Compression ignition of coal slurry fuels

Technical Report · Sun Dec 01 04:00:00 EST 1985

OSTI ID:5543517

Brehob, D D; Sawyer, R F

Slow- and medium-speed compression ignition engines have the potential for conversion to coal fueling. Previous engine studies on coal slurries have investigated wear, thermal efficiency, and injection performance without evaluating the ignition characteristics. The ignition delay times and conditions for ignition of 45 mass % coal in methanol, diesel No. 2, and water are compared to diesel No. 2 and methanol in the present study. The slurries are evaluated using a 900 rpm, direct injection, square piston engine simulator operating for one combustion cycle per experiment. Both 16:1 and 22:1 compression ratios are used with 2 atm abs. inlet air at temperatures from ambient to 250/sup 0/C. The square geometry accommodates windows on two opposite walls of the combustion chamber for complete optical access. All of the test fuels except coal/water slurry ignited at the operating conditions attainable in the engine simulator. The temperature at time of injection required to obtain ignition is approximately 680 K for diesel No. 2 and coal/diesel slurry, 725 K for coal/methanol slurry, and 825 K for neat methanol. Activation temperatures, T/sub a/, in the Arrhenius-type expression are: 5559 K for diesel No. 2, 7685 K for methanol, 3541 K for coal/diesel, and 5330 K for coal/methanol by the pressure delay method and 4357 K for diesel No. 2, 3926 K for coal/diesel, and 5510 K for coal/methanol by the luminosity delay method. The results establish the compression ignitability of the coal/methanol and coal/diesel slurry fuels at conditions appropriate to medium-speed diesel engines.

• Research Organization: Lawrence Berkeley Lab., CA (USA)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 5543517
• Report Number(s): LBL-20878; CONF-860804-10; ON: DE86007496
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330102* -- Internal Combustion Engines-- Diesel
330800 -- Emission Control-- Alternative Fuels
ALCOHOLS
DATA
DIESEL ENGINES
DIESEL FUELS
DISPERSIONS
ENGINES
EXPERIMENTAL DATA
FUEL OILS
FUEL SLURRIES
FUEL SUBSTITUTION
FUELS
HEAT ENGINES
HYDROXY COMPOUNDS
IGNITION
INFORMATION
INTERNAL COMBUSTION ENGINES
LIQUID FUELS
METHANOL
MIXTURES
NUMERICAL DATA
OILS
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
PETROLEUM PRODUCTS
SLURRIES
SUSPENSIONS