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.
This process entails separation of sea water to two streams. Fresh one with very small concentration of salts dissolved and one with highly concentrated brime. Various forms of energy are required for the success and thereby emergence of different innovations. Different technologies based on different means of achieving this. But not all have a potential future. The MSF, RO and MED have been prophesied to be the dominant means although currently MSF and RO are the widely used.
Multiple stage flash distillation. One of the methods of desalination. It is built on flash evaporation principle. Where evaporation is induced by reduction of pressure instead of increasing of temperature. Its economic advantage is through the regenerative heating. Where the resource gives up its heat to its counterpart on every flash chamber it goes through.
Multiple effect distillation is the form of distillation process. And is also thermodynamically efficient. The process takes place in a series of evaporators called effects and uses the principle of reducing the ambient pressure in the various effects. The MED plant steam economy is proportional to the number of effects. MED plants can have 3 types of tubes, that is, horizontal, vertical or submerged. Most recent application have been in the Middle East. Although their number is still relatively small compared to MSF plants, their numbers have been increasing.
Another technology used is the vapor compression distillation. Here the heating of marine aqua comes from the compression of vapor. The vcd plant takes advantage of principle of reducing the boiling point temperature by reducing pressure. Two methods are used to condense vapor, a mechanical compressor that helps to produce enough heat to vaporize incoming sea water and a steam jet that works the same. This process is normally used for small scale desalination units.
Reverse osmosis, commonly referred to as RO, is where the osmotic pressure is overcome by applying external pressure higher than the osmotic pressure on the sea water. Thus it flows in the reverse direction to the natural flow across the membrane leaving the dissolved salts behind with an increase in salt concentration. Over the past decade a number of developments have been made to help reduce the operating cost of RO plants. These are the development of membranes that can operate efficiently with longer duration and the use of energy recover devices.
These are not the only technologies in use. But the most commonly used ways of desalination as compared to the one mentioned above. We have others such as freezing, potabilization and solar evaporation.
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.
This process entails separation of sea water to two streams. Fresh one with very small concentration of salts dissolved and one with highly concentrated brime. Various forms of energy are required for the success and thereby emergence of different innovations. Different technologies based on different means of achieving this. But not all have a potential future. The MSF, RO and MED have been prophesied to be the dominant means although currently MSF and RO are the widely used.
Multiple stage flash distillation. One of the methods of desalination. It is built on flash evaporation principle. Where evaporation is induced by reduction of pressure instead of increasing of temperature. Its economic advantage is through the regenerative heating. Where the resource gives up its heat to its counterpart on every flash chamber it goes through.
Multiple effect distillation is the form of distillation process. And is also thermodynamically efficient. The process takes place in a series of evaporators called effects and uses the principle of reducing the ambient pressure in the various effects. The MED plant steam economy is proportional to the number of effects. MED plants can have 3 types of tubes, that is, horizontal, vertical or submerged. Most recent application have been in the Middle East. Although their number is still relatively small compared to MSF plants, their numbers have been increasing.
Another technology used is the vapor compression distillation. Here the heating of marine aqua comes from the compression of vapor. The vcd plant takes advantage of principle of reducing the boiling point temperature by reducing pressure. Two methods are used to condense vapor, a mechanical compressor that helps to produce enough heat to vaporize incoming sea water and a steam jet that works the same. This process is normally used for small scale desalination units.
Reverse osmosis, commonly referred to as RO, is where the osmotic pressure is overcome by applying external pressure higher than the osmotic pressure on the sea water. Thus it flows in the reverse direction to the natural flow across the membrane leaving the dissolved salts behind with an increase in salt concentration. Over the past decade a number of developments have been made to help reduce the operating cost of RO plants. These are the development of membranes that can operate efficiently with longer duration and the use of energy recover devices.
These are not the only technologies in use. But the most commonly used ways of desalination as compared to the one mentioned above. We have others such as freezing, potabilization and solar evaporation.
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