To prevent air pollution, Stanton Energy Center (SEC) uses low-sulfur, low-ash coal and operates state-of-the-art pollution control equipment to remove pollutants. State-certified instruments continuously monitor emissions to verify actual removal. The Florida Department of Environmental Protection reviews air-monitoring data from SEC. Air sampling has shown that Stanton’s emissions are among the lowest of any coal-fired plant in the nation.
Coal burning in the boiler creates gaseous and particulate (solid) byproducts called flue gas. Particulates, Nitric Oxides (NOx), and Sulfur Oxides (S02) are present in the flue gas. Emissions of these byproducts are monitored closely by the Stanton Energy Center to ensure adherence to established governmental environmental standards.
Unit 2: NOx is controlled by efficient low-NOx burners and Selective Catalytic Reduction equipment (Unit 1 also uses low-NOx burners). Burners are designed to minimize NOx by burning at low temperatures with a minimum amount of turbulence and utilizing as much time as possible to complete the burn. The Selective Catalytic Reduction process converts NOx to harmless Nitrogen (N2) and water (H2O) by spraying Ammonia (NH3) into the flue gas and allowing the flue gas to pass through a catalyst material to enhance the chemical reaction.
Units 1 and 2: Particulates are controlled in an electrostatic precipitator. This equipment electrically charges the solid particles (fly ash) so that they will be attracted to oppositely charged plates. Large hammers periodically hit the plates causing the fly ash to fall to the bottom of the precipitator so that a vacuum system can transport it for storage in a silo.
S02 is controlled by a wet limestone scrubber. In the scrubber, a limestone and water slurry (scrubber slurry) is sprayed over the flue gas. The S02 reacts chemically with the limestone and water slurry in the flue gas and becomes a suspended solid in the scrubber slurry. As this process continues, the scrubber slurry increases in solid content and becomes more acidic. To maintain this chemistry in a balance, spent scrubber slurry is removed as new fresh slurry is added. The spent scrubber slurry is transported away for the disposal process.
The fly ash removed in the electrostatic precipitator and the spent scrubber sludge from the flue gas scrubber are mixed with lime. The addition of lime to this mixture causes the material to harden much like concrete. This material is transported to the Combustion Waste Storage Area near the western boundary of the site. After placement, this material is compacted, contoured, covered with topsoil and seeded.
Material deposited in this landfill is environmentally stable. Since it is essentially impervious, it will not contaminate the groundwater. Monitoring wells are placed throughout the site to ensure that the groundwater has not been contaminated.
The Curtis H. Stanton Energy Center is a strategically phased powerhouse comprising a portfolio of clean, modern, fuel-diverse, environmentally sound power-generation equipment. Newsweek magazine has described it as non-polluting. Others just call it a good neighbor. With good reason: When it comes to protecting the environment, OUC goes above and beyond — always using the best technology available at the time of construction.
The Curtis H. Stanton Energy Center’s Unit 1 began operating in 1987 to meet the growing electricity needs of Central Florida. Unit 2 began operating in 1996. The coal-fired units have enabled OUC to reduce its dependency on oil and gas and give it the fuel flexibility to provide customers with the best reliability and some of the lowest electric rates in Florida.
State-of-the-art pollution control equipment used by the Stanton Energy Center enables the plant to operate as a zero-water discharge facility.
The Stanton Energy Center gets most of the water it needs from Orange County’s Eastern Wastewater Treatment Facility. About 10 million gallons of water is pumped to the site each day and eventually evaporated through the cooling towers.
While re-using this water that otherwise would end up in the Econlockhatchee River, OUC reduces the demand on our precious groundwater supply. All rain runoff on the site is diverted to holding ponds for re-use.
Groundwater monitoring wells around each pond verify that none of this water leaks into the surficial Aquifer. This water is used in the pollution control process and every day approximately 925,000 gallons eventually evaporate from the tall stacks.
Both Stanton Units I and II were ahead of their time in terms of advanced environmental technology. And both continue to be better than they have to be when it comes to meeting air quality standards. According to federal monitoring agencies, these units are among the most environmentally sound coal-burning operations in the nation. And, we plan to keep them that way by continuing to modernize them with advanced technologies that optimize efficiency, environmental performance and operating flexibility.
A combined cycle power-generation facility, Stanton A helps OUC maintain stable power prices by further diversifying our fuel mix and maintaining flexibility through the use of purchased-power agreements.