Search

The coking properties of coal pitch depend significantly on its fractional composition, which determines the set of structural components involved in meso-phase formation. The optimal combination of high-molecular aromatic compounds, polycyclic compounds of intermediate molecular mass, and hydrogen-donor hydroaromatic components corresponds to a ratio of pitch fractions α: β: γ = 1: 2: 2. This is typical of coal pitch with a softening temperature of 75–85°C. Such pitch is the best clinkering additive to coking batch, resulting in the production of coke of maximum strength.

The carbonization of low-ash lignite in a fluidized bed at 650–800°C is considered. The dependence of the basic process parameters on the air flow rate, the coal consumption, and the fractional composition of the coal is investigated. The characteristics of lignite coke obtained by the TERMOKOKS-KS process are presented.

Simulation confirms literature data regarding the higher yield of light fractions (density ρ ⩽ 1.28–1.30 g/cm3) from reduced coal than from slightly reduced coal. The predominance of light fractions with an elevated hydrogen content in the coal’s organic mass facilitates the formation of physicochemical properties associated with high degrees of reduction. The degree of reduction is related to the content of such fractions in the coal. This is evidently the case for a whole range of caustobioliths and is especially pronounced for oil, whose value is directly related to the content of light fractions (ρ ⩽ 0.84–0.87 g/cm3).