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The problem of assessing the sedimentation stability of water-coal suspensions, which are a promising type of fuel, possessing the advantages of both liquid fuels and coal, which can be effectively used as a substitute for liquid petroleum fuel (fuel oil), is considered. However, coal-water suspensions have not found wide application at present, which is promoted, in particular, by unresolved issues related to their sedimentation stability: in the production, storage, and transport of suspension, an important qualitative characteristic is its stability over time: the higher it is, the more qualitative is the suspension. The paper proposes a method of solving the problem of predicting the value of particle sedimentation during the sedimentation process, which allows us to calculate the dynamics of sediment accumulation over a certain period of time from the beginning of sedimentation at a given depth of dispersion. The implementation of the calculation method as a systematic approach to determining the dynamics of sediment accumulation is shown on the example of sedimentation analysis data of 50 % water-coal suspension from coal from the Neryungri deposit. It is shown that the proposed method of solving the problem of predicting the size of sedimentation of particles during the sedimentation process allows to calculate the dynamics of sediment accumulation for a certain period of time at a given depth, as well as to determine the minimum sedimentation time, at which the particles of maximum size sediment completely.

One of the methods of initial properties of solid fuels changing by their organic mass oxidation is considered in the paper. Creation of innovative ways of intensification of existing solid fuels processing and their adoption by industry has always been and remains an actual task. Thus the chemical process is the most important stage of raw materials processing into target products. Chemical exposure allows to optimize the technological mode, expanding the scope of control of technological process parameters and, to a certain extent, modify the properties of the resulting products. The article presents the results of experimental research of influence of preliminary oxidation on the lignite organic mass from Kharanorsk and Kangalas deposits by different chemical reagents to determine a degree of this process impact on the efficiency of their processing into humic substances. Inorganic and organic oxidizers of different concentrations were used as reagents. The greatest effect for increasing the humic acids yield was observed when using 6-10 % hydrogen peroxide for oxidation, and 10 % hydrochloric acid. The results of experiments on the coal preoxidation effect can be used as a basis for the development of a new method of lignites processing into humic substances.

The paper presents the results of research for sorbents preparation when combining the processes of chemical modification and steam-gas activation of lignite from the Kharanorsk deposit (Zabaikalsky Krai). The experimental studies were carried out by two ways of activation methods combination: parallel and successive exposure on feedstock. The lignite processed by chemical reagent (KOH) was exposed to steam during the whole period of thermolysis under the parallel action. Under successive exposure, the thermolysis was performed in two stages - first without steam supply, then with steam-gas activation. In the work the optimal parameters of the process of combining the chemical and steam-gas lignite activation methods were determined and the quality of the generated sorbents was studied. The efficiency of combined activation was estimated by comparing the sorption characteristics of the samples with the results obtained during chemical and steam-gas activation as autonomous processes and with the requirements to these characteristics of industrially produced active carbon grades. Combined activation of lignite allowed to increase the value of iodine adsorption activity in comparison with autonomous steam-gas activation by 1.8-2 times, chemical activation - by 2.7-10 %. The obtained values of iodine adsorption activity at combination of chemical modification and steam-gas activation exceed the value of 100 % (1000 mg/g) that meets the requirements to high quality industrially produced active carbons of SKT-0 grade.

This article studies the possibility of intensification of Kharanorskoe deposit brown coal alkaline activation by way of electromagnetic microwave radiation (EMR) exposure in order to obtain sorbents. There is data that presents investigation of qualitative and adsorption properties of sorbents obtained from 0-2 mm brown coal samples impregnated with potassium hydroxide at a KOH / coal of 1 g / g weight ratio and subjected to thermolysis at 800 °C in the thermal shock mode. The authors carried out a detailed analysis of three options for thermal treatment of the coal-alkali mixture ahead of thermolysis: coalalkali mixture drying to indiscrete mass, EMR treatment and combination of ones. The design of a laboratory microwave oven for heat treatment of raw materials based on the use of EMR at a frequency of 2,450 MHz is presented. It was found out that the effect of electromagnetic microwave radiation with a frequency of 2.450 MHz makes it possible to increase the adsorption activity on iodine by 4-6%, reaching a value of 97%, to significantly shorten the time of preliminary heat treatment of the coalalkali mixture and to shorten the thermolysis time when sorbents obtain.