Shale diesel fuel

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). 

Cowan MJ, Jenkins LJ Jr. 1981. Navy toxicity study of shale and petroleum JP-5 aviation fuel and diesel fuel marine. In Griest WH, Guerin MR, Coffin DL, eds. Health effects investigation of oil shale development. Ann Arbor, MI Ann Arbor Science Publishers, Inc., 129-139. 

The total yield of diesel fuels was 51.6 volume-percent of the in situ crude. The properties of these fuels fell within the limits (Table V) of those of corresponding petroleum diesel fuels currently marketed in the United States (8) except for the carbon residue of the S-M shale-oil diesel fuel this residue was slightly higher than those of the petroleum diesel fuels but was probably acceptable. The value of 0.36 weight-percent for the carbon residue on the 10-percent bottoms of the S-M fuel was only a... 

The sulfur percentages of 0.02 weight-percent or less in the shale oil diesel fuels would permit these fuels to be classed as low-sulfur diesel fuels. Nitrogen percentages were low, ranging from 141 to 202 parts per million (ppm). Cetane indexes, calculated by ASTM method D-976 (7j, were excellent, ranging from 48 to 56. 

Table VI shows the range of properties of grades 1, 2, and 4 burner fuel oils marketed in the United States in 1974 (9). Most of these fuels were also marketed as diesel fuels (JJ,9). The shale-oil types C-B and T-T diesel fuels would, respectively, fit with the grades 1 and 2 burner fuels. The shale-oil S-M diesel fuel would also fit with the grade 2 burner fuels. The shale-oil fuel oil fraction had a distillation range resembling the grade 2 fuels, but its viscosity was intermediate between those of the grade 2 and grade 4 fuels.

The C-B, T-T, and S-M shale oil diesel fuels respectively met the ASTM requirements (7) for grades 1-D, 2-D, and 4-D diesel fuels and Nos. 1, 2, and 4 fuel oils, with some minor exceptions. Thus, the 90-percent distillation temperature of the T-T diesel fuel was 3° F lower than the ASTM lower limit for grade 2-D diesel and No. 2 fuel oil. Also, the viscosity of the S-M diesel fuel was slightly lower than the lower limit specified for grade 4-D... 

The cobalt molybdate catalyst is also suitable for the reduction of organic nitrogen bases (30). From Colorado-shale-oil fractions containing 2% N2 and 0.7% sulfur, jet and Diesel fuels have been obtained with 0.01 to 0.1% N2 and 0.03 to 0.04% sulfur. 

Once the synthetic crude oils from coal and oil shale have been upgraded and the heavy ends converted to lighter distillates, further refining by existing processes need not be covered in detail except to note the essential character of the products. The paraffinic syncrude from oil shale yields middle distillates which are excellent jet and diesel fuel stocks. The principal requirements are removal of nitrogen to the extent necessary for good thermal stability of the fuels and adjustment of cut points to meet required pour or freeze points, limited by the presence of waxy straight-chain paraffins. The heavy naphtha from shale oil can be further hydrotreated and catalytically reformed to acceptable octane number, but with considerable loss of volume because of the only moderate content of cyclic hydrocarbons, typically 45-50%. On the other... 

Table IV. Comparison of Diesel Fuels from Processed Shale Oil...

A flow diagram for a proposed shale oil refinery is shown in Figure 5. An FCC unit is used as the primary cracking process. This refinery produces high-octane gasoline and diesel fuel. Jet fuel also could be produced by severely hydrogenating a kerosene cut (10) from the whole-oil hydrotreater or by using a hydrocracker in place of the FCC. The... 

Cottingham, P. L. Diesel Fuels from Shale Oil, Symposium on Alternate... 

The hydrotreated shale oil is fractionated by distillation methods into gasoline, jet, diesel, and 650°F bottoms (residua). The jet and diesel fuel boiling ranges were determined experimentally to meet flash point and freeze or pour point requirements. Some of the residua was recycled back to the hydrotreater to increase jet and diesel fuel yields. 

The bulk of the Navyfs vehicles utilize middle distillate fuels a kerosene type jet fuel, JP-5, for aircraft and diesel fuel marine, DFM, for ships and boats. Reasonable yields of these fuels can be obtained from shale oil. Further, shale crude oil has a good hydrogen content which allows upgrading to finished fuel with modest additions of expensive hydrogen. Thus the interest in Navy fuels from shale oil. 

Testing of the Shale-II JP-5 jet fuel, which is currently underway in four different gas turbine engines, shows good combustion performance. No problems have been encountered. Likewise, testing of ship steam boilers, marine gas turbines, and diesel engines on the Shale-II diesel fuel marine (DFM) is demonstrating highly acceptable performance. 

The U.S. Navy has been involved for some time in the development of Navy fuels from alternative sources (shale oil, tar sands and coal). As a part of this effort, the Naval Research Laboratory and the Naval Air Propulsion Center have been studying the characteristics of these fuels (.1, 2). NKL and NAPC are currently participating in a program to characterize the products from the Shale-II refining process conducted by the Standard Oil Company of Ohio (SOHIO) at their refinery in Toledo, Ohio. This paper is concerned with a part of this program and is a surrmary of the work on the physical and related properties of three military type fuels derived from shale JP-5 and JP-8 jet turbine fuels, and diesel fuel marine (DEM) (3, 5). Another paper of this symposium (6) will discuss the chemical characterization of the fuels. 

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