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reverse osmosis water filters

Water Filters: Reverse Osmosis Water Filters

Reverse Osmosis: How Reversing Nature Led to Cleaner Water

Even though most of the Earth's surface is covered with water, very little of it is safe for drinking as is. Most of the world's water is contained in the oceans as sea water. The high content of salt in sea water makes it unfit for human consumption. Drinking sea water eventually leads to death. An attempt to make sea water drinkable led to the development of a water filtration process known as reverse osmosis.

Reverse osmosis is a water filtration method that was developed in the 1970s. It was first used in desalination, the process of getting fresh water from sea water. Reverse osmosis soon appeared in the home water filtration market as a better working alternative to expensive and inefficient distillation systems.

The reverse osmosis process reverses a natural tendency of water in relation to a semi-permeable membrane. A semi-permeable membrane lets through some atoms and not others. If you have a area of water with a small amount of dissolved material on one side of a semi-permeable membrane, and water filled with a higher concentration of dissolved material on the other, water tends to move through the membrane toward the more highly-concentrated solution until the solution is equal on both sides. Reverse osmosis reverses this process so that water moves toward the weaker solution, further diluting it.

When reverse osmosis was developed to desalinate sea water, it was found that the semi-permeable membrane block other contaminants in addition to salt. After this discovery, reverse osmosis water filter systems were developed.

Since most minerals contained in water have molecules larger than the water molecules, reverse osmosis is very effective at removing mineral content from water. Minerals like salt, lead, manganese, iron and calcium are successfully filtered by reverse osmosis home water filter systems. Reverse osmosis is also able to remove some chemical contaminants, including the fluoride that is present in many municipal water systems.

Unfortunately, most municipal water systems also contain contaminants like chlorine and organic chemicals that are physically smaller than water molecules. Any contaminant that has molecules smaller than water molecules passes through the semi-permeable membrane and stays in the filtered drinking water.

Reverse osmosis water filter systems can actually make water more dangerous in some cases. If certain alkaline minerals are removed from water, then the water becomes more acidic. In an attempt to lower the acidity of the water, your body may take calcium and other minerals from your bones and teeth. Reverse osmosis also removes trace amounts of minerals from your water, leaving it tasteless.

Reverse osmosis filter systems are also very inefficient, wasting about three gallons of water for every gallon of purified water that it produces.

RO water filters can be very useful in rural areas where municipal water is unavailable, but river or sea water is plentiful. Reverse osmosis is also a very useful process in some of the world's desert areas that have almost no drinking water, but usually have an abundance of sea water.

Reverse osmosis is also useful as a step or phase of water treatment used in combination with other methods. Some home filtration systems use reverse osmosis in combination with carbon filtration and UV light treatments.


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House Water Filters, Water Filters For Home, Pure Water, Clean Drinking Water, Water Filtration Systems