skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Partitioning of major, minor, and trace elements during simulated in-situ oil shale retorting

Technical Report ·
OSTI ID:5234247

The fate of inorganic constituents in Green River, Antrim, and Moroccan oil shales during in-situ retorting has been investigated. The partitioning or distribution of 50 elements to the spent shale, shale oil, retort water, and gases was studied by completing mass balances for several runs of three simulated in-situ retorts. Byproducts and products from 24 simulated in-situ retort runs were analyzed. The effect of shale origin and retort operating conditions, including temperature, particle size, atmosphere, and gas flow rate, on partitioning patterns was investigated, and the resulting data were used to develop a conceptual model of elemental partitioning during simulated in-situ retorting. Most of the 50 elements studied are not significantly mobilized during in-situ retorting. The only elements that are distributed in large quantities to the by-products are C, H, N, S, Cd, and Hg. Lesser but environmentally significant quatities of Se, As, Ni, and Co are distributed to the oils and waters, and at retorting temperatures in excess of about 900/sup 0/C, Se is mobilized to the gas phase. Mercury and Cd were the most mobile trace metals studied. About 70% of the Hg and 30% of the Cd were distributed to the gas phase. Mercury was released as a series of pulses in the last third of a retort run. Thermodynamic calculations indicated that elemental Hg is the major stable gas-phase species in all zones of an in-situ retort. The work demonstrated that elemental partitioning is controlled by the mineral residence of an element and the retort operating conditions employed. Significant differences were observed in the mobility and partitioning patterns of Green River, Antrim, and Moroccan oil shales. The only retorting conditions that had a statistically significant effect on partitioning patterns were temperature, input gas, particularly steam, and retort design and operation.

Research Organization:
California Univ., Berkeley (USA). Lawrence Berkeley Lab.
DOE Contract Number:
W-7405-ENG-48
OSTI ID:
5234247
Report Number(s):
LBL-9062
Resource Relation:
Other Information: Thesis
Country of Publication:
United States
Language:
English