UF Air Revitalization Research shows promise For Manned Mars Mission

August 20, 1998

GAINESVILLE — With hermetically sealed walls and numerous life support systems, space craft are intended to protect astronauts from deadly conditions outside.

But the high-tech cocoons can become dangerous or difficult to work in if the air occupants breathe becomes contaminated. Scientists and engineers have devised methods to guard against the problem on short space flights or aboard space stations, but air revitalization ranks as a major technical challenge for extended missions such as a planned trip to Mars next century.

Now, a University of Florida chemical engineering professor is reporting early success with a revolutionary new technology that could one day remove deadly carbon dioxide and other harmful gases from air on a Mars-bound vehicle or on Martian or lunar colonies.

“We think there’s a lot of potential here,” said Ranga Narayanan, a specialist in fluid dynamics and applied mathematics at UF.

NASA uses chemical and filtration methods to purify air on space flights, Narayanan said. Space stations also replenish air revitalization equipment with supplies flown in from Earth. A Mars mission requires new technologies because transporting the amount of chemicals and filters needed for the estimated six- to nine-month trip, 500-day stay and six- to nine-month return trip would be impossible or very expensive, Narayanan and NASA officials said. Resupply from Earth, meanwhile, would be impossible.

Funded with a $230,000 grant from NASA, Narayanan and several chemical engineering graduate students designed, built and are testing a machine that could revitalize air on long missions or planetary visits without chemicals, Narayanan said.

The stainless-steel-and-aluminum machine works by separating gases through “oscillating flow,” or moving them back and forth in closed chambers, Narayanan said. The concept was pioneered by Mark Jaeger, a UF professor of physiology, and Ulrich Kurzweg, a UF professor of aerospace engineering, mechanics and engineering science, he said.

The researchers pump precisely measured doses of gases into two sealed aluminum chambers connected by a hollow metal tube. A machine moves the tube back and forth at varying speeds, with the researchers measuring changes in the gases.

Narayanan said the device had successfully separated large proportions of carbon dioxide from helium in one chamber and transferred the gas to the other chamber, an indication it could remove carbon dioxide or other gases from air. Any remaining carbon dioxide could then be removed using filters or other technology, he said.

“The advantage is you don’t need to treat large volumes of diluted gas,” he said. “You can now treat lesser volumes of more concentrated gas, so you’re saving energy.”

Much remains to be studied before the technology could ever be used on a Mars mission, Narayanan cautioned. Besides confirming the device will work with air, researchers also must determine how much energy it may require, how heavy it will be and whether it would continue to function in a low-gravity space environment, he said. Negative results on any of these steps could scuttle the idea, he said.

Narayanan’s machine is one of several air revitalization alternative technologies NASA is pursuing, said Guy Fogleman, lead for advanced human support technology in NASA’s Office of Life and Microgravity Sciences and Applications in Washington, D.C.

Fogleman said the office’s goal is to cut down the materials and equipment needed for survival in space, reducing the cost of a trip to Mars and making it more practical.

“For every pound I send to Mars, I’m going to need 40 pounds in low earth orbit, and it takes a lot of energy to get the 40 pounds up there,” Fogleman said. “Our goal is to reduce the overall mass required per person per year by a factor of two or three.”

New technologies resulting from the NASA office’s efforts also could prove useful for the planned International Space Station, Fogleman said.

“If I can increase the amount of time needed between resupply missions, it would make the station more self-sufficient,” he said.