Content in coal

Dry base d.a.f. base RM means reactive maurals content in coal. 

Reduction apparently creates fresh hydroaromatic structure (at the expense of the aromatics), and thus the methyl groups attached to the aromatic structures are likely to become amenable to quantitative estimation (by the Kuhn-Roth procedure), provided that the particular aromatic ring is reduced to hydroaromatic. Significantly, the reduced samples of the lower rank coals did not yield much higher values for methyl groups than the original samples. Thus, it would appear that Kuhn-Roth estimation does not completely measure the true C-methyl content in coals, especially in high rank coal samples. 

The apparent decrease in values of C-methyl content with increase in rank observed earlier (14) would now appear to be caused largely by progressive aromatization of methyl-substituted hydroaromatic structures rather than demethylation. Since the Kuhn-Roth method has limitations, an alternative method for assessing the C-methyl content in coals is desirable. 

High sulfur content in coal hinders the use of coal resources because sulfur dioxide emissions from utility and industrial boilers are a cause of acid rain. Thus, research into the nature of sulfur in coal is important for improving coal utilization. Geochemical studies of sulfur in coal provide information about the abundance, distribution, and speciation of sulfur in coal. Many of these properties are determined by geological environments and processes of coal formation. 

Alkali Benzoate/Carbonate Vaporization. Part of the alkali content in coal is organically bound and the benzoate salts,... 

The coal industry has benefited greatly through the applications of nuclear techniques. Nucleonic gauges and on-stream analysers are now regularly employed for monitoring and controlling the ash and moisture content in coal and coke. Nuclear techniques make possible the on-line determinations of sulphur and nitrogen (the causes for acid rain) in coal both of these are important for pollution control. Hundreds of millions of tonnes of coal are analysed annually by this method, a process which has become routine in the coal industry. 

An alternative depiction of the distribution of arsenic in Appalachian coal is shown in Fig. 23, which is a series of histograms of arsenic contents in coal by state. The high arsenic tails for Appalachian basin coals of Pennsylvania, Ohio, West Virginia, and Kentucky are not as prominent as those for the Warrior basin of Alabama. But it is evident that a significant number of arsenic analyses are greater than 100 ppm outside of Alabama. 

Accurate and detailed comparisons of mineral contents in coals from all U.S. coal fields will require years of coordinated work to generate the needed analytical data. To date, there are insufficient data and deficiences in the precision of the mineral data. Standardized methods of analysis are needed. Finkleman et al. (74) described the first attempt toward this goal. At this time, only rudimentary comparisons of minerals in coals from different fields can be made, preferably based on analyses made in a single laboratory, using consistent sampling and analytical methods. 

Coal to be treated = 100 tons/day, FeS2 content in coal is 22.5 kmol/day. By stoichiometric balance given in reaction scheme CS9.R1, oxygen required = 84.37 kmol/day. 

Yudovigh ye, Koeygheva AA, Obeucknikov AS and Stepanov YV (1972) Mean trace element contents in coal. Geochim Int 9 712-720. 

We believe that the abundant aromatic carbon content in coals with associated vr-electrons available in the coaly matrix is also probably effective in promoting retention and absorption of polar compounds and aromatic hydrocarbons, but also nonpolar material like alkanes are adsorbed in large proportions (cf Sandvik et al. 1991 Isaksen et al. 1998). 

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