Brown coal Australian

The Australian Permian coals vary widely in rank (maturity) and type (vitrinite content) from the Oaklands (N.S.W.) coal at 72% (dry ash-free basis) carbon, a hard brown coal (6), containing 17% vitrinite, at one extreme - through high volatile bituminous coals such as Galilee (Queensland) coal at 77% carbon, 16% vitrinite Blair Athol (Queensland) coal at 82% carbon, 28% vitrinite, Liddell (N.S.W.) coal at 82% carbon, and >70% vitrinite - to low volatile bituminous such as Peak Downs (Queensland) at 89% carbon, 71% vitrinite, and Bulli seam (N.S.W.) 89% carbon, 45% vitrinite. 

Figure 6. Dependence of maximum tar yields and corresponding total volatile matter yields during flash pyrolysis on atomic hydrogen-to-carbon ratio for some Australian and V.S.A. coals (O, 9), black coals (X), brown coals (A), Pittsburgh No. 8 (USA.) ( ), Montana lignite (USA).

The first part of this paper has shown that Australian black and brown coals differ significantly in a number of respects from coals of similar ranks from North America and elsewhere in the northern hemisphere. The rest of the paper than proceeded to indicate the progress being made to determine how the characteristics of Australian coals influence their conversion to volatile and liquid products during pyrolysis and hydrogenation. 

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. 

Two-Stage Hydrotreatment of Asphaltene in Australian Brown Coal Liquid Effects of Two-Stage Concept on Catalyst Deactivation (Changes of Catalyst Activations and Weight in the Repeated Runs")... 

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. 

The potential use of supercritical water appears especially attractive for the extraction of brown coals with their high water content, 5Q-70% for Victorian brown coals, thus removing the need for a coal-drying stage. The drying and extraction of these low rank coals would occur in a single process. The purpose of the present study was to investigate the feasibility of the extraction of Australian black and brown coals with supercritical water. The... 

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. 

The aromaticity for several samples of Northern Great Plains lignites, as measured on run-of-mine material, lies in the range of 0.61 to 0.66. A sample of Australian brown coal had an aromaticity of 0.56 a sample of Minnesota peat had an aromaticity of 0.50. Samples of vitrinite concentrates from the Northern Great Plains lignites were more aromatic, with measured values from 0.72 to 0.74. 

Financial support for this work was provided by the Victorian Brown Coal Council and the Australian Government Department of National Development and Energy under the National Energy, Research, Development and Demonstration Program. The views expressed herein are entirely those of the authors. 

Hatcher P. G., Wilson M. A., Vassallo A. M., and Lerch H. E. (1989b) Studies of angiospermous wood in Australian brown coal by nuclear magnetic resonance and analytical pyrolysis new insights into the early coalification process. Int. J. Coal Geol. 13, 99-126. 

Samples. Brown coal lithotype samples were taken from a bore core from the Flynn field in the Loy Yang region of the Latrobe Valley, Victoria, Australia. The brown coal deposits in this area are believed to be Miocene to Eocene in age. All five lithotype samples were taken at depths between 93 and 100.5 m below the surface in a 120-m core and were provided by the SECV. The black coal sample was from the Upper Hunter region (Permian) of New South Wales (Sydney Basin), Australia, and had a carbon content of 81.3%, dry, ash-free basis (DAF). This sample was provided by the Australian Coal Industry Research Laboratories Ltd. (ACIRL). The characteristics of these samples are set out in Table II. 

The authors thank the State Electricity Commission of Victoria for provision of the brown coal samples and the analytical data on them, the Australian Coal Industries Research Laboratories Ltd. for provision of the black coal sample, and the National Coal Research Advisory Council for financial assistance. We also thank J. K. Emmett for helpful discussions. 

The authors thank the Victorian Brown Coal Research and Development Committee, The National Coal Research Advisory Committee, and the Australian Research Grants Committee whose financial assistance enabled the work to be carried out. The responsibility for the views expressed rests entirely with the authors. 

The CEMS measurements were carried out in a specially designed reactor. In this reactor the samples of Fe foil were studied and treated with H /H S to obtain the iron sulfides. The detector employed for tne detection of the electrons was a He/10% CH flow counter connected in line with the reactor. The reactions of pure iron and iron sulfide with naphthoquinone were studied with this cell. The situ Mbssbauer measurements were performed using the system described in References 6 and 14. The coals used were a North Dakota lignite and an Australian Victorian Morwell Brown Coal... 

Chaffee A.L., Johns R.B. (1983) Polycyclic aromatic hydrocarbons in Australian coals. I. Angularly fused pentacyclic tri-and tetra-aromatic components ofVictorian brown coal. Geochim. Cosmochim.Acta 47, 2141—55. 

Hatcher P.G., Lerch H.E. Ill, Bates A. L.,VerheyenT.V. (1989a) Solid-state 13C nuclear magnetic resonance studies of coalified gymnosperm xylem tissue from Australian brown coals. Org. Geochem. 14, 145—55. 

Partially hydrogasified coal, upon further reaction in the high temperature second stage, gave rate constants quite similar to those obtained with Disco char (14) and residual Australian brown coal (I), both containing little volatile matter. 

Blackwood and McCarthy showed that the fixed-bed differential reaction rate of hydrogen and carbon—coconut and wood chars as well as a char of Australian brown coal—tends to zero at the graphite equilibrium. This observation may not be relevant to the over-all kinetic situation when carbon is gasified by steam in a fluidized bed, in which... 

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