Physical structure and reactivities of cokes towards carbon dioxide

✍ Scribed by Kulai A. Kini

• Publisher: Elsevier Science
• Year: 1977
• Tongue: English
• Weight: 152 KB
• Volume: 56
• Category: Article
• ISSN: 0016-2361
• DOI: 10.1016/0016-2361(77)90019-9

✦ Synopsis

Letters to the Editor then be expressed as indicated before. Thus, a reliable estimation of the mineral and inorganic content of the coal can be quickly and routinely achieved.

The effects of the errors involved in the various ways of expressing the results of analysis can be gauged from the schematic illustration in Figure I. Expressing the results on a dry-coal basis, it is easy to see how one can achieve the 'coal substance' basis of expression, which is essential if worthwhile comparisons of coals are to be made. The 'oxygen by difference' method can only give a reliable figure if the minerals and inorganics are correctly accounted for.

Although Figure illustrates a scheme applicable only to Latrobe Valley coals, the basic idea of 'minerals' and 'inorganics' applies to all brown coals. Consequently, a suitable scheme can be developed for coals containing other minerals (e.g. gypsum [CaSOd .2H20]). The critical factors are, the knowledge,of the mineralogy, and so carrying out the chemical analysis that the concentration of inorganic elements on the coal basis can be arrived at.

In recent years, considerable research effort has been concentrated on direct hydrogenation-type conversion processes to produce oil from coal. In the case of brown coals, the oxygen content is critical with some processes as it affects hydrogen consumption.

The best possible estimate of the oxygen in coal will be necessary for the assessment of coalfields and the selection of sites for commercial coalhydrogenation plants.