Texas Tech University

Engineers Developing Wastewater Technology for Use in Space

George Watson

June 7, 2016

Space

The group, along with partner Paragon Space Development Corporation, has constructed a way to efficiently and economically convert wastewater to drinking water.

Space

One of the most critical factors in long-distance space travel involves an element that doesn't even exist in space, and, for the time being, might exist on only one other planet.

Water.

Without enough drinking water, any attempt at a mission to the moon, Mars or anywhere else outside of earth's orbit, is virtually impossible. Yet, it's not as if astronauts can just load up a few cases of bottled water to take with them. Shipping large quantities of water into space becomes astronomically expensive.

For space travel to work, wastewater has to be recycled into pure, consumable water. That means a system has to exist on any space vehicle that carries travelers that converts wastewater in all forms into drinking water.

“NASA needs to close the water cycle to about 99 percent recovery to really make it economical and be able to live in space for long periods,” said Andrew Jackson, a professor and associate chairman of the Department of Civil, Environmental and Construction Engineering at the Texas Tech University Whitacre College of Engineering. “If you're talking about a mission to Mars or a lunar mission, it gets vastly expensive to ship mass up there.”

Water

That's where Jackson and Audra Morse, the associate dean for undergraduate studies and a professor in civil engineering, have focused their research for most of the past decade, developing a system that effectively and efficiently eliminates waste products from water so it can be recycled into consumable drinking water.

Partnering with the Paragon Space Development Corporation, their efforts received a boost recently when NASA awarded the group a Phase I Small Business Technology Transfer (STTR) award, totaling close to $150,000 to develop the Integrated Water Recovery Assembly (IRA) that can take wastewater and recycle it by reducing the need to pretreat wastewater with hazardous chemicals while eliminating the need for inefficient non-regenerable processes now in use.

“The big thing the award allows us to do is start working with Paragon to put a whole system together instead of looking at only one part of it and not being in control of what happens to the rest of it,” Jackson said. “We want to basically design the whole system and be able to deliver a package that does everything, from start to finish, and hopefully in the most sustainable and cheapest way possible. It lets the company and us start working together to see how we can maximize the attributes of both systems to work together.”

Two components

The system being developed by Texas Tech and Paragon has two distinct parts, but the idea is to develop them as a package deal which would be beneficial to both parties if chosen for use by NASA. It also would transform water more efficiently and use very little energy in the process.

STTR

The part Jackson, Morse and the team at Texas Tech have developed deals with more of a biological approach where microbes are used to separate elements in the wastewater like carbon dioxide and nitrogen for use in other areas. By doing so, the purification process developed by Paragon, which converts the water into drinking-water quality, wouldn't have to work as hard and would use up fewer consumable materials in the process.

The system has to be self-sustaining, Jackson said, so astronauts are not spending significant amounts of time with this process that could take them away from performing other scientific duties.

“The combination of a strong waste stream, microgravity compatibility and the ability to have someone taking care of it is a unique set of circumstances,” Jackson said. “We're working toward something that fits those constraints.”

Texas Tech's research is far enough along that it is running a full-scale reactor to test the recycling process, and Jackson said the Johnson Space Center in Houston is keeping a close eye on those results. A new reactor also will be delivered to Texas Tech in the near future to conduct more tests. Eventually, Jackson said, those reactors will be sent to Houston to be put into an integrated test with the post processor developed by Paragon to be put through rigorous testing to examine the process and study its mechanical functionality.

Space

If chosen, the reactor tested would be constructed out of flight-like materials similar to how it would be built on a space vehicle, but those materials are too expensive for the Texas Tech team to use on Earth. Jackson said there aren't many university research teams working on this kind of project and the ones that are focus mainly on reverse osmosis or forward osmosis technology.

“We are the only people I know who are doing bioreactor work for space habitation,” Jackson said. “We've been talking about a means to work together with Paragon for awhile and when this award came up one of the calls was specifically for water processing. Since they've worked on it and we've worked on it, it was kind of a perfect combination to work together. It was a synergistic proposal.”

Other uses

The IRA has other uses outside of space travel that could end up being just as important and economically feasible.

Because the system is fairly compact it can be dropped into regions where a disaster or other factors have eliminated an area's source of drinking water. The IRA would be ideal for use in the aftermath of hurricanes to ensure a supply of drinking water after a wastewater treatment facility goes down or is damaged.

It also could be used, Jackson said, in forward military operations bases in remote areas where water is a big concern and trucking it becomes a security risk.

“Anything like that where you have a limited ability to resupply technology, upkeep or technical power and you want something that is very self-sustainable that produces potable water, it makes sense,” Jackson said.

First things first, however, and that is getting this system ready for use in space, which means developing a system that is the most economically sustainable and efficient for use for whenever man tries again to reach for the stars.

Our proposal is that ours is the most sustainable, consumes the least amount of consumables and produces products that can be reused for beneficial purposes,” Jackson said. “It is self-sustaining. It is robust. We say ours has the lowest equivalent system mass. But that's what we have to prove.”