RO and RO Membranes
Updated: Mar 24, 2022
Reverse Osmosis (RO) water treatment systems are the preferred choice of most modern industries today – and there is a reason for it. The purification process and the levels of hygiene ensured by it are far superior to any other mechanism. This is especially true for the contaminated, polluted water bodies in today’s consumer-driven world.
How then, does the water become magically cleaned of most of its pollutants in the RO process? Let’s get a sneak peek into the lifecycle of RO-processed water, and the ‘hero’ of the process – the RO membrane.
What is Reverse Osmosis?
In layperson terms, osmosis is the process by which particles pass through a membrane from a low-concentration liquid to a higher concentrated one. However, in the case of contaminated or challenging water, we need a mechanism to force the higher concentrated liquid with impurities through a membrane. Using pressure to achieve this is the process of reverse osmosis.
Thus, RO is the method of using a semipermeable membrane to achieve the highest quality of filtered liquid. The semi-permeable RO membrane filters out all inorganic and most organic elements in the water, leaving the water purified and safe for all purposes.
Does RO remove all contaminants?
Reverse osmosis has become the universal choice of water purification, across industries and homes, because of its powerful filtration ability.
It successfully eliminates most dissolved salts over 95-99 percent. An RO system leverages sophisticated technology ensuring the highest levels of filtration, effectively filtering out all kinds of contaminants.
What is an RO membrane?
The fascinating process of pushing liquid at great force through a semi-permeable membrane is possible due to its unique composition, that needs to be porous and yet withstand great pressure.
The RO membrane is actually made up of multiple thin composite membranes, including an extremely fine polyamide layer that allows everything but salts and particles to pass through. A separate porous sheet of polysulphone in the middle and a third polyester support web ensure extreme filtration. The collective membrane sheet is wound around a perforated collection tube.
When water is passed at high pressure through this membrane, some of it is pushed through, filtered, and flows out through the tube. The remaining unfiltered water flows away from the outer surface of the membrane.
The sizes of RO membranes vary according to the desired end-use – increasing in high volume industrial use cases. Customized RO providers will ensure that the design is suited to your particular volumes and frequency of use.
What are the types of membranes for water treatment?
Beautiful science supports the water treatment process, with a specific type of membrane to address each filtration requirement - probably why RO remains so effective across a range of applications to filter out the smallest of contaminants.
The types of membranes include:
· Microfiltration (MF) – They have larger pores and are used to filter out larger particles and organisms.
· Ultrafiltration (UF) – They have smaller pores and can trap macromolecules like proteins, and bacteria.
· Nanofiltration (NF) – They have such tiny pores that although they can pass liquid, they still filter out divalent ions and most micro-organisms.
· Reverse osmosis (RO) – These are non-porous and screen out even micro-particles, salts and ions.
Popular RO membrane manufacturers
The level of water filtration depends on the quality of the membranes – the size, the layers and the stringent testing. The effectiveness of any water purifying instrument is based on the excellence of the membrane quality. Advanced Watertek partners with the preferred RO membrane manufacturers today that include DuPont Water Solutions (US), Toray Industries (Japan), and Hydranautics (US).