Lately, RO (Reverse Osmosis) has become a byword for water purification. Originally used in industrial applications and laboratories, RO has proven to be a breakthrough technology that helps in the purification of water and producing water that is almost as pure as distilled water. Before we learn about the technique and its pros and cons, let us understand what osmosis is.
What is Osmosis?
Osmosis is a naturally occurring process in which the solvent moves across a selectively permeable membrane from a solution with a lower solute concentration to a solution with a higher solute concentration until an equilibrium is reached where the concentrations of the solute are the same on both sides of the membrane. It is through this biological process that plants are able to draw water from the soil through their roots.
What is Reverse Osmosis?
Reverse Osmosis, as the name suggests, works in a direction opposite to osmosis. Here, by the application of pressure, the solvent moves from a solution with a higher concentration to a solution with a lower concentration. The solution with a higher concentration is nothing but the water with all its dissolved solids, metallic residues, pathogens, organic and inorganic matter. The solvent (water) from the solution overcomes the osmotic pressure and moves across the membrane, leaving behind the solute (impurities) on the other side of the membrane.
The semipermeable membrane has extremely tiny pores whose diameter is in the order of 0.001 microns and can filter out most of the contaminants including protozoa, viruses, bacteria, minerals, dissolved solids, metallic residues, etc., resulting in an output of nearly 100% pure water. Since the pore size is in the order of nanometers, it is also called nanofiltration.
Is it a must for every household to get an RO filter?
To understand your specific needs, you must first know what TDS is. TDS is nothing but the Total Dissolved Solids quotient of the water. According to a popular research body, TDS in drinking-water originate from natural sources, sewage, urban run-off, industrial wastewater, and chemicals used in the water treatment process, and the nature of the piping or hardware used to convey the water, i.e., the plumbing. Water being a universal solvent, dissolves particulates and pathogens from all the things it comes in contact with.
The BIS (Bureau of Indian Standards) has recommended that every household which has a running water supply with TDS (Total Dissolved Solids) greater than 500 ppm should ideally get a RO purifier. If the TDS of your water supply is around in the range of 1-200 ppm, it is ideal for consumption and all you need to do is get a basic water purifier. In this case, a gravity-based water purifier will do the job. As long as the TDS is in the range of 500 – 2000 ppm, an RO water purification system is recommended. If the TDS exceeds 2000 ppm, no home water filtration system will be able to help you.
The pros and cons of Reverse Osmosis water purification systems
The pros of Reverse Osmosis purification
- With RO, you will be able to consume clean and safe drinking water free from pathogens, metallic ions, and chemical pollutants. Water-borne diseases would have created outbreaks by now without good water purification systems like RO.
- Residues of metals like Arsenic, Mercury, Aluminium, and Lead are not broken down in the digestion process and tend to get accumulated in the human body. Over the years, this could cause serious ailments and disorders. For instance, Arsenic is carcinogenic and can lead to various types of cancer. Similarly, Aluminium is linked to Alzheimer’s disease, liver disease, learning disabilities in children.
- Having a steady supply of RO water at home encourages drinking good amounts of water and reaping all the benefits of hydration. Drinking pure water is also linked to weight reduction through increased metabolism.
- Having access to clean and safe RO purified water reduces reliance on mineral water bottles. Though mineral water has good mineral content that is readily absorbed by the human body, it is priced exorbitantly and must be the go-to product only when you are traveling or on the move or when you forgot to carry your water bottle from your home. Over and above the price, mineral water bottles are made of non-biodegradable plastic that adds to the existing woes of environmental degradation.
For more in-depth analysis, check why you need Reverse Osmosis water purifier.
The cons of Reverse Osmosis purification
- The reverse osmosis technique wastes a lot of water which it releases through a drain pipe attached to the purifier unit. Most RO purifier units in the market save 2.5 glasses of water for every glass of water they purify. However, if you opt for quality products like HUL’s Pureit, you will be able to take advantage of the Eco Recovery Technology that saves up to 80 glasses of water per day.
Moreover, you don’t actually need to waste all the water that is released as a byproduct of RO purification. You can repurpose the water for cleaning your vehicle, gardening, and other chores that don’t need pure water.
- Since RO removes approximately 95% of the TDS, the water dispensed from the unit is free from minerals along with being free from other pollutants. Remember what BIS said about safe levels of TDS in the water? TDS up to 200 ppm is actually ideal for consumption as it has good amounts of naturally occurring minerals in the water. Thanks to technology advancements like mineralizer cartridges and TDS controllers, the water dispensed from the purifier can be remineralized with pure ions of metals like Copper, Calcium, and Magnesium, which are all required in trace quantities for optimal functioning of the human body. This also ensures that the water is not bland to taste.
- RO does not eliminate 100% of the microbes in water, as some of these nasty things can evade even nanofiltration techniques. However, if you use RO in conjunction with other filtration mechanisms like UV (Ultraviolet) technique, this problem is also solved. In the UV technique, a UV source is used whose rays are passed over the water and attack the genetic code of the bacteria, protozoa, and viruses, thus deactivating them for good.
You can check Pureit’s range of RO water purifiers when you shop for an RO water purifier.