Seawater desalination is the production of drinking water or process water for industrial or power plants from seawater by reducing the salt content. Desalination can be based on a variety of processes that remove salts and minerals from water.
In some cases, this results in usable by-products such as table salt. Desalination of brackish groundwater is also gaining importance, although the methods are similar to those used for direct seawater desalination.
Seawater desalination will be of great importance in the future, as it is becoming increasingly difficult to supply clean water to all people due to lack or pollution of available fresh water.
On the other hand, seawater desalination has long been practiced on ships, submarines and islands, where cost is not a major factor. (Desalination Process) For the process to work, however, the raw material must have only a very low level of contamination (such as with oil), so that desalination of seawater around major shipping routes is less economical. A land well reaching sea level should then help to pre-filter the sea water.
This form of drinking water supply is widespread in the Middle East. It is the main source of drinking water in the Gulf countries. Most of the drinking water is obtained by gas or oil-fired desalination plants. Combined gas and steam turbine power plants with an attached MSF desalination plant are also used very frequently. On the German island of Helgoland, drinking water is obtained using the reverse osmosis process.
How does the Desalination Process happen
Mainly two systems are used: in the first, sea water is heated by capturing its vapor, and then condensed back into fresh water through a distillation process. The most commonly used technique is what is called “multistage flash distillation”, which is a thermal process for desalting large quantities of seawater.
This process is based on the principle that water boils at a lower temperature when atmospheric pressure is lower. In this case sea water passes through chambers called “stages”, each of which contains a heat exchanger and a condensate collector: when preheated sea water enters the first stage, part of it rapidly boils. It produces steam which condenses into fresh water. on heat exchange tubes.
A second method, highly expensive and energy-intensive (since it uses electricity and not heat like the first system), is so-called reverse osmosis: water in this case, with salts dissolved in it, is essentially high pressure. is pumped on.
Through a semipermeable membrane that blocks the saline components while allowing water molecules to pass through. One of the largest reverse osmosis desalination plants in operation is located in Sorek, Israel, and can produce approximately 627,000 cubic meters of desalinated water per day.
Desalination options in the future
Desalination is a process which is mainly done in developed countries with sufficient funds and resources. If technology continues to produce new methods and better solutions to the issues we are facing today, there will be a new water resource for more and more countries facing drought.
Competition and overpopulation for water. While there are concerns in the scientific world about replacing our current use of water with an outright reliance on seawater, it will undoubtedly be an option for at least many people struggling to survive or maintain their standard of living.
[Desalination Definition and Desalination Process]