How to purify fresh water from seawater is simple, cheap and without electricity

By applying the transpiration method, Egyptian scientists have created a simple, inexpensive, non-electric way to separate drinking water from seawater in just a few minutes, promising to be applied widely. spread in many areas where water is scarce in the world.

How to filter fresh water from sea water quickly and cheaply

Currently, removing salt from sea water seems to be the only way to supply water to poor, developing countries, particularly in Egypt and the Middle East. To do that, people have to build very large refineries, going through many different filtering stages, requiring expensive and expensive equipment.

On the other hand, these plants release large amounts of salt and pollutants back into the ocean, affecting the environment. Therefore, researchers are always looking for cheaper, cleaner and less energy-efficient ways to extract drinking water from seawater.

And in the latest transformation, the team of scientists Mona Naim, Mahmoud Elewa, Ahmed El-Shafei and Abeer Moneer at Alexandria University, Egypt claimed to have developed a new material that helps filter freshwater from seawater. Easy, simple, can apply in most countries around the world without using electricity.

The technique that they use to separate liquids and solids in seawater is called pervaporation (PV - vaporizing, which is a combination of osmosis and evaporation, used to separate liquid mixture by partial evaporation through non-porous selective semi-permeable membrane . This is a simple process with 2 steps: First seawater will be filtered by a ceramic or polymer membrane. The water will then continue to evaporate by the pressure difference between the two ends (the input source is air pressure, the output source is usually vacuum) and condense to produce fresh water.

This approach is said to be faster, cleaner and more energy efficient than conventional filtration because it does not need to use electricity to generate heat to evaporate water. In fact, PV technology is not new, but before that, the film is used very expensive and complex production.

This time, the scientists have breakthroughed in creating a new membrane that is capable of absorbing salt and incorporating cellulose acetate powder to enhance the efficiency of evaporation through the membrane. Cellulose acetate powder is in the form of small fibers, derived from wood, which the team says are cheap, easily found in many places.

This membrane will quickly desalinate in high salinity seawater and can even filter heavily polluted seawater. Besides, if used on a large scale, it can also filter out contaminants and salt crystals to minimize environmental pollution.

Currently, researchers have not announced plans to commercialize this product, but if possible, it will be a promising method for developing countries, where electricity and water are still resources. Extremely scarce raw.