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—A method of determining the packing density of coal concentrates in open storage is proposed and tested at AO Ural Steel. The variation in packing density over the height and length of the coal stack is determined. A protocol is developed for determining the packing density of coal concentrates in open storage.

—The properties of tar from the high-temperature coking of volatile-rich petroleum coke (CA, coking additive) are compared with the properties of coal tar. According to thermogravimetric data for the residue at temperatures beyond 360°C, the content of high-boiling components is considerably higher for petroleum tar than for coal tar. However, its yield of coke residue is lower than for coal tar. The petroleum tar contains polyaromatic hydrocarbons and heterocyclic sulfur-containing compounds, both of which are also found in coal tar. However, much larger quantities of sulfur-containing quantities are seen in petroleum tar, while the content of individual polyaromatic hydrocarbons is much lower.

Laboratory coking of experimental batch simulating the industrial batch at OAO Altai-Koks provides the basis for a model predicting the quality (CSR, CRI) of laboratory coke on the basis of the coking indices $$C{{I}^{{{{V}_{{\text{o}}}}}}}$$ and CI. The relation derived between the quality (CSR, CRI) of the laboratory coke and the quality (CSR, CRI) of industrial coke produced by wet and dry quenching permits prediction of CSR,CRI for the industrial coke on the basis of predicted or experimental CSR and CRI values for the laboratory coke. This approach permits ongoing determination of the CSR and CRI values of industrial coke produced with wet and dry quenching in the following circumstances: (i) in correcting production batch on the basis of the coal components available in the store and other nearby coal resources; (ii) in correcting production batch by means of outside concentrates not currently available at the plant; (iii)in analysis of the reasons for quality changes of the coke at any moment; (iv) in developing promising batches as the market for coking coal changes.

The properties of coking batch may be stabilized by means of DK coking additive based on the products of petroleum pyrolysis, characterized by low ash content (Ad = 0.4%), high sulfur content (Std= 4.1%), and high yield of volatiles (Vdaf = 17.2%) relative to coal concentrates. Individual coking of DK coking additive yields a product (particle size >40 mm) with postreactive strength CSR = 77–79%, reactivity CRI = 18–22%, and density 1200–1400 kg/m3. Differential scanning calorimetry of experimental coke samples reveals six stages in their heat treatment in air: preliminary heating, intense oxidation, gasification of carbon, surface combustion of the gaseous products, their flare combustion, and oxidation of the residue. The use of DK coking additive in the coking batch shifts the oxidation process to higher temperatures and ensures the largest interval of heat liberation at elevated heating rate, with up to 50% DK additive. With increase in the content of DK additive from 30 to 50%, the activation energy is increased by 4.56 kJ/mol for each additional 10%. In that case, the supply of atmospheric oxygen to the combustion zone must be improved

The introduction of DK coking additive to the coal batch improves the metallurgical properties of the coke produced. The quality of coke produced exclusively from DK additive permits its effective use. When introduced in the axial zone of the charge hole, it forms an axial ventilation region and thus the hearth may be packed with coke that is not susceptible to wetting by slag melt.

Analysis of the chemical composition of solid fuel permits the identification of the optimal proportions of its components for effective heat generation. Kinetic analysis of the oxidation of the carbon in the coke, by means of the complete curve obtained in differential scanning calorimetry with continuous heating, reveals six basic periods: drying and heating; oxidation of the carbon in the coke; endothermal gasification; surface oxidation of the gaseous products; flame combustion of the gaseous products, and oxidation of interior layers of the fuel. By assessing the behavior of the coke in shaft furnaces, the requirements on its granulometric composition, density, and mechanical strength in transportation and heat treatment may be determined. Recommendations are made regarding the characteristics of coke for use in the basic forms of cupola furnaces.

The influence of DK coking additive from oil refining—specifically, the solid product from the slow coking of heavy petroleum residues—in coal batch on the quality of the coke produced is studied in laboratory conditions. In comparison with coal concentrates, DK coking additive is characterized by lower ash content (Ad = 1.1%) and higher sulfur content (Std= 3.7%); the yield of volatiles Vdaf = 18.2%. The DK coking additive is added to the batch in doses of 4.8%, 9.1%, and 13%, with proportional decrease in the batch components. In other cases, DK coking additive is added to the batch in doses of 10%, in place of coal of the clinkering and coke groups. Coke is produced from the batch in the laboratory. The coal charge is 2 kg; the piece size is ≤3 mm. With increase in the content of DK coking additive to 13%, the strength of the coke after reaction (CSR) increases linearly from 49.2 to 54.9%, while the reactivity CRI declines linearly from 37.9 to 33.8%. The improvement in coke quality is greatest when GZh coal (a clinkering component) is replaced by the DK additive: CSR rises to 59.2% and CRI falls to 30.8%. The most promising approach is to replace the scarcest and most expensive coal—OS coal (the coke group) and KS coal (the lean group)—with DK additive, with 3.8% increase in CSR and 3.3% decrease in CRI.