Reverse osmosis (RO) is a water purification process in which water is forced through a semi-permeable membrane that removes 90-99% of tap water impurities. The result is water that is free of minerals and other contaminants. Reverse Osmosis, a water treatment method traditionally known for removing salt from seawater, is also used to purify drinking water by forcing untreated water molecules through a semi-permeable membrane or filter. The membrane blocks contaminants and the impurities are subsequently expelled from the environment. The result is pure, clean drinking water.
Reverse osmosis ( RO), also known as hyper filtration, is the finest filtration available today. It is the most common treatment technology used by premium bottled water companies. It is effective in eliminating or substantially reducing a very wide array of contaminants, and of all technologies used to treat drinking water in residential applications, it has the greatest range of contaminant removal. Reverse osmosis will allow the removal of particles as small as individual ions. The pores in a reverse osmosis membrane are only approximately 0.0005 micron in size (bacteria are 0.2 to 1 micron & viruses are 0.02 to 0.4 microns).
There are two types of reverse osmosis membranes commonly used in home water purification products: Thin Film Composite (TFC) and Cellulose Triacetate (CTA). TFC membranes have considerably higher rejection rates (they will filter out more contaminants) than a CTA membrane, however, they are more susceptible to degradation by chlorine. This is one of the reasons why it is important that a reverse osmosis system include quality activated carbon pre-filters.
A typical RO system is composed of an array of granular activated carbon (GAC) pre-filters, the reverse osmosis membrane, a storage tank, and a faucet to deliver the purified water to your countertop. Reverse osmosis systems vary in membrane quality, output capacity, and storage capacity.
Tap water often contains impurities that can cause health. These include phosphate, nitrate, chlorine, and various heavy metals.
Unfortunately, Chlorine, and other common chemical disinfectants, may have a damaging impact on our bodies’ beneficial bacteria as well.
When chlorine is used as a water treatment, it combines with organic matter to form compounds called trihalomethanes (THMs), also known as disinfectant byproducts. One of the most common THMs formed is chloroform, which is a known carcinogen. (2) Other THMs formed include the di- and trichloramines formed when chloramine is used as a disinfecting agent. (3) These compounds are toxic when consumed, inhaled, or applied to the skin.
What Contaminants Does Reverse Osmosis Remove?
Reverse osmosis (RO) units remove substantial amounts of most inorganic chemicals (such as salts, metals, minerals) most microorganisms including cryptosporidium and giardia, and most (but not all) inorganic contaminants.
Reverse osmosis successfully treats water with dissolved minerals and metals such as aluminum, arsenic, barium, cadmium, chloride, chromium, copper, fluoride, magnesium, iron, lead, manganese, mercury, nitrate, selenium, silver, sulfate, and zinc. RO is also effective with asbestos, many taste, color and odor-producing chemicals, particulates, total dissolved solids, turbidity, and radium. When using appropriate activated carbon pre-filtering (commonly included with most RO systems), additional treatment can also be provided for such “volatile” contaminants (VOCs) as benzene, MTBE, trichloroethylene, trihalomethanes, and radon. Essentially, reverse osmosis is capable of rejecting bacteria, salts, sugars, proteins, particles, dyes, heavy metals, chlorine and related by-products, and other contaminants that have a molecular weight of greater than 150-250 daltons. The separation of ions with reverse osmosis is aided by charged particles. This means that dissolved ions that carry a charge, such as salts, are more likely to be rejected by the membrane than those that are not charged, such as organics. The larger the charge and the larger the particle, the more likely it will be rejected.
Reverse Osmosis Units are Usually incorporated with other Energy Solutions to provide sustainable Energy
Benefits of Reverse Osmosis:
- Pure, clean drinking water.
- Removal of unwanted odors or tastes
- More robust tasting beverages that are mixed with Reverse Osmosis treated water (coffee, tea, etc.)
- Requires minimal maintenance
- Convenient- pure, clean water at the touch of a finger
- While not practical for purifying public water supply, an in-home Reverse Osmosis system can be cost effective when compared to other home water filtration methods.
How does it work?