Method for explosive expansion toward horizontal free faces for forming an in situ oil shale retort

Patent · Tue Mar 11 04:00:00 EST 1980

OSTI ID:5720432

Ricketts, T E

Formation is excavated from within a retort site in formation containing oil shale for forming a plurality of vertically spaced apart voids extending horizontally across different levels of the retort site, leaving a separate zone of unfragmented formation between each pair of adjacent voids. Explosive is placed in each zone, and such explosive is detonated in a single round for forming an in situ retort containing a fragmented permeable mass of formation particles containing oil shale. The same amount of formation is explosively expanded upwardly and downwardly toward each void. A horizontal void excavated at a production level has a smaller horizontal cross-sectional area than a void excavated at a lower level of the retort site immediately above the production level void. Explosive in a first group of vertical blast holes is detonated for explosively expanding formation downwardly toward the lower void, and explosive in a second group of vertical blast holes is detonated in the same round for explosively expanding formation upwardly toward the lower void and downwardly toward the production level void for forming a generally t-shaped bottom of the fragmented mass.

• Assignee: Occidental Oil Shale Inc
• Patent Number(s): US 4192554
• OSTI ID: 5720432
• 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
CHEMICAL REACTIONS
COMMINUTION
DECOMPOSITION
ENERGY SOURCES
EXCAVATION
EXPLOSIVE FRACTURING
FOSSIL FUELS
FRACTURING
FUELS
IN-SITU PROCESSING
IN-SITU RETORTING
MATERIALS
MINERAL OILS
OIL SHALES
OILS
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
PROCESSING
RETORTING
SHALE OIL