Method for forming uniform flow rubble bed
US4533181A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 29, 1984 |
| Grant date | Aug 6, 1985 |
| Priority date | — |
| Expiry date | Mar 29, 2004 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21C41/24
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An in situ oil shale retort containing a fragmented permeable mass of formation particles having a generally uniform permeability across horizontal cross-sections of the retort is provided. To form the retort, a void is excavated in a subterranean formation within the boundaries of the retort site, while at least one zone of unfragmented formation is left adjacent the void. A plurality of explosive charges are placed in the zone of unfragmented formation in a selected pattern; an array of central explosive charges and a plurality of perimeter charges arranged in rows surrounding the central charges. The spacing distance between each row of perimeter charges and an adjacent outer row of central charges is about equal. The combination of spacing distance and powder factor of the central charges is selected to produce a center portion of the fragmented permeable mass having a first average particle size (d.sub.1) and a first average void fraction (e.sub.1). The powder factor for each row of perimeter charges and the spacing distance between each outer row of central charges and an adjacent row of perimeter charges is selected to produce a perimeter portion of the fragmented permeable …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.