For the survival of humans, animals industries and agricultural sector, fresh water has always been a vital commodity. With the increase in each of the above factors makes an increase in its supply in the future important. As it is becoming a scarce commodity. There are various seawater technologies that have come up which aided significantly in achieving the objective.
Marine water comprises a whole 97% of the aqua storage on earth. This is followed by the glaciers which make up only 2% of the summation. Surprisingly only 0.5% is the one available for humanity use. This is sourced from inland aqua bodies. Sea aqua being not suitable for domestic and industrial human use has made desalination quite a vital means of providing another source of fresh water.
The desalination process involves separation of the resource into two streams. A fresh stream containing a low concentration of dissolved salts and a concentrated brime stream. The above process requires some form of energy to desalinate and several different technologies are utilized. Over the years a variety of innovations have been developed on the basis of thermal distillation, membrane separation, freezing, electro dialysis, etc. On commercial basis the two most important technologies are based on the MSF and RO technologies although it is viewed that the two processes together with MED (multiple effect distillation) will be dominant and competitive in the future.
One of the technology is the multiple stage flash distillation. It is banked on the flash evaporation principle. This is where evaporation takes place not by causing an increase in the temperature, but instead lowering the pressure. It turns out to be a very economical method since the heating is regenerative. The aqua passes over its heat over to its counterpart as it flashes through each stage.
Another method based on distillation is multiple effect distillation. Considered to thermodynamically efficient. It involves the sea water being undertaken through effects, these are a chain of evaporators. The effects use the law of reduction of pressure. Its economic efficiency is determined by the number of effects. This technology has been recently applied in the Arabian region but in comparison to its counterpart MSF it is still not very utilized although it is rising steadily.
We also have vapor compression distillation. Where through the vapor compression heating the sea water takes place. It applies the principle of reducing pressure in order to lower the boiling temperature. The heat absorbed from the condensation of vapor is utilized in heating the incoming marine aqua. This is achieved by use of steam jet. A compressor can also be used. This method is common in desalination units which run on small scale.
There is also the method of Reverse Osmosis (RO). Where external pressure, more than the osmotic pressure of the marine water, is applied thereby overcoming the osmotic pressure. Therefore leaving behind dissolved salts with the increase in their concentration. In the recent past various developments have emerged to assist in reducing operating cost of the RO plants.
Methods such as solar evaporation, freezing and potabilization are used but not as often as the ones described above.
Marine water comprises a whole 97% of the aqua storage on earth. This is followed by the glaciers which make up only 2% of the summation. Surprisingly only 0.5% is the one available for humanity use. This is sourced from inland aqua bodies. Sea aqua being not suitable for domestic and industrial human use has made desalination quite a vital means of providing another source of fresh water.
The desalination process involves separation of the resource into two streams. A fresh stream containing a low concentration of dissolved salts and a concentrated brime stream. The above process requires some form of energy to desalinate and several different technologies are utilized. Over the years a variety of innovations have been developed on the basis of thermal distillation, membrane separation, freezing, electro dialysis, etc. On commercial basis the two most important technologies are based on the MSF and RO technologies although it is viewed that the two processes together with MED (multiple effect distillation) will be dominant and competitive in the future.
One of the technology is the multiple stage flash distillation. It is banked on the flash evaporation principle. This is where evaporation takes place not by causing an increase in the temperature, but instead lowering the pressure. It turns out to be a very economical method since the heating is regenerative. The aqua passes over its heat over to its counterpart as it flashes through each stage.
Another method based on distillation is multiple effect distillation. Considered to thermodynamically efficient. It involves the sea water being undertaken through effects, these are a chain of evaporators. The effects use the law of reduction of pressure. Its economic efficiency is determined by the number of effects. This technology has been recently applied in the Arabian region but in comparison to its counterpart MSF it is still not very utilized although it is rising steadily.
We also have vapor compression distillation. Where through the vapor compression heating the sea water takes place. It applies the principle of reducing pressure in order to lower the boiling temperature. The heat absorbed from the condensation of vapor is utilized in heating the incoming marine aqua. This is achieved by use of steam jet. A compressor can also be used. This method is common in desalination units which run on small scale.
There is also the method of Reverse Osmosis (RO). Where external pressure, more than the osmotic pressure of the marine water, is applied thereby overcoming the osmotic pressure. Therefore leaving behind dissolved salts with the increase in their concentration. In the recent past various developments have emerged to assist in reducing operating cost of the RO plants.
Methods such as solar evaporation, freezing and potabilization are used but not as often as the ones described above.
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