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Актуальность исследования обуславливается интересом к обеспечению тепловых затрат технологий переработки нефти за счет побочных продуктов (нефтешлама), а также необходимостью снижения вредных выбросов технологических процессов. Цель: исследование возможности сжигания углеродного остатка, полученного при паровой газификации нефтешлама, в составе топливной композиции с добавлением торфа. Объект: углеродистый остаток нефтешлама, полученный после паровой газификации нефтяного шлама при температуре 600 °С, и топливная композиция на его основе с добавлением торфа (25 мас. %). Методы. Теплотехнические характеристики исследуемых образцов определены согласно ГОСТ Р 55661-2013, 33503-2015 и 55660-2013. Значения теплоты сгорания установлены при помощи калориметра АБК-1 (РЭТ, Россия), элементный состав - на анализаторе Vario Micro Cube (Elementar, Германия). Размер частиц УОН установлен при помощи растрового электронного микроскопа JSM-6000C (JEOL, Япония). Исследование процесса горения рассматриваемых образцов осуществлено с помощью дифференциального-термического анализатора STA 449 F3 Jupiter (Netzsch, Germany) и экспериментального стенда, оборудованного высокоскоростной видеокамерой FASTCAM СА4 5 (Photron, США). Характерные температуры плавкости золы и её состав определены согласно ГОСТ 2057-94 и ГОСТ 10538-87 соответственно. Результаты. Углеродистый остаток нефтешлама имеет превышающую торф и сопоставимую с бурыми углями теплоту сгорания и довольно низкую температуру воспламенения (220 °C), что обусловлено довольно высоким содержанием летучих веществ (Vdaf =64,3 %). Однако высокие значения зольности (Ad=60 %) и содержания серы (Sdaf=4,3 %) указывают на необходимость утилизации большого количества золы и улавливания окислов серы SOx. Показано, что совместное сжигание углеродистого остатка и торфа (25 мас. %) позволило снизить количество образующегося зольного остатка. Помимо этого, при добавлении 25 мас. % суховского торфа удалось снизить количество образующихся выбросов SO2 более чем в 3 раза. Этот эффект обусловлен взаимодействием газовой фазы с минеральной частью торфа, а именно, с карбонатами кальция и магния. The relevance of the research is caused by the interest in ensuring the thermal costs of oil refining technologies at the expense of byproducts (oil sludge), as well as the need to reduce harmful emissions of technological processes. The main aim is research of the possibility of burning the carbon residue obtained during steam gasification of oil sludge as part of a fuel composition with the addition of peat. Objects of the research are carbon residue of oil sludge obtained after steam gasification of oil sludge at 600 °C, and a fuel composition based on it with the addition of peat (25 wt. %). Methods. Thermotechnical characteristics of the studied samples are determined according to SS R 55661-2013, 33503-2015 and 55660-2013. Net calorific values of the peats were determined in the ABK-1 calorimeter (Russia), the elemental composition of the organic matter was determined using the analyzer Vario Micro Cube (Elementar, Germany). Particle size (СROS) was determined using a scanning electron microscope JSM-6000C (JEOL, Japan). The study of the combustion of the samples under consideration was carried out using the differential thermal analyzer STA 449 F3 Jupiter (Netzsch, Germany) and an experimental stand equipped with a high-speed video camera FASTCAM CA4 5 (Photron, USA). The characteristic melting temperatures of ash and its composition are determined according to the SS 2057-94 and the SS 10538-87, respectively. Results. The carbon residue has a calorific value exceeding peat and comparable to brown coals and a rather low ignition temperature (220 °C), which is due to a rather high content of volatile substances (Vdaf =64,3 %). However, high values of ash content (Ad=60 %) and sulfur content (Sdaf=4,3 %) indicate the need to dispose of a large amount of ash and capture sulfur oxides SOx. It is shown that the joint combustion of carbonaceous residue and peat (25 wt. %) allowed reducing the amount of ash residue formed. In addition, when adding 25 wt. % of sukhovskoу peat it was possible to reduce the amount of generated SO2 emissions by more than 3 times. This effect is due to the gas phase interaction with peat mineral part, namely, with calcium and magnesium carbonates.

The combustion of some types of biomass leads to the formation of ash deposits, which reduce the efficiency and reliability of boiler equipment. The mechanism of formation of these deposits is still not fully understood. The aim of this work is a comprehensive study of the mineral part of the flour-milling waste (wheat bran) to determine the possibility of using them as fuel. Separation of bran into fractions with different densities by sedimentation was carried out in the work. X-ray fluorescence analysis and scanning electron microscopy were used as the main research methods. As a result of the study, it was found that the mineral part of wheat bran is sintered at a temperature of above 675 °C. It has been suggested that in the process of bran combustion, the Ca/K ratio is an essential factor affecting the sintering of the ash residue. It was experimentally shown that the addition of calcium carbonate to bran in an amount of 3 wt% and more eliminates the sintering of the ash residue.

This paper is devoted to a study of the nature and origin of the mineral matter in the Vasyugan Mire in Western Siberia. Based on mineralogical and geochemical analyses, new results were obtained concerning the mineral composition within the bottom part of the peat deposit for different landscape zones in the Vasyugan Mire. This part of the peat deposit represents a transition sequence from peat through organo-mineral sediments (OMS) to basal loams and is characterized by a gradient change in the physicochemical and environmental conditions with depth. In the same sequence, pH and peat ash yield increase, while moisture decreases. The clay minerals identified in the basal layers of the mire, consisting of loam, OMS and peat, include illite, chlorite, kaolinite and smectite. All these clay minerals found in the OMS and peat layers are believed to have been inherited with little change from the underlying loam layer during the initial transient stage of mire development. That this is indeed the case is strongly suggested by the extraordinary correspondence in the mean content of over 40 trace elements between the OMS and loam layers. In the overlying peat layer, however, some elements, including U, W, Sb, Sn, Mo, Zn, Cd, Nb, Ta, Br and B, are present in higher concentrations than in the OMS and loam. Scanning electron microscope observations suggest that this can be at least partly accounted for by the precipitation of sulfide phases in the strongly reducing and acidic environment of the peat, although whether by inorganic or microbial processes is unknown. The age of the Vasyugan Mire within the Holocene succession is discussed and it is concluded that it developed either during the Atlantic Period (8 ka–6 ka BP) or during the upper part of the Sub-Boreal Period (4 ka BP).

This study demonstrates the formulation of slow-release fertilizers by the mechanical activation of a mixture of powdered clays and urea in the ratio 2:3, using planetary or ring milling techniques. The activation produces micro-aggregates of composites with intercalated clay and urea and is rimmed by the latter. Smectite-urea and glauconite-urea mixture shows an intercalation between urea and clay from the beginning of activation. A shift of X-Ray Diffractional parameters and the intensities of FTIR peaks record the systematic structural changes of the composites with increasing duration of activation. The maximum intercalation of clays and urea requires operation times of 20 and 60 min in planetary and ring mills, respectively. The external urea forms a uniform coating around the intercalated structure using the planetary mill, and it keeps on growing as the operation time increases. Therefore, this investigation reveals the optimum activation conditions for the formation of composites with layered structures. While the direct application of urea releases nitrogen to the soil at a fast rate, the resulting composites are likely to liberate the nutrient at a slow rate. Additionally, the composites made from a mixture of glauconite and urea releases potassium at a slow rate. The resultant composites meet the criteria of multifunctional slow-release fertilizers.

Peat belongs to the slowly renewable biomass resources, therefore its use as an energy source helps to reduce the negative impact on the environment. However, its use in the energy sector is gradually decreasing due to high operating costs because of the characteristics of peat. The aim of this work is a comprehensive study of the peat characteristics and the development of recommendations for its effective use. In this paper, we consider the widespread methods for studying fuel (thermo-technical and fusibility characteristics determination, X-ray fluorescence and phase methods), as well as the original approach of separation by sedimentation in liquids of various densities. The peat separation by sedimentation in liquids of various densities made it possible to obtain a low-ash peat fraction comparable in characteristics to brown coals and a highly mineralized fraction (heavy fraction). On the example of grain processing waste, it is shown that the addition of a 5% of heavy peat fraction to bran prevents the formation of strong slag deposits and can be recommended for co-burning. This allows us to consider the separation by sedimentation in liquids of various densities as an effective tool for using highly mineralized types of biomass in energetic sector.

The combustion of some types of plant biomass leads to the sintering of their mineral part with the formation of deposits on the heating surfaces. Operational experience shows that the joint combustion of several types of biomass can help to solve this problem. The aim of this work is to study the effect of co-combustion of waste from flour milling and highly mineralized peat on the sintering of the ash residue. Various analysis methods (ISO, EDXRF, TGA, and DSC), as well as a experiment in the constructed experimental combustion unit, were used in the work. Wheat bran with a low initial deformation temperature (tA = 780 °C) and highly mineralized peat from the Tomsk region (Ad = 22.8%) were taken for the investigation. These resources are unpromising when considered individually as fuel. Using a bran-peat fuel mixture with a peat fraction of 5 wt % and more makes it possible to obtain an unsintered powdery ash residue. The optimal amount of peat addition to bran during combustion is 5 wt %. A decrease in the proportion of peat leads to sintering of the ash residue, an increase in the proportion of peat increases the ash content of the mixture.