Florida Power Development LLC (FPD) is seeking air permit changes for its biomass-fired, 80-MW Brooksville Power Plant, with the Florida Department of Environmental Protection on Aug. 29 issuing a draft version of that permitting.
The Brooksville Power Plant consists of: a woody biomass grate suspension boiler; biomass handling and storage; in-duct sorbent injection system (IDSIS); bottom ash storage and handling facilities; and fuel oil storage tanks. The plant is located in Hernando County at 10311 Cement Plant Road in Brooksville.
The boiler fires woody biomass as the primary fuel with ultra-low-sulfur distillate (ULSD) fuel oil and natural gas used for startup, shutdown and bed stabilization fuels. Ammonia (NH3) injection into a selective catalytic reduction (SCR) reactor is used to reduce emission of NOx and help in the reduction of organic hazardous air pollutants (HAP). An oxidation catalyst may be used to reduce carbon monoxide (CO), volatile organic compounds (VOC) and organic HAP emissions. An IDSIS utilizing milled trona, hydrated lime, limestone, or sodium bicarbonate is used to control SO2, hydrogen chloride (HCl), hydrogen fluoride and other acid gas HAP emissions. An electrostatic precipitator (ESP) cuts emissions of particulate matter. The ESP also helps in the control of metal HAP and also removes injected sorbents.
FPD is requesting to do a 30-day trial to increase the steam production from the biomass boiler from 490,000 lb/hour to 540,000 lb/hour to obtain operating and emissions data. This information will be used in a future application to request a permanent increase in the steam production. In 2012, FPD converted the existing coal-fired boiler with a maximum heat input of 1,850 million British thermal units per hour (MMBtu/hour) to a 900 MMBtu/hour (490,000 lb/hour steam production) woody biomass-fired boiler.
This application also includes a request to permanently use BCS-180 ASHVANTAGE to help reduce ash fusion on the boiler tubes to improve boiler efficiency and ultimately reduce emissions. The department had previously issued a Letter of Authorization to temporarily use this product. This product is a naturally occurring mineral in granular form, mostly consisting of magnesium oxide. The product will be added to the wood fuel at an injection rate of about 1,000 to 1,500 lb/day (41.7 to 62.5 lb/hour) at the location of the combustor. The ASHVANTAGE reacts with the ash generated during the combustion process and lowers the ash fusion temperature. The primary effect of this reaction is that the ash particles do not stick to the boiler tubes and are more likely to be removed by the ESP.