To understand reverse osmosis we need to define what osmosis is as a natural principle.

Osmosis is a natural process where molecules move through a semipermeable membrane from an area of higher water concentration to an area of lower water concentration. Imagine two solutions separated by a membrane - pure water on one side and salty water on the other. The molecules will naturally flow toward the salty side to try to equalise the concentration, causing that side to increase in volume.

Reverse osmosis (RO) is essentially forcing this natural process backward by applying pressure. In RO systems, pressure is used to push water through a semipermeable membrane, leaving contaminants behind. The membrane has tiny pores that allow water molecules through but block larger molecules like dissolved salts, bacteria, and other impurities.

Some common applications:

• Purification and desalination plants use reverse osmosis to produce drinking water from seawater or brackish water.

• Concentration of desirable materials using plant in combination with other technologies such as wastewater, beverage and dairy processing.

• Wastewater recovery to reduce water discharge and reuse the permeate water for other uses at the facility.