Nitrogen pollutant formation in a high-pressure entrained-coal gasifier

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1987

OSTI ID:7075620

Nichols, K M

This study was a combined experimental and theoretical effort to determine (1) why increasing the pressure on a combustion chamber decreases the effluent NO concentration, and (2) which of four simple injector designs will yield the lowest NO and TNF (total free N) during coal gasification. The experiments were performed in a laboratory scale entrained-coal gasifier with Utah bituminous coal. Samples were collected with a water quenched probe and analyzed for gaseous nitrogen species concentrations (N/sub 2/, NO, NH/sub 3/, HCN) and char nitrogen content. The theoretical modeling was performed using PCGC-2, a comprehensive gasification and combustion code. The following points were illustrated by the data and predictions: (1) the rate of homogeneous NO decay was found to increase exponentially with pressure increases, and this was the primary cause for decreased NO; (2) the effect of increased residence time was secondary; and (3) increasing pressure did not decrease the peak NO level produced in or near the flame. Of the injectors tested, the one which swirled the primary coal stream yielded the lowest NO, and a premixed injector yielded the lowest TFN. N/sub 2/ and TFN measurements contained a large degree of data scatter, and were of less value than NO and char nitrogen measurements. PCGC-2 predictions overpredicted the temperatures by 400-1000 K for the diffusion injectors.

• Research Organization: Brigham Young Univ., Provo, UT (USA)
• OSTI ID: 7075620
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404 -- Coal
Lignite
& Peat-- Gasification
010800* -- Coal
Lignite
& Peat-- Waste Management
014000 -- Coal
Lignite
& Peat-- Combustion
AMMONIA
BITUMINOUS COAL
BLACK COAL
CARBONACEOUS MATERIALS
CHALCOGENIDES
CHARS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COAL
COAL GASIFICATION
COMBUSTION KINETICS
COMPUTER CODES
CYANIDES
DECOMPOSITION
ELEMENTS
ENERGY SOURCES
FOSSIL FUELS
FUELS
GAS ANALYSIS
GASIFICATION
HYDRIDES
HYDROCYANIC ACID
HYDROGEN COMPOUNDS
INORGANIC ACIDS
KINETICS
MATERIALS
NITRIC OXIDE
NITROGEN
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
NITROGEN OXIDES
NONMETALS
OXIDES
OXYGEN COMPOUNDS
P CODES
PRESSURE DEPENDENCE
PYROLYSIS PRODUCTS
REACTION KINETICS
SYNTHESIS
THERMOCHEMICAL PROCESSES
TIME DEPENDENCE