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Oil shale project run summary, small retort runs S-21 and S-23

Technical Report ·
OSTI ID:6490159

The objective of Runs S-21 and S-23 was to assess the technical feasibility of using oxygen diluted, respectively, with steam or carbon dioxide as the injection gas for MIS oil shale retorting. The motivation for using oxygen rather than air is the production of a much higher value offgas. In contrast to the nitrogen diluent present in air, steam and CO/sub 2/ can be removed readily, by condensation or absorption, from the valuable hydrocarbon and hydrogen species in the offgas. Furthermore, steam enhances hydrogen production and, coupled with the steam condensation, could result in offgas hydrogen concentrations sufficient to warrant recovery of hydrogen for hydrotreating the product oil. Carbon dioxide is expected to be not only a major product from MIS retorting but could also be available in concentrated form by absorptive separation from the retort effluent. Residual gas from such absorption, rich in carbon monoxide, could be used for hydrogen production in a separate unit. It is concluded that oxygen, diluted about 9/1 (v/v) with either steam or CO/sub 2/, appears to be technically feasible as an injection gas for MIS retorting. At this concentration and at the flux tested (0.07 m/sup 3//m/sup 2/ min O/sub 2/), both operations proceeded smoothly with acceptable maximum temperature. Retorting rates were comparable - about 2.2 m/day. Offgas lower heating values (LHV) (600 to 700 Btu/SCF), on a CO/sub 2/-and H/sub 2/S free basis, are much higher than those obtained with air as injection gas. As an example, the offgas from Run S-13 (equimolar steam/air; similar O/sub 2/ flux and shale), on the same basis, contained about 84 v% nitrogen and had an LHV of about 91 Btu/SCF. No significance is attached to the difference in oil yield between S-21 and S-23 in view of the difficulty in S-21 of separating product oil from the large volume of coproduct water.

Research Organization:
California Univ., Livermore (USA). Lawrence Livermore Lab.
DOE Contract Number:
W-7405-ENG-48
OSTI ID:
6490159
Report Number(s):
UCID-19082; ON: DE81026035
Country of Publication:
United States
Language:
English