Advanced Combustion

Advanced combustion power generation combusts fossil fuels in a high-oxygen (O₂) concentration environment rather than air. This eliminates most, if not all, of the nitrogen (N₂) found in air from the combustion process, resulting in flue gas composed of CO₂, water (H₂O), contaminants from the fuel (including coal ash), and other gases that infiltrated the combustion system. The high concentration of CO₂ (≈70 percent) and absence of nitrogen simplify separation of CO₂ from the flue gas for storage or beneficial use. Thus, oxygen-fired combustion is an alternative approach to post-combustion capture for carbon capture and storage (CCS) for coal-fired systems. However, the appeal of oxygen-fired combustion is tempered by several challenges, namely capital cost, energy consumption, operational challenges of supplying O₂ to the combustion system, air infiltration that dilutes the flue gas with N₂, and excess O₂ that must be removed from the concentrated CO₂ stream. These factors mean oxygen-fired combustion systems are not affordable at their current level

of development. Advanced combustion system performance can be improved by two means:

• Lowering the cost of oxygen supplied to the system
• Increasing the overall system efficiency

The Advanced Combustion Systems Program targets both of these possible improvements through sponsored cost-shared research into three key technologies:

• Oxy-combustion
• Chemical Looping Combustion (CLC)
• Enabling Technologies/Innovative Concepts

NETL is funding projects within each of the above-mentioned approaches. These R&D efforts are being performed both externally by industry, research organizations, and academic institutions, and internally through NETL’s Research & Innovation Center.