Continuation and Conclusion of our adventure in the Technion :
Flashback on the last episode: We met Dr Semiat, researcher and teacher at the Technion, who speaks us long about the Israeli water situation, bringing an interesting point of view concerning the place of water in the situation of Middle-East. If you want to know more, it is here! http://wp.me/p6R91a-91
Then, Docteur Semiat talked about his researches. And he is a specialist in many fields: membranes, desalinization, waste water!
His hobby is desalinization. When we went out from the desalinization plant of Ashkelon, we were impressed with the efficiency of this plant. But we wondered where are the drawbacks?
According to Dr Semiat, they don’t exist.
Concerning the energy, two third of the water production occur during the night using the electricity which would be wasted if it is not used. It represents less than 3% of the national energy consumption. It is less than the energy needed to bring water from North to South!
The problem of the high concentrated sea water, which comes from the plant, is not a problem! It is mixed with a lot of water when it goes out from the industry. So, it is only 12.5% higher than the sea water. And the impact seems to be very little. “ Do we mater about fresh water of the rivers who go to the ocean?” Dr Semiat caricatures
Concerning the price, the desalinated water is cheaper than the water in Paris!!!! The consumer pays only 9 Shekel (approximately 2.25€) the cubic meter whereas in Paris, he pays 3.3€. Wonderful!!!!!
So we looked for the fly in the ointment during our trip after the meeting and we found it. The desalinated water is poor in minerals. The consequence is health problems for people.
One of the main problems in desalination is that membranes become often clogged. Docteur Semiat discovers a very simple innovation to fight against it. The plant must be stopped. Then, the fresh water goes naturally from one side of the membrane to the other (which is clogged of salt) and where there is the salted water ( it the osmosis theory). When it goes through, it washes the membranes. And so their lifetime increase.
Dr Semiat could patent its invention but he didn’t ! Why? He only wanted to help the desalinization industry!
According to him, the wasted water are future major challenge for the environment. We will go to an environmental and health disaster with the water rejected and containing drugs and other molecules. His solution? We must apply other treatment method where membranes have a role to play.