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Vol 62, No 4 (2019)
- Year: 2019
- Articles: 7
- URL: https://journals.rcsi.science/1068-364X/issue/view/13988
Coal
Improved Coal Flotation with Sinterol Modifier
Abstract
The flotation of coal with different ash content when using Sinterol modifier is studied. If the modifier consumption is 1.0–3.0 g/t of coal fines, the extraction of the coal’s combustible mass in the concentrate is increased; the selectivity of the process is increased; and the loss of the coal’s organic mass with the flotation wastes is decreased. The improved flotation may be explained as follows. The Sinterol modifier is adsorbed on active sections of the coal surface by means of hydrogen bonds with its polar groups, in a configuration such that the hydrocarbon groups face the water. That results in a more hydrophobic surface of the coal particles and improves their floatability. The modifier is more effective in flotation when supplied before the collection agent.
121-127
Effect of Low-Temperature Pyrolysis of Shenfu Long-Flame Coal on Caking Properties of Coking Coal
Abstract
Pyrolysis of Shenfu long-flame coal at low temperature has been carried out in a tubular furnace to reduce the influence of the addition of non-caking coal on the caking property of coking coal. The influence of low temperature pyrolysis on the chemical composition and microstructure of Shenfu long-flame coal has been studied. Finally, the effect of low-temperature pyrolysis on the relative Giseeler fluidity and caking index has been investigated by mixing the Shenfu long-flame coal with Taozhuang fat coal in a certain proportion. The experimental results show that the active component content of Shenfu long-flame coal is slightly lower, while the inert component content increases slightly after low-temperature pyrolysis. The maximum mean reflectivity of Shenfu long-flame coal vitrinite group increases with the increase of final temperature of pyrolysis. The surface of long-flame coal tends to be dense and smooth, and the crystal structure of the Shenfu long-flame coal gradually changes to graphite crystal structure. Compared with the simple addition of long-flame coal to coking coal, adding long-flame coal after low-temperature pyrolysis can alleviate the weakening effect of adding non-cohesive material on the caking property of coking coal and therefore improve the quality of coke.
128-134
Coke
Structural Analysis of Needle Coke
Abstract
Industrial needle-coke samples from different producers are investigated by X‑ray diffraction and scanning electron microscopy. Their structural parameters La and Lc are determined, and their microstructure is investigated. A relation is observed between the structural parameters and morphology of the coke particles. Given the consistency of the results obtained by the two independent methods, X-ray structural analysis and scanning electron microscopy may be regarded as complementary tools essential to structural assessment and assignment of coke samples and also to specification of the thermal conditions for the production of high-quality anisotropic needle coke.
135-142
Calorific Value of Coke. 1. Prediction
Abstract
There is great scope for energy conservation in iron production. It is shown that blast furnaces and coke plants are the greatest consumers of energy and carbon in the steel industry. There are not even any optional guidelines for the calorific value of blast-furnace coke produced in Ukraine or elsewhere. Existing formulas for the calorific value of liquid and solid fuels do not permit prediction of the calorific value of blast-furnace coke with sufficient accuracy. The lack of reliable data regarding the influence of raw materials and production factors on the calorific value of blast-furnace coke prevents the identification of practical methods for its improvement.
143-149
Chemistry
Thermal Dissolution of Different-Ranked Coals in the Anthracene Fraction of Coking Tar
Abstract
The thermal solution of coal at different metamorphic stages (from lignite to Zh coal) in the anthracene fraction of coking tar is studied. Up to 69% conversion of GZh and Zh coal with an elevated content of plastic mass and polyaromatic fragments is observed in thermal dissolution. It is shown that thermal dissolution is a selective process, in which quinoline-soluble pitch-like products are mainly formed, with little formation of gases and distillates.
150-157
Viscosity and Wetting Properties of Pitch
Abstract
The viscosity, wetting properties, and fluidity threshold of coal and other pitches are considered. The fluidity threshold of coal pitch is determined, and the influence of heat treatment on this temperature is studied. The softening temperature and fluidity threshold of the pitch samples are compared. The relation between the viscosity of pitch and its composition, wetting properties, and mass loss on heating to 360°C is analyzed.
158-163
Comparison of the Coking Products from Heavy Petroleum Tars and Heavy Catalytic-Cracking Gas-Oil
Abstract
The slow coking of heavy petroleum tars and heavy catalytic-cracking gas-oil from AO Gazpromneft–Omskii NPZ (AO GPN–OPNZ) is considered. The liquid coking products of heavy oil residues are analyzed by gas chromatography, mass spectrometry, and IR spectroscopy. The variation in composition of the decomposition products in the coking of the two raw materials is described. The quality of the petroleum coke obtained is studied by optical microscopy and X-ray diffraction analysis.
164-168