National Geographic - UK (2019-07)

(Antfer) #1

Rotating


flush bowl


Membranes


Drying


chamber


Liquids


warming coil


Clean water


Holding


chamber


NEW PLACES TO GO


A TOILET IS LIKE A “SUPER VACCINE,” says Doulaye Kone of the Bill &


Melinda Gates Foundation. “It kills disease where it is produced.”


Traditional sanitation systems are costly to build and maintain, so


the foundation’s Reinvented Toilet initiative is helping to develop


alternatives such as the toilets seen here. Safe and inexpensive to


operate, these commodes can function without running water and,


in some cases, electricity. They’re also sustainable, eliminating


pathogens while recovering nutrients and energy.


The Nano Membrane Toilet is


a portable, self-contained unit


that doesn’t require external


power. Waste is mechanically


separated. A combustor dries


and burns the solids, while


liquids are heated and puri-


fied. The resulting sanitized


ash and water can then be


removed for safe disposal.


MECHANICAL DRY


BIO-COMBUSTION


Lowering the lid rotates


the bowl and activates


a blade that scrapes


waste into a tank.


Dried solids fall into


the combustion


chamber, where a self-


sustaining burning


cycle turns them to ash.


The purified vapor


condenses into


water, which flows


into a tank that also


serves as a footrest.


An Archimedes’


screw moves solids


into a drying chamber.


Liquids are heated into


vapor that is filtered


through membranes.


The ash—as


much as 100


grams a day


for 10 users—is


emptied daily.


THE PROCESS TAKES


LESS THAN 24 HOURS


TO COMPLETE.


1


3


2


Untreated water


Solids


Treated water


USERS


PER DAY


10


YEARS’


LIFE SPAN


10


ILLUMINATING THE MYSTERIES—AND WONDERS—ALL AROUND US EVERY DAY


NATIONAL GEOGRAPHIC VOL. 236 NO. 1


EXPLORE


IN THIS SECTION


Storied Boots


A Salty Swim


Argonaut Sacrifice


Firefly Forest


NANO


MEMBRANE TOILET


HTCLEAN


TOILET SYSTEM


30 NATIONAL GEOGRAPHIC

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