Reverse Osmosis

By: Water Filter  05/12/2011
Keywords: Water Filters, water filtration, Pure Water

Reverse Osmosis water filtration produces pure water. In this article we call it Reverse Osmosis for short. Ordinary filtration produces safe clean water that contains minerals and elements etc. The basic difference in water filtration is of course the size of the pores or holes in the filter itself. This means that the filter will stop particles that are any larger than it own pores.

Just to give you a better idea of this, a full stop on this page is about 50 microns in size. Commonly used water filters for municipal water are say 5 microns, one micron and less than one micron. A micron is one millionth of a meter and a nano-meter is one billionth of a meter. So ordinary filters give micro-filtration and Reverse Osmosis membranes give nano-filtration or ultra-filtration. Therefore we get safe clean water with ordinary filters and we get pure water with Reverse Osmosis filtration.

In a 2-stage filtration system say we use a 5micron filter and a 1micron filter. We put the 5micron filter before the 1micron because the 1micron is the size at which we need to stop particles getting through. Otherwise the 1micron filter would get clogged up faster. Pre-filters are therefore always protecting the final filter, letting it last longer and work more efficiently. The water that comes out of the final filter is the result of the whole system no matter how many stages there are.

The same principle applies to Reverse Osmosis systems, all the filters in line before the RO membrane are protecting it. The Reverse Osmosis membrane itself requires pressure to push the water through it. That is why we install a pumped Reverse Osmosis system if your water mains pressure is low.

Also with Reverse Osmosis systems there is a constant flow of water passing over the membrane to wash it and this flows to the waste pipe. The approximate result is that for every litre of pure water you get, two litres are used for cleaning the membrane. This is acceptable because not a lot of water is used anyway for drinking compared to flushing toilets, having baths or showers, washing clothes, cars etc.

In practice say we install a basic 3-stage system comprising a 5micron, a .9micron and a chlorine filter. This 3-stage filtration unit will produce safe, clean, delicious tasting water. Now if we just add the Reverse Osmosis membrane after that we get pure water. It is as simple as that.

So why bother with Reverse Osmosis filtration when less will do? Some people prefer the taste. Others need pure water for medical or scientific use. Also in your house it will remove lime-scale and continue to prevent it forming in your kettle and other utensils. There will be no scum caused by lime on your tea or coffee and fruit drinks will also taste better. Of course also there is a higher degree of filtration of the water.

There are many pros and cons for every situation that we cannot cover here but we hope that this article is helpful to you. Hope you now have a better understanding of water filtration and which system you may choose. It is not easy for an ordinary person to install the units and that is why we install them anywhere in Ireland. Give us a call on….

Keywords: Pure Water, Water Filters, water filtration

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Brief History

So when the water tap is turned on in the home for that special pot of tea or coffee, or for the invigorating hot tub or shower, and the great valves are opened in industrial establishments or to recharge swimming pools, the water must come from nearby rivers, lakes, or wells tapping the aquifers. The surface freshwater is recharged with rain and other precipitation, but because of the great depth of some aquifers, they cannot be recharged.


Some Figures

A single toilet flush is more than most people in developing counties use for drinking washing and cooking in one day. 150 gallons of water are used in the growing/prodution of a loaf of bread. At least 250 gallons of water are needed to produce one ream of paper. 1 in every 6 people in the world lack access to safe drinking water. When you use the toilet you use: 9 litres. When you use the washing machine you use.


Where is the Pure Water

Tap water is now treated purposely with several well-known chemicals (Chlorine, Flourine, lime, copper sulfate, aluminum sulfate, sulfur dioxide), and infected by accident with hundreds more. Road salt, agricultural chemicals, fertilizers, pesticides, rubber, motor oil, paint thinner, it’s just a matter of time before these pollutants make their way into the water sources.