Coal original

Oxidative Desulfurization Process. Oxidative desulfurization of finely ground coal, originally developed by The Chemical Constmction Co. (27,28), is achieved by converting the sulfur to a water-soluble form with air oxidation at 150—220°C under 1.5—10.3 MPa (220—1500 psi) pressure. More than 95% of the pyritic sulfur and up to 40% of the organic sulfur can be removed by this process. 

The various aspects of coal origins briefly reviewed above already strongly suggest that a world view of the interrelation-... 

The chemical composition of CCPs varies with coal origin and rank however, the major elemental constituents of all coal ash residues are O, Si, Al, Fe, and Ca, along with lesser amounts of Mg, S, and C. The relative abundance of constituents that typically make up more than 1 % of the total mass of fly ash and bottom ash are summarized in Table 4. These elements are found in the ash because of their lower volatility and the short time the particles actually remain in the furnace during combustion (Helmuth 1987). Both crystalline and non-crystalline compounds form on the surface of fly ash particles when elements react with oxygen in the flue gases, and through... 

Table VI shows the analysis of the coals used in the combustion studies for mercury. P-3 is a Tebo and Weir seam mixture from Henry County, Missouri while DRB-E and MR are both Pittsburgh seam coals originating in Washington County, Pennsylvania. Table VII presents the results obtained with the 100-gram-per-hour combustor, and Table VIII presents the results obtained with the 500-pound-per-hour combustor.

Product distribution data (Table V) obtained in the hydrocracking of coal, coal oil, anthracene and phenanthrene over a physically mixed NIS-H-zeolon catalyst indicated similarities and differences between the products of coal and coal oil on the one hand and anthracene and phenanthrene on the other hand. There were differences in the conversions which varied in the order coal> anthracene>phenanthrene coal oil. The yield of alkylbenzenes also varied in the order anthracene >phenanthrene>coal oil >coal under the conditions used. The alkylbenzenes and C -C hydrocarbon products from anthracene were similar to the products of phenanthrene. The most predominant component of alkylbenzenes was toluene and xylenes were produced in very small quantities. Methane was the most and butanes the least predominant components of the gaseous product. The products of coal and coal oil were also found to be similar. The most predominant components of alkylbenzenes and gaseous product were benzene and propane respectively. The data also indicated distinct differences between products of coal origin and pure aromatic hydrocarbons. The alkyl-benzene products of coal and coal oil contained more benzene and xylenes and less toluene, ethylbenzene and higher benzenes when compared to the products from anthracene and phenanthrene. The gaseous products of coal and coal oil contained more propane and butanes and less methane and ethane when compared to the products of anthracene and phenanthrene. The differences in the hydrocracked products were obviously due to the differences in the nature of reactants. Coal and coal oil contain hydroaromatic, naphthenic, heterocyclic and aliphatic structures, in addition to polynuclear aromatic structures. Hydrocracking under severe conditions yielded more BTX as shown in Table VI. The yields of BTX obtained from coal, coal oil, anthracene and phenanthrene were respectively 18.5, 25.5, 36.0, and 32.5 percent. Benzene was the most... 

Coal is a brown to black carbonaceous sedimentary rock composed of macerals (organic material) and minerals (inorganic material). Coal originated from the remnants of various forms of plant life (mosses, ferns, shrubs, trees, etc.) that flourished in swamps and bogs millions of years ago during prolonged periods of warm temperatures and abundant... 

The above results, considered collectively, are strong evidence that the ESR signals in coals originate from organic matter. To summarize (1) the g=2 coal resonance does not appear in the spectrum of low-temperature ash from the coal and (2) at least for Fe(III) and Mn(II), the ESR resonances of the mineral matter are of very low intensity in the coal spectrum and do not appear to be altered during the ashing procedure. The fact that the principal resonance appears at g=2 also supports the organic hypothesis. 

Volcanic Ash Layers in Coal Origin, Distribution, Composition, and Significance... 

Table IV also shows the per cent of the coals sulfur that remains in the ash. Preliminary results have indicated that about 70% of the sulfur remaining in the ash under these conversion conditions is in the sulfate form. This represents a considerable increase in the sulfate form since the coal originally contained only about 0.05% sulfur in this form. Although the sulfate compounds in the ash have not been identified, the Glenrock coal is known to contain considerable amounts of Ca, Mg, Fe, and Al, all of which could form sulfates.

With the working face further advance, when the falling rock gradually Enter the compaction zone, because the air leakage is reduced, the oxygen concentration is difficult to sustain the spontaneous combustion of residual coal, originally residual coal in spontaneous combustion state but... 

A sedimentary rock is formed by sedimentation at the surface of the earth and within bodies of water—sedimentation being the collective name for processes that cause minerals and organic particles (detritus) to settle and accumulate or minerals to precipitate from solution. In general terms, the debris consisted of trees, rushes, lycopods (a class of plants often loosely grouped as the ferns and club mosses), and several thousand plant species that have been identified in coal beds from their remnants (Francis, 1961 Van Krevelen, 1961). However, it does appear that none of the species identified in many different coals originated in brackish-water locales. 

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