Determining the locus of a processing zone in an oil shale retort by effluent water composition
US4223726A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 28, 1979 |
| Grant date | Sep 23, 1980 |
| Priority date | — |
| Expiry date | Feb 28, 1999 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B43/247
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A processing zone advances through a fragmented permeable mass of particles containing oil shale in an in-situ oil shale retort in a subterranean formation containing oil shale. The retort has an effluent water passing therefrom. The effluent water carries a constituent which is formed, by advancement of the processing zone through the fragmented mass, from a precursor contained in the formation. In a first aspect of the invention, the locus of the processing zone is determined by assaying the formation at selected locations in the retort for content of the precursor before processing the selected locations, and effluent water from the retort is monitored for concentration of the selected constituent. For example, the nitrogen content of kerogen can be the precursor and effluent water from the retort can be monitored for the concentration of ammonia and/or ammonium sulfate produced by retorting of kerogen in the oil shale. In the second embodiment of the invention, recognition is made of the correlation between the Fischer Assay of the oil shale and the amount of water it contains. Core samples of the formation are analyzed prior to processing to determine the water content and the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.