Reverse osmosis (RO) is a water purification technology that uses a semipermeable membrane to remove ions, molecules, and larger particles from drinking water. In reverse osmosis, an applied pressure is used to overcome osmotic pressure, a colligative property, that is driven by chemical potential differences of the solvent, a thermodynamic parameter.
Reverse osmosis can remove many types of dissolved and suspended species from water, including bacteria, and is used in both industrial processes and the production of potable water. The result is that the solute is retained on the pressurised side of the membrane and the pure solvent is allowed to pass to the other side. To be “selective”, this membrane should not allow large molecules or ions through the pores (holes), but should allow smaller components of the solution (such as solvent molecules) to pass freely.
The process is similar to other membrane technology applications. However, key differences are found between reverse osmosis and filtration. The predominant removal mechanism in membrane filtration is straining, or size exclusion, so the process can theoretically achieve perfect efficiency regardless of parameters such as the solution’s pressure and concentration. Reverse osmosis also involves diffusion, making the process dependent on pressure, flow rate, and other conditions. Reverse osmosis is most commonly known for its use in drinking water purification from seawater, removing the salt and other effluent materials from the water molecules.
- How to Select Best Water purifier
- Cause of Water :Pollutions in India
- Best water Purifier below 2500Rs
- Best water Purifier Between 2500 to 5000 Rs Suitable for Home
- Best water Purifier Between 5000 to 1000 Rs Suitable for Home
- Best water Purifier Between 10000 to 15000 Rs Suitable for Home
- Best water Purifier Between 15000 to 25000 Rs Suitable for Home
Why RO Purifier is required
Bacteria and Viruses in water and the diseases that they cause are what worry most people and the reason why most buy a water purifier. More dangerous than the bacteria and viruses in water is the dissolved poison chemicals in water like Arsenic. These are silent killers with no symptoms for years and when health problems start showing, it is usually too late to treat it.
Of all types of home water purifiers available, only an RO water purifier can get rid of Arsenic and other poison chemicals in water. That is why we say that with an RO water purifier fitted in your kitchen, you can rest assured that you are getting safe drinking water at home.
- The RO treated water is not only pure but also great in taste and smell. This is because the RO system removes about 98% of chemicals from the tap water. So you do not have to bear with the taste and smell of chlorine anymore.
- With the removal of lead, mercury, chlorine, asbestos and other 2100 well known toxins, RO system significantly reduces the risk of illness and diseases.
- The water that you get from RO system hydrates your body at a faster pace.
- The best part about RO system is that all the pollutants are not collected but directly flushed down the drain.
- The RO system is best for areas having hard water.
- Chlorine taste and odours are also removed; your tap water will not only be safer, but also tastier;
- With an RO water filter you will save money on expensive bottled water;
- RO systems don’t use up much space and have a low energy consumption;
- Because RO water filters produce highly purified water, foods cooked with RO filtered water will have an improved taste;
- As most minerals like iron, magnesium, calcium and sodium are larger in size than water molecules, the semi-permeable prevents them from passing on to the other side. So the water actually gets de-mineralized. The removal of naturally occurring minerals not only makes the water less healthy but also affects its taste. Thus many people find the RO water tasteless.
- The RO membrane fails to remove any dissolved salts ions or particles that are smaller in size as compared to water molecules.
- It is expensive to use an RO water purifier as it runs on electricity.
- The system needs professional assistance for cleaning.
- Has a single application – producing microbiologically safe water, this means that it has no effect on chemicals, heavy metals, volatile organic compounds, sediments, hard water problems, or any other such issues;
- A pre filter is a requirement with these systems, however most UV filters (even advanced models like the Luminor Blackcomb 5.0 UV System) come without any pre or post filters. This is largely due to the fact that consumers have different types of filtration needs, and filter cartridges can vary largely depending on each particular need. When used together with these UV pre filtration systems, UV water treatment can offer a complete filtration.
UV water purifier is a water purifying filter which uses ultra-violet light to kill all germs, bacteria, protozoa, cysts, etc. in water. On the right is a picture of a cutout UV water purifier showing its internals. The arrows show the direction of flow of the water upwards and passing around the UV bulb. Water should always flow upwards in a UV filter to make sure that there are no air pockets and that the area around the UV bulb is filled with water. There should be a safety mechanism in UV water filters so that electricity does not come on, if there is no water around the UV purifier bulb. The purpose of UV water purifier is to kill the harmful microorganisms such as bacteria and viruses in drinking water while it flows around the UV lamp. With a Point of Use UV sterilizer, you will have the peace of mind that the water is properly disinfected prior to drinking.
UV water purifier works by having Ultraviolet rays penetrate the cells of bacteria and viruses destroying their ability to reproduce. Without this ability, these organisms cannot multiply and eventually die.
UV water purifiers have a simple but very effective process, with the UV water purifier light killing upto 99.99% of germs in water. The normal UV water purifer for a Point of Use drinking water purifier in the kitchen, will use about the same amount of energy as a 40 watt light bulb. It is possible to connect the UV water purifier to an inverter or UPS, so that it can be operated even when there is no electric supply. The problem with UV water purifier is that it kills the germs but its bodies remain in the water. RO water purifier purifies water by completely removing the smallest of germs and bacteris from the water.
- Cost effective, inexpensive. UV rays source bulb uses approximately 60 watts of power which quite equivalent to normally used a light bulb.
- Does not uses any chemicals. Therefore, water taste and colour unaltered.
- Gives instantly purified water. Just you have to switch on electricity supply and get purified water instantly, whereas other water purifiers take much more time to purify.
- Not removes dissolved impurities:UV water purifier kill bacteria and viruses but does not remove dissolved impurities such as pesticides, rust, arsenic, fluoride etc. Does not convert hard water to sweet, soft water.
- No water storage tank:Most of the UV water purifiers don’t have water storage tank. The user has filled water in the external bottle.
- Requires electricity:UV water purifier requires electricity to run. If in your area has frequent electricity cut off and water purifier don’t have storage tank then you don’t have any source for purified water until electricity came.
- Not effective on muddy water :UV water purifier is not effective when water contains muddy. In case muddy water, first water passes through any other purifier system then pass through the UV water purifier.
- UV light shutoff:As UV light is invisible, it’s very hard to know whether UV purifier is working or not. If UV purifier stops working and user unable to find out, results UV water purifier delivers impure water. That’s why most of the experts suggest replacing UV water purifier tube should have to replace once a year.
- UV rays does not remain in water once water is purified. In the case of UV rays miss any microorganism while purifying, that remaining microorganisms increase their population and impure the water. It is advisable to use chlorination after water purified through the UV.
UF is the abbreviation for ultra-filtration membrane, which is a similar membrane to RO membranes but with bigger pores which cannot remove dissolved salts from water. The big advantage of UF water purifiers is that it will work without electricity and completely remove all microorganisms from water including the smallest of viruses.
So a UF water purifier is the ideal water purifier for tap water in big cities, where you can be sure that you will always get good tap water without chemical contamination. This is because a UF water purifier is capable of removing from water even the smallest of germs, the viruses, but UF cannot take out dissolved solids from water.
- Works without electricity: Requires just normal pipe water pressure.
- Actually removes the germs from water: Even if the UV water purifier kills the germs in the water, their bodies remain in the water, whereas in UF water purifier all germs and viruses are physically removed from the water and flushed out to the drain when the UF water purifier is flush cleaned online.
- Can purify even cloudy turbid muddy water: UF can handle turbid or muddy water and can purify all the dirt and germs by physically removing it from the water. UV cannot purify turbid muddy water because the germs in the water will be shielded from the UV rays by the turbid dirty water particles.
- Better than boiled water: In boiled water the dirt, boiled germs and their eggs remain in the water, while Permionics UF Membranes filter out all dirt, germs and their eggs.
- No need of annual maintenance contract: A unique manual flushing system drains out all blocked germs and dirt which keeps UF Water purifiers in top condition for many years.
- Long lasting: With proper care UF water purifiers can work upto 10 years before major service by manufacturer is required.
- Filters out even eggs of Germs: Removes from water the highly Chlorine resistant eggs (cysts) of Amoebic dysentery and Gastroenteritis germs – Giardiasis and Cryptosporidiosis. Some water purifiers use very strong, harmful to human consumption chlorine chemicals, to kill the germs, but their eggs (cysts) are not destroyed. The eggs (cysts) have very hard protective shells which cannot be penetrated by chlorine chemicals. Also the dead germs and their active eggs are not filtered out of the water in these purifiers.
- As good as RO purifier: Ultrafiltration membrane water purifiers are as good as Reverse Osmosis water purifiers when used with public or Municipal supplied pipe or tap water. Piped tap water will not have problems with dissolved salts of toxic chemicals like Arsenic or Heavy Metals. RO is only required when the water has too much dissolved salts.
- Works without Electricity: UF water purifiers work even during power cuts and power outages.
- Cannot be used with water containing high TDS level or having higher no. of dissolved impurities. Since membrane pores all larger in size compared to RO membrane some smaller impurities like some salts of nitrates dissolved toxic chemicals cannot be removed from the water.
- Not Effective as compared to RO water purifiers. Because of larger pores size compared to RO membrane Heavy metals like Arsenic, Mercury and Lead cannot be removed from the water. These are harmful substances cause disabilities in Humans.
RO water purifier is the best water purifier for home use in India. The reasons are many as explained in our various pages
Why an RO water purifier is the best is because an RO water purifiers gets rid of all impurities in water, by all we mean not only all bacteria, viruses, parasites and their eggs, but also chemicals dissolved in the water. Thus you get pure almost distilled quality of water. So RO water is the safest drinking water available.
There are mainly two different types of Reverse Osmosis RO water purifiers available in India: one is an undersink RO water purifier and the other is a wall mounted RO water purifier.
Pictures of these two types of RO water purifiers are shown below. Both are storage type RO water purifiers since they have a storage tank for purified water, and purified water will be available even when there is no electric power in the house.
The best way to buy Water Purifiers in India is to first look at all models of Water Purifiers available online at the leading online Retailers in India.you will find the full range of Indian Water Purifiers complete with their best discounted price and full specifications. This is great information, and you can decide on which model of water purifier to buy. With the model of water purifier you want to buy finalized, you can go to local shops to try and find the model of water purifier you have chosen and see if you can get at similar price of that at Amazon.in. In most cases the price from Amazon will be cheaper, because they buy in bulk from the manufacturers direct and they sell huge volumes because they are the world’s largest and most trusted online retailer. If you buy from Amazon, they will arrange to have the water purifier installed in your house, usually free of charge.
Warranty and other facilities offered through Amazon are usually better than what you can get from local agents of water purifiers.