Bituminous coal with density

Physical Properties. Physical properties of waste as fuels are defined in accordance with the specific materials under consideration. The greatest degree of definition exists for wood and related biofuels. The least degree of definition exists for MSW, related RDF products, and the broad array of ha2ardous wastes. Table 3 compares the physical property data of some representative combustible wastes with the traditional fossil fuel bituminous coal. The soHd organic wastes typically have specific gravities or bulk densities much lower than those associated with coal and lignite. 

In many ways, the molecular models that we have used as the basis for our CAMD studies describe coal structure very well. However, none of the models investigated thus far contains explicit three-dimensional covalent cross-links. Actualfy, the models we have studied are primarily constructed of long chains of one-dimensionally-linked clusters with a number of short side-chains. However, it has been established on the basis of solvent swelling studies (11.15.16) that bituminous coal is primarily made up from a three-dimensional network of clusters held together by covalent bonds and by an even higher density of hydrogen bonds. These macromolecular models of coal, which are less concerned with the molecular structure than with the ways that clusters are bonded to one another, provide a complementary way of describing coal structure. 

In Chap 19 of Ref 63, pp285—98, is described the development of "Bituminous Coal Mines , with recommended expls for blasting rock faces DuPont Gelobel AA , while "Monobel AA or even lower density AN... 

Successfully applying the method used by Fenton to prepare his concentrates depends upon two factors. First, there must be adequate density differences between the macerals in the sample, and second, there must be an initially high concentration of the required maceral. In attempting to separate either resinite or cutinite from sporinite of the same coal, neither of these conditions can be fulfilled, at least when the coal is of bituminous rank or higher. If, however, samples on a semi microscale are acceptable, it is possible to prepare concentrates of resinites of satisfactory purity from bituminous coals by simple mechanical means. The method has been described by Murchison and Jones (17) and mainly involves picking with fine probes on differently prepared surfaces of coal under a stereoscopic microscope. Resinites from lignites pose less of a problem because their occurrence in fairly substantial lumps is quite common these and fossil resins such as kauri gum and amber usually can be prepared to a purity of almost 100% with ease. 

Coke (Coke in Fr or ftal Cok or coque in Span Koks in Ger or Rus). Coke is the solid residue which remains when certain types of bituminous coals are heated in retorts or special ovens (such as "behive type) to high temps out of contact with air until practically all of the volatile constituents are removed. Coke consists principally of C and of small amts of S, H, N, O mineral matter present in the original coal. It is a hard, cellular form, porous substance, ranging in color from silvery gray to dull black. Its true density 1.85 -1.90, is higher than that of coal, but its bulk d is lower because of porosity... 

Thus, it is not surprising that coal density is variable and dependent on the coal type. For example, the density of anthracite is on the order of 1.55, whereas bituminous coal has a density on the order of 1.35, and lignite has a density on the order of 1.25. However, such generalizations are to be treated with caution since coal density is usually determined by displacement of a fluid, but because of the porous nature of coal and also because of physicochemical interactions, the density data observed vary with the particular fluids employed, and different fluids may have to be employed for different coal types (Agrawal, 1959 Mahajan and Walker, 1978). 

Product characterization from liquefaction has not been extensive. Phi 1p and Russell (95) have examined products by Py-GCMS from metal halide catalyzed hydrogenation of a vitrinite, alginite, and inertinite, each from a different source. They were able to correlate Py-GCMS results with reaction temperature. King, et al. (96) examined the short contact time liquefaction of macerals separated by DGC from a single hvB bituminous coal. They found correlations between density and reactivity and composition of the products. 

Figure 6. Variation of atomic ratios with density for several high volatile bituminous coals (a) H/C ratio (b) 0/C ratio.

Samples. Two of the coals used 1n this study were obtained from the Penn State Coal Sample Bank, an HVA bituminous coal (PSOC 1103) from the Upper Elkhorn 3 seam in Eastern Kentucky and an HVA bituminous coal (PSOC 828) from the Brazil Block seam in Indiana. A third coal from which vitrinite and fusinite were hand picked was an Illinois No. 2 seam HVC bituminous coal from Northern Illinois. Also, resinite and vitrinite samples were hand picked from a Hiawatha seam bituminous coal from the King 6 mine in Utah. Finally, the alginite sample was obtained from an Ohio No. 5 seam (PSOC-297) coal by 06C (2,5). All of the elemental and petrographic analyses are presented in Table I. The details of the sink-float technique have been reported previously (1). Typically, a 3 micron particle size demineralized coal Ts centrifuged in aqueous CsCl2 solution of the appropriate density with a small amount of surfactant added to disperse the coal particles. The exinites in the float are... 

The same researchers further test copper powder in differential scanning calorimetry (DSC-MS) with sub-bituminous coal, wood, and low-density polyethylene as fuel and report that copper is completely reduced in the process and no carbon deposits were observed [33]. In a separate study [34], Cu- and Ni-based carriers were... 

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