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Том 60, № 1 (2017)
- Год: 2017
- Статей: 7
- URL: https://journal-vniispk.ru/1068-364X/issue/view/13932
Coal
Polyene model of coal structure and metamorphism
Аннотация
Eight coal ranks (G, GZhO, GZh, K, KO, KS, and T) are investigated by IR spectroscopy in the range between 1800 and 650 cm–1, with polynomial decomposition of the spectra obtained. The similarities and differences in the IR spectra for two series of coal are noted: specifically, fat coal (Zh, GZh, GZhO, and G) and coking coal (K, KO, KS, and T). For both series, we consider the regions of the spectra containing narrow absorption bands. On passing from Zh and G coal in the fat set and from K to T coal in the coking set, the intensity of the IR absorption bands at 1450 and 1370 cm–1 declines, on account of deformation C‒H vibrations of the CH2 and CH3 groups, while the absorption of oxygen-bearing groups appears. These experimental data are inconsistent with accepted concepts regarding the metamorphism on passing from gas coal (rank G) to lean coal (rank T).
1-6
Characteristics of Mongolian coal
Аннотация
Samples of Mongolian coal from the Khuden field are studied (specifically, technical and elementary analysis, heat of combustion, mineral characteristics, petrographic composition, clinkering properties, degree of oxidation, mechanical strength, and thermal stability). The Mongolian coal samples are classified in terms of genetic and technological parameters, and prospects for the use of such coal are assessed.
7-16
Thermal analysis of coal ash
Аннотация
Carbon materials are widely used in metallurgy and in the power industry as fuels and reducing agents. Coal, although inexpensive, is difficult to use, on account of its high ash content. In the operation of industrial systems, the ash might melt, with the subsequent formation of buildup. In addition, coal ash must be stored in tailings. Therefore, fuel oil and natural gas are more commonly used. Ash tailings pose a significant environmental problem in Russia. Various methods are known for the use of ash in construction. However, their adoption has been slow, on account of the complications caused by the variability in ash composition and properties. The industrial applicability of ash may be assessed by studying the physicochemical processes that accompany ash heating and determining the relation between the properties and mineral composition of ash. An important property of ash is its fusibility, which may vary widely on account of its nonuniform mineral composition. Traditionally, the fusibility of ash is determined on the basis of State Standard GOST 32978–2014 (ISO 540:2008). As in any visual method, the results are highly inaccurate. Existing theoretical analyses employ fusibility values obtained on the basis of the international standard. In this context, there is a pressing need to develop and test new methods of determining the melting point of ash.
17-22
Coke
New gas exhaust system for use in the dry quenching of coke
Аннотация
A new design is proposed for the dry-quenching chamber in coke production. As shown by research on a cold physical model, the new gas distributor and gas-exhaust system ensure that the motion of the cooling gas resembles ideal displacement. The total volume of the dead zones and zones with reduced cooling rate is no more than 15% of the dry-quenching chamber.
23-27
Ignition of droplets of coal–water–oil mixtures based on coke and semicoke
Аннотация
To permit expansion of the resource base and utilize industrial waste, coal–water–oil fuels may be prepared on the basis of coke and semicoke, as well as common petroleum derivatives (fuel oil and spent compressor, turbine, and transformer oils). The minimal oxidant temperature corresponding to stable ignition of coal–water–oil slurries is established. Typical variation in fuel temperature in the course of reaction is determined, as well as the delay time of ignition and the total combustion time for individual droplets of such fuel suspensions. For droplets of initial size 0.5–1.5 mm, the influence of the various factors (droplet size, oxidant temperature, and concentration of the components) on the threshold (minimum) temperature and inertia of ignition is studied. It is shown that stable ignition of coke and semicoke in such fuel is possible at moderate oxidant temperatures: 700–1000 K.
28-36
Chemistry
37-41
Ozonolysis of isoquinoline in a polystyrene-based sulfonate cation exchanger
Аннотация
Nanoreactor ozonolysis of aromatic heterocycles is studied. It is found that cinchomeronic acid (which is used in the production of medical preparations) may be obtained by the nanoreactor ozonolysis of isoquinoline, which is a component of the heavy pyridine bases obtained in the distillation of coal tar.
42-45