Ammonia evolution during oil shale pyrolysis

Journal Article · · Energy Fuel; (United States)

DOI:https://doi.org/10.1021/ef00007a015· OSTI ID:5140331

Oh, M S; Taylor, R W; Coburn, T T; Crawford, R W

Ammonia ((NH/sub 3/) evolution during pyrolysis of three Green River Formation shales and one Eastern (Devonian) shale was studied. The yields of NH/sub 3/ from Fischer assay type experiments were measured with an NH/sub 3/-sensing electrode, and the time-dependent rate of NH/sub 3/ evolution was measured with a triple-quadrupole mass spectrometer. We varied the peak temperature (PT) of the pyrolysis from 350 to 750 2/C and the heating rate from 1 to 50/sup 0/C/min. The NH/sub 3/ yields increased rapidly above the oil-generating temperatures to a maximum at PT approx. 700/sup 0/C and then decreased at PT > 700/sup 0/C because of the decomposition of NH/sub 3/. The NH/sub 3/ yield showed no dependence on the heating rate at PT < 550/sup 0/C and decreased with increasing heating rate at higher peak temperatures. For Green River Formation shales, the yield of NH/sub 3/ at PT < 500/sup 0/C reflected the organic nitrogen content. The extent of NH/sub 3/ decomposition varied with gas environments, solid surface, and the conditions of the retort can. Because steam works as an inhibitor for the decomposition reaction, we used steam as a retorting gas to obtain the total yield of NH/sub 3/. We developed a kinetic model for NH/sub 3/ evolution; it takes into account NH/sub 3/ generation from organic and inorganic nitrogen sources and NH/sub 3/ decomposition.

• Research Organization: Lawrence Livermore National Lab., CA (USA)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5140331
• Journal Information: Energy Fuel; (United States), Journal Name: Energy Fuel; (United States) Vol. 2:1; ISSN ENFUE
• Country of Publication: United States
• Language: English

Related Subjects

04 OIL SHALES AND TAR SANDS
040900* -- Oil Shales &amp; Tar Sands-- Waste management
500200 -- Environment
Atmospheric-- Chemicals Monitoring &amp; Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AMMONIA
BITUMINOUS MATERIALS
CARBONACEOUS MATERIALS
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
DATA
DECOMPOSITION
ENERGY SOURCES
EXPERIMENTAL DATA
FOSSIL FUELS
FUELS
GEOLOGIC FORMATIONS
GREEN RIVER FORMATION
HYDRIDES
HYDROGEN COMPOUNDS
INFORMATION
KINETICS
MASS SPECTROSCOPY
MATERIALS
MATHEMATICAL MODELS
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
NUMERICAL DATA
OIL SHALES
PRODUCTION
PYROLYSIS
REACTION KINETICS
SPECTROSCOPY
TEMPERATURE DEPENDENCE
THERMOCHEMICAL PROCESSES
TIME DEPENDENCE
YIELDS