Water filters are specialized sieves used to ensure that water is clean and safe for drinking. With water being vital to the survival of humanity, the use of water filtration systems is of great importance. Unfiltered water carries with it sediment and microorganisms that may be harmful to ones health. This makes the addition of a filtration system in the home of great value.

There are different types of water filters available commercially that intend to serve the same purpose - making water safe for use. These filters use various processes such as distillation, reverse osmosis and carbon bonding.

The distillation process involves boiling the impure water until it vaporizes leaving any particles in it behind. The vapor then passes through a device that cools it back to liquid form. This process, tested in laboratories using an apparatus known as a distillation tank, has proven quite effective.

Reverse osmosis is a more complicated process. The water molecules, which are under great pressure force their way through a thin film or membrane. The membrane blocks substances in the water from seeping through. Reverse osmosis has proven effective in removing heavy metals such as lead and aluminum from water as well as microorganisms like bacteria and viruses.

Systems that use carbon in the filtration process work through adsorption. The carbon filtration process is composed of two distinct procedures, chemical bonding and mechanical straining.

In Chemical Bonding, an activated piece of black charcoal, which is hydrophorbic, is used. The black charcoal has an electro-positive charge that makes it a more attractive bonding agent to chemicals and other impurities. As water forces its way through the carbon, it passes slowly to allow sufficient contact time. This enables sediment in the water to attach to the carbon.

The second method of water purification using carbon is mechanical straining; carbon compressed into a solid block is used. Water molecules strain through the carbon blocks microscopic pores and effectively eliminate any particles. This method is more effective in removing a larger number of contaminants than chemical bonding because it has larger surface area of carbon.

The degree of effectiveness will depend on the flow rate of water and the contact time with the carbon. If the flow rate is too high, the filtration could have zero efficiency. These carbon filtration methods are more efficient in removing sediment, chlorine, and organic compounds from water. They are not as effective in removing dissolved inorganic compounds, minerals or salts.

These filtration systems have all proven to eliminate harmful organisms from water to a certain extent. Although water filter manufacturers claim that their products eliminate all impurities in water, the truth is that no filter is 100 percent effective. Human error as well as malfunction of the filtration system is possible.

When purchasing water filters, it is important to take note of the filtration process they use. Most people prefer those that incorporate distillation while others prefer a combination of several processes. Water filters are effective means of purifying water.