Kerogen yields

Oil Shale Oil shale is nonporous rock containing organic kero-gen. Raw shale oil is extracted from mined rock by pyrolysis in a surface retort, or in situ by steam injection after breaking up the rock with explosives. Pyrolysis cracks the kerogen, yielding raw shale oil... 

Figure 5. Variation in absolute yields of 2,3-dimethylthiophene, n-non-l-ene and 1,2-dimethylbenzene (/ig/mg kerogen) with depth for the Monterey Fm. kerogens. Yields determined from FID chromatograms after co-pyrolysis of the kerogens with known amounts of poly-/ -f-butylstyrene (Larter and Senftle, 44).

Shale, a sedimentary rock, can contain kerogen, a complex, fossilized, organic polymerized material. By distilling shale, the kerogen yields shale oil (68308-34-9) and other petroleum products (shale can also be impregnated with petroleum, but this is not shale oil). 

Kerogen Decomposition. The thermal decomposition of oil shale, ie, pyrolysis or retorting, yields Hquid, gaseous, and soHd products. The amounts of oil, gas, and coke which ultimately are formed depend on the heating rate of the oil shale and the temperature—time history of the Hberated oil. There is Htde effect of shale richness on these relative product yields under fixed pyrolysis conditions, as is shown in Table 5 (10). 

The kerogen content of different oil shales, i.e., the average yield of oil of an oil shale can vary greatly. Most oil shales have oil yields between 50 and 150 1 oil/t oil shale, rich shales may even yield more than 200 1/t. A particular characteristic of oil shale is its high areal density, which can exceed 1 million b/acre at its thickest (Bunger et al., 2004). Oil shale can also be used directly as fuel for electricity generation, as, for instance, in Estonia. However, oil shale is characterised by a low calorific value between 7.5 and 9 MJ/kg (based on LHV), which is about one fifth of the energy content of crude oil (Porath, 1999). 

The HS yields from the pelletal and matricial OM (Table 1) shows a high content of humic compounds isolated from pellets (humic carbon up to 75% of TOC) and a lower one in adjacent sediments (humic carbon less than 21% of TOC), along with the higher content of HU (low mature kerogen) in surrounding sediments and the lowest in the pellets. 

The results are described in several sections. The first section deals with gross variations in organic sulfur with maturity as determined by Py-GC. The relationship between organic sulfur and Rock-Eval Tmax is discussed in the second section. In the third section, yields from flash pyrolysis are used to determine kinetic parameters for the loss of precursors for organic sulfur and other compounds from the kerogen during maturation. The last section describes the maturity-related variations in organic sulfur pyrolysis products. 

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