Technological Value Of Coal Research Articles

Assessing the technological value of coal in coking

Coking coal of the same rank from different countries and fields may be distinguished in terms of use value by rating on the basis of seven technological and petrographic characteristics that determine the coke yield and properties: the ash content Ad; the total sulfur content Std; the yield of volatiles Vdaf; the plastic-layer thickness y; the vitrinite reflection coefficient Ro; the content of vitrinite-group macerals Vt; and the basicity index Bb. A range of values and a rating (on a scale from 1 to 10) are established for each of these parameters. Each rating corresponds to a particular score (from 0.1 to 1.0). Ranges of Ad, Std, Vt, and Bb are established for the whole metamorphic series, while ranges of Vdaf, y, and Ro are established for individual ranks and groups of ranks. Altogether, 105 coking coals from Ukraine, Russia, the United States, Australia, and Canada that are used at Ukrainian coke plants are investigated. The range of rating scores and their mean values are determined for individual coal ranks and groups. As an example, three bituminous coals from Ukraine, the United States, and Australia are compared by the proposed method. This method permits objective assessment of the technological value of coal within a single rank and the selection of the best purchase option.

Technological value of coal. 2. Coking coal with moderate and low yield of volatiles

The concept of technological value is analyzed. Some characteristics of technological value are refined. The coke group and lean additives are redefined in terms of the metamorphism and vitrinite content of the coal. The technological value is qualitatively assessed in terms of the ranks in those functional groups. A program is proposed for calculating the coal batch used in producing coal of specified strength.

Technological value of coal used for coking

The technological value of coal used for coking is analyzed, with particular attention to clinkering coal, the coke group, and lean additives, as well as G and GZhO coal. A relation is established between the technological value of the coal components and their permissible content in coking batch so as to produce coke of constant strength (M25 = 87%). The precision in determining the technological value of coal is assessed.

Technological value of coal and market equivalence

In practice, the technological value of coal is rarely assessed. Research indicates that actual regulatory practices in a market economy are generally ignored in publications where the technological value is assessed. The case is made that, theoretically, estimates of the technological value may be used to determine the market equivalence of coals for antimonopoly purposes.

Technological value of coal. 1. Clinkering coal

The concept of technological value is discussed. On that basis, a method of assessing the technological value of coal is recommended. The technological value of the basic clinkering coal in coking batch (Zh, GZh coal) is assessed. Similar estimates are presented for poorly coking GZhO and Zh coal, with somewhat inferior clinkering properties. Three levels of technological value are identified for clinkering coal: the first level includes Zh and GZh coal from enterprises in the Kuznets and Pechorsk basins; the second includes GZhO coal from the Raspadskaya and Vorgashorskaya mines; and the third includes G coal from the Kirov mine. GZhO and G coal from other enterprises in the Kuznets Basin does not function as clinkering coal.

Determining the technological value of coal concentrates by quantitative assessment of coke quality

A method is proposed for determining the technological value of coal concentrates on the basis of the strength, ash content, and sulfur content of the coke produced.

Determining the coking properties and technological value of coal and coal mixtures

A method is developed for determining the coking properties and technological value of coal from newly identified beds or new sections of existing mines. The coking properties are assessed on the basis of predictions of the strength and reactivity of coke obtained from batch containing coal from single beds and coal blends. The prediction of coke quality is based on the chemical and petrographic characteristics of the coal.

Determining the value of coals used for coke production

A method has been developed for determining the technological value of coal in coking, on the basis of the predicted coke strength and coke yield from batch that includes such coal. The prediction of coke strength rests on the chemical and petrographic characteristics of the coal. The value of the coal in batches may be calculated in terms of the product of the coke strength and yield and the coke characteristics for standard batch.

Technological value of coal concentrates for coking

Options are outlined for calculating the technological value of coal and coal concentrates in the context of contractual obligations and the quality of the coke produced.

Industrial-genetic value of coal

A method has been developed for determining the industrial-genetic value (IGV) of coal on the basis of the parameters that are employed in State Standard GOST 25543-88 to establish coal ranks. Comparison with the method developed by the Eastern Coal-Chemistry Institute for determining the technological value of coal in coke production shows differences in technological efficiency of the coal within and between ranks. Modification of GOST 25543-88 to include determination of both the coal rank and its industrial-genetic value is advisable.