Home water purifiers; Know the filters inside

Home water purifiers, which one to choose? Know the filters inside

Water purification could take place at three places, the place of production, the point of entry to house and the point of use. Municipality takes care of purification at the point of production. If you are using water from well or river directly, a point of entry whole house filter would be ideal. When you are using water supplied by government you need not worry about chemical or biological contamination. The only area you need to consider is the point of use.

This section mainly discusses the point of use (POU) purifiers. But before we discuss water filters, let us consider one basic question.

Why you should buy a home water purifier?

1.     Cheaper

·          A small family in UAE spends AED 2500 for buying large bottles; cost is more when we buy smaller bottles

·         Empty bottles occupy three to five square meters of office / house space costing a minimum of AED 5000 in annual rent.

2.     Convenient

·         No need to wait for the sales men

·         No need to lift heavy water bottle

·         A purifier gives non-stop water supply

·         The machine in your kitchen is more reliable than one sits several miles away

3.     Earth friendly

·         No wastage of empty bottles

·         No transportation cost

Now, let’s come back to the main issue. One purifying machine could contain different filters inside. People mainly go for bottled water because they do not know that the home filters can do the job better. If you go to buy a water purifier without gathering enough information, you could either waste a lot of money for features which you do not require or buy something that does not solve your problem. The worst part is that you could continue to use bottled water.

Filter size: If you read the sticker on a filter, you would notice the pre size of filter. Smaller size is better. A filter pore size is often mentioned in terms of micron. One micron is 1/1000,000^th of a metre. In other words 1000 micron is one millimeter. A diameter of a human hair is approximately 100 micron. Any filter with pore size around 5 microns or below can give you clean looking water, but most of the microorganisms pass through the filter.

Following are the common filter types:

1.     Sediment filters: Sediment filters, as mentioned above, are only meant for removing larger suspended particles from water. These filters are pre-treatment filters. Sediment filters are usually made of polymer, cloth like material. PP filter means Poly Poplin (textile) filter. They have pore size around 5 microns. Remember, 5 micron filters are only pre treatment filters. They are useful inside a purifier. Never use a sediment filter as a stand-alone unit.

2.     Activated Carbon Filters: Carbon is very effective in removing most impurities from water including chlorine. Carbon is activated by passing oxidizing gases at very high temperature to create pores in the carbon which substantially increases the surface area to trap impurities. Surface area of one pound of activated carbon is said to range from 50 to 150 acres which makes it very powerful in capturing the impurities. Activated carbon stops impurities in two ways. First it does not allow particles above the pore size to pass through. Secondly, it traps chlorine and other contaminants inside the pores. There are two types of activated carbon:

·         Granular Activated Carbon (GAC) Filters: GAC Filters made by packing lose carbon granules to allow the water to pass through it. GAC filters allow faster water flow. But they are less effective compared to Solid Block Filters.

·         Solid Block Activated (SBAC) Carbon: As the name indicates carbon is bonded together to form a single solid block. Solid block filters provide larger surface area compared to GAC filters. Smaller pore size of SBAC filters allow better filtering.

Carbon filters do not remove fluoride and arsenic. Only reverse osmosis is effective where these contaminants are present.

3.     Reverse Osmosis (RO) Filters: Osmosis is the process by which plants roots absorb water from surrounding soil. When liquids of two densities are separated by a semi permeable membrane the high density liquid will absorb a low density liquid. In reverse osmosis filters, this process is altered by applying pressure on the high density side. To put it simply, contaminated water is fed in using a pressure pump in to one chamber. RO membrane does not allow impurities to pass through. About one fourth of the water comes out clean through the RO filter. The remaining rejected water goes out though the outlet valve.

See the diagram below:

Reverse Osmosis the possibly the most effective way of water purification. It can remove bacteria, virus and dissolved salts. RO is the only filter which can produce fresh water from sea water.

The main disadvantage of RO filter is the water rejection. The maximum output of clean water is only twenty five percent of the input water. It is does not matter when you are filtering sea water. But when water availability is scarce, you cannot afford to waste that much water. Another issue is the need of electricity. There is a small electric pump to apply pressure on the input water. The filter cannot be used where electricity is not available. RO filter require regular maintenance. Excessive chemicals damage the filter. Good pre-filtering is essential to minimize chemical concentration of input water.

4.     UV Filters

Ultra Violet (UV) light stops the reproduction of bacteria and viruses. These filters are effective only against microorganisms. They do not remove other impurities. We cannot use it as stand-alone unit. However it is very useful in combination with other filters such as carbon or polymer filters.

Apart from the above basic purification methods there are several other technologies used independently or in combination with the above.

What are the possible impurities in drinking water?

Purity of drinking water mainly depends on the source of water and methods of handling it. If you have municipal water connection, there is a reasonable assurance of quality of water. As far as possible government agencies will supply only pure water to the people. In UAE, especially in Abu Dhabi and Dubai every house is connected to municipal line. Pure distilled water which comes as a by-product of power generation is distributed almost freely to the public. There is almost no chance of biological contamination in this water. There is a remote possibility of lead contamination or other impurities from old water tanks or pipe fittings in the house. Chlorine is added to water to prevent the growth of bacteria or other biological contaminants during the distribution stage. Chlorine by-products increase the risk of certain cancers if contaminated water is consumed over a period of 20 of 30 years.

In UAE you chances of biological contamination are very less. However, contamination from chemicals is possible. A good quality filter is capable of minimizing the risk of both biological and chemical contamination. Biological contaminants cause concern mainly where water comes from wells or rivers.

1.     Lead or other contamination from pipe fittings: Contamination from water tanks or pipe fittings is a serious health risk. You cannot notice lead contamination by simple observation. Water could look clear and taste normal. But if the pipe fittings are old there is possibility of contamination. The best solution is to use a good water filter.

2.     Chlorine: Chlorine is not a very serious health threat, though bottled water companies blame it for every known disease under the sun. However if chlorine reacts with other organic materials it could produce harmful substances commonly called disinfection by-products (DBPs). If you pour the water into a container and keep it for some time, most of the chlorine will just disappear. Chlorine causes poor taste of water. A good filter will help you avoid all such problems.

3.     Protozoans: These are one celled organisms in dormant cyst stage. They are resistant to chlorine treatment. They are found universally in surface water. They cause gastrointestinal disease.

4.     Bacteria: They are responsible for diseases such as cholera (caused by vibrio cholera) and typhoid (caused by Salmonella typhi). E-coli is another common bacteria entering water supply from human or animal waste. Chlorination of water is an effective method of killing bacteria.

5.     Virus: Viruses are the smallest of all the microorganisms. They are responsible for several diseases. Chlorine can kill most viruses.

(Different filters, their functions and limitations are discussed in another article. Pl. check the index)

Visit://http://www.water4uae.com

My water pollutes Our earth; the question of ethics

 Plastic is a wonder product, very versatile and convenient as long as we use it carefully. But when we are careless, plastic will become the biggest problem for our children to handle. While most biological trash we throw disintegrate in a matter of days or months, plastic will remain for hundreds of years. Imagine how many generations will suffer for a little convenience we enjoy today. When we drink just one litre of bottled water a day we are throwing out over 60 dirty bottles a month; and now consider what happens if everybody choose to drink bottled water? Our earth will become a plastic dump yard in no time. It is very easy to litter but difficult to keep the place tidy. 

Unfortunately our ignorance or lack of concern is trashing the planet and trashing each other. Bottled water is a big business. The cost of water is almost nothing. They are just filtering the free water using a process which almost cost nothing, fill it in plastic bottles and sell at 2000 times the original cost. Can you imagine any business as profitable? No wonder bottled water business has become a universal bush fire in less than 20 years. People in US buy almost half a billion bottles of water every week; that is enough to circle the globe more than five times. Clever advertisement simply creates demand for what we actually do not need. It is called ‘manufactured demand’.

How did bottled water business come in to existence in such a short time? During the 1970s large soft drink companies found that that their sale is not increasing any more. You can’t convince people to drink too much carbonated drink. So they found out the next big idea of selling water. Few people thought there is business in selling water which is distributed free of charge. Normal people will not spend money on an unnecessary product. Advertisements telling people the tap water is not safe to drink finally tilted the minds of sizable number of people to believe the lies. That was the beginning of bottled water story.

How can we fight back this giant menace? There are hundreds of different water filters available in the market today. Buy one that suits your preference and budget. Carry a small steel water flask in your bag. You can fill water wherever it is possible. Remember, water bottle is a pest. Stop feeding it.

RO Filters - What is Inside?

This is an RO filter that is connected directly to the home water supply line. Filters are very neatly placed inside the compact cabin. It also comes with UV sterilizer to guarantee peace of mind.

Bottled Water is Just Tap Water

Many people think bottled water is the purest water. The fact is just the opposite. Most of the bottled water is just filtered tap water and we pay 1000 times the normal price of tap water.  This is the price of supposed convenience. The so called convenience is just temporary. Plastic bottles are now a serious environmental menace.

Water making machine is one solution. Initial price of $1000 is bit discouraging. A viable alternative is RO filters. Compact Reverse Osmosis (RO) filters with UV radiation provide the best drinking water.  A good machine costs only around $100.

Ecoloblue Water Generator Video

More about Water from Air in UAE

This machine uses more advaned technology than the one I brought. it produces 28 literes. It costs $1200 in UAE. Water from this machine costs just 7 fils per liter for electricity. No more waiting for the water delivery man, no more lifting of heavy water bottle. It is never ending source of pure, fresh water hot or cold as you choose. A basic unit producing 20 - 30 liters is more than sufficient for daily drinking water needs of small families. Larger units costing $1800 produces 138 liters per day.

There are five stage filtering which include three carbon filters, one RO system and finally UV lamp ensuring best drinking water for you.


For details please call:
Sam 00971(0)55 -5924231