Desalination helps supply freshwater in areas that struggle to get enough safe and clean natural water. Since the need for freshwater is on the rise, many approaches have been invented for turning seawater into clean water for human use. It explains the main types of sea desalination and their benefits, plus the situations they are used for.
Reverse Osmosis (RO)
Desalination systems that use Reverse Osmosis are widely used in countries all over the world. It makes use of a semitransparent membrane to help separate the impurities in seawater from the clean water. When pressure is applied to one side of the membrane, it makes pure water cross through it while salts and other impurities stay put on the other side.
People choose RO because it is very efficient and can filter out up to 99 percent of salts and impurities. It is applied in a wide variety of projects, no matter their size. Nonetheless, the method is not very energy-efficient, and the membranes must often be serviced or changed because they develop fouling or scaling. Nevertheless, improvements in membranes and energy capturing devices are bringing down expenses and making water treatment more efficient.
Multi-stage Flash (MSF)
It means the process sequentially heats and evaporates seawater at several levels of pressure. In this case, seawater is heated and turned into steam in several different sections. Less pressure in each step leads the remaining liquid to turn into steam and then get turned back into fresh water.
Place areas that have lots of waste heat, such as those around power plants, are where MSF is very effective. It is famous for providing reliable water and satisfying the needs of many people. Since MSF plants are complicated and use energy mainly from fossil fuels or process heat from factories, they tend to be less sustainable than other plant designs.
Multi-effect Distillation (MED)
Multi-effect Distillation (MED) is another desalination method, and, unlike MSF, it is most often more efficient in using energy. MED separates the job of evaporating water into several “effects” or stages, at lower and lower pressure and temperature.
Seawater is boiled for each effect, and the created steam is sent to warm the next one. Compared to MSF, this process helps use less energy and reduces what it costs to operate. MED is usually combined with other techniques to help a company work more efficiently. It is used the most in places with lots of industrial activities since it can work with already available heaters. Also, similar to MSF, MED needs to invest in expensive equipment and set up adequate infrastructure.
Electrodialysis (ED)
ED stands for electrodialysis and is a method where electrical force is used to separate salts out of water through selective membranes. ED uses a different method from other technologies, letting desalination take place at regular temperature and cutting down on energy needed.
Using ED is most helpful in desalinating low salt-loaded brackish water. It is applied in farming, industry, and small places, bringing the bonus of superb ion removal. Still, when the water is very salty, like in seawater, it becomes less effective and, therefore, is seldom applied in seawater without adjustments.
Solar Desalination Technology
By using Solar Desalination Technology, solar energy is used to clean ocean water, giving an environmentally safe and sustainable way to provide water. You can divide solar energy into solar stills and concentrated solar power (CSP) systems.
Like how the Sun works on Earth, solar images use solar energy to convert seawater into freshwater. Since they are simple and inexpensive, their main disadvantage is that they do not produce much. Mirrors or lenses are used to focus on sunbeam on a receiver with CSP system, thus heating the water for pilgrimage using MSF or Med.
Solar Desalination is found to have an excellent option in places where there are lots of sunny days and power supply is not easy. Technology produces the results of greenery, as well as it can combine with projects for renewable energy. Nevertheless, presenting these systems can be difficult due to expenses and the required location.
In all, each of the desalination has its own professionals and opposition of the process, and selected technology usually reflects the site's energy resources, water nature, and the rates of use. Since the world requires more durable water and is to advance, make and improve technology, it is important to improve water challenges worldwide.
