New Albany shale flash pyrolysis under hot-recycled-solid conditions: Chemistry and kinetics, II

Conference · Thu Nov 01 04:00:00 EST 1990

OSTI ID:6306677

Coburn, T T; Morris, C J

The authors are continuing a study of recycle retorting of eastern and western oil shales using burnt shale as the solid heat carrier. Stripping of adsorbed oil from solid surfaces rather than the primary pyrolysis of kerogen apparently controls the release rate of the last 10--20% of hydrocarbons. Thus, the desorption rate defines the time necessary for oil recovery from a retort and sets the minimum hold-time in the pyrolyzer. A fluidized-bed oil shale retort resembles a fluidized-bed cat cracker in this respect. Recycled burnt shale cokes oil and reduces yield. The kerogen H/C ratio sets an upper limit on yield improvements unless external hydrogen donors are introduced. Steam can react with iron compounds to add to the H-donor pool. Increased oil yield when New Albany Shale pyrolyzes under hot-recycled-solid, steam-fluidization conditions has been confirmed and compared with steam retorting of acid-leached Colorado oil shale. In addition, with retorted, but unburnt, Devonian shale present at a recycle ratio of 3, the authors obtain 50% more oil-plus-gas than with burnt shale present. Procedures to make burnt shale more like unburnt shale can realize some increase in oil yield at high recycle ratios. Reduction with H{sub 2} and carbon deposition are possibilities that the authors have tested in the laboratory and can test in the pilot retort. Also, eastern spent shale burned at a high temperature (775 C, for example) cokes less oil than does spent shale burned at a low temperature (475 C). Changes in surface area with burn temperature contribute to this effect. 15 refs., 8 figs., 4 tabs.

• Research Organization: Lawrence Livermore National Lab., CA (USA)
• Sponsoring Organization: DOE/FE
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 6306677
• Report Number(s): UCRL-JC-105169; CONF-901181--3; ON: DE91006708
• Country of Publication: United States
• Language: English

Related Subjects

04 OIL SHALES AND TAR SANDS
040402* -- Oil Shales & Tar Sands-- Surface Methods
044000 -- Oil Shales & Tar Sands-- Combustion-- (1990-)
BITUMINOUS MATERIALS
BLACK SHALES
CARBON
CARBONACEOUS MATERIALS
CARBONIZATION
CHATTANOOGA FORMATION
CHEMICAL ANALYSIS
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
CHEMICAL REACTORS
COKING
COLORADO
COMBUSTION
DECOMPOSITION
DEPOSITION
DESIGN
DESORPTION
DEVOLATILIZATION
DEVONIAN PERIOD
DISTILLATION EQUIPMENT
ELEMENTS
ENERGY SOURCES
ENERGY TRANSFER
EQUIPMENT
FEDERAL REGION IV
FEDERAL REGION VIII
FISCHER ASSAY
FLASH HEATING
FLUIDIZED BEDS
FOSSIL FUELS
FUELS
GEOLOGIC AGES
GEOLOGIC FORMATIONS
GREEN RIVER FORMATION
HEAT TRANSFER
HEATING
HYDROGEN TRANSFER
KENTUCKY
KEROGEN
KINETICS
MATERIALS
NONMETALS
NORTH AMERICA
OIL SHALES
OIL YIELDS
ORGANIC MATTER
OXIDATION
PALEOZOIC ERA
POROSITY
PYROLYSIS
REACTION KINETICS
RECYCLING
RESEARCH PROGRAMS
RETORTING
RETORTS
SPENT SHALES
STEAM
SURFACE AREA
SURFACE PROPERTIES
TEMPERATURE DEPENDENCE
THERMOCHEMICAL PROCESSES
TIME DEPENDENCE
USA
YIELDS