Researchers at Alexandria University in Egypt have used membranes containing cellulose acetate powder, produced in Egypt, which filters salt particles and makes it easy to desalinate seawater. The membrane is easy to fabricate in any laboratory using cost-effective ingredients and so is an excellent option for developing countries according to the department of agricultural and biosystems engineering at Alexandria University.
The technique used is pervaporation which means the water is first filtered through the membrane to remove larger particles and then vapourised. The vapour is then condensed to get rid of small impurities, and clean water is collected. This process reduces the use of electricity to a large extent and hence is economical.
The membrane technology in combination with vaporisation can be applied in remote settings, as it requires only the membranes for the filtering process, and fire to vaporize the filtered water, the researchers say.
The technology has been around since the mid-90s, Helmy El-Zanfaly, a professor of water contamination at Egypt’s National Research Center to separate organic liquids, like alcohols, and is one of the more common systems used in sewage treatment to separate water from organic solvents.
The existing pervaporation membranes are fabricated using complicated procedures, but the Egyptian method is more economical using the locally available material. The technology implemented in the study is much better than reverse osmosis. The next step for the team is to establish a small desalination unit as a pilot project for the technology.
Source: SciDev.Net
