Glossary of Water Treatment Terms

Glossary Of Terms


Limescale and white deposits left within water systems are a result of the Hardness of the water. Hardness is a measurement of the Calcium and Magnesium dissolved in the water, which can drop out of suspension and cause damaging scale within pipework and boilers. Water softeners can remove this Hardness by a process called Ion Exchange, swapping the harmful Calcium and Magnesium for Sodium which does not form scale.

Ion Exchange

When some elements are dissolved in water they will have either a positive or negative charge. These elements can be exchanged for other elements.

Reverse Osmosis

RO-technique is based on a natural phenomenon: the Reverse Osmosis water treatment process. With the use of mechanical pressure, the natural process is reversed (Reverse Osmosis). By applying force, the pure water starts flowing through a membrane. The solutes are left behind in the thickened water (concentrate) on the other side of the membrane. Depending on the type of the membrane; salts, organic compounds, and particulates, amongst other matter, can be left behind in the concentrate. Through the application of Reverse Osmosis, bacteria (including the Legionella bacteria), as well as viruses, can be prevented. The pure Osmosis water can be used for numerous applications, for example, as irrigation water in the horticultural industry, as supply water for boiler and cooling systems, or as process water in the industrial sector.

Water Softener

The most effective method of industrial water softening solutions (removing the hardness salts Calcium and Magnesium), is by the process of ion exchange – ions are electrically charged species of the minerals dissolved in water. The water is passed through a synthetic resin, which absorbs the Calcium and Magnesium ions by exchanging them for sodium ions. When the resin is exhausted, it needs to be regenerated. The resin is recharged with sodium ions by rinsing with a brine solution (Sodium Chloride). The hardness ions previously removed are flushed to drain during the regeneration process.