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Many methods for water purification and seawater desalinization have been used for a number of years starting in ancient times with good old fashion distillation (boil the water and catch the condensate leaving the bad stuff behind). The leading method now is membrane based...reverse osmosis. Expensive to build, expensive to operate and maintain.
Reverse Osmosis uses pressure to force water molecules through a special membrane with very small pores that trap salts and other dissolved solids (retentate) and results in up to 99% pure water (solute). In low pressure home use, RO usually results in 80% or more waste...5 gallons of waste water are produced for every gallon of useable water. In high pressure systems (1000 psi or more) used in saltwater desalinization, recovery rates can exceed 90%. High pressure systems require alot of energy to run however.
New studies are underway to improve membrane efficiencies (particularly in energy use) include forward osmosis which actually uses an ionic salt process and then removing the special salts from the solute..or good water side..of the membrane process.
Carbon nano-tubes built into membranes and electrically charged to repel salt ions before reaching the membrane, and biomimetic membranes utlizing aquaporins in a similar charged fashion hold some promise to improving the efficiency of RO systems but are still in the theory and development stage.
One new process that is actually in commercial development is Capacitive De-ionization which uses a flow-through capacitor designed to eliminate dissolved solids from water using a small electrical charge.
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What are some problems with distillation as a method for desalination?
there are no problems, just other methods are faster.
Can ice be used for desalination?
Basically, desalination of water can be carried out by the following general methods: 1. Distillation 2. Electrodialysis 3. Demineralisation/Deionisation and 4. Reverse osmosis.
What is the difference between water distillation and desalination?
distillation is a method of desalination, one of the many methods. It is done by condensing salt water and then the water evaporates, creating salt free water...yippee poo-poo i have to go
What temperature does it take to desalinate water?
For the desalination by distillation - the boiling point of water. For other methods the temperature is not so important.
Why is desalination bad?
Desalination has very high energy requirements and since most countries with desalination plants do not have nuclear power, it results in the burning of lots of more coal. Additionally, the methods by which salt is removed from water create a resulting "salt-slurry" which is ejected as waste in to the original saltwater body. This salt-slurry makes the area around the desalination plant poisonous for the local sea-life.However, in almost every case, the positives of desalination outweigh these negatives.
What are desalination of sea water?
Desalination of sea water
Why is desalination?
Desalination is the process of removing salt from seawater.
What are process during desalination of sea water osmosis reverse osmosis use of sodium aluminium or none?
Generally distillation or evaporation/recrystallization are important methods.
What are two possible ways to meet peoples future water needs?
Two possible methods of obtaining fresh water for the future are desalination and melting icebergs.
What is a good sentence with the word desalination?
Sometimes they have to do desalination to a sea.
Is expensive because it requires a lot of electricity .?
Desalination.
How is desalination viewed by members of the society?
People view desalination by tours
