It smells.
It gets on you.
But that's okay because to me urine is exciting.
This is William Tarpeh, an Environmental Engineering PhD student from UC Berkeley.
His field of study basically harnesses the principles of engineering, biology, and chemistry
to develop solutions to problems that negatively affect our environment.
So Environmental Engineers tackle things like air pollution, contaminated water and reducing
garbage waste.
But like with any field, there are outliers.
Like Will.
Will spends all day, every day, transforming pee into liquid fertilizer, attempting to
spin gold out of something that the rest of us flush away without a second thought.
I mean.
It's gold in color but… it's also valuable.
I'll just let him tell you.
We focus on the nitrogen in urine because it's in fertilizers that people buy and it's
also in urine.
Our big idea is to extract the nitrogen preferentially out of urine into a product that we can sell.
Now, Will doesn’t plan on becoming the world’s first pee-millionaire.
Uriillionare?
Anyway, his motivation for making pee profitable is actually toilets.
Because while basic sanitation is something that many of us in the West take for granted,
for 2.4 billion people around the world, it’s a very real public health issue.
...sanitation to me is really fundamental.
It affects so many parts of life that we don't think about.
The big purpose is to find ways to make sanitation self-funding.
That's the really big idea; how can we create value from something that's normally waste
and in doing so generate the money that will help us proliferate more toilets, help us
build more toilets.
To build toilets you need money, so you need a product to make dat money.
Fertilizer contains nitrogen, phosphorus and potassium, all chemicals that are naturally
found in your pee.
So, for four years, Will has been working on transforming regular old urine into a nutrient-rich
fertilizer.
Of course, in order to do that, he needs a steady stream of pee for his research …
When I'm here in Berkeley we have to file paperwork to basically get urine from my lab
mates.
We're a pretty enterprising bunch.
We're environmental engineers.
It's not a hard sell….
Once Will has collected enough, he then has to let it sit for one week… he called it…
"curing" *disgust face* Amazing.
... when we excrete urine, the nitrogen is present as something called urea.
That's an organic compound.
Then throughout about a week's time, that gets hydrolyzed, meaning in the presence of
water and an enzyme called urease, that urea gets turned into ammonia,...
That's our starting point because the ammonia we can work with.
It's more mobile.
Ammonia is a compound of hydrogen and nitrogen, but as it’s still mixed up with lots of
other chemicals present in uc-rine, so Will had to develop extraction methods in order
to isolate the valuable nitrogen to make it into fertilizer -- so far he’s created two.
The first method is called electrochemical stripping.
Will uses an electrochemical cell with three chambers that can selectively filter nitrogen
out of the urine.
This is how it works: Pee goes into the first chamber.
Then, into the middle, goes a really dilute salt solution.
When electricity passes through the electrochemical cell the ammonium, which is positively charged,
is pushed through a membrane -- out of the pee and into the salt solution.
There we've selected first for charge.
Then we get things like ammonium, sodium, and potassium.
We've gotten just 3 things out of the urine.
Now our job is not done.
We still have to get just the ammonium out.
So once the pee party has moved into the middle chamber, the electrical charge forces the
solution to form hydroxide ions.
This changes the nitrogen from a liquid to a gas which moves allows it to move into the
third chamber.
The gas is then mixed with water and voila - liquid fertilizer!
The second method seems to be a bit more efficient.
It's called an ion exchange column.
Basically, it's a tube filled with a resin material that is negatively charged….
Think of it like a water filter.
The nitrogen is part of the ammonium, which, by the way, is positively charged so…
We pass urine through a column, this time the nitrogen goes onto the resin beads, those
spheres, and then the rest of the urine passes through.
Now we can take a really dilute acid and pass it over those resin beads and now the nitrogen
will go back into solution.
Now, this all works perfectly well in the lab, but Will wanted to see if his innovations
could work in a real world setting - somewhere where sanitation is a real problem.
So he partnered with Sanergy, a company that build toilets in the slums of Nairobi, Kenya.
Sanergy already collects feces and turns it into fertilizer, but before Will’s innovations,
they were disposing of thousands of liters of urine EVERY DAY.
This past summer we were actually testing both of these technologies side by side and
doing it in the field with real urine that's collected every single day.
I love being in the field, and for me I like being close to the people who use the technology.
I like looking at the toilets and seeing, okay, how would I actually use this?
That changes your design process so much.
And after testing his innovations in Nairobi, Will is definitely thinking about the future.
The biggest challenge -- how to turn those thousands of liters of urine into fertilizer.
[WILLIAM] I'm really good at doing this in lab on my
small filters and my small test kits that I've built, but then it's how do I make this
big enough to treat 5,000 liters of urine a day in comparison to right now we treat
about 5 liters a day.
how do we scale up the costs of making sure the process still works at the same efficiencies
that we've gotten it to work at in the lab?
If Will is able to scale up his idea, his work could help transform the lives of billions
of people on the planet.
I wanted to do things that had environmental implications and that had impacts on people's
lives.
Combining those 2 things, it's no surprise that I ended up doing environmental engineering
and basically ended up researching the chemistry of urine.
Yeah, those are the things that excite me, but I think it's really how I can bring my
training and my passions to bear on an important problem.
We want to take a moment to thank our partner the Blum Center for Developing Economies at
the University of California, Berkeley, an innovation and research hub that is tackling
issues in global poverty.
Make sure to check out some their incredible work by visiting blumcenter.berkeley.edu.
Technology is really changing life in the developing world.
For example: now cell phones can be used as hand-held microscopes to diagnose malaria
in just 30 seconds!
Want to know more, check out this awesome video from Seeker Stories.
We've all heard, one man's trash is another man's treasure, right?
That's totally this story.
Have you ever reused something that was once trash?
I found a great couch in the garbage once.
Let us know in the comments.
Make sure you come back here for more DNews and thanks for watching.