Том 60, № 10 (2017)

In coke production, the moisture content of the initial coal is an important parameter. The moisture present in the pores of coal changes the properties of the coking batch. Note also that, together with methane and/or carbon dioxide, water may form gaseous hydrates in the coal bed. In the present work, to study the state of the moisture in coal, attention focuses on eight samples of natural gas saturated to constant moisture content in an atmosphere where the relative partial pressure of water vapor is 91%. The moisture sorbed from the atmosphere has a U-shaped dependence on the metamorphic stage of the coal, with a minimum at coking coal (K coal). In similar conditions, the more mature T and A coal contains twice as much moisture as K coal, while the younger D and G coal contains about four times as much moisture. Thermogravimetric analysis of coal samples saturated to constant moisture content permits calculation of the rate of mass loss and activation energy for the evaporation of moisture in the heating of the given samples. For each coal sample, the temperature range where the evaporation of moisture may be described by a first-order Arrhenius equation is determined. The upper limit of this range is compared with the temperature corresponding to maximum rate of mass loss and also with the temperature corresponding to the maximum thermal effect.

By determining the distribution function of the biochemical microelement concentrations on the basis of the gross concentrations in coal, better estimates of the concentrations in the paleophytomass may be obtained. The proposed method permits estimation of the biogeochemical concentrations at the significance level α = 0.05 for coal with low and relatively high microelement content. For coal with anomalous microelement content, α = 0.01.

A new system for final cooling of coke-oven gas has been installed in the byproduct-capture shop of the coke plant at Durgapur Steel Plant (India). This system, designed by AO VUKhIN under a contract with Bengal Tools Limited (now BTL EPC, India), also removes naphthalene from the gas and ensures the absorption and distillation of benzene. The main design features are outlined. The treatment technology for the coke-oven gas is described; along with the organization of the final cooling and the removal of naphthalene, the trapping of phenolic hydrocarbons by petroleum absorbent, and the distillation of absorbing oil. This system ensures the specified quality of the products—purified coke-oven gas and raw benzene.

The physicochemical properties of Kuznetsk Basin coal are studied in the laboratory. The composition and specific surface of the coal samples are compared, as well as their adsorption of CO₂ at different pressures and temperatures. In an atmosphere typical of a mineshaft, coal of moderate metamorphic development is characterized by the greatest sorptional potential in dynamic conditions. Current methods permit assessment of the sorptional properties of coking coal, regarded as a coal–methane system.