Sunday,22 October, 2017
Current issue | Issue 1271, (19-25 November 2015)
Sunday,22 October, 2017
Issue 1271, (19-25 November 2015)

Ahram Weekly

From salt to sweet

Researchers in Alexandria University have discovered a new method of seawater desalination

Al-Ahram Weekly

Herodotus wrote in 450 BC that “Egypt is the gift of the Nile.” Since time immemorial, Egyptians have known that their prosperity depends on the river’s annual flood, which has been recorded for more than three millennia, reports Ameera Fouad.

However, problems started to emerge in the 21st-century. Egypt is now facing a dispute over the sharing of Nile waters with the building of Africa’s biggest hydroelectric dam in Ethiopia. This is because the Nile is Egypt’s only source of water; in fact, its source of life.

The world is fighting for affordable drinkable water, even though, paradoxically, water covers 70 per cent of the earth’s surface. With the world getting thirstier and global demand for fresh water rising by 640 billion litres a year, scientists are working to convert seawater into fresh water.

The Nile River provides more than 50 billion cubic metres of water every year. This represents 97 per cent of the country’s renewable water resources, which stand at 56.8 billion cubic metres per year. In 2010, the average amount of water used each day by an Egyptian person was 126 litres.

Thus, with all the Nile disputes and the high consumption of fresh water, we are in dire need of new sources of fresh water. Seawater desalination could be such a source. However, due to the high costs involved, desalination plays only a minor role in providing water for Egyptians.

Five years ago, the government considered available methods to desalinate seawater, including reverse osmosis, as too costly. Reverse osmosis involves forcing water through cartridges containing composite polyamide membranes that trap salt and other impurities but allow fresh water through.

A breakthrough discovery by four researchers at Alexandria University would make the process more affordable. The new process uses a membrane that extracts fresh water from the sea through evaporation.

The researchers — Mona Mahmoud Naeem, Abeer Moneer, Mohamed Elewa and Ahmed Al-Shafei — belong to the Faculty of Engineering and Faculty of Science at Alexandria University and Arab Academy for Science, Technology and Maritime Transport (AAST). The innovative new membrane is a polymeric that desalinates seawater in a purge-air pervaporation process.

Such research cannot be conducted on the spur of the moment: it needs years of thorough inspection and scientific examination.

Naeem, an emeritus professor in her seventies, told Al-Ahram Weekly, “Yes, we worked on this research paper in the nineties, when I first went on a Fulbright scholarship in the US, where I was first introduced to this science of pervaporation.”

She continued, “In 2010, we competed in a scientific research competition made by the SDF [Social Fund for Development] for the best research conducted in seawater desalination. And, consequently, we submitted two abstracts.

“Out of 150 abstracts, only seven were chosen to receive the fund. Of the seven, the two research papers we submitted won two places and we were given the financial award.

“Of course the award helped us a lot in finalising our projects and our research materials. Though it took us around four years to come up with these results due to political turmoil the country went through, we were more than happy that all our efforts were rewarded.”

The SDF funding gave each winning team LE1.4 million, a relatively small sum in the advanced technology world of seawater desalination. But the researchers pressed on in their pursuit of a development that would benefit their country, even if they sometimes had to cover costs with their own money.

“These are modern and very advanced techniques that no one had ever discovered in the liquid membrane branch,” Naeem said. Such advances have many advantages, including splitting azeotropes (constant boiling vapours).

It will also work with seawater, even the highly salinised water of the Red Sea. It also purifies water that has been contaminated with sewage and/or dirt, which makes it beneficial for use in developing nations.

“We could also replace the high temperature with solar energy and this technique could be used in high-temperature countries such as Saudi Arabia,” added Naeem.

What’s most enthralling is that the materials cost almost nothing. Desalination using pervaporation is a relatively inexpensive process.

“After getting the fund, we had an obligation to submit our research papers and to start real work. Throughout those four years, we had many delays due to the country’s turmoil,” she said.

“However, currently, as matters in the country have become relatively stable, we have no justification to stay behind anymore and so we are not waiting for anything except for our project to get implemented so that the country can save millions of pounds.”

It is no surprise that the Ministry of Military Production has shown great interest in adopting and developing the research project. The ministry is well known for developing, encouraging and fostering scientific development in Egypt.

“We haven’t actually heard from the Ministry of Scientific Research or from any other public or private scientific research institution to help realise this research. We thank God that the Ministry of Military Production is taking an interest in the project and will most likely adopt and develop it quickly and accurately,” fellow researcher Moneer added.

“Yes, we owe a big thank you to the SDF, which was the birthplace of this research achievement and with which we travelled to Japan and Italy during this period to present other papers and other scientific researches belonging to this field and elsewhere,” Elewa said.

“What we are aiming at is to turn this research into a prototype which will in turn pave the way to present it in markets.”

The method of pervaporation has been in use since the early 1990s. It is being used in wastewater treatment to separate organic solvents from industrial wastewater.

Desalination of simulated seawater by purge-air pervaporation, using an innovative fabricated membrane, is a scientific breakthrough that could give nations around the world access to affordable drinking water.

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