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Trash to treasure
Folks at MIT's D-Lab are turning trash into treasure - specifically, trash to heat homes and cook in developing countries. It's not magic - it's engineering!
Want to join the conversation?
- What is the "Binding Solution" used to bind the carbon powder into briquettes?(3 votes)
- Could there be an EVEN faster and cheaper method for producing Briquettes? If so, what exactly would be the more efficient method?(2 votes)
- Why would people treat the Earth bad enough to begin with?
\(?_?)/(1 vote)- It's means people producing a lot of carbon dioxide or CO2 which act like greenhouse gas making the Earth warmer and harder to live(1 vote)
- Were can you get you get a oil drum?(1 vote)
- how does it not burn into ash?(1 vote)
- Why p type semiconductor is positive charge carrier? Why n type semiconductor is a negative charge carrier?(1 vote)
- Are these briquettes more fragile than coal and do they make bbq taste different when used instead of charcoal?(1 vote)
- briquettes are made of charcoal in fact almost all charcoal is in briquettes(1 vote)
- If the difference of releasing the smoke in the lab when you can release it at home. Releaseing the smoke in the lab dose not make the briquettes any more eco friendly right?(1 vote)
Video transcript
Corn husks burn quickly
and turn to ash. These lumps burn hot like
firewood, longer than charcoal, but are cleaner, greener,
and less expensive than both. This is actually made from this. And I'm going to show you how. [MUSIC PLAYING] About three billion
people in the world use charcoal today to heat
their homes and cook their food. But charcoal can be expensive. It produces a lot of
smoke when burned, and it's made from wood, which
contributes to deforestation. In fact, 98% of Haiti's forests
have been cut down for fuel. What we need is an
alternative fuel source. Let's take a look at
how charcoal is made. We have to first cut down
trees for wood, which we then place in a closed vessel
and deprive of oxygen. It carbonizes into charcoal
instead of burning to ash. We then mix the charcoal
with a binding solution and compress that into
lumps called briquettes. This process creates
a fuel source that works, but has its problems. So let's hack the charcoal
production process to make everything about it better. Part of what makes the
charcoal process so expensive is the equipment. Instead of a fancy
vessel, you can make a simple kiln
out of an oil drum by cutting a large hole in the
top and several smaller ones in the bottom. Gather a couple of large
rocks for the kiln to rest on, a lid for the top, and you
have yourself a $15 kiln. We also need some kind of tool
to mold the charcoal material from the kiln into briquettes. This is one of D-Lab's earlier
designs for the hand press. We pour a mixture of charcoal
and binder into the spout here, hammer down the piston, slide
open the panel at the bottom, and the briquette
pops right out. This design costs about
$20 to manufacture. But the engineers at
D-Lab wanted to do better. They changed the shape of
the mold into a square, to make it easier to manufacture
and significantly cut down on the amount of material used. This time, the mold itself is
used to scoop the charcoal. Again, we hammer the piston, and
the briquette pops right out. This design is easier
to manufacture, it creates briquettes faster,
and it only costs about $2 to make. Now that we've made the
equipment less expensive, what can we do about
making the fuel cleaner? If we can get all the smoke to
burn off while the charcoal is being made instead
of being used, we can decrease
the amount of smoke released in people's homes. Leaving the kiln open
for about five minutes at the beginning of the
process will allow the smoke to burn off outside. So that why we cut a hole
in the top of the oil drum. All right, final challenge. What can we do to make
this fuel more sustainable? What if we replace the wood
with something else-- something like dried corn husks
or dried corn cobs, dried beanstalks, or
even dried banana peels? These agricultural waste
products, or ag waste would normally be
discarded as trash. But we can use them to
make charcoal, and poof! Your trash becomes
a precious resource. And that's how you turn trash
into treasure-- less expensive, cleaner burning, more
sustainable treasure.