Mining minerals from seawater

The world needs clean water, and more and more, we're pulling it from the oceans, desalinating it, and drinking it. But what to do with the salty brine left behind? In this intriguing short talk, TED Fellow Damian Palin proposes an idea: Mine it for other minerals we need, with the help of some collaborative metal-munching bacteria.

I collaborate with bacteria.

And I'm about to show you

some stop-motion footage that I made recently

where you'll see bacteria accumulating minerals

from their environment

over the period of an hour.

So what you're seeing here

is the bacteria metabolizing,

and as they do so

they create an electrical charge.

And this attracts metals

from their local environment.

And these metals accumulate as minerals

on the surface of the bacteria.

One of the most pervasive problems

in the world today for people

is inadequate access

to clean drinking water.

And the desalination process

is one where we take out salts.

We can use it for drinking and agriculture.

Removing the salts from water --

particularly seawater --

through reverse osmosis

is a critical technique

for countries who do not have access to clean drinking water

around the globe.

So seawater reverse osmosis

is a membrane-filtration technology.

We take the water from the sea

and we apply pressure.

And this pressure forces the seawater

through a membrane.

This takes energy,

producing clean water.

But we're also left with a concentrated salt solution, or brine.

But the process is very expensive

and it's cost-prohibitive for many countries around the globe.

And also, the brine that's produced

is oftentimes just pumped back out into the sea.

And this is detrimental to the local ecology

of the sea area that it's pumped back out into.

So I work in Singapore at the moment,

and this is a place that's really a leading place

for desalination technology.

And Singapore proposes by 2060

to produce [900] million liters per day

of desalinated water.

But this will produce an equally massive amount

of desalination brine.

And this is where my collaboration with bacteria comes into play.

So what we're doing at the moment

is we're accumulating metals

like calcium, potassium and magnesium

from out of desalination brine.

And this, in terms of magnesium

and the amount of water that I just mentioned,

equates to a $4.5 billion

mining industry for Singapore --

a place that doesn't have any natural resources.

So I'd like you to image a mining industry

in a way that one hasn't existed before;

imagine a mining industry

that doesn't mean defiling the Earth;

imagine bacteria helping us do this

by accumulating and precipitating

and sedimenting minerals

out of desalination brine.

And what you can see here

is the beginning of an industry in a test tube,

a mining industry that is in harmony with nature.

Thank you.

(Applause)