Investigation of soot formation characteristics of alternative liquid fuels in spray flames. Final technical report. [Pure n-hexadecane; 90% n-hexadecane/10% toluene; 70% n-hexadecane/30% toluene; 90% n-hexadecane/10% 1-methyl naphthalene]

Technical Report · Mon Aug 01 04:00:00 EDT 1983

OSTI ID:5457968

Sangiovanni, J J

Through a series of well-controlled droplet combustion experiments, the soot formation characteristics of alternative liquid fuels in spray flames were investigated. To simulate a wide range of practical conditions for spray flames, the test matrix included four (4) model fuels, three (3) coal-derived synthetic liquid fuels, three (3) ambient conditions (temperature and oxygen concentration), three (3) interdroplet spacings, and three (3) droplet residence times. A specially-developed electrostatic probe was used to separate and extract samples of liquid droplets and gas phase soot from the spray flames. The physical and chemical properties of the various samples of soot particles and partially burned fuels were then studied to provide an improved understanding of the dominant physical and chemical processes which govern soot formation in spray flames. Analyses of samples of partially burned liquid fuels by gas chromatography indicate that liquid phase chemical processes do not occur in light fuel oils, such as No. 2 fuel oil, during droplet combustion. No conclusions, however, could be made about similar changes in the chemical composition of heavy distillate fuel oils during combustion. Studies of the morphology of soot samples by transmission electron microscopy show clearly that the growth of soot particles in spray flames is extremely rapid. However, when the individual soot spheroids reach a mean diameter of about 250 A to 350 A they cease growing. Possible explanations for these soot particle growth trends are proposed. Elemental analyses indicate that the carbon-to-hydrogen atomic ratio of soot varies with residence time in the flame from about 12:1 to 8:1. Identification of the hydrocarbon functional group composition of the soot by infrared absorption spectroscopy shows a corresponding shift in the hydrogen containing molecules from aliphatic to aromatic structures as the soot ages. 21 references, 16 figures, 3 tables.

• Research Organization: United Technologies Research Center, East Hartford, CT (USA)
• DOE Contract Number: AC22-80PC30195
• OSTI ID: 5457968
• Report Number(s): DOE/PC/30195-1; ON: DE84004558
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
025000 -- Petroleum-- Combustion
03 NATURAL GAS
034000* -- Natural Gas-- Combustion
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800 -- Combustion
Pyrolysis
& High-Temperature Chemistry
ABSORPTION SPECTROSCOPY
ALKANES
AROMATICS
CHEMICAL COMPOSITION
CHROMATOGRAPHY
COAL LIQUEFACTION
COAL LIQUIDS
COMBUSTION PROPERTIES
CONDENSED AROMATICS
DATA
DROPLETS
ELECTRON MICROSCOPY
EXPERIMENTAL DATA
FLAMES
FLUIDS
FUEL OILS
FUELS
GAS CHROMATOGRAPHY
HEATING OILS
HEXADECANE
HYDROCARBONS
INFORMATION
LIQUEFACTION
LIQUID FUELS
LIQUIDS
MICROSCOPY
MORPHOLOGY
NUMERICAL DATA
OILS
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
PARTICLE SIZE
PARTICLES
PETROLEUM PRODUCTS
SEPARATION PROCESSES
SIZE
SOOT
SPECTROSCOPY
SPRAYS
SRC-II PROCESS
SYNTHESIS
TEMPERATURE MEASUREMENT
THERMOCHEMICAL PROCESSES
TOLUENE
TRANSMISSION ELECTRON MICROSCOPY