This article is more than 1 year old
New tech lets you drink exhaust fumes
Handy in Afghanistan – or in an airship
The other neato thing about this so-called Transport Membrane Condenser tech is that the ceramic micropores also act as a very effective filter, removing all the contaminants found in diesel exhaust and producing nice clean water.
DeBusk seems to hint that the ceramic water-making kit needn't be installed solely at electrical generator plants. She points out that a Humvee-tankful of diesel could also yield a day's supply of water for three soldiers, suggesting that US military vehicles might be able to make drinking water for their crews in future.
It's all an intriguing idea, then, right enough – but what's all this got to do with airships?
Well, as regular dirigible-fancying readers will know, one of the main problems with helium-filled blimps (or rigid ships as in the great days before the Hindenburg disaster) is that as the ship flies along and burns fuel it gets lighter. As the airship becomes more and more buoyant it will not only become more or less impossible to bring it in for a landing – after a while it will rise through its "pressure height", where the lifting gas has expanded to fill the entire envelope. Gas will then be lost through safety valves designed to prevent the ship bursting.
Helium being expensive stuff, it isn't acceptable to vent off gas (or lose it during excursions above pressure height). Thus, helium ships intended to make longhaul flights have generally had to have some means of dealing with increased buoyancy due to burning fuel.
In the 1930s the US Navy's mighty aircraft-carrier dirigibles and the German Hindenburg and Graf Zeppelin II* were all designed with condenser-type machinery intended to recover water from their engine exhausts, rather in the fashion of the "undeployable" equipment recently rejected by the US military. This kit, which naturally had to dump heat into the air passing by the ships' hulls, was heavy and took up capacity which could otherwise have carried more fuel or payload. It was also troublesome and difficult to maintain in operation.
The modern fashion is for "hybrid" airships which are meant to operate in a heavier-than-air condition, aided by vertical thrust from their engines or lift from their hulls moving through the air. These ships have no need, perhaps, to accumulate water ballast to make up for burned fuel.
At least one modern contender, however – the Bullet 580 ship about to go to work for NASA – uses "water condensate" methods to control its buoyancy. Other non-hybrid designs such as the Zeppelin NTs – successors to the great zeppelins of old – might find the new capillary-action water recovery tech to be of use, especially if it really can be made small enough to go on Humvees.
So airship fans might also find the new microporous ceramic technology interesting, as well as watchers of cunning military solutions.
Definitely one to keep an eye on. ®
*LZ-129 Hindenburg was designed and intended to be helium filled. In the event the US government, controlling the entire world helium supply, refused to furnish any to the Nazi regime and she was filled with explosive hydrogen.
LZ-130 Graf Zeppelin II which followed the Hindenburg, was also meant to be helium filled: her water-recovery equipment was thought to be the best yet developed at that point. However she too wound up filled with hydrogen. After the Hindenburg disaster, the German authorities refused to allow her to carry paying passengers and she had only a short flying career before being broken up for her aluminium.