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Relevance. The need of the Tomsk region for valuable energy resources obtained from local low-grade resources to develop iron ore deposits available in the region and cover energy needs. Aim. To study gaseous and solid products obtained from low-grade brown coal of the Talovsky deposit (Tomsk region) under microwave pyrolysis conditions in relation to the energy and metallurgical industries. Objects. Brown coal of the Talovsky deposit (Tomsk region). Methods. Certified SS methods to determine thermal characteristics and elemental composition of coal organic and mineral parts, the "transmission-reflection" method for measuring imaginary (ε'') and real (ε') components of the complex dielectric permittivity, physical experiment, gas analysis, Brunauer–Emmett–Teller method for measuring texture characteristics. Results. Brown coal of the Talovsky deposit has high values of moisture and ash contents for operating conditions, which leads to a low calorific value. Such characteristics make it possible to classify coal as a low-grade fuel, which indicates the inexpediency of its use as a raw material for the energy and metallurgical industries. Thermal processing by means of microwave pyrolysis makes it possible to obtain a high-calorie (heat of combustion over 21 MJ/m3) and environmentally friendly (hydrogen content over 29%) gaseous fuel from the low-grade brown coal of the Talovsky deposit. The resulting solid carbonaceous residue has an ash content of over 48%, which required its chemical treatment in a solution of HF and HCl. As a result of the solid carbonaceous residue treatment, its ash content decreased by more than 38%, the sulfur content – by more than 1.5 times. According to its characteristics, the resulting product corresponds to the currently available carbonaceous products – semi-coke, coke and carbon reducing agent for ferroalloy production.

The relevance of the study is caused by the need to find technologies that can improve the environmental friendliness of the use of organic fuels in the process of energy supply. The main aim is research of microwave pyrolysis of solid organic fuels with different degrees of metamorphic transformation. Objects: solid organic fuels with varying degrees of metamorphic transformation, namely, wood waste (pine sawdust), lowland peat (Sukhovskoe deposit, Tomsk region), brown coal (Talovskoe deposit, Tomsk region), hard coal (grade D, Kuznetsk basin, Kuzbass). Methods. The characteristics of the initial fuel were determined according to generally accepted methods: humidity – SS R 52917-2008, volatile matter yield – according to SS R 55660-2013. The ash content of sawdust was determined according to SS R 56881-2016, peat – SS 11306-2013, coal – SS R 55661-2013. The fundamental difference between the standards used in terms of determining the ash content lies in the prescribed parameters of the analysis procedure (temperature, speed, time). The heat of combustion was determined using an ABK-1V calorimeter (RET, Russia) in accordance with SS 147-2013. The elemental composition of the feedstock and the solid carbon residue after its processing (C, H, N, S) was determined using a Vario Micro Cube analyzer (Elementar, Germany), using a standard sample (Sulfanilamide) as a verification. Research of the processing of the concerned fuels by the method of traditional slow-bed pyrolysis was carried out by the method of synchronous thermogravimetric analysis and differential scanning calorimetry using an STA 449 F3 Jupiter instrument (Netzsch, Germany). Microwave pyrolysis was implemented on a specially designed experimental stand (magnetron power 750 W, carrier frequency 2,45 GHz). The pyrolysis gas composition (the content of components such as H2, CH4, CO, СО2) was recorded in real time using a Test-1 gas analyzer (Boner, Russia). Results. By the method of differential thermal analysis, it was established that the temperature of the end of thermal transformation for biomass (sawdust and peat) is 600–650 °C, for brown coal – 850 °C, for hard coal – 900 °C. Comparing the results of slow-bed and microwave pyrolysis, it was noted that during microwave pyrolysis of fuel, 9,5–11,7 % less solid carbon residue is formed, and the yield of volatile (liquid and gaseous products) increases. At the same time, the pyrolysis gas generated in the process of microwave pyrolysis almost does not contain ballast CO2 in its composition, which, together with the low yield of carbonaceous residue, indicates a higher efficiency of thermal fuel processing compared to slow-bed pyrolysis. It is noted that with an increase in the degree of fuel metamorphism in the process of microwave pyrolysis, the share of generated synthesis gas (Н2+СО) in relation to the amount of methane obtained decreases, which is associated with the composition of the initial processed raw material: change of (СО+Н2)/СН4 in the pyrolysis gas correlates with the change of (Н+О)/С in initial fuels.

The relevance of the research is caused by the interest in ensuring the thermal costs of oil refining technologies at the expense of by-products (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 work relevance is caused by the need to study the changes of biomass thermophysical characteristics in its thermal transformation in relation to the design of technological equipment and energy use. The main aim of the research is to study the thermophysical characteristics during slow pyrolysis of biomass with different mineralization amount. Objects: biomass resources with different amount of mineralization ­– straw (Ad=2,8 %), nonconforming wheat bran (Ad=6,9 %), lowland peat of the Sukhovsky deposit (Ad=22,8 %). Methods. Thermotechnical characteristics of biomass samples and their carbon residue are determined according to certified methods (GOST R 54186-2010 (EN 14774-1: 2009), GOST R 56881-2016 (E1755-01), GOST 11305-2013, 11306-2013, GOST 32990-2014 (EN 15148: 2009)); values of the calorific value were determined using the ABK-1 calorimeter (RET, Russia) in accordance with GOST 147-2013 (ISO 1928-2009); elemental analysis of organic part was carried out on a Vario Micro Cube (Elementar, Germany) device; thermal processing was carried out by differential thermal analysis and physical experiment; the thermophysical characteristics of the biomass and its carbon residue were measured by laser flash method using the thermal conductivity analyzer Discovery Laser Flash 1 (DLF-1); the true density was measured using an automatic gas pycnometer Ultrapyc-1200e (Quantachrome Instruments, USA); the carbon residue structure was studied by scanning microscopy VEGA 3 SBU electron microscope (TESCAN, Czech Republic). Results. Straw and bran pyrolysis proceeds in two stages, differing in the average rate of decomposition – (0,38…0,41) %·°C–1 and 0,09 %·°C–1 respectively. Peat decomposition occurs in the whole temperature range (220–500 °C) with an average decomposition rate of 0,11 %·°C–1. It was found that the thermal conductivity of carbon residue from straw and bran, which have a relatively low ash content for biomass, does not significantly change up to 400 °C, after which this value increases. The heat capacity of these samples increases with the temperature of their production to 300 °C, after which it sharply decreases. The carbon residue obtained at 500 °C has a higher heat capacity value compared to the residue obtained at 400 °C. These changes can be explained by decomposition of biomass organic part components – cellulose and lignin. The heat capacity and the thermal conductivity of sukhovsky peat carbon balance, have a high mineralization amount (Ad=22,8 %), decrease in all temperature range, due to the inorganic components share increase in result of organic part decomposition, which is confirmed by the solid phase density increase.

The relevance of the research.The solution of environmental problems in the agricultural sector is possible throughthe use of new slow-released or controlled release fertilizers.This article presents options for using montmorillonite as a component of modern nitrogen fertilizers with controlled properties and the results of studying mineral transformations in the mechanochemical activation at various parameters. The main aim of the work was to evaluate activation mechanisms of the montmorillonite as an inhibitor of nitrogen composites for creating slow-release fertilizers. The methods: mechanochemical activation by planetary and ring mills, X-ray diffraction, scanning electron microscopy, infrared spectroscopy, differential thermal analysis. Results.The proportion of intercalated urea in montmorillonite (for M1N1 mixtures) is slightly changed within 22,3...23,2% for the planetary mill activation for 3, 8 or 11 minutes. The maximum intercalation degree of 23,2% was achieved in the activation for 3 minutes. However, about 40...50% of the aggregated particles are covered with an outer shell of excess urea up to 2,5 µm in the thick after an 11-minute operation for the planetary mill. The proportion of intercalated urea in montmorillonite is slightly changed from 23,2 to 21,6% for the activation time increases from 30 to 120 minutes in a ring mill. While the activation time was increased, urea microcrystallites were formed on the surface of mineral particles. Mineral products synthesized by planetary or ring mill activation have the potential to be used as slow-release fertilizers with several beneficial functions. Composites synthesized with 11-minute or 120-minute planetary or ring mills, respectively, are characterized by two types of nitrogen. Fertilizers will initially release nutrients at a high rate from the outer urea film. After that, exchangeable nitrogen will be released from the interlayer space of montmorillonite, thereby providing prolonged nutrition of the plants.

The relevance of the study is caused by the tendency to increase the share of renewable energy in the fuel and energy balance to reduce the harmful effects on the environment. The main aim is to determine the kinetic parameters of biomass pyrolysis by G. Friedman's method based on the results of differential thermal analysis. Objects: straw, grain processing waste (wheat bran), cedar nutshell, pine sawdust, lowland peat of the Sukhovskoe field, as well as livestock waste from cattle. Methods. Thermotechnicalcharacteristics of biomass samples are determined according to certified methods (GOST 11305-2013, GOST 11306-2013, GOST R 54186-2010, GOST R 56881-2016, GOST 32990-2014); values ​​of the calorific value were determined using the ABK-1 calorimeter (RET, Russia) in accordance with GOST 147-2013 (ISO 1928-2009); elemental analysis of its organic part was carried out on a Vario Micro Cube (Elementar, Germany) device; the kinetic characteristics of low-temperature pyrolysis of biomass were determined by G. Friedman's method based on differential thermal analysis carried out at a temperature of 313–1273 K at a heating rate of 5, 15 and 30 K/min. Results. Thermal decomposition of biomass in the range of 313–1273 K occurs in two stages: the first stage proceeds in the temperature range from 463–488 to 623–653 K and is characterized by a sharp decrease in the mass of samples from 24 (peat) to 63% (sawdust); the second stage is observed from 623–653 to 873 K with a significantly smaller change in the mass of the samples (from 9 to 14%).With a further increase in temperature, the organic part of the samples practically did not undergo transformation, changes occurred only in the mineral part of peat at a temperature of 923–1123 K and were associated with the decomposition of calcium carbonate.The dependences of activation energy (Ea) on the degree of biomass conversion (w/w0) were determined, according to which its average values were calculated: for straw – 21,4 kJ mol–1; for sawdust – 20,7 kJ mol–1; for shell – 24,2 kJ mol–1; for livestock waste from cattle – 23,1 kJ mol–1; for bran – 33,1 kJ mol–1; for peat – 24,0 kJ mol–1.The values of the pre-exponential factor (A) for the studied biomass species are in the range 82,42–2377,01 h–1.

The relevance of the research is caused by the need of renewable energy sources share increase in the fuel and energy balance to reduce harmful impact on the environment. The main aim of the research is to evaluate the possibility of woody biomass and peat pyrolysis due to heat from the organic part decomposition of the raw material. Objects: peat samples from two deposits of the Tomsk region, promising for energy development, – Sukhovsky and Arkadievsky, as well as wood waste of two types – chips and sawdust. Methods: physical experiment and differential thermal analysis. Thermotechnical characteristics of woody biomass determined by the methods SS R 56881-2016, SS 33503-2015 and SS R 55660-2013; thermal characteristics of peat – using the SS 11306-2013, SS 11305-2013 and SS R 55660-2013. Calorific value of raw materials determined in the bomb calorimeter ABK-1 (RET, Russia), the elemental composition is determined by the analyser Vario Micro Cube (Elementar, Germany) taking into account the carbon dioxide content of the carbonates, established by volumetric method according to GOST 13455-91. Results. The authors have established the optimal parameters of pyrolytic processing for various types of biomass, such as pyrolysis temperature and moisture of the raw material. The optimum temperature for pyrolysis of wood waste in the air-dry state, is 400 °C, at which the total thermal effect is maximum and equal to 36,3 kJ/kg for sawdust and 78,8 kJ/kg for wood chips, for sukhovskoy peat at 500 °C total heat effect is equal to 149,7 kJ/kg. The maximum values of moisture, providing coverage of heat costs due to the heat of exothermic reactions, at these pyrolysis temperatures were 10 % for wood waste and 14 % for sukhovskoy peat. The value of the total thermal effect of Arkadievsky peat pyrolysis even in the dry state has a negative value.

The relevance of the research is caused by the need to involve renewable biomass (in particular, peat) to generate heat and electrical energy. This will partially solve the problem of resource-deficient regions, depending on the supply of fuel from developed coal deposits. The main aim of the research is the investigation of thermal characteristics and the mineral matter of the peat of a number of large deposits of the Tomsk region to assess the possibility of their energy use. Objects of researches are the samples of low-moor peat from Sukhovskoye and Arkadyevskoye deposits and one of the Tomsk region deposits. Methods. Thermal characteristics of the studied samples were determined according to GOST 33503-2015 (ISO 11722:2013), 55661-2013 (ISO 1171:2010), 55660-2013 (ISO 562:2010). 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). Peat mineral matter composition was studied by X-ray fluorescence analysis using an EDX-720-P spectrometer (Shimadzu, Japan) as well as by X-ray diffractometry using a Shimadzu XRD7000 diffractometer (CuKα-radiation) with a Shimadzu CM-3121 monochromator counter. Typical ash melting points were determined according to GOST 2057-94 (ISO 540-81). The structure of the samples under study was examined by scanning electron microscopy using a TM 3000 electron microscope (Hitachi, Japan). Results. On the basis of the obtained results, it can be concluded that, due to the high ash content, the use of okolotomsky peat for chamber-type combustion is impractical. However, this resource can be considered as a mineral fertilizer in agriculture due to the presence of such elements as phosphorus, potassium. The high content of carbonates indicates the possibility of its using as an additive to high-sulfur coal to reduce emissions of sulfur oxide SOx. The characteristics of sukhovskoу and аrkadyevsky peat make it possible to consider them as an alternative to imported fuel. The preferred method of energy use of peat from Tomsk region fields is its combustion in a fluidized bed.