Ground water control for an in situ oil shale retort

Patent · Tue May 08 04:00:00 EDT 1979

OSTI ID:6083520

Ridley, R D

An in situ oil shale retort is formed in a subterranean formation containing oil shale. The retort contains a fragmented permeable mass of particles containing oil shale. An open base of operation is excavated in the formation above the retort site, and an access drift is excavated to the bottom of the retort site. Formation is explosively expanded to form the fragmented mass between the access drift and an elevation spaced below the bottom of the base of operation, leaving a horizontal sill pillar of unfragmented formation between the top of the fragmented mass and the bottom of the base of operation. The sill pillar provides a safe base of operation above the fragmented mass from which to control retorting operations. A plurality of blasting holes used in explosively expanding the formation extend from the base of operation, through the sill pillar, and open into the top of the fragmented mass. Trenches are formed in the base of operation for collecting ground water which enters the base of operation prior to and during retorting operations, and collected ground water is withdrawn from the base of operation. Casings can be placed in the blasting holes and adapted for controlling gas flow through the fragmented mass during retorting operations. The casings extend above the floor of the base of operation to inhibit flow of ground water through the blasting holes into the fragmented mass, and other blasting holes not having such casings are sealed. After retorting is completed, the floor of the base of operation can be covered with a layer of concrete and/or the blasting holes can be sealed with concrete to inhibit leakage of ground water into treated oil shale particles in the fragmented mass.

• Assignee: Occidental Oil Shale, Inc.
• Patent Number(s): US 4153297
• OSTI ID: 6083520
• 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
CONTROL
ENERGY SOURCES
FOSSIL FUELS
FUELS
GROUND WATER
HYDROGEN COMPOUNDS
IN-SITU PROCESSING
IN-SITU RETORTING
OIL SHALES
OXYGEN COMPOUNDS
PROCESSING
RETORTING
WATER