Sorbent and ammonia injection at economizer temperatures upstream of a high-temperature baghouse

Journal Article · Wed Aug 01 04:00:00 EDT 1990 · Environmental Progress; (USA)

DOI:https://doi.org/10.1002/ep.670090314· OSTI ID:5707228

Chu, P; Downs, B; Holmes, B ^[1]

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1. Babcock and Wilcox Co., Alliance, OH (USA)

The current technology of choice - world-wide - for post-combustion NO{sub x} control is selective catalytic reduction (SCR) with ammonia. The application of SCR to coal-fired units has proven to be somewhat more difficult than its application to natural gas and oil-fired units due to SO{sub 2} poisoning of the catalyst, catalytic oxidation of SO{sub 2} to SO{sub 3}, and erosion and fouling of the catalyst by fly ash. These problems could be potentially diminished if SO{sub 2} and particulate removal systems were placed upstream of the SCR reactor. However, this is not easily accomplished since SCR systems operate best in the temperature range of 600{degree}F-800{degree}F (315{degree}C-425{degree}C). Several SCR installations in Europe employ conventional flue gas desulfurization (FGD) and particulate control upstream of flue gas reheat and SCR. However, the flue gas reheat typically imposes a 1%-2% energy penalty. Several recent technical developments now offer a technology whereby these limitations of SCR for coal applications can be alleviated. These technical developments are in the areas of high temperature filtration, improved SCR catalysts, and advances in sorbent injection. These advances have been incorporated into a patented process known as the SO{sub x}-NO{sub x}-Rox Box (SNRB) process. Briefly, this process consists of a hot baghouse employing woven ceramic fabric bags, a zeolite SCR catalyst incorporated into the baghouse, and the injection of either calcium- or sodium-based sorbent upstream of the baghouse. This paper deals with the status and development of the SNRB process, including some results from recently completed pilot-plant tests performed under a contract with the Ohio Coal Development Office (OCDO).

• OSTI ID: 5707228
• Journal Information: Environmental Progress; (USA), Journal Name: Environmental Progress; (USA) Vol. 9:3; ISSN ENVPD; ISSN 0278-4491
• Country of Publication: United States
• Language: English

Related Subjects

20 FOSSIL-FUELED POWER PLANTS
200200* -- Fossil-Fueled Power Plants-- Waste Management
AMMONIA
APPROPRIATE TECHNOLOGY
BAGHOUSES
CARBONACEOUS MATERIALS
CATALYTIC COMBUSTORS
CHALCOGENIDES
CHEMICAL REACTIONS
COAL
COMBUSTORS
DESULFURIZATION
ENERGY SOURCES
EQUIPMENT
FLUE GAS
FOSSIL FUELS
FOSSIL-FUEL POWER PLANTS
FUELS
FUNCTIONAL MODELS
GASEOUS WASTES
HYDRIDES
HYDROGEN COMPOUNDS
MATERIALS
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
NITROGEN OXIDES
OXIDES
OXYGEN COMPOUNDS
PILOT PLANTS
POLLUTION CONTROL EQUIPMENT
POWER PLANTS
REDUCTION
SULFUR COMPOUNDS
SULFUR DIOXIDE
SULFUR OXIDES
THERMAL POWER PLANTS
WASTES