The Red Sea - Dead Sea project

 For decades a proposal was being considered by Israel to bring Mediterranean sea water through canals and pipes to the Dead Sea but the project has been scrapped due to political problems and the worry that the sea water might contaminate the ground water of the West Bank.  Now there is a proposal by Jordan to bring Red Sea water to the Dead Sea, mainly by canal.  This project would be all in the territory of Jordan, traveling through a desert area along the Eastern side of Wadi Araba.  What benefits could accrue from such a project.  First a little background.

 

 

The Dead sea is about 430m (1412ft)below sea level.  It is in a desert area and is fed from the Jordan river which flows down the rift valley from the Sea of Galilee (Kenerit) to the North and from many small streams that come down from the ridge of mountains which Jerusalem is located on to the west.  When the Jordan river flowed unhindered, the amount of water entering the Dead Sea more or less matched the water evaporating from it's surface but since much of this water is now extracted for agriculture, the Dead Sea is falling year by year.  Chemical plants at the south end of the Dead sea operate evaporation-ponds to extract the solids from the water and refine them into a number of valuable products*.  This is also contributing to the lowering of the Dead Sea.  The salinity of the Dead Sea is about 10 times the salinity of the open ocean.  This will become quite important as we go through the benefits of the Red-Dead project.  So what benefits could result from the project.

* MgCl, NaCl, KCl, CaCl2, NaOH

 

                 Benefits from a Red Sea - Dead Sea Canal

 

Production of fresh water

The go-to method of producing fresh water from sea water is reverse osmosis.  It is energetically more efficient than Multi-stage flash distillation methods that require heat and vacuum pumps but still takes a lot of energy.  Ocean water is pressurized to about 30 atmospheres and pressed against membranes that allow water molecules to pass but not salt molecules.  Essentially, on a micro scale, you are sieving the salt out of the ocean water.  Incidentally, you can also use brackish ground water and sieve the solutes out of it.  Whatever the source of water, you are left with fresh water and a concentrated salt solution (brine).  The  brine is sent back to the ocean or can be evaporated in ponds to obtain the salts dissolved in the brine.

Since the Dead Sea is 430m below sea level, water piped from the North end of the canal to the Dead Sea will have a pressure of 43 Atmospheres if you drop the ocean water in a pipe to the Dead Sea, that is  more than enough for reverse osmosis.  In fact, you could produce the fresh water higher up on the slope of the Dead sea and have 'head' to pipe the fresh water to a wide area. Clearly there will be energy costs in bringing the water from the Red Sea to the Dead Sea but once the water is at the North end of the canal, there are no added energy costs to operate a reverse osmosis plant.  The brine which is the waste product, can be allowed to flow into the Dead Sea with none of the ecological problems of returning this waste product to the ocean.  As a matter of fact, it will have the benefit of slowing down or reversing the falling level of the Dead Sea.

Production of Electricity

Dropping this water through turbines will create massive amounts of electricity.  Some of the energy could be used to bring the water from the Red Sea and the rest will be available to the people of Jordan at very reasonable costs.  Actually, the whole area is so sunny that the cost of running a power line from the generators back south along the Arava Valley to the Red Sea could probably be avoided by installing solar panels on every house in Aqaba and some more on the desert to the East.  Also, at the Aqaba end there is a very dependable North prevailing wind  which could power a wind turbine.  In the rare times when the wind is not blowing from the North, it is coming from the South. The combination of solar panels and wind turbines might  be less expensive than a high voltage power line all the way from the Dead Sea to Aqaba.  A pond at the North end of the canal would serve as an 'energy storage' device to average out any variability in the power source.

Vegetable production

From 300m down the slope, to the shore of the Dead Sea, vegetables can be grown using the fresh water produced, with no pumping costs for the fresh water produced.  It will flow by gravity.  I say half way down because that is the highest point that fresh water can be produced using the 'head' of the water from the North end of the canal. (30 atmospheres of pressure = 300m).  Of course the fresh water could be pumped uphill to access more land or even pumped to the rest of Jordan for domestic use.

Sea food production

The research station in Elat run by the Oceanographic and Limnological Research Company has done years of research growing fish, crustaceans and oysters in the waters of the Red Sea - mostly in ponds but also in other growing systems.  Marine algae would be an easy addition to this package.  The whole package has been worked out and is available and the relations between Jordan and Israel are pretty good for a couple of Middle East countries*.  The Palestinian people are known for their enterprise and capability.  They would take to growing such products for the European market like, well, fish to water.

*Hard to believe but there is more stress between Arab countries than between Israel and Arab countries.

Production of more fresh water and/or more electricity.

I have never understood how this  works but if you have water of two different saltines you can use them in a device that produces electricity.  Or, using a three cell system, you can produce fresh water instead.  The waters from the Red and Dead seas with their different salinities should be ideal for such a system.

Producing yet more electricity

There is a system using 'solar ponds' to produce electricity.  This one is much easier to understand.

You set up ponds with a salinity gradient from low salinity at the top to high salinity at the bottom. With the Red-Dead project we have three sources of water of different salinity.  Ponds are a few meters deep.  You have to keep any algae from growing in the upper water and regular swimming pool technology is used here.  Think how clear the water is in a hotel swimming pool.  Sun light, which shines for approximately 364 days of the year in this region, goes straight through the upper layers without being absorbed and heats up the bottom of the pond which heats up the lower layers of water.  Because of the salinity gradient, convection does not occur and the heat stays in the lower levels.  The bottom layers get really really hot.

We actually experienced this in a natural pond just south of Elat.  On the west shore of the Red Sea just south of Elat, there is a pond and when the tide is high, sea water can flow through the gravel into the pond.  When the tide goes out, the algae mats seal the pond.  This has resulted in a salinity gradient.  You can swim in the upper layers and it is sometimes quite cool, but hang vertically in the water and lower your feet down and it is too hot to tolerate.

Anyway, you install metal pipes in the lower part of the pond and bring them up to the surface through a lagged (insulated) pipe to an electrical generator.  You use a refrigeration fluid in the pipes.  The fluid is boiled in the pipes at the bottom of the pond and powers the generator above the pond and the condensed working fluid flows back down to the pipes in the bottom of the pond.  Such a system was run many decades ago at one of the hotels on the western side of the Dead Sea. If memory serves me right, it was a 7ha pond.

 

And still more electricity

There is a possibility that over time as you allow more and more water of less salinity than the Dead Sea into the Dead Sea that the whole Dead sea might become a solar lake with the deeper water heating up and the heat held there by the salinity gradient.

Reducing the cost of the chemical extraction factories.

It is getting more and more expensive to pump the Dead Sea brine into evaporation ponds as the surface of the Dead Sea goes down.  This source of water should halt and even reverse this tendency.  If the surface of the Dead Sea gets high enough, water would flow by gravity into the evaporation ponds.  Of course you would still have your pipes going down into the Dead Sea water since there is where the valuable chemicals are.

 

Reversing the damage to the shore

 Pot holes are appearing all over the shore of the Dead Sea, often under the road along the West side of the sea.  This is caused because as the level of the sea falls, small fresh water streams underground are dissolving away the high concentrations of salt in the soil.  With the level of the sea back up, this would cease.

The Red-Dead project would not only be an economic boon to Jordan but would probably engender another layer of cooperation between Israel and Jordan which has to be a good thing.