What is a Reverse Osmosis Water Filter?

A reverse osmosis water filter is a type of water filter that is used when there is concern about a wide range of contaminant in drinking water. It uses a mechanical process and so does not require electricity or any other power source.

The system removes about everything including strips of lead, arsenic, cadmium, copper, giardia, chlorine, salt, pesticides, sulfates, nitrates, and cysts of worms, if any. The device propels water into a prefilter where sediments are trapped. The water then passes through a cellophane-like membrane that removes other smaller contaminants. The clean water gets a final screening from a carbon filter before it reaches the special faucet on the sink.

By using a reverse osmosis water filter, you are assured that there are three barriers that screen out contaminants from your water, without the use of electricity. The only problem is the filter wastes gallons of water from filtering. However, those gallons of water do keep the semi-permeable membrane clean. The more water rejected, the cleaner the membrane becomes.

Installing a reverse osmosis water filter should not be hard unless you do it yourself. It's best to call a professional-dial a plumber!

The regular price of the filter is usually under $200. However, the membrane needs replacement every three to five years. Also, the filtered water will cost you seven cents per gallon.

The name of the filter is taken from the same process, reverse osmosis. Reverse osmosis is also called hyperfiltration. The membrane used in reverse osmosis is semi-permeable. The membrane allows the concentrated water that has been cleaned to pass through as it removes dirt and other contaminants. The process known as crossflow is used in a reverse osmosis filter in order to compel the membrane to clean itself continuously. The particles that have been removed from the water are directed towards thick brine reject water.

In order to further understand the idea behind reverse osmosis filter, the concept of osmosis must be clearly understood. Osmosis requires that water passes from an area of greater concentration to an area of lesser concentration. Inside the filter, as the unclean water passes, the area with greater concentration is where the sediments are. As sediments and other contaminants are trapped, pure water is then propelled in the downstream direction.

Reverse osmosis can remove salts, sugars, particles, bacteria, dyes, proteins, and other particles possessing a molecular weight of greater than 150-250 daltons. Charged particles such as salt help in the process of reverse osmosis. Those ions that possess a charge are easily rejected by the semi-permeable membrane. If the charge of an ion is greater, then its rejection in the filter is already predictable.

If you are the type to worry endlessly about the state of your drinking water and if water filters still make you doubt the cleanliness of your water, then a reverse osmosis filter may be what you need. The three levels of filtration process within the device should be enough to put your worries to rest.