Industrial RO & UF
Reverse osmosis has numerous applications nowadays in a number of fields. These are just some examples:
In industry, reverse osmosis removes minerals from boiler water at power plants. The water is boiled and condensed repeatedly. It must be as pure as possible so that it does not leave deposits on the machinery or cause corrosion. It is also used to clean effluent and brackish groundwater.
The process of reverse osmosis can be used for the production of deionized water.
In addition to desalination, reverse osmosis is a more economical operation for concentrating food liquids (such as fruit juices) than conventional heat-treatment processes. Research has been done on concentration of orange juice and tomato juice. Its advantages include a low operating cost and the ability to avoid heat treatment processes, which makes it suitable for heat-sensitive substances like the protein and enzymes found in most food products.
Reverse osmosis is extensively used in the dairy industry for the production of whey protein powders and for the concentration of milk to reduce shipping costs. In whey applications, the whey (liquid remaining after cheese manufacture) is pre-concentrated with RO from 6% total solids to 10-20% total solids before UF (ultrafiltration) processing.
Although use of the process was once frowned upon in the wine industry, it is now widely understood and used.
Because of its lower mineral content, Reverse Osmosis water is often used in car washes during the final vehicle rinse to prevent water spotting on the vehicle. Reverse osmosis water displaces the mineral-heavy reclamation water (municipal water). Reverse Osmosis water also enables the car wash operators to reduce the demands on the vehicle drying equipment such as air blowers.
Some maple syrop producers use reverse osmosis to remove water from sap before being further boiled down to syrop. The use of reverse osmosis allows approximately 75–80% of the water to be removed from the sap, reducing energy consumption and exposure of the syrup to high temperatures.
For small scale production of hydrogen, reverse osmosis is sometimes used to prevent formation of minerals on the surface of electrodes and to remove organics from drinking water.
Many reef aquarium keepers use reverse osmosis systems for their artificial mixture of seawater. Ordinary tap water can often contain excessive chlorine, chloramines, copper, nitrogen, phosphates, silicates, or many other chemicals detrimental to the sensitive organisms in a reef environment. Contaminants such as nitrogen compounds and phosphates can lead to excessive, and unwanted, algae growth. An effective combination of both reverse osmosis and deionization is the most popular among reef aquarium keepers and is preferred above other water purification processes due to the low cost of ownership and minimal running costs.
Areas that have no or limited surface water or groundwater may choose to desalinate seawater or brackish water to obtain drinking water . Reverse osmosis is the most common method of desalination. Large reverse osmosis and multistage flash desalination plants are used in the Middle East.