New Nanomaterial Takes the Stink Out of Submarine Air

New Nanomaterial Takes the Stink Out of Submarine Air

Desperate for a breath of fresh air.
David C. Duncan/US Navy
On a US Navy submarine, every breath you inhale has been repeatedly exhaled from the mouths of about 120 other people. This isn't as suffocating, or gross, as it sounds, because submarines have ventilation systems that take the CO2 out of the air, and recirculate it with chemically catalyzed oxygen.

I take that back, the air is gross, because the chemical used to remove CO2 smells like old diesel mixed with a dash of sulphur, and it permeates everything on board. This chemical, called amine, is known by every submariner (I was one for 3 years), as well as every submariner's wife, husband, or anyone else who encounters that sailor's laundry. However, a new CO2-capturing nanomaterial could bring an end to this most notorious of submarine smells (trust me, there are others).


This is how the CO2-binding molecules coat the sand grain's pores. Look at 'em there, sucking up all that CO2!

Pacific Northwest National Laboratory
Unlike amine, which is a liquid, the new material looks like sand. In fact, it is sand, except it is covered with tiny pores, each filled with molecules that selectively pull CO2 out of the airstream. Together, sand grain and molecule are called Self Assembled Monolayers on Mesoporous Supports, or SAMMS. The pores create nooks and crannies that let even a small amount of the material soak up an incredible amount of CO2—a teaspoon of the material has slightly less surface area than a football field. And it's reversible. "With a slight amount of heat, you can also open that molecule back up and release the CO2, making it possible to use the same material over and over again," said Ken Rappe, an engineer at Pacific Northwest National Laboratory who worked on SAMMS.

There are many different types of SAMMS, each designed to bind with a specific molecule. They were originally engineered to pull mercury and other contaminants out of industrial waste streams, Rappe says. The CO2-binding version was identified by accident over a decade ago, when a scientist accidentally dropped a sample of the stuff in a glass of water. The sample started fizzing. Some experiments showed that this fizzing was the water dissolving stored carbon. At the time, carbon capture and storage wasn't a huge research interest (besides, SAMMS likes its CO2 cool, and coal power emissions or automobile exhausts are too hot to capture), and the researchers searched for an application before a colleague pointed them to the problem of funky sub air.

Amine doesn't just stink, it's also highly corrosive and will ruin anything not made of stainless steel. This makes it a huge maintenance burden, as it needs to be flushed and moved into storage whenever it gets saturated with CO2. The sandy SAMMS would alleviate this, as it doesn't need special storage. "When you go from a liquid to a solid, you're able to get rid of all the pumps and tanks," said Jay Smith, an engineer at the Naval Ships Engineering Station, Naval Surface Warfare Center Carderock Division (NAVSSES) in Philadelphia who has been getting the SAMMS-based replacement ready for deployment. "It's also safer, and more environmentally friendly to dispose of," she said.

Changing out life support equipment on a submarine isn't trivial (no matter how reviled the piece of equipment). Rappe and his research partners spent years improving the material before turning it over to the Navy. Since then, Smith and her colleagues have been testing the prototype SAMMS ventilation system specifically for submarines. She says the prototype is currently going through long-term testing with lab-simulated sub air. It could then be deployed on future submarines joining the fleet. Smith also noted that the SAMMS technology has already been evaluated successfully at sea through small scale test units.

And as long as the Navy's switching out gear on the sub, how about a margarita machine in the crew's mess?

 

No matter how you cut it all submarines smell about the same about two weeks after a major overhaul or commissioning. Be they Nuke or Diesel.

 

A non-alcoholic margarita machine surely.....I thought the USN was 'dry', thanks to


A Hundred Years Dry: The U.S. Navy's End of Alcohol at Sea - USNI News

The nano particle-technology for air scrubbing will be a welcome breath of fresh air for many.

 

I know that recycled air is not "fresh", but you also know that a "breath of fresh air" is a figure of speech.

It makes sense to have an auxiliary diesel-electric power plant...in case of nuclear power plant shut down, in an emergency, or during reactor maintenance.

 

Glad I served on an ASW frigate. Subs to us were simply "targets". But, we had our smells too.

 

In AMR2 for me.
O2 Gen and scrubbers in AMR1

 

Have often thought about some system to bridge the period when air to a shelter might be contaminated by smoke, contamination, infectious agents, etc. Have ability to cool incoming air with well water, but only filtering of the air and that is limiting. Have non medical oxygen for welding and with co2 scrubbers, might be able to lock down for a short period, but my knowledge of monitoring and control of scrubbers prevent me from even trying to do so.

 

Better to get a hand cranked Bio Hazard Filter'
NBC Air Filter - The Safe Cell from American Safe Room

 

I used to save my Beer's and trade them got great stuff for a little beer

 

Cramped! 688 Class

 

So , if you have an under ground bomb shelter this might be valuable ?

 

We used Amine to strip H2/S and Benzine from Nat.gas, It worked to a certain extent but I believe it camouflaged it to a minimum %.

 

After reading this it makes me happy to have been on a Tin Can!