Vol 61, No 6 (2018)

Among the properties of coal that must be studied in order to optimize its preparation for coke production and deep processing are the interactions of adsorbed materials—in particular, water, methane, and carbon dioxide—with its surface. An important aspect of these interactions is phase transformation of the adsorbed materials in the internal porous structure to form hydrate or ordinary ice. In regular coal, a hydrate of carbon dioxide is formed at a CO₂ pressure of 2–4 MPa and temperatures below 10°C, when the moisture content of the coal exceeds the threshold value. However, at the same moisture content, no ice is formed at temperatures between +13°C and –13°C, while decomposition of the hydrate is observed close to the equilibrium curve. For gases that do not form hydrates (helium, nitrogen, argon) in the given temperature and pressure ranges, increasing the pressure to 12 MPa has no influence on the solidification of sorbed water and ice formation.

To date, Giprokoks designs have been used for all Russian coke batteries. The condition of these coke batteries has been deteriorating from year to year. The mean life of Russian coke batteries is 32 years, with values of 35 years for OAO EVRAZ ZSMK, 40 years for OAO MMK, 33 years for OAO Altai Koks, and 30 years for PAO Severstal’. The condition of the coke ovens determines the stability of steel output. The Russian coke industry faces the challenge of renewing (modernizing) its worn-out coke batteries. Changes are proposed here in some refractory components used in coke-battery linings. These proposals may be of interest to coke-battery designers and to contractors preparing for the reconstruction (or construction) of coke batteries.

The potential of oil-processing byproducts and various aliphatic and cyclic oxygen-bearing compounds as coal-flotation agents is investigated. In the search for highly effective coal-flotation agents of specific structure and elemental composition, one useful criterion is the energy of the hydrogen bond in the intermolecular complex formed by the coal-flotation agent and the coal’s organic mass. The hydrogen-bond energy in such complexes is found to be higher than that in the intermolecular complex formed by the water and the coal’s organic mass. Accordingly, the reagents considered are effectively adsorbed on the coal surface and are highly active in flotation. The use of oil-processing byproducts that contain cyclic organosilicon compounds in their group chemical composition considerably improves flotation; the reagent consumption is lower than in flotation based on coal-enrichment byproducts. We recommend oil-processing byproducts that contain cyclic organosilicon compounds in their group chemical composition for industrial tests in flotation at Russian coal-enrichment plants.

The production of fuel granules on the basis of various types of waste (wood shavings, spent malt, peat, sunflower husks, leaves, and carbon black) is considered. The calorific value and ash content of the granules are determined in comprehensive tests. A model is proposed for the multistage combustion of fuel granules.