Shale fuels

Bondar, E. Koel, M. 1998. Application of supercritical fluid extraction to organic geochemical studies of oil shale. Fuel, 77, 211-213. 

Jaganathan, J., Mohan, M.S. and Zingaro, R.A. (1986) Identification of arsenic-bearing minerals in a sample of Green River oil shale. Fuel, 65(2), 266-69. 

Dieckmann V., Schenck H.J., Horsfield B., Welte D.H. (1998) Kinetics of petroleum generation and cracking by programmed-temperature closed-system pyrolysis of Toarcian shales. Fuel 77, 23-31. 

The composition of shale fuels may vary widely, however, depending on the overall refining process. Much work is needed to explore other refining options and to examine the effect of refining on finished fuel composition and properties. 

High Temperature (Thermal) Stability. The high temperature stability of the Shale-I jet fuels was measured using the JFTOT technique (8 ). The thermal oxidative stability of the received fuel (976 ppm N) was measured. The fuel was then acid extracted, the isolated basic nitrogen compounds added back into the extracted shale fuel in varying quantity, and the thermal oxidative stability redetermined. A petroleum derived JP-5 was also subjected to JFTOT... 

Williams, P. F. Thermogravimetry and Decomposition Kinetics of British Kimmeridge Clay Oil Shale. Fuel 64 (1985) p. 540-545. 

Alternative feedstocks for petrochemicals have been the subject of much research and study over the past several decades, but have not yet become economically attractive. Chemical producers are expected to continue to use fossil fuels for energy and feedstock needs for the next 75 years. The most promising sources which have received the most attention include coal, tar sands, oil shale, and biomass. Near-term advances ia coal-gasification technology offer the greatest potential to replace oil- and gas-based feedstocks ia selected appHcations (10) (see Feedstocks, coal chemicals). 

In addition to the significant consumption of coal and lignite, petroleum, and natural gas, several countries utilize modest quantities of alternative fossil fuels. Canada obtains some of its energy from the Athabasca tar sands development (the Great Canadian Oil Sands Project). Oil shale is burned at... 

As of this writing natural gas is a plentiful resource, and there has been a marked tendency not to use other fossil fuels as SNG sources. However, petroleum and oil shale (qv) have been the subject of extensive research efforts. These represent other sources of gaseous fuels and are worthy of mention here. 

Coal, tar, and heavy oil fuel reserves are widely distributed throughout the world. In the Western hemisphere, Canada has large tar sand, bitumen (very heavy cmde oil), and coal deposits. The United States has very large reserves of coal and shale. Coal comprises ca 85% of the U.S. recoverable fossil energy reserves (6). Venezuela has an enormous bitumen deposit and Brazil has significant oil shale (qv) reserves. Coal is also found in Brazil, Colombia, Mexico, and Pern. Worldwide, the total resource base of these reserves is immense and may constitute >90% of the hydrocarbon resources in place (see... 

Shale Oil. In the United States, shale oil, or oil derivable from oil shale, represents the largest potential source of Hquid hydrocarbons that can be readily processed to fuel Hquids similar to those derived from natural petroleum. Some countries produce Hquid fuels from oil shale. There is no such industry in the United States although more than 50 companies were producing oil from coal and shale in the United States in 1860 (152,153), and after the oil embargo of 1973 several companies reactivated shale-oil process development programs (154,155). Petroleum supply and price stabiHty has since severely curtailed shale oil development. In addition, complex environmental issues (156) further prohibit demonstration of commercial designs. 

Alternative fuels fall into two general categories. The first class consists of fuels that are made from sources other than cmde oil but that have properties the same as or similar to conventional motor fuels. In this category are fuels made from coal and shale (see Fuels, synthetic). In the second category are fuels that are different from gasoline and diesel fuel and which require redesigned or modified engines. These include methanol (see Alcohol fuels), compressed natural gas (CNG), and Hquefted petroleum gas (LPG). 

Production of synthetic fuels from coal, oil shale, and methane involves changing the chemical stmcture of the raw material, especially the... 

Oil shale deposits were formed in ancient lakes and seas by the slow deposition of organic and inorganic remains. The geology and composition of the inorganic minerals and organic kerogen components of oil shale vary with deposit locations throughout the world (1) (see also Fuel RESOURCES Petroleum). 

Gas Combustion Retort. The continuous gas combustion retort (GCR) has been modeled after the earlier batch-operation NTU retort. Although the term "gas combustion" has been appHed to this process, it is a misnomer in that, in a weU-designed and properly operated system, the residual char on the retorted shale suppHes much of the fuel for this process. The GCR is the foremnner of most continuous AGR processes (Table 7). 

In Estonia, most of the rich oil shale, 209 L/1 kukersite, is burned as a soHd fuel to produce electric power (37). The kukersite, although technically an oil shale, is actually similar to a high ash, low grade coal (qv) ideally suited for this use. 

The number of commercial oil shale operations woddwide has decreased significandy since the decade 1975—1985 and are producing only a fraction of the wodd s hquid fuels needs. Most commercial oil shale operations have been scaled back. 

The UPI and MI retorts are processing 7000 t/d (7700 short tons/d) of Irati shale to produce 24,381 m /d (3870 bbl) of shale as well as 80 t (55 short tons) of LPG, 132 t (145 short tons) of clean fuel gas, and 98 t (108 short tons) of sulfur. The SIX plant has reached its design rate (Table 16) in an energy efficient manner with a high on-stream (operating) factor. 

Oil Shale Operations in Israel. Oil shale, the only fossil fuel resource in Israel, is being used to generate electric power. The oil shale feed stock, typical of the low grade IsraeH oil shale (see Table 2), is situated in a deposit overlying phosphate ore. The oil shale operations are being carried out because the oil shale has to be mined to obtain the phosphate ore. 

Shale ok production in the former Soviet Union is also declining. The orky significant shale ok operations are in Estonia. Most of the rich (208 L/1 (50 gal/short ton)) Estonian ok shale is combusted directly as fuel. 

H. Batrick and co-workers. Final Report—The Production and Refining of Crude Shale Oil into Military Fuels, AppHed Systems Corp. for Office of Naval Research, Washington, D.C., Aug. 1975. 

Petroleum refining, also called petroleum processing, is the recovery and/or generation of usable or salable fractions and products from cmde oil, either by distillation or by chemical reaction of the cmde oil constituents under the effects of heat and pressure. Synthetic cmde oil, produced from tar sand (oil sand) bitumen, and heavier oils are also used as feedstocks in some refineries. Heavy oil conversion (1), as practiced in many refineries, does not fall into the category of synthetic fuels (syncmde) production. In terms of Hquid fuels from coal and other carbonaceous feedstocks, such as oil shale (qv), the concept of a synthetic fuels industry has diminished over the past several years as being uneconomical in light of current petroleum prices. 

Synthetic Fuels. Hydrocarbon Hquids made from nonpetroleum sources can be used in steam crackers to produce olefins. Fischer-Tropsch Hquids, oil-shale Hquids, and coal-Hquefaction products are examples (61) (see Fuels, synthetic). Work using Fischer-Tropsch catalysts indicates that olefins can be made directly from synthesis gas—carbon monoxide and hydrogen (62,63). Shape-selective molecular sieves (qv) also are being evaluated (64). 

Synthetic fuels derived from shale or coal will have to supplement domestic suppHes from petroleum someday, and aircraft gas turbine fuels producible from these sources have been assessed. Shale-derived fuels can meet current specifications if steps are taken to reduce the nitrogen levels. However, extracting kerogen from shale rock and denitrogenating the jet fuel are energy-intensive steps compared with petroleum refining it has been estimated that shale jet fuel could be produced at about 70% thermal efficiency compared with 95% efficiency for petroleum (25). Such a difference represents much higher cost for a shale product. 

Production of Hquid jet fuel from processing of abundant natural gas is a more promising and cheaper source of high quaUty product than shale or... 

---