology for water purification. You can even filter sea or brackish water and make it drinkable and safe for human consumption.

How Does Reverse Osmosis Work?

Filtering sea water and making it drinkable sounds like all our water scarcity problems are solved…

Sadly, it’s not as simple as that. But before we dive deeper into the problems that this technology bears, we should take a closer look at how the ro filtration process works.

(Reverse) Osmosis

The easiest way to explain reverse osmosis is to start by first explaining osmosis. Osmosis is the naturally occurring movement of liquid molecules through a semipermeable membrane (meaning only certain substances can pass through) into an area of a higher solute concentration. The movement stops once the two solutions on either side of the membrane are equally concentrated.

If we have 2 salt water solutions (A and B) separated by a semipermeable membrane and there is more salt dissolved in solution A than in solution B, water molecules will pass through the membrane from solution B to A until both have the same concentration of dissolved salt.

Reverse osmosis or “ro” describes the movement of water molecules (or other liquid molecules) through the semipermeable membrane in the opposite direction; in our case from solution A to solution B. Why? Because external pressure is applied (on side A). This pressure does not need to be very high. In most cases, the pressure present in a residential water system is sufficient.

Technological Problems

A residential point-of-use reverse osmosis system utilizes water pressure to purify the water itself. It does not need an additional power source. You can install a reverse osmosis system in your home and enjoy purified drinking water and you don’t even have to pay for extra energy expenses? Correct.

But here comes the downside: The filtration process wastes a lot of water. 6-8 gallons of water are wasted on average for 1 gallon of filtered water. Of course this drives up water costs significantly.

But not only that, a semipermeable membrane does not differentiate between harmful pollutants and health beneficial trace elements that water contains. So not only pesticides, pharmaceuticals and bacteria are removed, but also iron, calcium, selenium and magnesium, which are important for the human organism.

Visit www.best-osmosis-systems.com for more info.

Benefits and Drawbacks

Reverse osmosis water filtration offers a lot of benefits. You can purify all sorts of contaminated water making it potable. The technology is no rocket science and you don’t even need extra energy to put a residential ro system to work. Severe drawbacks are that an ro system wastes a lot of water in the treatment process and also removes beneficial solutes.