Brown coal liquefaction

Brown Coal Liquefaction process, 6 849 Brown cyclization product, 21 147 Brownian diffusion, 13 151, 152 Brownian diffusion, in depth filtration theory, 11 339... 

Chemical separation of the catalyst from the bottom products. Some coals, such as Australian brown coal, consist principally of reactive macerals and contain organically bound calcium and sodium, which almost exclusively produce carbonate and chloride minerals during liquefaction. The catalyst can be separated by extracting these minerals, which exist on the catalyst surface or as precipitates in the bottoms product. 

This study indicates that extraction with supercritical water could be an attractive route for liquefaction of Victorian brown coals (but probably not black Australian coals). The low cost and ready availability of the solvent (water), the relatively high H/C atomic ratios of the extracts, and also as no hydrogen or coal-drying are required, are positive factors. Higher yields can be obtained when a strong base or a hydrogen-donor is added to the water. 

R. Hamilton provided expert professional councel during the development of the Figures. F. Brown, B. D. Blaustein and G. A. Gibbon were consistently supportive throughout the development of this approach. S. S. Pollack, E. Hlig and D. Cillo supplied helpful suggestions and technical insights into coal liquefaction procedures. 

As a result of the Brown Coal Evaluation Program, the understanding of the variability of Victorian brown coals and its implications for utilization have improved substantially. It has become apparent that certain chemical properties can have important consequences for utilization of the coal for power generation, liquefaction and other applications. 

Lett, R. G., J. W. Adkins, R. R. DeSantis and F. R. Brown, Trace and Minor Element Analysis of Coal Liquefaction Products", PETC/TR-79/3, August, 1979. 

Fig. 14. Preferred liquefaction-coking liquid yields in the EDS process for various coals where Hi represents Flexicoking liquids and , liquefaction liquids (124). A, Ireland (West Virginia) B, Monterey (Illinois) C, Burning Star (Illinois) D, Wyodak (Wyoming) and E, Big Brown (Texas).

Brown, R., and Witter, A. (1979). Health and Environmental Effects of Coal Gasification and Liquefaction Technologies, DOE/HEW/EPA-03. Department of Energy, Department of Health, Education and Welfare, U.S. Environ. Prot. Agency, Washington, D.C. 

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