Method for rubblizing an oil shale deposit for in situ retorting

Patent · Tue Apr 12 04:00:00 EST 1977

OSTI ID:7309390

Lewis, A E

A method for rubblizing an oil shale deposit that has been formed in alternate horizontal layers of rich and lean shale includes the steps of driving a horizontal tunnel along the lower edge of a rich shale layer of the deposit, sublevel caving by fan drilling and blasting of both rich and lean overlying shale layers at the distal end of the tunnel to rubblize the layers, removing a substantial amount of the accessible rubblized rich shale to permit the overlying rubblized lean shale to drop to tunnel floor level to form a column of lean shale, performing additional sublevel caving of rich and lean shale toward the proximate end of the tunnel, removal of a substantial amount of the additionally rubblized rich shale to allow the overlying rubblized lean shale to drop to tunnel floor level to form another column of rubblized lean shale, similarly performing additional steps of sublevel caving and removal of rich rubble to form additional columns of lean shale rubble in the rich shale rubble in the tunnel, and driving additional horizontal tunnels in the deposit and similarly rubblizing the overlying layers of rich and lean shale and forming columns of rubblized lean shale in the rich, thereby forming an in situ oil shale retort having zones of lean shale that remain permeable to hot retorting fluids in the presence of high rubble pile pressures and high retorting temperatures. 10 claims, 8 figures.

• Assignee: Energy Research and Development Administration
• Patent Number(s): US 4017119
• OSTI ID: 7309390
• Country of Publication: United States
• Language: English

Related Subjects

04 OIL SHALES AND TAR SANDS
040300 -- Oil Shales & Tar Sands-- Drilling
Fracturing & Mining
040401* -- Oil Shales & Tar Sands-- In Situ Methods
True & Modified
BITUMINOUS MATERIALS
CARBONACEOUS MATERIALS
COMMINUTION
CRUSHING
DRILLING
ENERGY SOURCES
EXCAVATION
FOSSIL FUELS
FRAGMENTATION
FUELS
GEOLOGIC DEPOSITS
IN-SITU PROCESSING
IN-SITU RETORTING
OIL SHALE DEPOSITS
OIL SHALES
PROCESSING
RESOURCES
RETORTING
ROCK DRILLING
TUNNELS