Translator: Ilze Garda Reviewer: Peter van de Ven
Like many of you, I enjoy spending Christmas with my family,
and I always do it.
But for the previous three years, this was impossible
because I was on the other side of the Atlantic Ocean
doing my doctorate research.
So instead, we would have Christmas Skype calls,
and even from the U.S.,
I was always a part of the traditional family photo.
And of course, we would have a chat on what's new and how everyone is doing,
but during my final Christmas in the U.S., three years after I had moved there,
I realized that none of my family really knows what is the thing that I do:
Why did I go to the U.S.?
I organized a quick quiz,
and the closest answer that I got came from my sister,
and she said, 'You observe asphalt.'
(Laughter)
I mean, I do all this fancy stuff -
I work in the lab, I go to the conferences -
but all they know is I observe asphalt.
This like watching the grass grow, right?
So let me tell you what did I really do,
and hopefully, they're watching this as well.
Well, I think of asphalt every day,
and I bet that you do it only
if the road that takes you to the work looks something like this:
it's cracked, patched, and full of potholes.
Sadly, this is the situation in too many places,
and all of us pay for it with our own money.
Every euro that is saved on road maintenance
causes two euros worth of damage to cars.
Unfortunately,
road maintenance is far from being a priority in most countries,
so realistically,
we cannot expect the situation to change any time soon.
The backlog for road repair is growing larger every year.
Is there a solution?
Well, I think there is,
but I'll tell you what it is if you answer one simple question:
Which is the most recycled material in the developed world?
Any guesses?
(Audience) Plastic.
OK, I hear 'paper', I hear 'steel', 'metal';
all of these are the traditional perception:
plastic, paper, aluminum.
Well, actually, it is asphalt.
Road pavements
are the most recycled material in the developed world.
In the U.S. alone,
70 million tons of asphalt are recycled annually:
99% of all the available asphalt.
This volume is close the volume of the Great Pyramid of Giza -
every year.
And it's not one Great Pyramid of Giza,
it's actually 11 Great Pyramids of Giza that we produce every year.
Some of this old asphalt is used for production of new asphalt,
but a large portion is downgraded for use in lower-value applications.
Some is used for building the base of new roads,
some is used for road shoulders,
and some of the old highway may even be on the driveway to your home.
I don't want to say that improving your driveway
is a bad way of any resources,
but I think there is an even better way
to recycle the material
that was designed to resist heavy traffic loads on highways.
So during my doctorate research at Worcester Polytechnic Institute,
I advanced a method
that allows to recycle 100% of the old, potholed asphalt
into new and beautiful asphalt.
And when I say 'beautiful asphalt',
I mean the kind of asphalt you can take home and show to your family.
(Laughter)
(Applause)
Well, it kind of makes sense -
any new asphalt consists of stones and the black stuff is bitumen.
Any reclaimed asphalt consists of stones and the black stuff is bitumen.
So why not recycle all of it?
After all, there are not that many materials
that can be truly reused in the same high-value application.
You know, you can take a plastic shopping bag to the store once more,
and perhaps, you can reuse a beer bottle or aluminum,
but for most materials, recycling means downgrading of the value.
A single PET bottle can contain many different materials,
including the bottle itself, the paper label, the glue that holds it,
the remains of the drink, and so on.
So often, plastic bottles are recycled into fibers,
and fibers are later used for production of lower-grade materials,
like carpet and plastic strapping and things like that.
But with asphalt, we can truly reuse the old material into a new one
without lowering its value.
And let me tell you how they think this can be done.
Well, asphalt ages with time.
It becomes stiff, brittle, it starts to crack,
water penetrates into the road structure,
and that's why you see those ugly potholes formed.
This happens because, due to losing the light, oily fractions,
bitumen loses its elasticity, and we need elasticity
to resist deformations caused by the weather and our cars.
So before we can reuse the old asphalt,
we need to bring back this property,
and naturally, the first thing to try
is to see if we can reverse the aging process
by adding the lost oils back.
This is actually not that far
from using oils that are called anti-aging cream on your skin
to reverse your aging process, to rejuvenate your skin.
That's what I was trying to do with bitumen,
I was trying to rejuvenate bitumen.
But since I didn't have any anti-aging cream at hand,
I had to use some other oils,
but choosing which ones to use was actually a very big challenge.
We don't know that much about the chemical structure of bitumen,
or rather, we know that it is so complicated
that there is no way to come up with a single chemical formula for it.
So I couldn't use the chemical approach;
I had to rely on some other techniques,
and in my lab,
I was working with what scientists call a heuristic technique.
Sounds pretty fancy, right?
Well, actually what it means is that I tried a bunch of different oils,
crossed my fingers and hoped that somehow it would work out.
And you know what?
It really did work out.
I was truly able to find
that some oils can restore the necessary properties of bitumen.
These oils can be produced from crude oil,
but they can also be produced from biomaterials,
and my favorite:
they can even be produced from waste cooking oil.
Just think of that.
We have lots of it in the fast food industry,
so each time when you go to eat your favourite burger,
you would be helping me to get the material that I need
to fix the road that takes you to that burger.
It's like a zero-waste cycle.
Actually, you can think of bitumen as a superhero.
You all know about Spider-Man and Batman and Superman ...
(Laughter)
and here, I'm introducing for the very first time ...
(Laughter) (Applause)
the incredible Bitu-man!
(Applause)
Well, his superpower is to keep our roads smooth and the rides safe.
But just like any good plot,
there has to be some challenge for the main character,
and for Bitu-man, his weak spot is his diet.
He has to follow a very strict diet.
If he's starved for oils, he will crack in winter,
but if we feed him too much of oils, in hot summer, there might some problems.
So he'll become soft and rutting will form in the wheel path of cars.
But the good news is that I have figured out his diet.
I know precisely how much of each oil to feed him
so that he would save our cars from punctures for many, many years.
And actually, let me tell you how I got from being a doctorate student
to, well, drawing superheroes.
When I first arrived the U.S., I wanted to blend in,
so naturally, I did whatever every good American does:
I bought an iPad.
(Laughter)
At the time, no one really knew what to do with them, including me,
so I watched some movies,
I browsed for some cat pictures over the Internet,
and basically, that was it.
But then, a couple of years later,
I was attending a German language course,
and I sat in a desk next to a student
who was using his digital pad for drawing some very nice images.
I thought, 'That's a pretty nice way to kill time. I should try it.'
So I went home, and I bought the stylus, you know, the digital drawing pen.
But since this was the first time since primary school
that I tried to draw something,
I drew whatever I was taught to:
a piano, a room and things like that.
But at the same time, I was attending a business school course,
and I noticed that some of my peers
were using this nice presentation software for demonstrating their results.
And at that point it struck me, you know:
What if I would draw my research and use this software for presenting it?
Surely, even my family would understand it.
And, you see, if I hadn't bought the seemingly unnecessary iPad
or gone to the courses that were in no way required for me to graduate,
I would have never been here on the TED stage with this presentation.
This kind of series of seemingly unrelated events
is actually why a 100% recycling is becoming a reality right now.
Many different technologies had to be advanced
before this was possible.
For example, the way that I found out
that oils can truly restore the elasticity of bitumen
was by using simulative test methods.
I was able to simulate a wheel path
with the small wheel running over a sample of asphalt for 20,000 times,
and I could also simulate cold weather or water damage,
but these are all new tests.
Even nowadays, pavement engineers rely mostly on empirical tests:
that is they know the characteristics of each material,
they know the ideal proportions,
and if they blend it all together at the right conditions,
asphalt should come out perfect every time.
But this is much like preparing a meal from a cookbook.
You chop and prepare all the ingredients,
you put them in a pot and serve your guests.
Well, without tasting beforehand, would you do that?
For a meal that you're preparing for the hundredth time,
perhaps this is fine, but what about a new dish?
And what if you would have to serve 100,000 people
and they would eat this meal for 20 years?
Well, this is precisely the situation with new technologies for asphalt.
We have to be very careful in what we deliver to our guests.
Hundreds or thousands of road users
will exploit the road for many, many years,
so we really want to taste the asphalt before putting it on the road.
And simulative test methods are of very good use for that.
You know the saying 'one picture is worth a thousand words'?
Well, pavement engineers have their own version of this:
One test is worth a thousand expert opinions.
OK, now we have the mixture recipe, we have learned the cookbook,
we can actually produce asphalt,
but again,
technological advances were required for this to become a reality.
And to explain the problem, let me tell you just a little bit
about the production of traditional asphalt.
To produce asphalt,
you have to heat the materials to a very high temperature,
something like 160 degrees Celsius,
and this has to be done so that stones would dry out
and our friend bitumen would become liquid.
During production, this is actually a good thing
because it kind of binds all the stones together, it glues them.
Bitumen is heated with electricity,
something you do at home to heat water in an electric kettle.
The stones, on the other hand, are heated with a direct flame,
and this is similar to heating marshmallows in a campfire.
Now think of reclaimed asphalt:
the stones and bitumen are blended,
so we have to keep them together for heating as well,
and we cannot use the electric kettle system
because this is not a liquid anymore, right?
But if we try to heat reclaimed asphalt with the direct flame,
bitumen starts to smoke and it can even ignite.
So the inventors had to come up with a new system,
a new technology that would allow to safely heat the old asphalt
without creating harmful emissions or causing flame.
Many different inventors have tried to tackle this problem
in the last 20 years or so,
but often, the most ingenious things in life are quite simple.
Just install a filter.
This is what Bob Frank did
for his pavement and asphalt plant in New York City,
and I was lucky to collaborate with him
to verify if the mixtures that we designed in the lab
would actually work in the field.
You know, a simple switch from an asphalt that was milled in Brooklyn
to an asphalt that was milled in Manhattan
might have meant that I would have to start everything over;
bitumen might have had a different taste for oils,
and I might have get stuck in the lab forever.
But you know what?
It really did work out.
We were truly able to produce 100% recycled asphalt,
and here you can see it being put onto the streets of New York.
It is just as black as any other mixture you have ever seen,
and when driving on it, you will never even know the difference.
And actually,
this was not the first site paved in 100% recycled asphalt
in New York City.
Already back 2001, an experimental site was paved using a pilot version,
a small-scale version of this asphalt plant,
and we went back there to take samples.
Of course, we drilled some samples in our new site as well,
and we tested them again with simulative test methods,
and the experiments confirmed that, if designed properly,
totally recycled asphalt can be by any means equal
to the one we're using every day.
Based on this positive experience and aiming for zero-waste recycling,
the city of New York
has allowed paving the city streets with such mixtures starting this year.
This is a huge breakthrough
because previously, there was a cap on the maximum amount of recycling.
And there you go:
we have created a zero-waste cycle.
We mill the old asphalt, bring it to the asphalt plant -
where I do the magic and decide what oils will keep bitumen happy -
and produce new asphalt using modern asphalt plants.
As you can imagine,
this is an environmentally friendly approach;
we are barely using any new materials
and basically, creating a closed cycle of recycling.
Every kilogram of reclaimed asphalt
will save a kilogram of non-renewable resources.
Oh, and one last thing: It is cheaper too.
Stones and especially our friend bitumen
are the two most expensive portions for production of asphalt.
But if we use reclaimed asphalt,
there is no need to buy these virgin materials
because we're replacing all of it with reclaimed asphalt.
And of course,
there are some additional costs for buying the oils
and doing the simulative tests and preparing the reclaimed asphalt,
but even with all of this included,
the productions costs for 100% recycling
will be up to 50% lower
compared to a traditional zero-recycled asphalt.
This means we can pave more roads with the same budget,
and perhaps, finally get back on track repaving those ugly potholed roads
wherever there is enough of old asphalt.
You know, I decided to specialize in asphalt
back at the time when I was working at a road construction company,
and I realized that some of my colleagues would suddenly disappear
precisely on the days we had to pave asphalt.
Someone had to go to the university or to see a doctor,
others had to do some urgent paperwork at the office,
but I thought, 'I've seen this somewhere,
this is what schoolchildren do on the days of tests:
They suddenly have their stomach aches out of nowhere.'
And asphalt paving actually is a lot like a test.
You really only get to do it once,
and people will see and judge your work,
especially if you fail at something.
Well, I thought, 'I'm pretty smart, I'm not afraid of challenges,
I can figure it out.
I'll read a couple of books, and I'll get all the glory
because everyone enjoys a nice and smooth ride.'
Fast forward ten years later,
after studying in three different universities
and many, many sleepless nights in the lab,
I think my colleagues are probably right skipping those days of asphalt paving.
(Laughter)
There is so much to learn about asphalt,
but with these drawings,
at least I tried to make clear the one thing that I do know:
Asphalt can be recycled into asphalt to create a zero-waste cycle.
So, the next time you are on a road trip with your friends
and someone spills a drink in the car because of the bumpy road,
ask your friends if they know:
Which is the most recycled material in the world?
Thank you.
(Applause)