Reverse osmosis

Reverse osmosis is widely used in industry and drinking water production to remove dissolved salts from water. Typical industrial use cases include the treatment of water required for steam and heat production, as well as surface treatment, manufacturing processes, air humidification, washing and rinsing. In addition, reverse osmosis water is used in brewing, healthcare and many other applications where it is necessary to have water free of minerals before the correct amounts of substances are added. In reverse osmosis, water is separated into permeate (filtered water) and concentrate (stream of residual water that includes all filtered substances). The proportion of permeate and concentrate varies. The yield is usually between 70-80% with fresh water and 30-60% with salt and sea water.

System configuration

As a rule, reverse osmosis feed water requires pretreatment. This is the only way to ensure that the efficiency of the system remains at a good level and to prevent scale formation on the membrane. Typical pretreatment stages consist of multimedia filtration (when there are insoluble solids in the water) and softening (usually applied if the hardness is greater than 5° dH). Instead of a water softener, it is possible to use antiscalant dosing before RO (a chemical that prevents the formation of scale). With a single-stage reverse osmosis system, it is possible to reduce dissolved solids (TDS) by 99.5%.

Necessary data for system design

Raw water analysis along with required water flow/system capacity and required post-treatment water quality or produced water usage information is required to complete the reverse osmosis system design. If the equipment is being installed in an existing space, it is also good to know information about the available drainage and the dimensions of the room.