Oil shale utilization

Lanzirotti, A., Sutton, S.R. et al. (2006) Spatial and temporal variability of arsenic solid-state speciation in historically lead arsenate contaminated soils. Environmental Science and Technology, 40(3), 673-79. 

and Nriagu, J.O. (1994) Arsenic historical perspectives, in Arsenic in the Environment Part E Cycling and Characterization (eds J.O. Nriagu), John Wiley Sons, Ltd, New York, pp. 1-15. 

Bashkin, V.N. and Wongyai, K. (2002) Environmental fluxes of arsenic from lignite mining and power generation in northern Thailand. Environmental Geology, 41(8), 883-88. 

Ben Zirar, S., Gibaud, S., Camut, A. and Astier, A. (2007) Pharmacokinetics and tissue distribution of the antileukaemic organoarsenicals arsthinol and melarsoprol in mice. The Journal of Organometallic Chemistry, 692(6 Special Issue), 1348-52. 

and Jonasson, I.R. (1973) Geochemistry of arsenic and its use as indicator element in geochemical prospecting. The Journal of Geochemical Exploration, 2(3), 251-96. 

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Arsenic in coal and oil shale utilization and their by-products... 

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... 

Colorado during the period 1980-1991, with an average yield of 110 L shale oil per tonne of exploitable oil shale (Dyni 2000). The facility has a capacity of 1 600 000 L shale oil per day (10000 barrels/d Press Siever 1997). However, most of the oil shale mined in the world today is utilized as feedstock for production of energy, both thermal and electrical. In such power plants, the temperatures reach up to 1500 °C. As an example, Estonian energy production accounts for about 70% of the world s oil shale consumption (Ots Uus 2002). 

Arro, H., Prikk, A., Pihu, T. Opik, I. 2002. Utilization of semi-coke of Estonian shale oil industry. Oil Shale, 19, 117-125. 

Utilization of coal and oil shale to produce liquid and gaseous synfuels results in the generation of many hazardous sub-tances. Workers in these synfuel plants are likely to be exposed to potentially carcinogenic materials present in coal tars and oils. Among the various pathways of exposure, skin contamination by direct contact transfer or by adsorption of vapors and particulates into the skin presents a serious occupational health hazard. The skin irritant and potential carcinogenic properties of raw syncrudes and their distillate fractions have been reported (1. 2, 3). 

We will examine three synthetic fuel scenarios and compare their implications regarding sulfur availability with the current and projected market for sulfur to the year 2000. The analysis will consider three production levels of synthetic fuels from coal and oil shale. A low sulfur Western coal will be utilized as a feedstock for indirect liquefaction producing both synthetic natural gas and refined liquid fuels. A high sulfur Eastern coal will be converted to naphtha and syncrude via the H-Coal direct liquefaction process. Standard retorting of a Colorado shale, followed by refining of the crude shale oil, will round out the analysis. Insights will be developed from the displacement of imported oil by synthetic liquid fuels from coal and shale. 

This consideration as well as those concerning cost, convenience of use, and availability leads to the conclusion that petroleum fuels will be used for transportation purposes in preference to other fuels as long as crude petroleum is available. Although liquid fuels can be produced from gas, coal, or shale oil, the high energy losses involved in the conversion make such operations unattractive from an energy conservation point of view. Obviously, the direct utilization of gas and coal as produced and of the type of crude oil which can be produced from oil shale by simple retorting is the most desirable procedure and should be followed until petroleum is so scarce or expensive to find that the free play of economic forces dictates the synthesis of liquid fuels. 

This does not mean that research should not be conducted in the synthesis of liquid fuels. This type of research should be conducted on a rational basis rather than, as in the early 1920 s and late 1940 s, on a basis of fear that petroleum supplies are running out. The efficiency of current synthesis operations is low—in the range of 40 to 60%. These efficiencies can be improved and, while this is being accomplished, it is reasonable to predict that petroleum prospecting and production will become more costly. Consequently there is a logical meeting point in the future, indistinct at the moment, where synthesis operations may logically be utilized. When this situation develops, natural gas supplies will probably also be limited and coal, oil shale, and tar sands will constitute the basic raw materials. 

Another subtractive pre-column which shows potential utility is molecular sieve 5A. This material is known to selectively subtract straight chain organic species, although compounds other than alkanes are removed. Table II shows results obtained at different final pyrolysis temperatures for oil shale samples pyrolyzed in the thermal chromatograph. 

Costa Neto, C. "Perspectives for the utilization of oil shales in Brazil, Projeto Xistoquimica - Univ. Fed. Rio de Janeiro, Rio de Janeiro, 1978 (in Portuguese). 

The Maastrichtian (latest Cretaceous) Israeli oil shales consist of four main groups of components organic matter biogenic calcite and apatite detrital clay minerals and quartz, with a little amount of authigenic pyrite and feldspar. The main chemical characteristics of the oil shales are reviewed,with an emphasis on those which may affect future utilization techniques. 

Future successful utilization of the Israeli oil shales, either by fluidized-bed combustion or by retorting will contribute to the State s energy balance. 

The results presented are not part of a systematic study of oil shale pyrolysis but rather those of various experiments selected to demonstrate the utility and potential of the method. 

Nahcolite is not currently mined. However, approximately 30 billion tons (27 billion metric tons) of nahcolite are known to be associated with western oil-shale deposits. A study conducted by TRW, Inc., (2) indicates that commercial production of nahcolite for FGD applications would be merited provided a utility market of a least 5000 MW existed. This is equivalent to 1.28 million tons per year (1.16 million metric tons per year) of nahcolite, assuming the use of 1% sulfur coal with 70% SO2 removal. 

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