Washington University seeks solutions to global energy challenges

Because it emits carbon dioxide, the most abundant of greenhouse gases, coal has its detractors, but also a growing cadre of researchers seeking ways to capture the gas and then permanently sequester or store it in numerous safe havens, such as in underground saline formations or depleted oil fields.

Visitors saw the new Staged, Pressurized Oxy-Combustion (SPOC) facility last spring.

Coal produces 40 percent of the world's electricity, whereas intermittent energy sources, such as wind and solar power, while growing in recent years, together account for 4 percent of global electricity.

In 2009, the Consortium for Clean Coal Utilization (CCCU) launched at Washington University in St. Louis, under the umbrella of the International Center for Advanced Renewable Energy & Sustainability (I-CARES) to create a strong research base and infrastructure to devise the wisest, cleanest ways to use coal and dispatch the carbon dioxide emissions problem. Initially sponsored by Arch Coal, Peabody Energy and Ameren Corp., funding for the CCCU was recently extended for another five years. Total funding since 2009 is $15 million over 10 years.

At its inception, the university had two researchers with coal projects. One of them, Richard L. Axelbaum, the Stifel & Quinette Jens Professor in Environmental Engineering Science, became director of the CCCU, as he is today. At the time, federal funding for coal research at WashU was roughly $100,000 annually. Today, CCCU has seven faculty researching coal with numerous others supporting them. Seventeen national and international collaborators have joined the core faculty in projects, and government funding in 2014 was nearly $2 million. No fewer than nine international institutions, including the Indian Institute of Technology, Peking University, University of Indonesia and Darmstadt University of Technology, have partnered with CCCU through connections enabled by the university's McDonnell Academy Global Energy and Environmental Partnership (MAGEEP).

"The Consortium recognizes that coal is an invaluable global resource and yet carbon dioxide emissions from coal combustion are a global concern," Axelbaum says. "At the same time, the intermittency of wind and solar is not a viable approach to a stable electricity supply. Coal is ubiquitous and has the feature of being available in all places at all times. This availability, which is geopolitical stabilizing, leads to economic growth and a better quality of life. Geopolitical stability can exist when a country doesn't have to rely on other countries for its lifeblood — energy."

In 2013, Washington University became the only university in the United States to be asked to join the U.S.-China Clean Energy Research Center (CERC) after it was formed. President Barack Obama and Hu Jintao, former general secretary of the Communist Party of China, created the Clean Energy Research Center (CERC)-Advanced Coal Technology Consortium and two other CERCs in 2009 — one in transportation and the other in buildings.

"In terms of supporting joint research on coal between Chinese and U.S. universities, primarily there is just the CCCU and CERC," Axelbaum says.

Presently, there is concern about the high cost and low efficiency of carbon dioxide capture, Axelbaum says. The CCCU is addressing this by constructing a three-story, high-pressure facility in Urbauer Hall made possible by the U.S. Department of Energy and CCCU partners' funding. The Consortium's Advanced Coal & Energy Research Facility (ACERF) supports the development of new technologies to capture carbon dioxide from power plants.

A basic problem with carbon dioxide capture is the high amount of nitrogen in air, Axelbaum says.

"In a power plant, most of the flue gas is nitrogen, so you can't just take flue gas and pump it underground," he says. "You can either remove the carbon dioxide from the flue gas, which is rather expensive, or you can remove the nitrogen from the air, so when you're done, you have just carbon and oxygen, making CO2, which can be pumped underground. We're developing a system that lets power plants burn coal in pure oxygen without getting a meltdown of the boiler."

The system, which Axelbaum and his team are developing, is called Staged, Pressurized Oxy-Combustion (SPOC) and has been proven in principle in Phase 1 and is now in Phase 2. Its success has drawn interest worldwide. The U.S. Department of Energy (DOE) has provided $4.2 million to support its development, and in September 2015 provided another $1 million, with nearly $300,000 in cost sharing from the CCCU and the School of Engineering & Applied Science, to develop a more efficient technology to recover latent heat and remove the sulfur oxides (SOx) and nitrogen oxides (NOx) from flue gas during pressurized oxy-coal combustion. SPOC's development and others would have been impossible without the CCCU funding and cost sharing, Axelbaum says.

Of the seven WashU faculty active in CCCU, two faculty members from Energy, Environmental & Chemical Engineering have become major forces in coal research. Young-Shin Jun, the Harold D. Jolley Career Development associate professor in Energy, Environmental & Chemical Engineering, is part of an approximately $20 million DOE Energy Frontier Research Center, for which she studies carbon sequestration. Daniel Giammar, PhD, the Walter E. Browne Professor of Environmental Engineering, is principal investigator on a $1 million DOE grant to research sequestration techniques. CCCU provided matching funds to DOE to secure the grant. In addition, Brent Williams, PhD, the Raymond R. Tucker Distinguished I-CARES Career Development Assistant Professor, and Pratim Biswas, PhD, the Lucy and Stanley Lopata Professor and chair of the Department of Energy, Environmental & Chemical Engineering, received $331,438 from the National Science Foundation to study emissions and aerosol formation from coal combustion and co-firing of coal and biomass.

Outside of the School of Engineering & Applied Science, Sophia Hayes, PhD, associate professor of chemistry, with principal investigator Mark Conradi, PhD, professor of physics, has developed a new nuclear magnetic resonance (NMR) process for monitoring carbon dioxide during capture and sequestration. Because of Hayes' success with this technique, she recently was awarded $590,294 from DOE with a University of Georgia colleague, again with matching CCCU funds, to continue work in this area. Hayes also was invited to join a $15 million DOE Energy Frontier Research Center studying post-combustion carbon capture.

"An important part of the CCCU is attracting faculty and students to address the challenges of clean coal utilization," Axelbaum says. "Our people are making Washington University an exciting place to do coal research. And in turn, we are developing science and technology to enable low-cost, low-emissions technologies that can supply reliable energy worldwide."