Catching the flue from fossil fuel combustion

A new grant from the Department of Energy’s Office of Fossil Energy solidifies Ohio State's leading role in carbon capture research. A team led by Distinguished Professor of Engineering Winston Ho will receive $3 million to develop and test innovative membranes for carbon dioxide capture from flue gas.

U.S. Secretary of Energy Rick Perry recently announced eight projects receiving nearly $24 million in Department of Energy (DOE) funds for cost-shared research and development for Novel and Enabling Carbon Capture Transformational Technologies. The selected projects will focus on the development of solvent, sorbent, and membrane technologies to address scientific challenges and knowledge gaps associated with reducing the cost of carbon capture.

“By 2040 the world will still rely on fossil fuels for 77 percent of its energy use. Our goal is to produce them in a cleaner way,” said Perry. “These projects will allow America, and the world for that matter, to use both coal and natural gas with near-zero emissions.”

Carbon dioxide (CO₂) is the greenhouse gas most responsible for global warming. Human activities such as deforestation and burning fossil fuels have increased the natural concentration of carbon dioxide in our atmosphere, amplifying the Earth’s natural greenhouse effect.

Flue gas refers to the combustion exhaust gas produced at fossil fuel power plants. And while membranes that can remove carbon dioxide from industrial gases are not new, there are no commercially available membranes to capture CO₂ from flue gas with marketable incentives.  Professor Ho and his team have developed one of the most cost-effective membranes to date. In the lab, their spiral-wound polymer membrane modules demonstrate high carbon dioxide permeance and selectivity for enhanced gas separation.

“Our novel membrane can capture at least 90 percent of the CO₂ in flue gas,” said Ho. “And the purity of the CO₂ is at least 95 percent.” Purity of the captured gas is important, since demand for quality carbon dioxide is growing in the oil, chemical and food industries. Captured carbon dioxide not used by industry is stored, typically in an underground geological formation, to prevent release into the atmosphere.

“We can capture CO₂ at a lower price than ever before, around $40 per metric ton, and an even lower cost of less than $30 can be achieved, if we only capture 70 percent of the CO₂,” he added, which could attract more industry interest in applying carbon capture technology to flue gas exhaust.

The researchers will optimize and scale up the membrane to a prototype size of 21 inches wide—half of commercial width—and about 1,000 feet long via continuous roll-to-roll fabrication. The membranes are then wound into modules to be used for simulated flue gas testing on a bench skid in the lab. After that, actual flue gas from coal combustion will flow through the membrane modules at the National Carbon Capture Center (NCCC), managed and operated by Southern Company in Alabama.

These transformational carbon capture projects are funded by the Office of Fossil Energy’s (FE’s) Carbon Capture Program. In addition to DOE research funding, the federal government also provides tax credits to fossil fuel companies that incorporate carbon capture and storage systems in their operations. 

The scope of these projects aligns with the scientific challenges and knowledge gaps identified in the DOE ministerial-level Mission Innovation report, Accelerating Breakthrough Innovation in Carbon Capture, Utilization, and Storage, which can be found here.

Ho’s research is also supported by funding from the Ohio Coal Development Office.