How Do Water Filters Work? Learn the Different Types of Filtration Technologies

Our water supply system is seriously overloaded with chlorine, bacteria, fluoride, pharmaceuticals and other toxic substances. It is in fact a hazard to our health. Most of us are aware of this now whether it is from advertising, word of mouth or simply by the fact that we’ve noticed the taste, look and awful smell.  A good filter has become a necessity in our homes. Have you ever wondered though how a water filter works?

There are actually several ways that filtration works. Some filters will combine different technologies while others will rely solely on one key technology. The more technologies used, the cleaner the water will be and the safer it will be to drink. Below is a list and an explanation of the different types of filtration and how they work.

Carbon Filtration

This is when water passes through an activated carbon filter cartridge. The carbon will absorb bad odors and flavors. It will also safely absorb chlorine, sulfide, radon, hydrogen, volatile organic compounds, pesticides, benzene. Unfortunately though it will not remove heavy metals. For this reason it works great when used in combination with another filtration method.

Ion Exchange

With ion exchange h2o passes through a layer of resin beads that have sodium exchange coating. Ions  are then exchanged for ions on the beads. This method is used to soften the water by removing metals and minerals. It will remove nitrate, fluoride, sulfate, iron, calcium, magnesium and manganese. It does not however effectively remove bacteria.

Micro Filtration

This type of filtration passes h2o through a porous filtering material. It will remove sediments and suspended materials but it does not remove fine particles or dissolved substances.

Ultra Micro Filtration

Works the same way as micro filtration which removes sediments and extremely fine particles and microorganisms.

Reverse Osmosis

Reverse osmosis is a very popular type of water filtration because it is very successful in removing nearly all contaminants of some sort and is very easy to maintain. It does require a lot of liquid for reverse osmosis to be successful. Put very simply, most reverse osmosis filter units will have a pre-filter that the water goes through first which strains out sediment. From there it goes through a cellophane like membrane that filters out even smaller pollutants. Before it comes out of the special faucet mounted on your sink, the water goes through one last carbon filter that removes any chemicals picked up along the way. It will successfully remove lead, sulfate, sodium, chloride, calcium, magnesium, potassium, manganese, aluminum, nitrate, fluoride, most microorganisms and organic chemicals. It works great as a whole house filtration system when combined with other filtration technologies.

Ultraviolet Radiation

This type of  filtration will remove bacteria and viruses and sanitize your water. It does not however remove suspended particles or ions and is therefore very useful when combined with another technology. It works by using a low level ultraviolet light that kills the bacterial and viral pathogens.

Hopefully these explanations will help to clear up any confusion about how water filters work. The main point to take away from here is that each filtration technology works well on their own to clean certain pollutants. However they are best used in combination with one or more technologies to really ensure that we are safe for drinking, cooking and/or bathing.

Water Electrolysis

Two simple demonstrations of water electrolysis. The first demonstration was learned at the 2010 CSTA Conference at Tara Krisch’s (Orange Grove Middle School) presentation on compounds.