Inorganic sulfur species in waste waters from in situ oil shale processing

Abstract

Thiosulfate and thiocyanate were found to be important solutes in four waste waters derived from combustion type in situ processing of oil shale. Thiosulfate, thiocyanate, tetra‐thionate, sulfite, sulfate and total sulfur concentrations were determined, and the predominant sulfur species in all waste‐water samples was thiosulfate, ranging from 420 to 2,200 mg/L. Thio‐cyanate levels ranged from 24 to 730 mg/L. Hydrogen sulfide has been reported in gases derived from the retorting of oil shale, but sulfide was not detected in any of the waters studied.

Analysis of water associated with an in situ retort one year after oil production has shown that thiocyanate can persist in ground waters remaining in retorted zones. Some similarities in the composition of wastes from the in situ retorting of oil shale and the ammoniacal liquors produced during coking of coal are noted.

Key words:

• Oil Shale
• Waste Water
• Thiosulfate
• Thiocyanate

Notes

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