Pearson Coal Petrography

Fingerprinting your coals, cokes, and carbons

Fingerprint Library

 

This on-line Fingerprint Library allows you to explore and understand the principal petrographic differences among world coking coals. Each coal is unique – and so is its’ Fingerprint.

For over a decade, we have recorded Fingerprints – Reflectance Profiles – of coals from all over the world, but because most of them are not our property and are protected by client-confidentiality, we cannot use them. Instead we have prepared a collection of modeled coals that are virtually identical to the coal Fingerprints of the naturally-occurring coking coals.

To illustrate Fingerprint variation, and how this impacts quality of metallurgical cokes, we have chosen the ASTM coke-strength Stability Index, or Coke Strength prediction, as the base graph (Figure 1). Other parameters could equally have been used – for example the prediction of Plastic Layer Thickness, measured in the Sapozhnikov test, and featured in Chinese & Russian coal classifications! The graph is shown below in terms of coal Rank and coal Type. Move the mouse over the graph, and a corresponding mathematically-modelled coal Fingerprint for that particular Maximum Vitrinite Reflectance & Total Inert content is displayed, in the transposed terms – Random reflectance & Vitrinite percent – the parameters of the ISO Coal Classification. The unique five digit identifier code is derived from the percent Vitrinite, and Random reflectance (x100), for the coal shown in the profile.

These diagrams illustrate that Provincialism plays a big part in dictating the quality of a coal (Fig. 2, below). For example, coal 50123, from Australia, and 67142, from Canada, both have the same Volatile Matter content of about 23% DAF, yet their Romax and Vitrinite content are quite different. Because VM is not an independent variable, alone, it is a relatively insensitive measure of Rank , so care must be taken when comparing coals, especially from different parts of the world, as in the ASTM Classification of Coal by Rank.

The Library is best viewed at 1024×768 resolution, but if you are running a greater resolution, you may wish to resize your browser so that the Fingerprint graph does not overlay the Coke Strength graph

Coal 50, 142 Coal 55, 142 Coal 60, 142 Coal 65, 142 Coal Smokey River Coal 75, 1.42 Coal Itmann Coal 85, 1.42 Coal 90, 1.42 Coal 95, 1.42 Coal 100, 1.42

Coal 50, 1.32 Coal 55, 1.32 Coal 60, 1.32 Coal Balmer Coal 70, 1.32 Coal Saraji Coal Peakdowns Coal 85, 1.32 Coal 90, 1.32 Coal 95, 1.32 Coal 100, 1.32

Coal 50, 1.23 Coal 55, 1.23 Coal 60, 1.23 Coal Bulli Coal 70, 1.23 Coal 75, 1.23 Coal 80, 1.23 Coal 85, 1.23 Coal 90, 1.23 Coal 95, 1.23 Coal 100, 1.23

Coal 50, 113 Coal 55, 113 Coal 60, 113 Coal 65, 113 Coal 70, 113 Coal 75, 113 Coal 80, 113 Coal 85, 113 Coal Rowland Coal Caribbean Coal 100, 113

Coal 50, 104 Coal 55, 104 Coal Wollondilly Coal 65, 104 Coal Moura Coal Goonyella Coal Sewell Coal Harman Coal 90, 104 Coal 95, 104 Coal 100, 104

Coal 50, 094 Coal 55, 094 Coal Blackwater Coal 65, 094 Coal 70, 094 Coal 75, 094 Coal 80, 094 Coal 85, 094 Coal 90, 094 Coal 95, 094 Coal 100, 094

Coal 50, 085 Coal 55, 085 Coal 60, 085 Coal Witbank Coal 70, 085 Coal 75, 085 Coal 80, 085 Coal 85, 085 Coal 90, 085 Coal 95, 085 Coal 100, 085

Coal 50, 075 Coal 55, 075 Coal 60, 075 Coal 65, 075 Coal 70, 075 Coal 75, 075 Coal 80, 075 Coal 85, 075 Coal 90, 075 Coal 95, 075 Coal 100, 075

Coalid 99

Coalid

Figure 1. Coke Strength Graph – Romax Reflectance(%) Vs Total Inerts (%).

Figure 2. Provenance of Coals

Figure 2. Provenance of Coals, from (Pearson, 1980).