NO/sub x/-char reactions: Kinetics and transport aspects: Quarterly technical progress report, 1 January 1988-31 March 1988

Technical Report · Fri Jan 01 04:00:00 EST 1988

OSTI ID:6910302

Calo, J M; Suuberg, E M; Makhija, S; Teng, H; Lilly, W D

Reduction of NO/sub x/ emissions from coal combustors remains among the most important unresolved environmental control problems associated with the utilization of coal. In stationary combustion devices, NO/sub x/ is produced from both nitrogen in the combustion air and from the fixed fuel nitrogen (i.e., originating from the chemical matrix of the fuel). Combustion of coal generally results in the conversion of about 15/endash/40/percent/ of the fuel nitrogen to NO. It is generally agreed that most of the primary NO/sub x/ formed in combustors is as NO rather than NO/sub 2/. The formation mechanisms of NO/sub x/ have received significant attention. NO/sub x/ formation from fuel nitrogen, for example, has been found to be dependent on a complex series of homogeneous and heterogeneous mechanistic steps. However, an understanding of NO formation is only part of the story; the development of NO control strategies must also be guided by a knowledge of its destruction mechanisms. An appreciable portion of the NO initially formed within the particle (i.e., from fuel nitrogen) can be destroyed by NO-char reactions before it can ever escape. The destruction of NO external to the particle includes both homogeneous gas phase processes and heterogeneous processes that require transport of NO to the surface, including gas-solid reactions between the char and NO, and/or catalytic reactions between absorbed species, such as NO and CO, on the char surface. Different mechanisms are believed to predominate in different situations. This difficulty in drawing firm conclusions regarding the role of heterogeneous NO/sub x/ reduction mechanisms is partly due to the fact that some aspects remain very poorly understood. The objective of this project is to develop an improved understanding of the chemical kinetics and mass transport characteristics of the heterogeneous interactions of NO/sub x/ with char. 39 refs., 6 figs., 2 tabs.

• Research Organization: Brown Univ., Providence, RI (USA). Div. of Engineering
• DOE Contract Number: FG22-87PC79929
• OSTI ID: 6910302
• Report Number(s): DOE/PC/79929-1; ON: DE88013722
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
014000 -- Coal
Lignite
& Peat-- Combustion
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ABSORPTION
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CHALCOGENIDES
CHARS
CHEMICAL ANALYSIS
CHEMICAL EFFLUENTS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CHEMICAL REACTORS
DECOMPOSITION
DIFFUSION
DOCUMENT TYPES
ELEMENTS
GRAVIMETRIC ANALYSIS
KINETICS
NITRATES
NITROGEN
NITROGEN COMPOUNDS
NONMETALS
ORGANIC COMPOUNDS
ORGANIC POLYMERS
OXIDES
OXYGEN COMPOUNDS
PETROCHEMICALS
PETROLEUM PRODUCTS
POLYMERS
PROGRESS REPORT
PYROLYSIS
PYROLYSIS PRODUCTS
QUANTITATIVE CHEMICAL ANALYSIS
REACTION KINETICS
RESINS
SURFACE AREA
SURFACE PROPERTIES
TEMPERATURE DEPENDENCE
THERMAL ANALYSIS
THERMAL GRAVIMETRIC ANALYSIS
THERMOCHEMICAL PROCESSES