Operation of in situ oil shale retort with void at the top

Patent · Tue Jan 06 04:00:00 EST 1981

OSTI ID:6157570

Cha, C Y

An in situ oil shale retort is formed with an upper surface of a fragmented permeable mass in the retort separated from a top boundary of unfragmented formation, creating an inlet plenum void. A primary combustion zone is established in the fragmented mass, and such primary combustion zone is caused to spread laterally by the establishment of a secondary combustion zone. During a first period of time, the temperature in the inlet plenum void is maintained at less than the temperature at which unfragmented formation from above the top boundary will slough into the void. The primary combustion zone is advanced through the retort and liquid and gaseous products of retorting are withdrawn. During a second period of time the temperature in the inlet plenum void is increased to increase the temperature of the top boundary of unfragmented formation to a temperature which will cause unfragmented formation from above the top boundary to slough into the void. Preferably, sufficient formation is sloughed for substantially completely filling such void to provide support for overlying formation after completion of retorting.

• Assignee: Occidental Oil Shale Inc
• Patent Number(s): US 4243100
• OSTI ID: 6157570
• Country of Publication: United States
• Language: English

Related Subjects

04 OIL SHALES AND TAR SANDS
040401* -- Oil Shales & Tar Sands-- In Situ Methods
True & Modified
BITUMINOUS MATERIALS
CARBONACEOUS MATERIALS
CAVITIES
CHEMICAL REACTIONS
COMBUSTION
CONTROL
DECOMPOSITION
ENERGY SOURCES
FOSSIL FUELS
FUELS
IN-SITU PROCESSING
IN-SITU RETORTING
MATERIALS
OIL SHALES
OXIDATION
PARTICLES
PROCESSING
RETORTING
TEMPERATURE CONTROL
THERMOCHEMICAL PROCESSES