RTI advances syngas cleanup technology at Tampa’s Polk plant

A demonstration-scale application of RTI International’s warm synthesis gas (syngas) cleanup process technology has achieved a key operational milestone at Tampa Electric‘s coal gasification plant in Polk County, Fla.

The unit has accumulated more than 1,000 hours of operation on a coal- and petroleum-coke-based syngas feed and achieved 99.9% sulfur removal at temperatures as high as 600 degrees Celsius, said the U.S. Department of Energy in a Feb. 19 statement. When integrated with a downstream system for carbon capture, total sulfur in cleaned syngas was reduced to less than 1 part per million (ppm), resulting in more than 99.99% total sulfur removal. The new innovation is a lower-cost way to clean the syngas from coal to levels below EPA requirements and enable the syngas to be used cost-effectively in the production of chemicals and fuels.

RTI’s syngas cleanup technology removes contaminants at warm process temperatures, reducing or eliminating the need for substantial syngas cooling and expensive heat-recovery systems, DOE noted. As a result, the process increases thermal efficiency and reduces the capital and operating costs of new gasification-based systems compared to conventional syngas cleanup technologies.

Unit 1 of the Polk Power Station was built near Tampa in the mid-1990s and was presented the 1997 Power Plant Award by Power magazine. It was selected in 1989 as a demonstration project as part of the DOE Office of Fossil Energy’s Clean Coal Technology Program, managed by the National Energy Technology Laboratory (NETL).

The unit currently gasifies a blend of coal and petroleum coke with oxygen to produce syngas. After going through a cleaning process, the syngas is burned in a combustion turbine to produce electricity, while excess heat from the combustion turbine is recovered to generate more electricity in a steam turbine. An opportunity to improve current integrated gasification combined-cycle (IGCC) technologies exists by developing syngas cleaning technologies that integrate more efficient process conditions. The warm syngas cleaning technology installed by RTI at Polk offers advantageous heat integration and is seen as a key for increasing overall system efficiencies and reducing costs with even better environmental performance.

In 2010, RTI was selected by DOE to receive $168.8 million in American Recovery and Reinvestment Act funding to scale-up its novel syngas cleaning technology, coupled with more than 90% carbon capture, at the Polk plant. RTI is now seeking a suitable partner(s) to help drive global commercial deployment of the technology.

In addition to DOE-funded efforts at Polk, there are three other DOE-supported projects working to integrate RTI’s syngas cleanup technology with other advanced technologies: Aerojet Rocketdyne’s Compact Gasifier, an RTI advanced water-gas-shift process, and an RTI advanced Fischer-Tropsch reactor liquid fuel process.

The 260-MW Polk IGCC facility began commercial operation in the fall of 1996. Since then other units fired with regular natural gas have been added at this inland facility. The coal and petcoke for the IGCC is trucked from the Big Bend coal plant of Tampa Electric, which is on Tampa Bay and has access to both barge and rail deliveries of solid fuels. There were plans for a second IGCC at Polk that were dropped last decade when the state took an anti-coal stance due to climate-change concerns.

About Barry Cassell 20414 Articles
Barry Cassell is Chief Analyst for GenerationHub covering coal and emission controls issues, projects and policy. He has covered the coal and power generation industry for more than 24 years, beginning in November 2011 at GenerationHub and prior to that as editor of SNL Energy’s Coal Report. He was formerly with Coal Outlook for 15 years as the publication’s editor and contributing writer, and prior to that he was editor of Coal & Synfuels Technology and associate editor of The Energy Report. He has a bachelor’s degree from Central Michigan University.