Том 59, № 8 (2016)

The reactions of coal with the materials used in determining the ignition temperature of unoxidized coal according to Ukrainian State Standard DSTU 7611:2014 are analyzed. First, the ignition temperature of various types of coal from Ukraine, Russia, Canada, Australia, the Czech Republic, Poland, and Indonesia is determined. The influence of the composition, structure, and properties of the coal on its ignition temperature is assessed. The ignition temperature of the unoxidized coal is found to be closely related to the content of organic carbon C^daf and aromatic carbon C_ar, the structural parameter δ characterizing the degree of saturation of the coal’s organic mass, and also the vitrinite reflection coefficient R_o and the yield of volatiles V^daf.

The utilization of solid domestic waste—plastic, rubber, leather, textiles, wood, and paper—in coking batch after mixing with residues from coal-tar stores at coke plants is investigated. All the solid domestic waste considered—especially plastic waste—increase the yield of coke in the >80 and >60 mm class and the yield of tar and benzene. The introduction of plastics and a mixture of solid domestic waste with up to 1% of tar-storage residues does not impair the quality of the coke produced.

The heat treatment of the anthracene fraction of coal tar under pressure is investigated. In the production of synthetic pitch, the temperature is varied in the range 400–480°C. The duration of the process is 5 h, and the pressure is 3–5 MPa. After treatment at temperatures below 480°C, the pitch produced lacks the quinoline-insoluble fraction. Chemical analysis shows that increasing the treatment temperature results in consumption of cata-condensed aromatic hydrocarbons, with simultaneous accumulation of peri-condensed aromatic hydrocarbons. NMR and IR spectroscopy indicates simultaneous increase in the aromatic index and the degree of condensation of samples with increase in the treatment temperature, as the result of dealkylation and condensation. Optical analysis shows clearly expressed mesogenic properties of the synthetic pitch. Pitch produced by low-temperature synthesis forms needle coke, with a greater anisotropy and greater real density than coke obtained from pitch produced by high-temperature synthesis. With increase in pressure in the course of coking, the anisotropy and the real density decline for low-temperature pitch, but increase for high-temperature pitch.

If anthracene oil is used to produce extracts from 2B, D, 2G, GZh coal, coal pitch may be produced by oxidation of the extracts using atmospheric oxygen. The resulting pitch is characterized by higher yield and by a greater coke residue than is observed in pitch produced from anthracene oil without added coal in analogous conditions. Ultrasound treatment for 3 h on an IL10-0.63 unit ensures complete solution of the coal (4–9%) in the anthracene oil. The mineral component of the coal also enters the solution and is then concentrated in the pitch formed. To reduce the ash content of the pitch, ash must preliminarily be removed from the initial coal. For the example of 2B and D coal, it is found that reducing the ash content of the coal to ~1% and subsequent solution in the anthracene oil to a coal concentration of 5–8% yields a coal extract such that pitch with no more than 0.4% ash and up to 41% coke residue is formed on oxidation by atmospheric oxygen.