The U.S. Department of Energy (DOE) is preparing to conduct what it says is the world’s first large-scale project to design, build, and test a warm gas cleanup system to remove multiple contaminants from coal-derived syngas. The federal agency has teamed with Research Triangle Institute (RTI) International, a scientific research firm, to demonstrate the 50-MW system at Tampa Electric Co.’s 250-MW integrated gasification combined-cycle (IGCC) power plant.
The system will include technologies to remove trace elements such as mercury and arsenic, capture carbon dioxide (CO2), and extract more than 99.9% of the sulfur from the syngas, the DOE said on Monday. A novel process to convert the extracted sulfur to a pure elemental sulfur product will also be tested.
“This project supports DOE’s vision of coal power plants with near-zero emissions by reducing the cost and improving the efficiency of capturing CO2 and removing contaminants from syngas derived from coal,” the agency said in a press release. “The system also holds the potential to reduce the cost of producing chemicals, transportation fuels, and substitute natural gas from our vast domestic coal resources, thereby enhancing America’s energy security and economic prosperity.”
In IGCC power plants, coal-derived syngas—a mixture of carbon monoxide and hydrogen—is used to fuel a combustion turbine for the production of electricity. Reacting the carbon monoxide in syngas with steam to produce hydrogen and CO2 allows for the capture and sequestration of the CO2, preventing it from being released into the atmosphere.
RTI’s syngas cleanup technologies will use up to 20% of the syngas produced at Tampa Electric Co.’s IGCC power plant. Data on thermal efficiency, emissions, and cost benefits will be gathered during more than 5,000 hours of testing the warm syngas cleaning system. “This information will help refine the integration strategy in an IGCC plant and mitigate technical risks associated with commercial deployment of this technology,” the DOE said.
Because of the benefits of IGCC power plants, high-temperature syngas cleaning technologies have been intensely studied for over two decades, but not at the scale the DOE has proposed, it said. A system study funded by the agency predicts a 2 to 3 percentage point increase in overall IGCC thermal efficiency and a 6% reduction in the cost of electricity by using the RTI contaminant removal process for an IGCC plant. Coupling this technology with a high-temperature CO2 capture technology will minimize the impact of carbon capture on retail electricity costs.
The DOE’s Office of Fossil Energy’s National Energy Technology Laboratory will manage the five-year project. With successful completion of the project, the agency expects that the RTI warm gas cleanup system will be ready for full-scale commercial demonstration and deployment.