DOE, RTI to Design and Build Coal Syngas Cleanup System for IGCC Power Plants to Reduce Cost of Removing Contaminants, Capturing CO2; Potential for Synthetic Chemicals and Fuels
|The RTI/Eastman syngas cleanup technology platform. Click to enlarge.|
Extending a relationship of more than a decade, the US Department of Energy (DOE) and Research Triangle Institute (RTI) International will collaborate on a project designed to advance the development 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 system also holds the potential to reduce the cost of producing chemicals, transportation fuels, and substitute natural gas from gasified coal.
DOE and RTI will design, build, and test a warm gas cleanup system—based on RTI’s high-temperature syngas cleanup technology—to remove multiple contaminants from coal-derived syngas. The 50-MWe system will include technologies to remove trace elements such as mercury and arsenic, capture the greenhouse gas carbon dioxide (CO2), and extract more than 99.9% of the sulfur from the syngas.
A novel process to convert the extracted sulfur to a pure elemental sulfur product will also be tested.
In integrated gasification combined cycle (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 be tested at Tampa Electric Company’s 250-MW IGCC power plant, using up to 20% of the syngas produced by the coal gasifier. 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.
Because of the benefits of IGCC power plants, high-temperature syngas cleaning technologies have been the subject of intense investigation for more than two decades. This project will be the world’s first large-scale testing of such a technology.
The Office of Fossil Energy’s National Energy Technology Laboratory will manage the 5-year project. With successful completion of the project, the RTI warm gas cleanup system will be ready for full-scale commercial demonstration and deployment.
Background. In 2008, RTI International and Eastman Chemical Company agreed to develop and commercialize jointly developed syngas cleanup technology. The novel high-temperature technology package provided a modular approach to the removal of various contaminants contained in syngas derived from coal and petroleum coke, leading to significantly higher thermal efficiency and reduced capital and operating costs.
A DOE-funded system study predicts a 2-3% 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.
Components of the technology package included a high-temperature desulfurization process that uses transport reactors; an attrition-resistant regenerable zinc oxide based sorbent; a fixed-bed catalytic process for converting sulfur dioxide produced during the sorbent regeneration into elemental sulfur; and fixed-bed reactor processes for removal of other syngas contaminants.
The technology was developed by RTI at laboratory and bench-scale over more than a decade with funding from the US Department of Energy’s Office of Fossil Energy/National Energy Technology Laboratory.
One of the key processes targeted for on-going work at that time was development of a high-temperature process for removal of CO2 from syngas to produce a sequestration-ready CO2 stream, with a goal of seamless integration of CO2 removal in the high-temperature syngas cleanup system.
Status of RTI/Eastman Warm Gas Clean-up Technology and Commercialization Plan (Gasification Technologies Conference, 2008)