Method of extracting liquid and gaseous fuel from oil shale and tar sand
US4266609A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jun 15, 1979 |
| Grant date | May 12, 1981 |
| Priority date | — |
| Expiry date | Jun 15, 1999 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B36/04
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Kerogen and other combustible matter can be extracted from an area of oil shale or tarsand by drilling boreholes in a selected pattern through the overlying soil and rock without removing it. Each borehole mouth is tightly closed by a cover provided with an air inlet pipe and a gas exhaust pipe. In the covers of one or several boreholes, the inlet pipe is centrally guided and longitudinally movable in an upward and downward direction, and a laser beam generated by a laser source is inroduced into the upper end of the pipe and directed centrally to its bottom where it is diverted toward the borehole wall by a mirror assembly. The laser beam moved along the borehole wall irradiates the oil shale or tarsand and ignites the combustible matter contained therein which liquefies and evaporates. Combustion spreads from the initially ignited bore to the remaining bores in the area through the fissures in the formation and likewise serves to liquefy and evaporate the kerogen there. The combustion is maintained by pressurized air or oxygen introduced through the air inlet pipe, which also serves to cool the mirror assembly. The pressure thus created drives the evaporated kerogen out of the bo…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.