Small Inputs, Big Impacts

Paige Novak

"I work with bacteria that eat pollution, the potential is huge!"

Although she can state it simply, Professor Paige Novak's research uncovers mysteries of bacteria too small to see with impacts too big to ignore. Here she explains a bit more about her research.

HYDROGEN FROM WASTE

Currently, what happens in a wastewater treatment plant is that we take the energy-rich material that comes in—wastewater has a lot of chemical energy associated with it—and we expend a lot of electrical energy to get different kinds of bacteria (aerobic, oxygen breathing bacteria) to consume that waste and make CO2.

Professor Bill Arnold and I designed a membrane module where bacteria are encapsulated into a polymer and produce hydrogen gas from wastewater. Basically we take waste, generate hydrogen from it, capture it, and put that energy into a usable flow.

Technology development is not an area that I normally work in, so developing this module has been exciting and fun!

Capturing the hydrogen turns out to be the tricky part. We’ve designed our module so we can collect the hydrogen gas at the same time the bacteria make it. After that, fuel cell technologies can be applied to use the hydrogen to generate energy. Our new technology also uses anaerobic bacteria, which means we do not have to expend energy to give the bacteria oxygen— that is a different approach than what has been done before.

It has been really successful so far. Our calculations are made with the optimistic-but-not-crazy assumption that we can access all the waste. Optimistically, our calculations show that from the waste of a treatment plant, we could generate 10 times the amount of energy currently used by the plant. Our module has the potential for a dramatic impact on the field—if it pans out.

This collaboration between Bill and I came about pretty naturally; in the department we often talk about the work we are doing. I have done a lot of research on bacteria degrading pollutants; that is my primary area of research. And I have done—and still do—a lot of research on bacteria degrading PCBs (polychlorinated biphenyls) and other chlorinated compounds. That work is intensely microbial: figuring out which bacteria do what and how they do it, what the bacteria are consumer, the effects different chemicals have on them--the nitty-gritty stuff of biology

Bill had been working on passive membrane barriers, putting compounds in the polymers that would react when harmful chemicals diffused through the membrane. He thought, “If we could put Paige’s bacteria in the polymers, and layer chemicals with bacteria, maybe we could do a better job, maybe the membranes could be more effective.”

So he and I did that and it worked. We had bacteria in the membrane eating PCBs as they diffused through the membrane. Then I proposed we put bacteria that make hydrogen into the membrane. But we had to find a way to remove the hydrogen so other bacteria wouldn’t eat it before we could use it; hydrogen is like candy to them! Bill had the idea to insert tubes into the membrane to whisk the hydrogen away. That allows us to pull the hydrogen out of the system so that we can use it.

A three-year grant from the Legislative-Citizen Commission on Minnesota Resources (LCCMR) has supported a lot of our work. We now have a patent filed on the idea. We are also starting to work with another encapsulation researcher from mechanical engineering here at UMN, Alptekin Aksan. We are working on a new patent with Aksan on a similar idea, with a new twist.

It has been fun thinking about technology development, and it has led to new collaborations!

LEAKY CELLS

I have always tended to look at what bacteria can do to chemicals, for example, bacteria eats chemicals. I am working on a project with Tim LaPara to look at the effects chemical mixtures have on bacteria.

"This is a new perspective!"

A lot of time and a lot of money are put into getting bacteria to degrade waste in wastewater, landfills, or natural systems. If we can better understand how chemicals affect bacteria in those processes, we could head off some problems that arise.

Other researchers have seen that perfluorinated compounds can get into the membranes cells and make the cells “leaky” (that is, let chemicals or compounds in and out through the membrane). Cells probably do not suffer a huge, general leakiness, but probably something more chemically specific.

So Tim and I are wondering if leaky cells are more susceptible to other chemical insults. And then we want to know which perfluorinated compounds might induce leakiness, at what concentrations, and which cocontaminants (other chemicals) would likely get led into the leaky cells. One of the questions we are researching is “does leakiness of the cell lead to more antibiotic resistance?” (See a brief discussion of this work. http:// cse.umn.edu/admin/comm/features/ CSE_CONTENT_472679.php)

We have been working in this area for a few years. My colleague, Matt Simssik in Public Health, and I just got a new 3-year grant (started July 1). We are hopeful that we will be able to nail down these questions in that time. I have a graduate student working with me in this area, and this summer, I also have a high school student working in this area. It is always fun to have students working in the lab, fun to watch as they begin to see the reality of science and what it can do.

STANDING COMMITTEE ON CHEMICAL DEMILITARIZATION

I was contacted a couple years ago to serve on a National Research Council study committee. Committee members were to look at a plant designed to treat chemical weapons and suggest things to look for during systemization, a period of testing to make sure the plant would run well once it “went hot,” as they call it. After that study, I was asked to serve on the standing committee, a group that meets twice per year to hear updates from the two remaining facilities. We provide advice, point out things to think about, and decide if additional study committees are needed to look at a particular issue.

Prior to my involvement in the National Research Council’s Standing Committee on Chemical Demilitarization, I was not aware that the US still had chemical weapons.In fact, 90% have been destroyed and about 10% of the original stockpile is left. I am on a committee that gives feedback on the process of getting rid of the last of those chemical weapons.

Most of the stockpile has been destroyed by incineration. In 1997, a law was passed stating that the US could not incinerate chemical weapons at two of the stockpile locations, so those locations had to find other means of disposal. These last two plants have a lot of first-of-its-kind equipment which, obviously, hasn’t been used to destroy chemical weapons before.

It is interesting to think about these chemicals as just another pollutant, and to consider how everything one knows from a fundamental perspective—about how bacteria work, how reactors work, and how to design a reactor to do certain things—is all relevant to looking at this strange stuff.

JOBS AND A CLEAN ENVIRONMENT

I am co-directing a MnDRIVE Initiative called Advancing Industry, Conserving Our Environment. Our goal is to find a way to embrace progress and environmental protection. We need to find a way to have both together, although they sometimes seem counter to one another. (Read about MnDRIVE http://mndrive.umn.edu/.)

We think of ways to support and stimulate research that will have a positive impact on the environment and on industry. We want to support industries that hire Minnesotans, like agriculture, mining, or other industries. Our efforts have a microbial slant, using microorganisms to clean the environment, with a primary focus on water in agriculture, industrial waste, municipal waste, and mining. We’ve funded a couple of demonstration projects that are working on larger scale treatment, and we’ve also funded more basic research.

EARLY INTEREST

I really got fascinated in the early 80s when an oil spill was in the news and a superbug was being developed to degrade the oil. I found it so fascinating! Somehow this idea of tinkering with bacteria to solve this big problem resonated with me. My dad was a professor of environmental engineering, so I knew that this was a job that you could have.

As a kid, I was either going to be an artist or an engineer. Those fields may seem incompatible at first, but all research is, at its heart, very creative. That is what really resonates with me: the excitement of being creative, of coming up with a wacky idea to solve a problem, to save the world! To make hydrogen from waste! It is a cool thought!

As an engineer, the thing that comes first to my mind is “how can I apply this, how can I fix this problem?” I love to play around with bacteria in the lab and look at the data. I like to figure out all the nitty-gritty science, but for me, the main drivers are always, ‘how can we apply this?’ and ‘how can we solve this problem?’

NEW MAJOR IN ENVIRONMENTAL ENGINEERING

CEGE’s new EnvE major is a good thing! There is a lot of interest in environmental issues, which is great, and we have specific knowledge that will help students practice environmental engineering when they graduate.

It seems pretty easy to connect environmental studies coursework with reality, but students might not make connections as directly on their own. Learning to set up a mass balance could seem dry and unimportant, but it is really critical. It is important to help students make those connections. I’ve even been able to bring some of my recent experiences with the chemical demilitarization committee into my classes to help students think about how we can apply general, fundamental knowledge to something strange and new that we haven’t thought about before.

There are not that many environmental engineering programs throughout the country. As news of our new name and our new major percolates out, more people will come to UMN for environmental engineering. The new program will also highlight our existing geoengineering major, as people become aware that we offer three different majors. (CEGE offers majors in civil, environmental, and geo- engineering http://www.cege. umn.edu/prospective/undergraduate/ index.html).

UMN is a huge university, which can be daunting, but it also means there are amazing resources here. Students just need to nose around a little and they can have incredible experiences here. CEGE is a great place to be!

Back to Magazine

Share