Environmental Control & Life Support System Help Astronauts Breathe

From pioneering systems that cooled the cabin and supplied oxygen on Gemini space capsules to the much more sophisticated Environment Control and Life Support System (ECLSS) on the International Space Station (ISS), Honeywell has made it possible for hundreds of astronauts to breathe, work and live in the vacuum of space.

Honeywell is proud of its six decades of achievements in environmental control and life support systems for spacecraft. But you haven’t seen anything yet, according to Phoebe Henson, Advanced Systems Engineer on Honeywell’s Human Space Research and Development team.

“We’re extremely excited to be working on systems that will sustain life as humankind ventures to the Moon and eventually to Mars,” she said. “The next-generation Space Exploration ECLSS for deep-space travel will need to be smaller, lighter, more reliable and more resilient to sustain astronauts on Martian missions that could last three years or more. Honeywell is on the front lines, working on a groundbreaking carbon dioxide removal system and other systems that will change human spaceflight forever.”

“It’s an enormous challenge,” she continued, “and I’m really proud of the work Honeywell is doing to enable history’s greatest adventure – travel to another planet!”

New technology for a new era in human spaceflight 

Honeywell and the other companies (including Precision Combustion, Paragon Space Development and Giner Labs) working with NASA on the new ECLSS technologies that are more than up to the challenge, said Ted Bonk, Honeywell Engineering Fellow for Space Applications.

“We’re ready to leapfrog the existing ECLSS technology that is still doing its job today on the ISS,” Bonk said. “But many of the technologies the current system uses have become obsolete over the last two decades and new technologies have become available, originating both from within and outside the aerospace industry.”

“The goal is to build on the success of current ECLSS subsystems and leverage newer technologies and components from aerospace and other industries,” he added. “That way we can meet NASA and commercial space requirements for future crewed missions to the Moon, Mars and deep space.”

The Space Exploration ECLSS will need to be flexible enough to meet the environmental and life support needs of NASA spacecraft scheduled to fly to the Moon this decade and Mars in the 2030s, as well as the commercial missions that are sure to follow. The subsystems must also meet the needs for long-duration installations and space vehicles including the Deep Space Habitat, Mars Transit Vehicle, Lunar and Martian bases, and future commercial habitats on the Moon and Mars.

Reliability is Job One for the Space Exploration ECLSS, Bonk emphasized. “We’re talking about setting up bases on the moon or another planet. The new system will need to be more reliable and self-maintaining because there will be fewer resupply missions than with the ISS. It’s simply not practical to routinely deliver supplemental oxygen to a Martian base or send a crew to the Moon to repair the carbon dioxide removal system.”

What does the ECLSS do?

Like the current system on the ISS, the Space Exploration ECLSS will clean the air by removing carbon dioxide, trace contaminants, particulates and microorganisms, and by generating oxygen from water and carbon dioxide. It also distributes and circulates the air at safe and comfortable temperature, pressure and humidity levels and eliminates odors.

“The ECLSS also recovers and purifies potable water from wastewater, condensation and extra-vehicular activity suits,” said Henson. “Honeywell provides a variety of components for various subsystems on both the current and future ECLSS. For example, Honeywell technology is critical to the Temperature and Humidity Control (THC) system on the ISS Columbus module, which creates a safe and comfortable cabin environment for astronauts.”

These essential and life-sustaining tasks are accomplished with a system using eight subsystems for air and water management on the ISS. For the new Exploration ECLSS, the current subsystems will be incrementally better versions that will boost performance and reliability of the overall system and deliver safety, health and comfort benefits for the next generation of space explorers.

As a result, the Space Exploration ECLSS will have lower volume, weight, power and cooling requirements. It will be more reliable and resilient, require less maintenance and crew attention, and will have a smaller resupply footprint than the current ISS ECLSS.

It also sets new performance standards include maintaining an extremely low CO2 partial pressure, which enhances crew safety, recovering 90% of water from urine and brine, which increases overall water recovery to better than 96% and enabling oxygen recovery from CO2 to better than 95%.

Honeywell develops game-changing CO2 removal & recycling technology

“We’re very excited about a game-changing technology Honeywell is pioneering called Carbon Dioxide Removal by Ionic Liquid Sorbent (CDRILS), which represents an enormous improvement in performance and efficiency, compared to the C02 removal assembly used on the ISS ECLSS,” Henson said.

The CDRILS system was specifically designed to remove carbon dioxide from cabin air on long-duration missions, she continued. “Simply put, the system uses an ionic liquid – essentially salt in a liquid state – to absorb the CO2 from cabin air. This process yields carbon dioxide and water as well as clean cabin air.”

New technology enabling better recycling of carbon dioxide is also under development.  The Honeywell Methane Pyrolysis Reactor uses extremely high temperatures to recover up to 95% of the oxygen in the CO2 taken from the cabin, far exceeding the 75% target NASA set for the process up from 50% recovery on ISS.

“Recovering this oxygen will reduce the amount of water required for oxygen generation on long-duration missions,” Bonk said. “That means a lot, since there’s significant cost associated with every pound the spacecraft carries. The CDRILS system is smaller, lighter and requires less power and cooling than the system it replaces.”

The carbon from CO2 is deposited onto substrates to form a clean carbon product that is durable and non-sooty. Honeywell hopes NASA can find a use for the carbon product, perhaps as a building material on Mars or the Moon.

The future is in Honeywell’s sights

Honeywell engineers have their eyes on the future, including the first human spaceflight to Mars, which is being planned for the 2030s.

“We’re currently building ground prototypes of the CDRILS system and other components in Glendale, Arizona, and Des Plaines, Illinois, and we’re getting ready to develop a flight unit that will be tested on the ISS sometime in the next three years,” Bonk said.

“I feel a lot of purpose in the work we’re doing,” he continued. “Space isn’t just my job. It’s also been my passion since I was a kid, so being part of Honeywell’s space business for more than 30 years is really living the dream for me.”