The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 25, 1981
Filed:
Feb. 01, 1980
Bernard E Weichman, Houston, TX (US);
Multi Mineral Corporation, Houston, TX (US);
Abstract
A method for the in situ processing of mineral-bearing oil shale ore includes the establishment of a plurality of underground stopes by removing from each a portion of the oil shale ore therein, rubblizing the remaining ore in each stope, extracting the rubblized ore and crushing it to obtain a nahcolite fraction and an oil shale fraction having a desired particle size for subsequent processing, and restoring sized oil shale particles to the stope by back filling the stope as the rubble is extracted so as to maintain the stope substantially filled with particles to provide lateral support to the side walls and reduce the likelihood of caving in the stope. The nahcolite fraction is recovered from the crushed ore prior to backfilling of the stopes for retorting to recover shale oil, while soda ash and alumina may be recovered from the spent shale by leaching the stopes after retorting. A method of retorting is also disclosed in which three retorts are operated in series, the first retort comprising a gas heating retort, the second a carbon recovery retort and the third an active retort.