Method of blasting pillars with vertical blastholes

Patent · Tue Oct 12 04:00:00 EDT 1982

OSTI ID:6662251

Ricketts, T E

A fragmented permeable mass of formation particles is formed in an in situ oil shale retort in a subterranean formation containing oil shale. Formation is excavated to form a horizontally extending void in the subterranean formation and a support pillar of unfragmented formation is left in the void for supporting overlying unfragmented formation. The support pillar is prepared for explosive expansion by forming an array of explosive charges along the centerline of the pillar between its opposed free faces. The amount of explosive on each side of the centerline is about equal. Explosive is then detonated in the support pillar for expanding the pillar about equally toward both opposed free faces. Thereafter, explosive is detonated in unfragmented formation above and/or below the void for explosively expanding the formation toward the void to form the fragmented permeable mass of formation particles.

• Assignee: Occidental Oil Shale Inc.
• Patent Number(s): US 4353598
• OSTI ID: 6662251
• 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
EXPANSION
EXPLOSIVE FRACTURING
FOSSIL FUELS
FRACTURING
FRAGMENTATION
FUELS
IN-SITU PROCESSING
IN-SITU RETORTING
MATERIALS
OIL SHALES
PROCESSING
RETORTING
SUPPORT PILLARS