Interesting : Beach Sand + Electricity = Rock

[[e-mail]]

https://www.newsnationnow.com/climate/erosion-coastline-seawater-electricity/

A zap of electricity could be the cure for Earth’s ailing
coastlines, new research from Northwestern University found.

The study, published in the journal Communications Earth
and the Environment, observed how electrical currents
affect the structure of marine sand.

The chemical reaction that occurs when electricity is
introduced to sand saturated in seawater, the study says,
almost instantly creates a natural cement.

“As the porous structure of sands progressively fills with
newly formed electrodeposits, the porosity is reduced while
particle contacts increase and are cohesively bonded,” the
study reads. “As a result, the hydraulic conductivity of
marine soils decreases whereas their shearing strength
increases.”

Increased strength could be pivotal in bolstering the world’s
coastlines against erosion, with researchers saying this
natural cement can influence “the structural stability of
coastal and offshore structures.”

“After being treated, the sand looks like a rock. It is still
and solid, instead of granular and incohesive. The minerals
themselves are much stronger than concrete

. . .

Left OUT of the article ... how MUCH electricity.

Full details at :
https://www.nature.com/articles/s43247-024-01604-3

Looks like just four or five volts for a month will
do it, but the AMPS were not clearly cited. It
is the V*A, the WATTS consumed, which decide if
this process is commercially viable or expends
even more energy than making concrete.

[R Kym Horsell]

Post by ***@ud0s4.net
https://www.newsnationnow.com/climate/erosion-coastline-seawater-electricity/
A zap of electricity could be the cure for Earth???s ailing
coastlines, new research from Northwestern University found.

...

Post by ***@ud0s4.net
Left OUT of the article ... how MUCH electricity.

They said 4v. Restivity of wet sand is around 500 ohm.meters so
the power is tiny (milliwatts). If treatment takes 60 sec then
that's 1 J per m3 of sand.

The EU spends 300 million euros a year to keep their beaches
intact under increasing pressure of global warming.
A teensy fraction of that could cement the sand in place each year
using this kind of bright idea.
The EU coastline is 68000 km. An area 1m deep 100m wide
is ~7 billion m3. I.e. 7 GJ or 2000 kwh. I.e. $600 of electricity.
You may not be afford it but the EU could probably pass
a hat around at one of their many annual talkfests and cover it.

Post by ***@ud0s4.net
https://www.nature.com/articles/s43247-024-01604-3
Looks like just four or five volts for a month will
do it, but the AMPS were not clearly cited. It
is the V*A, the WATTS consumed, which decide if
this process is commercially viable or expends
even more energy than making concrete.

[[e-mail]]

Post by R Kym Horsell

Post by ***@ud0s4.net
https://www.newsnationnow.com/climate/erosion-coastline-seawater-electricity/
A zap of electricity could be the cure for Earth???s ailing
coastlines, new research from Northwestern University found.

...

Post by ***@ud0s4.net
Left OUT of the article ... how MUCH electricity.

They said 4v. Restivity of wet sand is around 500 ohm.meters so
the power is tiny (milliwatts). If treatment takes 60 sec then
that's 1 J per m3 of sand.

Wet BEACH sand ... SALT water, lower resistivity,
more watts. Oh, and the treatment, according to
the graphs, is something like up to a month.

Also note this seems to require sea-water as
magnesium salts are involved along with calcium.
Can't just whip up your own water with a little
Morton salt in it. No LACK of sea-water though,
just need to be near the ocean.

Post by R Kym Horsell
The EU spends 300 million euros a year to keep their beaches
intact under increasing pressure of global warming.
A teensy fraction of that could cement the sand in place each year
using this kind of bright idea.

As said, it's interesting. How USEFUL in real-world
situations ... that remains to be seen.

Alas I have seen concrete reinforced shorelines and
what happens is that all the sand goes away, leaving
naught but the hard barrier. No more "beach" or
"dunes" or their micro-ecologies.

I'd like to see something like a pre-fab 12'x8'x8"
wall panel made this way, see how it compares with
concrete AND see a comparison of the energy expended.
Making concrete IS very energy-intensive ... THIS
method, if even maybe a 30% improvement ....

I recently posted some stats on bricks/panels made
by using waste polyethylene to glue sand together.
A 1:4 plastic:sand ratio seems best. It's not AS
strong as concrete, but it's more than strong enough
to build one or two floor HOMES or similar. Again
a kit of pre-fab panels is ideal. There are cottage
industries in Africa now making paving stones and
such with sand and waste plastics already, but they
are kinda crude operations. Better controls and ... ?

I've nothing in particular against alternative building
materials or even EVs ... but they HAVE to be at least
equally economic/functional as what we use now. I'd
especially like to see a lot less WOOD in low/mid-
priced houses - our use of trees is decidedly NOT
'sustainable' and it's 50+ years to grow more.

Post by R Kym Horsell
The EU coastline is 68000 km. An area 1m deep 100m wide
is ~7 billion m3. I.e. 7 GJ or 2000 kwh. I.e. $600 of electricity.
You may not be afford it but the EU could probably pass
a hat around at one of their many annual talkfests and cover it.

Post by ***@ud0s4.net
https://www.nature.com/articles/s43247-024-01604-3
Looks like just four or five volts for a month will
do it, but the AMPS were not clearly cited. It
is the V*A, the WATTS consumed, which decide if
this process is commercially viable or expends
even more energy than making concrete.