Mona Shield Payne/Special to the Sun
Tuesday, May 25, 2010 | 2 a.m.
The potential future of American nuclear waste is again in Nevada’s hands — but this time it has nothing to do with under-mountain storage.
The U.S. Energy Department on Thursday awarded two UNLV research programs $1.45 million in grants. The works of chemist Paul Forster and engineers Jian Ma and Yingtao Jiang are among 42 research programs nationwide to receive money from the Nuclear Energy University Program.
The grants are aimed at boosting the efficiency of power plants and environmental protection in the industry and at solving key problems in nuclear waste reprocessing.
Nuclear waste reprocessing or recycling is the process of chemically breaking down the components of spent nuclear fuel so there is less radioactive material that needs to be stored and so reusable chemicals and compounds can be put back into service.
“We face serious energy challenges and we believe they create tremendous opportunities for us,” Energy Department spokesman Tom Reynolds said in a news conference announcing the grants last week. “Clean energy technologies, including nuclear, can increase economic growth while enhancing our energy security. President Obama and the Department of Energy believe nuclear is a key part of that. We want to revitalize the American nuclear energy industry.”
The two programs at UNLV will have two to three years to spend their allotments.
The announcement came as good news for the university, as it is struggling with deep budget cuts that some fear could roll back the gains the university has made in recent years.
Forster will receive nearly $1 million for fuel cycle research. His project will focus on separating two gases, krypton and xenon, that form during the fission of nuclear fuel. Separating the two will reduce the amount of waste nuclear power plants have to send to repositories. That’s because the type of xenon that comes out of the process degrades comparatively quickly, while krypton degrades far more slowly. Xenon’s radioactivity fully decays in about a year, but krypton takes about a century to lose its radioactivity.
Because there’s usually a lot more xenon than krypton in the mix, nuclear waste managers have to store significant quantities of a gas that, if separated, would not be dangerous. In fact, the isolated nonradioactive xenon could be sold to help offset costs. It’s used in anesthetics and lighting.
“The aim of our proposal is to develop a technology that can remove most of the xenon from the krypton that would also work well at a reprocessing facility,” Forster said. “Right now there isn’t good technology to separate them at the scales a reprocessing facility would need.”
Forster plans to test a gas separation process called pressure swing adsorption. That process is commonly used with other gases in other industries, but it hasn’t been tried for separating the specific gases for this problem in a nuclear power plant environment. Now that he has funding for the needed lab equipment and to hire qualified assistants, Forster believes he’ll have a working design material before the three-year study period ends.
“It’s not a particularly difficult problem to solve, but no one has looked yet,” Forster says. “I have several ideas of how to do this and create the necessary reaction in the compounds, but I need to be able to try new materials out and see if they work. If they do, I’ll be on the right path fairly quickly.”
Several yards away, in the campus’s mechanical engineering department, Jian Ma and Yingtao Jiang’s nuclear work is very different.
Jiang is an electrical professor and Ma is a research professor conducting molten metal coolant research. They will lead a group of researchers, including undergraduates and graduate students at UNLV and a team of community college students at Northern New Mexico College, in the attempt to create better, longer-lasting flow rate sensors for coolants used in nuclear reactors.
The engineers were awarded more than $451,000 to undertake the two-year project, which will consist of testing different metal materials and programming algorithms. Their grant is relatively small because UNLV has most of the equipment needed for their research.
In the first year, the researchers will start with water-based tests and then introduce the technology into a high temperature and corrosive environment in UNLV’s liquid metal testing lab. In the second year, they are to conduct tests at Los Alamos National Laboratory in New Mexico.
The research will help with power plant efficiency by cutting down on maintenance, Ma says.
“Having that information on the flow rate is critical for a power plant’s operation. This new technology will mean the (power plant operator) won’t have to shut down its power plant to do maintenance as often. We want something totally reliable and accurate.”
That’s easier said than done. These sensors must work in very high temperatures in a highly corrosive and radioactive environment. Designing one that will work for decades presents unique challenges, Ma says.