Phoenix-NASA Low Temperature Multi-Pollutant (NOx, SOx Mercury) Control System for Fossil Fuel Combustion

摘要

Phoenix Systems International, Inc. (PSII) and National Aeronautics and Space Administration (NASA) worked together to completed the development of the Low Temperature Multi-Pollutant Control System (MPCS). PSII and NASA jointly developed a gas-phase oxidizer system that effectively (-100%) converts nitric oxide (NO), the primary NOx component from fossil-fuel combustion, to NO2. It was found that the NO oxidizer system also oxidizes elemental Mercury in the gas phase, which ultimately led to a system that captures 95 percent of the total Mercury emissions. Capture of SOx (primarily SO2) was necessary in order to efficiently oxidize NO to NO2. The capture efficiency for SOx is 99 percent and the capture efficiency for NOx is 98 percent. All of these tests were performed on a 3 MWe slip-stream from a coal-fired power plant located in South Carolina by an EPA Certified independent laboratory. The design of the Phoenix MPCS is highly efficient, but the process is simple and the system is easy to construct and maintain, which lowers the capital and operating costs. The consumables are commonly available, no expensive catalysts are needed, common mechanical system components are used, and operational components are well known. By-products of the process are components of commercial fertilizers, which may be sold for additional reduction of the operating costs. The projected average capital costs for the integrated SOx/NOx system is $275 per kW as compared with $365 per kW for a combined SCR/FGD system. The average Phoenix MPCS operating cost based on pilot unit data for SOx/NOx is $1,175 per ton as compared with $1,310 per ton for a combined SCR/FGD system. The values for the Phoenix MPCS do not include credit for fertilizer or other by-product sales and the Mercury removal capability.