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Relevance. The need for effective utilization of biomass waste generated in significant quantities. Pyrolysis, accompanied by exothermic reactions, is a promising way of biomass processing. Aim. Assessment of the possibility of covering the thermal costs of plant and animal biomass pyrolysis due to heat release during decomposition. Methods. Proximate and ultimate analysis of biomass are determined according to certified methods. Thermal analysis of the studied raw materials was carried out on a Netzsch STA 449 F5 Jupiter synchronous thermal analyzer with an integrated gas analyzer QMS 403 Aeolos; quantitative yield of pyrolysis products was determined according to GOST 3168-93, gas composition was established using the gas analyzer TEST-1 (БОНЭР, Russia). Results and conclusions. According to the results of thermal analysis, it was found that pyrolysis of plant (pine nut shells) and animal (cattle manure) biomass is accompanied by exothermic reactions associated with the organic part decomposition in the temperature range 240–700°C. The value of heat release of exothermic reactions during pine nut shell destruction is 1.39 MJ/kg, a similar value during manure decomposition is 0.31 MJ/kg. This amount of heat allows you to fully cover the thermal costs of pine nut shell pyrolytic processing, the share of covering the thermal costs of manure pyrolysis is ∼30%. An additional source of heat is pyrolysis gaseous products with energy potential equal to 3.28 and 1.58 MJ of thermal energy per 1 kg of processed pine nut shells and manure, respectively.

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 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 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.