Companies keen to scrape the ocean floor 5,000 to 6,000 metres below sea level stand to earn billions harvesting manganese, cobalt, copper and nickel currently used to build batteries for electric vehicles.

But the extraction process would disfigure what may be the most pristine ecosystem on the planet and could take millennia, if not longer, for nature to repair.

The deep-sea jewels in question, called polymetallic nodules, grow with the help of microbes over millions of years around a kernel of organic matter, such as a shark’s tooth or the ear-bone of a whale.

“They are living rocks, not just dead stones,” former US National Oceanic and Atmospheric Administration (NOAA) chief scientist Sylvia Earle said in Lisbon.

read on

I’d need to see their detailed analysis comparing the environmental damage with the land-based mining of equivalent resources.

roughbarked said:

Companies keen to scrape the ocean floor 5,000 to 6,000 metres below sea level stand to earn billions harvesting manganese, cobalt, copper and nickel currently used to build batteries for electric vehicles.

But the extraction process would disfigure what may be the most pristine ecosystem on the planet and could take millennia, if not longer, for nature to repair.

The deep-sea jewels in question, called polymetallic nodules, grow with the help of microbes over millions of years around a kernel of organic matter, such as a shark’s tooth or the ear-bone of a whale.

“They are living rocks, not just dead stones,” former US National Oceanic and Atmospheric Administration (NOAA) chief scientist Sylvia Earle said in Lisbon.

read on

I used to be very much in favour of deep sea mining of manganese nodules, but now I’m not so sure.

Yes I have thought of the colonies of microbes growing on these nodules. But all of these microbes are as common as muck, we’re not talking extinction here. Or even significant depletion of numbers.

The main argument against the mining of manganese nodules has been that manganese prices would crash, making the project uneconomical. My response to that was that a much lower price for manganese would allow the use of new manganese alloys in engineering applications. Particularly as a replacement for steel.

Manganese is harder than steel, so manganese alloys containing iron could easily replace iron alloys containing manganese.

For a while I could see only one disadvantage to using manganese as a replacement for steel in civil and mechanical engineering construction. That disadvantage is that manganese has a higher thermal expansion coefficient. But we already design to adapt to thermal expansion, so a change in expansion coefficient isn’t going to be that significant, we can design around it.

It’s only a couple of days ago that I discovered that manganese is flammable, which is a distinct disadvantage compared to most engineering metals. You don’t want the structure of a skyscraper to contribute to fuelling the flames inside, we already have enough trouble with that from furnishings and partitions.

It would be possible to design non-flammable alloys for manganese. It’s already been done with lithium and magnesium alloys, and those are both far more flammable than manganese. Even iron is flammable in some circumstances.

So a lot of research effort into manganese alloys would be needed before starting to mine seabed manganese nodules. I would be happy to participate in this research.

>>Yes I have thought of the colonies of microbes growing on these nodules. But all of these microbes are as common as muck, we’re not talking extinction here. Or even significant depletion of numbers.<<

They say much the same about trees, but there are far more than just trees, there is the ecosystem where MANY organisms live. It is typical, if we see something we want, we take it without much thought about the damage done to the environment.

PermeateFree said:

>>Yes I have thought of the colonies of microbes growing on these nodules. But all of these microbes are as common as muck, we’re not talking extinction here. Or even significant depletion of numbers.<<

They say much the same about trees, but there are far more than just trees, there is the ecosystem where MANY organisms live. It is typical, if we see something we want, we take it without much thought about the damage done to the environment.

Which is fine for organisms that are not in plague proportions. Unfortunately, humans are…

dv said:

I’d need to see their detailed analysis comparing the environmental damage with the land-based mining of equivalent resources.

We aren’t getting that yet as far as I can currently discern.

Michael V said:

PermeateFree said:

>>Yes I have thought of the colonies of microbes growing on these nodules. But all of these microbes are as common as muck, we’re not talking extinction here. Or even significant depletion of numbers.<<

They say much the same about trees, but there are far more than just trees, there is the ecosystem where MANY organisms live. It is typical, if we see something we want, we take it without much thought about the damage done to the environment.

Which is fine for organisms that are not in plague proportions. Unfortunately, humans are…

Always something to think about.

PermeateFree said:

>>Yes I have thought of the colonies of microbes growing on these nodules. But all of these microbes are as common as muck, we’re not talking extinction here. Or even significant depletion of numbers.<<

They say much the same about trees, but there are far more than just trees, there is the ecosystem where MANY organisms live. It is typical, if we see something we want, we take it without much thought about the damage done to the environment.

You don’t see a difference between a tree and a microbe?

mollwollfumble said:

PermeateFree said:

>>Yes I have thought of the colonies of microbes growing on these nodules. But all of these microbes are as common as muck, we’re not talking extinction here. Or even significant depletion of numbers.<<

They say much the same about trees, but there are far more than just trees, there is the ecosystem where MANY organisms live. It is typical, if we see something we want, we take it without much thought about the damage done to the environment.

You don’t see a difference between a tree and a microbe?

You read no more and no less than what is of specific interest to yourself. Why not read it all and have a millisecond think on it.

PermeateFree said:

mollwollfumble said:

PermeateFree said:

>>Yes I have thought of the colonies of microbes growing on these nodules. But all of these microbes are as common as muck, we’re not talking extinction here. Or even significant depletion of numbers.<<

They say much the same about trees, but there are far more than just trees, there is the ecosystem where MANY organisms live. It is typical, if we see something we want, we take it without much thought about the damage done to the environment.

You don’t see a difference between a tree and a microbe?

You read no more and no less than what is of specific interest to yourself. Why not read it all and have a millisecond think on it.

Every tree is a metropolis.

roughbarked said:

PermeateFree said:

mollwollfumble said:

You don’t see a difference between a tree and a microbe?

You read no more and no less than what is of specific interest to yourself. Why not read it all and have a millisecond think on it.

Every tree is a metropolis.

THANK GOD!

…………………..runs away…………………………

roughbarked said:

PermeateFree said:

mollwollfumble said:

You don’t see a difference between a tree and a microbe?

You read no more and no less than what is of specific interest to yourself. Why not read it all and have a millisecond think on it.

Every tree is a metropolis.

Exactly. Yes. That’s why oldest growth forests (such as those destroyed by herbicide in the Vietnam War) needed protection.

One argument about deep sea mining of manganese nodules it the cost to bring such nodules up to the surface.

But that problem can be overcome by a pulley. Take the ship out to the mine site loaded with rock, then use the weight of the rock on one side of a pulley to bring up dredged nodules on the other side. The weights balance closely enough that the mechanical energy required for mining becomes negligible by comparison.

Using the pulley method has another advantage. The rocks sent down provide a new habitat for all the undersea micro-organisms. Minimal environmental sub-sea disruption.