Australian coal

S. African coals Australian coals Indian (Assam) coals Indian fly ash... 

The conversion was highest for coals in a narrow Ro max range of between 0.65 - 0.70. Cudmore s data on Australian coals also appears to exhibit a maximum when reflectance data is plotted against conversion (8). It is difficult to interpret this data because of the large variation in the vitrinite and reactive semi-fusinite content of these coals. The reactivity of vitrinite and reactive semi-fusinite would be expected to vary with rank but to different degrees. For several of the lower rank coals vitrinite is only a minor component of the coal. 

For American and European coking coals the behaviour of semi-fusinite is generally less important since only small quantities of this maceral are usually present. However, South African coal used in coke oven-blends contains as little as 40 per cent vitrinite and as much as 45 per cent reactive semi-fusinite (12). The partial reactivity of the semi-fusinite fraction during liquefaction of Australian coals has been reported by Guyot et al (13). They found that the low reflecting inertinite in two coals up to (a reflectance from 1.40 to 1.49) was reactive. This agrees with the results of Smith and Steyn (12) who consider that the semi-fusinite fraction in South African coals up to V- 5 (1.50 - 1.59) can be reactive to coking. 

Cudmore, J.F. Coal Borehole Evaluation Symposium, Australian Institute of Mining and Metallurgy, 1977, Oct., 146. 

Guyot, R.E., Diessel, C.F.K. Australian Coal Industry Research Laboratories, Published Report 79-3, 1978, Dec. 

The Characteristics of Australian Coals and Their Implications in Coal Liquefaction... 

Location, Geology and General Characteristics of Australian Coals... 

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. 

The wide variation in Australian coals in rank, type and inorganic impurities and the significant differences between these... 

It is possible to produce some liquid hydrocarbons from most coals during conversion (pyrolysis and hydrogenation/ catalytic and via solvent refining)/ but the yield and hydrogen consumption required to achieve this yield can vary widely from coal to coal. The weight of data in the literature indicate that the liquid hydrocarbons are derived from the so-called reactive maceralS/ i.e. the vitrinites and exinites present (7 8 1 9). Thusf for coals of the same rank the yield of liquids during conversion would be expected to vary with the vitrinite plus exinite contents. This leads to the general question of effect of rank on the response of a vitrinite and on the yield of liquid products and/ in the context of Australian bituminous coals, where semi-fusinite is usually abundant/ of the role of this maceral in conversion. 

Experimental data published recently by Cudmore (10) for eight Australian bituminous coals, reproduced in Fig. 2, show a direct linear correlation between conversion (to gas + liquids), under non-catalytic hydrogenation conditions using Tetralin as... 

The steep dependence on hydrogen content of the tar yields obtained during the low temperature (500°C) fluidized bed carbonization of 14 Australian coals, ranging in rank from 72% to -89% (dry ash-free basis) carbon content, is clearly demonstrated in Fig. 5 (15,16). 

Figure 4. Dependence of tar yield, determined by low-temperature Gray-King carbonization assay, n atomic hydrogen-to-carbon ratio for a wide range of Australian coals. Tar yield = 50.4 X H/C — 25.9 correlation coefficient, 0.95.

Figure 5. Dependence of tar yields from low-temperature (500°C), fluidized-bed carbonization of hydrogen content for some Australian coals (15, 16)...

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).

Figure 7. Dependence of yields of hydrogenation products on the atomic hydro-gen-to-carbon ratio (a) Australian coals—noncatalytic conditions (10) (b) Canadian coals—catalytic conditions.

A project initiated by the author when with CSIRO has, as one of the objectives, the study of effect of the mineral matter in selected Australian coals during catalytic hydrogenation (13). 

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. 

The results presented and discussed here for current investigations on Australian black coals indicate strongly that,... 

The author gratefully acknowledges the co-operation and help he has received from the Australian Coal Industry Laboratories (ACIRL), the Melbourne Research Laboratories of the Broken Hill Proprietary Co. Ltd. (MRL/BHP), the Commonwealth Scientific and Industrial Research Organization (CSIRO), in providing information and data, often unpublished, to assist in the preparation of this paper. In particular, he wishes to thank Dr. N. White (MRL/BHP), Mr. J. Cudmore (ACIRL), and the following former colleagues in CSIRO - Prof. A.V Bradshaw, Dr. D. Jones, Mr. H. Rottendorf,... 

Taylor, G.H. and Shibaoka, M., "The Rational Use of Australia s Coal Resources", Paper 8, Institute of Fuel (Australian Membership) Conference on "Energy Management", Sydney, Aust., November 1976. 

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.) ... 

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