In situ oil shale retort having horizontal voids with side pillars

Patent · Tue Jun 12 04:00:00 EDT 1984

OSTI ID:6482842

Ricketts, T E; Burton, R S

An in situ oil shale retort is formed in a subterranean formation containing oil shale by excavating one or more horizontally extending voids across a retort site, leaving a zone of unfragmented formation having a horizontal free face adjacent such a horizontal void. In one embodiment, such a horizontal void is excavated across less than the entire width of the retort site, leaving ''side pillars'' of unfragmented formation spaced inwardly from adjacent side boundaries of the retort site at opposite sides of such a horizontal void. This reduces the maximum span of the horizontal void, when compared with supporting overburden above the void with one or more interior isolated pillars spaced inwardly from the side boundaries of the retort. The side pillars are explosively expanded. Then such a zone of unfragmented formation is explosively expanded toward such a horizontal void for forming a fragmented permeable mass of formation particles containing oil shale in the retort. The resulting fragmented mass can have a slightly narrowed region along the sides where the side pillars were present.

• Assignee: Occidental Oil Shale Inc.
• Patent Number(s): US 4453769
• OSTI ID: 6482842
• 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
FRAGMENTATION
FUELS
IN-SITU PROCESSING
IN-SITU RETORTING
MATERIALS
MECHANICAL STRUCTURES
NATURAL OCCURRENCE
OIL SHALES
PROCESSING
RETORTING
SUPPORTS
VOIDS