Laboratory tests at elevated pressures of a silane igniter system for in-situ coal gasification

Technical Report · Mon Nov 15 04:00:00 EST 1982

OSTI ID:6787981

Thorsness, C B; Skinner, D F; Fields, D B

A silane/propane igniter and burner system was used for the first time in underground coal gasification experiments in the Tono Basin of Washington in the winter of 1981-1982. With this system, a small-diameter tube (1/2-in.) is inserted in the hole to the point where ignition is desired; the tube is then purged with nitrogen to drive out the air, and a charge of the pyrophoric gas silane (SiH/sub 4/) is forced through it; when the silane reaches the end of the tube, it bursts into flame upon exposure to the air; finally, a fuel gas such as propane is sent through the tube behind the silane to sustain the burn for as long as desired. The system was designed both for igniting coal and for burning through steel pipe from the inside to provide a new outlet from the pipe. The system performed both functions successfully during the Tono Basin field experiments, although difficulties were noted which prompted us to undertake a careful laboratory study of the system's operation after the field experiments were over. The laboratory study had two main goals: to determine the optimum operating procedure for the igniter system, and to test the system under elevated pressures such as may be encountered in underground coal gasification. We found that the essential steps in the operating procedure are to turn off the flow briefly after the silane reaches the end of the tube, then slowly begin the flow of fuel behind the silane. Both propane and methane were tested as fuels; propane was judged to be preferable for pressures up to about 70 psia (5 atm), and methane for higher pressures. The upper pressure limit for silane ignition was found to be about 230 psia (16 atm). 3 figures, 12 tables.

• Research Organization: Lawrence Livermore National Lab., CA (USA)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 6787981
• Report Number(s): UCRL-53361; ON: DE83007217
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404* -- Coal
Lignite
& Peat-- Gasification
AIR
ALKANES
BENCH-SCALE EXPERIMENTS
BURNERS
CHEMICAL REACTIONS
COAL GASIFICATION
COMBUSTION
DATA
ELEMENTS
ENHANCED RECOVERY
EXPERIMENTAL DATA
FLUIDS
GASES
GASIFICATION
HYDRIDES
HYDROCARBONS
HYDROGEN COMPOUNDS
IGNITION
IN-SITU COMBUSTION
IN-SITU GASIFICATION
IN-SITU PROCESSING
INFORMATION
MEDIUM PRESSURE
METHANE
NITROGEN
NONMETALS
NUMERICAL DATA
ORGANIC COMPOUNDS
OXIDATION
PROCESSING
PROPANE
RECOVERY
SILANES
SILICON COMPOUNDS
THERMAL RECOVERY
THERMOCHEMICAL PROCESSES