Vol 61, No 4 (2018)

By statistical analysis of research data for coal samples, coal blends, and coal batches used in Russia and Kazakhstan, relations between the vitrinite reflection coefficient and the fuel ratio are established, with good agreement between the calculated and actual vitrinite reflection coefficients. Statistical analysis of a representative database for coal samples, coal blends, and coal batches from Ukraine, Poland, the United States, Canada, and Australia, based on research in those countries, permits the formulation of very close correlations between the vitrinite reflection coefficient and the fuel ratio F_r, with excellent agreement between the calculated and actual vitrinite reflection coefficients.

Low-temperature pyrolysis of slightly metamorphosed D, DG, and G coal in a Fisher retort produces semicoke, whose specific surface, total pore volume, micropore volume, and mesopore volume are determined. The porous structure of the semicoke is investigated at the 77 K isotherm corresponding to nitrogen sorption and desorption. The semicoke formed contains >50% micropores. The mesopores present are also relatively small (3–7 nm).

The corrosive activity of coal-tar wash oils is investigated. An electrochemical method is proposed for assessing the corrosive activity of the oil with respect to carbon steel. The main sources of corrosive impurities in the absorbers are identified. The contamination of the oil is assessed on the basis of its breakdown voltage. The results are in excellent agreement with analytical monitoring of the wash oils. Gravimetric data for the corrosive activity of the fluids in the existing system show that alloyed molybdenum steels are the most durable structural materials in the distillation department. In systems with a closed final-cooling cycle, the corrosive activity of the coal-tar oils may be reduced by scrubbing with water. Quantitative selection criteria are established for the water used.

Means of utilizing coke-plant wastes are investigated. Their environmental impact is evaluated. A new method is developed for using heavy coal tars to generate producer gas. The electrical converter employed permits regulation of the gas composition so as to increase the content of flammable components. Conditions preventing the formation of carcinogens such as benzo[a]pyrene in the producer gas are created, in laboratory conditions.