High South African coal

The chapter by Eisenlohr et al. deals with the results of large scale pilot operations using a newly developed high-nickel catalyst with hot-gas recycle for temperature control. This and other work, conducted by Lurgi Mineraloeltechnik GmbH, with South African Coal and Oil Limited (SASOL), are the bases of the methanation process which Lurgi is proposing for commercial plants. 

H. Roberts (South African Coal, Oil, and Gas Corp.) May I say that for the pilot plant we used a reciprocating compressor which would operate only at near ambient temperature. So we simulated the operation of the hot recycle compressor by adding high pressure steam on the delivery side of the reciprocating compressor. We did not use a hot recycle compressor in the pilot plant. 

South African coals differ from most Northern Hemisphere coals in their geological age, unusual petrology and their high mineral matter content. If these coals are to be used for conversion to synthetic fuels then criteria must be found to enable predictions of their behaviour under liquefaction conditions to be determined. This paper describes the hydrogenation of a number of South African coals using two different techniques, to ascertain whether well known coal properties can be used to predict their hydrogenation behaviour. 

The different slopes for the lines of best fit for total reactives and vitrinite + exinite reflects the special petrology of the majority of South African coals used in this study (see Table III). For these coals the reactives contain a high proportion of semi-fusinite in the inertinite. 

The results obtained from the float/sink fractions are shown in Figure 11. It could be that the increase in oil yield obtained with the higher mineral matter fractions is due to the increase in sulfur content that varies from 0.5 per cent in the 1.4 float to 9 per cent in the 1.65 sink fraction. The significance of these results, at least as far as South African coals are concerned, is that a high mineral matter content does not necessarily mean poor performance during coal liquefaction. 

This unit was then used for testing conversion of South African coal [49] and petroleum coke [23] using natural ilmenite ores. The low cost of natural ores, such as ilmenite, makes these materials particularly well-suited for solid fuel looping processes, that is, for use in an envirraiment with a high risk of deactivation and carrier loss due to... 

HP high pressure, IGCC integrated gasification combined cycle, IP intermediate pressure, LHV lower heating ue, Pitt 8 Pittsburgh No. 8 coal, SAf South African coal. 

Figure 8.3 Exergetic overview of all cases investigated (HTW - high-temperature Winkler, INCI -internal circulation gasifier, Pitt 8 - Pittsburgh No. 8 coal, SAf- South African coal) (with permission from Ref. [9]. Copyright 2014, Elsevier).

Figure 9.5 Reh diagram with gasifier opera- e-line - entrainment line, f-line - fluidization tion points for South African coal (30 bar) and line, FBDB - fixed-bed dry bottom, HTW -varied ash content for the internal circulation high-temperature Winkler), gasifier (INCI) concept (BGL - British Gas/Lurgi,...

The South Africans have applied the Fischer-Tropsch technology in their SASOL facility. The Sasol (South African Coal, Oil and Gas Corporation) installation is the world s largest synfuel plant based on coal. It converts an inferior high-ash (35%) coal into a broad spectrum of products, which may include ethylene, propylene, butylene, gasoline, and long straight-chain alcohols and hydrocarbons. The Sasol plant has been operating for over 35 years. 

Table I shows that most of the South African bituminous coal contain high quantities of mineral matter which is often intimately associated with the organic matter of the coal. About half of the resources yield between 30 and 35 per cent ash.

Table 5.10 presents the information about the selected standard and high-ash coals. The values for the standard Pittsburgh No. 8 (Pitt 8) coal are talcen from literature [57], whereas the analysis of the high-ash South African (SAf) coal was obtained in laboratory at the Institute of Energy Process Engineering and... 

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