Brown coal parameters

In this study, we have tried to find a more comprehensive parameter related to coal reactivity, as represented hy conversion, hy liquefying several ranks of coals. These cover a wide range from lignite to bituminous coal. Also we have studied the difference of coal reactivity caused hy the mining sites in Australian brown coal mines. Selected coals from a wide range of rank are located in the coal hand shown in Fig.2. The resulting parameters are compared with other parameters reported hy other researchers (2, 3.) ... 

As stated before, volatile carbon % is considered to be one of the most important parameters of hydroliquefaction. Also a fairly good linear relationship between the volatile carbon % in coal and low temperature tar yield from coal is found in Morwell brown coals, based on the data from the State Electricity Commission of Victoria (SECV) in Australia, as shown in Fig.9 Therefore, the low temperature tar yield is also estimated to be an important parameter. In addition, the color tone of brown coal (lithotypes) is shown in this figure. From this figure, it is observed that both volatile carbon % and low temperature tar yield are in a fairly good relation to the color tone of brown coal. Thus, as proposed by the Australian researchers, the color tone of brown coal is considered to be an important parameter. 

In the case of Australian brown coal, the parameter related to the color tone of coal proposed by the Australian researchers. 

Francioso, O., Ciavatta, C., Montecchio, D., Tugnoli, V., Sanchez-Cortes, S., and Gessa, C. (2003). Quantitative estimation of peat, brown coal and lignite humic acids using chemical parameters, 1H-NMR and DTA analyses. Bioresour. Technol. 88(3), 189-195. 

It is important to realize that the bed moisture content of soft brown coals is significantly higher than the equilibrium moisture holding capacity, a parameter which is used to characterize higher rank coals. This is illustrated in Table 1 for a range of Victorian brown coals. 

The correlations between the chemical brown coal data, petrographical parameters and the refining behaviour are described in the following discussion. 

A correlation analysis of the chemo-physical parameters of Rhenish brown coal and its briquettability gives only trend data as well. Therefore generally an anticipated quality assessment of the briquettes is restricted to the following points ... 

Victorian brown coal occurs in five major lithotypes distinguishable by color index and petrography. Advantage has been taken of a rare 100 m continuous core to compare and contrast chemical variations occurring as a function of lithotype classification. For many parameters there is a much greater contrast between the different lithotypes than there is across the depth profile of (nearly) identical lithotypes. Molecular parameters, such as the distributions of hydrocarbons, fatty acids, triterpenoids and pertrifluoroacetic acid oxidation products, together with gross structural parameters derived from IR and C-NMR spectroscopic data, Rock-Eval and elemental analyses and the yields of specific extractable fractions are compared. 

Chemical composition of waste plastic cracking products depends on shares of the individual polymers (PE, PP, PS) in the feed and process parameters. This fact decides the technological application of the final products. Important products of the cracking process, both petroleum fractions and waste plastics, are coke residues. Coke residue yield increases considerably, up to 10 wt%, in cracking of municipal and industrial waste plastics since they contain various inorganic impurities and additives. It can be applied as solid fuel, like brown coal. In the fluid cracking the solid residue is continuously removed from the process by combustion in a regenerator section. 

The example of application of the statistical prediction method represented in Figure 4 contains a Czechoslovakian brown coal of group 1 which experience has shown to be a particularly vicious fouling coal and a GDR brown coal of group 3 which tends toward behavior of a salt coal but whose operational behavior, while complicated, can be controlled. The values calculated for fg and fp coincide with practical experience while the parameter Rg indicates that the Czechoslovakian coal is harmless whereas the GDR coal is characterized as uncontrollable by available technologies. 

The ash analyses and estimated parameter shown in Table 1 refer to brown coals from the GDR, Hungary, Poland,... 

Classification of Brown Coal by the International System Group Parameter Tar... 

Table 3.5 shows typical samples according to the ASTM classification mosdy displaying American coals. A typical Indian high-ash mediiun volatile bituminous coal as well as a German brown coal (lignite B) are added for comparison. Again the dilemma of coal classification becomes evident, as none of the analyzed parameters changes steadily with rank alteration. 

The results available so far have shown that the removal of both NO and SO2 by means of brown coal coke largely depends on the moisture contained in the flue gas. That is why further tests will be directed to the influence of this parameter. In addition, other parameters will be investigated which may have an influence on the removal of SO2 and NO,. 

Thus we have conducted work on the structural parameters of coal hydrogenation products using the method of Brown-Ladner (1), and from the results obtained we have developed correlations of the reaction. Based on the above, the outline of the reaction mechanisms have been previously discussed and our results have been reported (2, 3J. ... 

Table V shows yields and structural parameters of SP-300 fractions. These fractions were black solid materials like the feed coal, as compared to dark-brown viscous liquids of the HVL-P fractions. The overall average molecular weight of SP-300 was more than three times that of HVL-P. SP-300 fractions have much larger R, RN and //cl than HVL-P fractions. The //cl values disclosed that there were, on the average, 2.8 aromatic clusters per molecule in SP-300, as compared to 1.1 aromatic clusters per molecule in HVL-P. Thus SP-300 fractions are high molecular weight materials,in which the degree of depolymerization is relatively low. This in turn suggests that SP-300 has retained more of the original structures of the parent coal than has HVL-P.

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