Marine water purifiers, also known as desalination systems, use various methods to remove salt and other impurities from seawater or brackish water, making it safe to drink or use for other purposes. One of the most common methods used is reverse osmosis (RO).
In an RO system, seawater is forced through a semi-permeable membrane that allows water molecules to pass through while blocking larger molecules and impurities such as salt and minerals. The resulting purified water is collected, while the remaining salt and other impurities are discharged back into the ocean.
The process of reverse osmosis requires a significant amount of energy, which is typically provided by an onboard generator or through a connection to the ship's electrical system. Some marine water purifiers also incorporate pre-filtration steps to remove larger particles and debris from the seawater before it is processed through the RO membrane.
Other methods used for purifying seawater include distillation, where the seawater is heated to produce steam, which is then collected and condensed into purified water, and electrodialysis, where an electrical charge is used to separate salt and other impurities from the water. However, these methods are less commonly used on ships due to their higher energy requirements and maintenance costs.