United bituminous coals from

The present paper presents batch autoclave data on the direct hydrocracking of a single sub-bituminous coal from the Powder River basin of southeastern Montana. Comparative data were also obtained with the Pittsburgh Seam bituminous coal that was used in the previous work (I). Data on the regeneration of simulated spent melts from such an operation are also given in a continuous bench-scale, fluidized-bed combustion unit. 

It is generally appreciated that the mineral matter associated with some coals may act as a catalyst for liquefaction. A common observation is that among bituminous coals from the eastern United States, those with a relatively high mineral matter content also provide relatively high liquefaction yields. Also, addition of coal-derived mineral matter increases the liquefaction yields from those coals with low mineral matter content. The involvement of pyrite in these effects has been fairly well established. The importance of clay and/or other minerals is less well defined. 

Coals of the Western United States tend to have lower heating values, lower sulfur contents, and higher moisture contents relative to bituminous coals from the Eastern United States. The efficiency loss associated with high-moisture- and ash-content coals is more significant for slurry-feed gasifiers. Consequently, dry-feed gasifiers, such as the Shell gasifier, may be more appropriate for low-quality coals. 

Properties. Pilot-unit data indicate the EDS process may accommodate a wide variety of coal types. Overall process yields from bituminous, subbituminous, and lignite coals, which include Hquids from both Hquefaction and Flexicoking, are shown in Figure 14. The Hquids produced have higher nitrogen contents than are found in similar petroleum fractions. Sulfur contents reflect the sulfur levels of the starting coals ca 4.0 wt % sulfur in the dry bituminous coal 0.5 wt % in the subbituminous and 1.2 wt % sulfur in the dry lignite. 

Table 12 gives the estimated destinations for United States bituminous coal exports in 1976 and 1989. The volume of exports almost doubled during this period. About one-third of the bituminous coal exported from the United States in 1976 went to Europe, another third to Asia, and the remainder to North and South America. The pattern shifted to about 24% to North and South America, about 50% to Europe, 24% to Asia, and the balance to Africa ( ) ... 

Naphthalene is produced from coal tar or petroleum. It is made from petroleum by dealkylation of methylnaphthalenes in the presence of hydrogen at high temperature and pressure. Petroleum was a major source of naphthalene until the 1980s, but now most naphthalene is produced from coal tar. The pyrolysis of bituminous coal produces coke and coke oven gases. Naphthalene is condensed by cooling the coke gas and then separated from the gas. Naphthalene production in the United States is slightly greater than 100,000 tons annually. 

Samples Preparation. The coal liquids were derived from the catalytic liquefaction of Pittsburgh Seam bituminous and Wyoming sub-bituminous coals. The analysis of these coals is given in Table I. The coals were liquefied in a bench-scale catalytic unit using cyclone overhead product as recycle solvent to insure that the liquid products were derived from the coal and not the solvent. The product streams from... 

The above work concentrated most of its attention on the use of zinc chloride as the molten halide and on the use of bituminous coal extract as feed to the process. Hydrocracking of the extract (1) and regeneration by a fluidized-bed combustion technique of the spent catalyst melt (2) from the process were both demonstrated in continuous bench-scale units. 

A substantial program was also previously conducted in a batch autoclave unit on the direct hydrocracking of bituminous coal (1) with zinc chloride melts, but no work was done in either batch or continuous units on regeneration of spent melts from direct hydrocracking of coal. 

Seven fuels were burned in these initial tests two petroleum fuels, one regular sulfur fuel oil (RSFO) and a low sulfur fuel oil (LSFO), and five EDS fuel oils. The EDS fuel oils were blended from components produced in the one ton per day pilot unit at the Exxon Research and Engineering site in Baytown, Texas. Products from the liquefaction of two coals, a bituminous Illinois coal from the Monterey No. 6 mine, and a sub-bituminous Wyoming coal from the Wyodak mine, were tested. Fuel oil blends were made with products from each of the coals, with and without coker liquids, to produce four of the EDS fuels. The fuel oil derived from Illinois coal containing coker liquids was blended... 

The aim of the present work is to study the effects of extraction temperature, solvent density and addition of cosolvents on the conversion and liquid yield and also on the characteristics of the extracts and residues obtained from SCFE of a high-ash (29.1%) Brazilian mineral coal. For this purpose a Butia coal, sub-bituminous coal, was employed under different experimental conditions in a semi-batch laboratory-scale unit using toluene as primary solvent, over the range of 593-673 K in temperature and 4.7-11.5 MPa in pressure. 

Figure 5.15. Proven reserves of bituminous coal (unit Wy/m i.e., for each cotmtry, the average number of years for which an energy flow of 1 W per m of land surface could be derived at 100% energy extraction efficiency) (based upon data from World Energy Council, 1995 with area-based layout from Sorensen, 1999).

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