Explosive fracturing of deep rock
A fracture network is produced in deep rock, e.g., in an ore body, by detonating explosive charges sequentially in separate cavities therein, the detonations producing a cluster of overlapping fracture zones and each detonation occurring after liquid has entered the fracture zones produced by previous adjacent detonations. High permeability is maintained in an explosively fractured segment of rock by flushing the fractured rock with liquid, i.e., by sweeping liquid through the fracture zones with high-pressure gas, between sequential detonations therein so as to entrain and remove fines therefrom. Ore bodies prepared by the blast/flush process with the blasting carried out in substantially vertical, optionally chambered, drilled shot holes can be leached in situ via a number of holes previously used as injection holes in the flushing procedure and a number of holes which are preserved upper portions of the shot holes used in the detonation process. In the leaching of ore, fines are removed from fractures therein by intermittent or continuous flushing of the ore with lixiviant and high-pressure gas, e.g., air, using, in the case of the in situ leaching of an explosively fractured ore body, a lateral and upward flow of lixiviant from zones that have been less severely, to others that have been most severely, worked by multiple detonations in the ore body.
- Assignee:
- E. I. Du Pont de Nemours and Co.
- Patent Number(s):
- US 3902422
- OSTI ID:
- 7286391
- Country of Publication:
- United States
- Language:
- English
Similar Records
Method of explosive fracturing of a formation at depth
Method and apparatus for mixing gaseous oxidant and lixiviant in an in-situ leach operation
Related Subjects
450100* -- Military Technology
Weaponry
& National Defense-- Chemical Explosions & Explosives
CHEMICAL EXPLOSIONS
COMMINUTION
COPPER
ELEMENTS
EXPLOSIONS
EXPLOSIVE FRACTURING
FRACTURING
IN-SITU PROCESSING
METALS
NICKEL
ORES
PROCESSING
ROCKS
SILVER
TRANSITION ELEMENTS
USES