Eastern coals

A notable feature of the Western Canadian coals is their low sulphur content (usually <0.5%) which tends, however, to be partly offset by higher mineral matter contents than are associated with the Eastern coals. As well, bituminous coals in the mountain belts are typically deficient in vitrinite, which often represents less than 50% of the coal "substance" and only occasionally reaches 70-75%, but this is compensated by the fact that their micrinites and semifusinites tend to be "reactive" constituents when the coals are carbonized. Notwithstanding their low fluidity (rarely >1000 dd/min), Western mvb coals therefore make excellent metallurgical cokes when carbonized in suitably proportioned blends. 

A typical, modem, coal-fired power plant emits 25 pg nickel per Megajoule (MJ) of power produced, compared with 420 pg/MJ for an oil-fired plant (Hasanen et al. 1986). The nickel concentration in stacks emissions from a modem coal-fired power plant with an electrostatic precipitator was 1.3 pg/m (Lee et al. 1975). High-sulfur eastern coal has a higher nickel content than low-sulfur western coal, so power plants using eastern coal emit more nickel than those using western coal (QueHee et al. 1982). 

Eastern coal conversion development may come to be favored because of market proximity, water availability, and coal sources which, because of their high sulfur content, are currently unuse-able and, hence, largely decoupled from other energy prices. Proximity reduces transport costs and allows an increased use of low and medium Btu syngas processes. Reactivity and swelling problems may be overcome by technology. 

A single energy refinery would require about 20,000 tons/day of high-sulfur Eastern coal, producing about 600 long tons/day of elemental sulfur by-product. For the purposes of this paper, the future price of sulfur has been projected to be about 100/LT, with a floor provided by the energy cost to produce discretionary sulfur. At this sale price, the sulfur by-product credit is about 0.25/million Btu of energy produced. This credit, for 2 million... 

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. 

Plants with a different biochemistry are found in fresh water environments, as compared to marine environments. They decay to different products and the resultant peat will have a lower sulfur content. However, it is the fresh water contact that provides the general explanation of the low sulfur content of Western U.S. coals, and the saline water contact that provides the general explanation of the high sulfur content of the Eastern coals (Figure 1). Further evidence of this phenomenon is that those Eastern coal beds that have high sulfur content are overlain with marine shale or limestone, whereas the low sulfur coal beds are not (3, 14). 

Cs are more depleted in western coals. Silicon is also depleted in coal, probably because of the presence of clay minerals. Most lithophile elements (i.e., those normally associated with the earth s crust) have EF values near one, but it is interesting that the rare earth elements show slightly, but consistently higher enrichments in eastern coal. The apparent depletion of Ta is probably not real, but an artifact resulting from Wedepohl s use of too large a crustal abundance for it (14). 

A comparison of fine and coarse particle compositions supports this hypothesis. Figure 4 shows EFcrust values for fine and coarse particles from six eastern-coal-burning plants equipped with ESPs. (We wanted to emphasize size-fraction differences without the additional effects of coal type and pollution control device.) For... 

Detman, R., "Preliminary Estimates for Gasification of Eastern Coal", 10th Synthetic Pipeline Gas Symposium,... 

Coal with a heating value of 8,000 Btu per pound will require 50% more tons to give the same heating value as Eastern coal with a heating value of 12,000 Btu per pound. This means that we really will need 1.474 billion tons of coal by 1985 instead of 1.265 billion tons if one-third of the coal is to come from the Western states. 

Only 11 percent of the eastern coal reserves contain 0.7 percent or less sulfur. Most of this coal is low-volatile metallurgical coal, unsuitable for burning in electric power plants and, in any event, more valuable for the production of coke required for steelmaking. 

There is considerable evidence in the literature that Western coals behave differently toward liquefaction than do coals from the East or from the Interior (1). The differences can be attributed to the geological and biological history of these regions and yielded a different skeletal structure for Western coal Coal liquefaction studies have demonstrated that the direct liquefaction of Western coals is more problematic and requires more severe conditions than for Eastern coals. 

It is common practice to make a distinction between the inorganic constituents of so-called "Eastern" and "Western" coals By definition. Western coals are those for which the CaO+MgO content exceeds the Fe203 content of the ash, while the reverse is true for Eastern coals [ 1 I The inorganic constituents in Eastern coals, which are principally bituminous in rank, are predominantly in the form of discrete mineral particles. Clay minerals (kaolinite, illite) are usually dominant, followed by quartz and pyrite. The range and typical values of the mineral distribution and ash chemistry of Eastern coals are shown in Table I. These data were determined from computer-controlled scanning electron microscopy (CCSEM), Mossbauer spectroscopy, and other measurements on over a hundred coals. 

The ash samples from Wyoming coal (WYO-FA, CCWY-FA and CCWY-BA) produce a leachate that is least likely to degrade groundwater supplies. Samples from the Interior Coal Province (SI-BA, SI-FA, NEMO-FA, OK-BA and OK-FA) present the greatest potential for contamination to ground-water, particularly NEMO-FA. The EKY-FA sample from the Eastern Coal Province is intermediate between these two groups. 

The host facility was the Southwest Power Plant of the City Utilities of Springfield, Missouri. In that facility, 3.5 percent sulfur eastern coal is burned in two boilers with a total generating capacity of 200 MW. The flue gas from the electrostatic precipitators is scrubbed by two parallel 100 MW TCA s. 

Sulfur dioxide is a result of the combustion of fuels that contain sulfur, primarily coal and oil. Some coal has sulfur contents as high as 6% in the United States and 8% in China. Because of restrictions on sulfur dioxide emissions in the United States, most utilities now favor Western US coal, which is much lower in sulfur content than most Eastern coal. High concentrations of SO2 have many of the similar effects of other pollutants, including increased respiratory problems and the aggravation of cardiovascular illnesses. Electricity generation is responsible for over 60% of SO2 emissions in the United States. 

Western U.S. coals Illinois coals Appalachian coals Eastern coals... 

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