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Gasification is one of the promising technologies for the use of solid fuels in power generation, chemical industries, and a number of related areas. Despite a significant amount of theoretical and experimental work performed in Russia, one of the key factors that limits the widespread commercialization of gasification technologies is the lack of practical experience of operation under industrial conditions or those close to them. To gain experience in managing the fixed-bed coal gasification technology, in autumn 2019, specialists of Tomsk Polytechnic University, based on the Ekoenergetika 4.0 (Ecoenergy Generation) research center in Tomsk, tested Russia’s first pilot fixed-bed gasifier with a capacity of 4 t of fuel per hour, which was developed at the All-Russia Thermal Engineering Research Institute. The tests were conducted using coals of four grades of the Kuznetsk and Kansk-Achinsk basins, viz., anthracite, long-flame and lean coals, and lignite. As a result of the tests, the technical feasibility of both individual components and the gasification plant as a whole was proven. In the course of the tests, high-quality synthesis gas was obtained with a calorific value in the range 6.0–8.3 MJ/m3, which makes its use as a fuel in combined-cycle plants with the reliable and stable ash removal possible. The possibility of using the gas produced in the tests of the fixed-bed gasifier for the synthesis of liquid hydrocarbons by the Fischer–Tropsch process has been experimentally established. Further, the possibility of producing coke and semicoke in the gasifier has been proven. The assessment of the reliability of the gasification plant performed using the ANSYS software based on the test data has shown a satisfactory lifetime of the plant with the expected service life of the most stressed gasifier components of 68 000 h.

The harmful emissions from traditional organic fuels combustion cause irreparable harm to the environment, which leads to the conclusion that it is necessary to reorient the energy sector to renewable energy sources such as biomass. Traditional methods of combustion are of little use for the energy use of biomass. This fact forces us to search new efficient technologies for its processing. Pyrolysis is one of the most universal and promising areas of biomass processing. However, its implementation requires significant heat costs, which has a considerable impact on the result of the feasibility study. The aim of the work is to study the thermal effects observed in low-temperature pyrolysis and to assess the possibility of autothermal biomass processing. Straw, chips from various types of wood, pine sawdust and peat from two deposits of the Tomsk region (Russia) were considered as a biomass. A physical experiment, differential thermal analysis, gas chromatography and heat balance equations were used in the work. It has been established that low-temperature pyrolysis of biomass is accompanied by a positive value of the thermal effect in the temperature range of 220–580 °C and varies from 393 to 1475 kJ kg−1 depending on the type of raw materials being processed. The value of this effect makes it possible to organize pyrolysis of biomass in an autothermal regime with preliminary drying: maximum moisture content for straw of 19.9%, wood chips of 10.4%, sawdust of 9.7% and Sukhovskoy peat of 9.5%.

Since the reserves of fossil fuels are gradually exhausting, the biomass inclusion in the energy balance is becoming an urgent issue and a major field for researchers. However, such biomass characteristics as high moisture content, low calorific value, friability, stickiness and others lead to the high operating costs for burning. Thus, biomass pre-processing is required to improve its properties. This work shows the results obtained through the development and substantiation of the parameters of the biomass processing technology in a high-calorie solid fuel for boiler units. Chips from a mixture of Siberian wood (birch, pine, and aspen) and peat of Kandinsky deposit were used as biomass sources. Thermal processing (low-temperature pyrolysis) allows increasing the calorific value of the updated raw materials and obtaining the basis for the binder. Liquid pyrolysis products together with dextrin were used for molding solid composite fuel in the form of pellets and briquettes. These solid fuels had lower heating values of 29.1 MJ/kg (wood chips) and 20.9 MJ/kg (peat), which is superior to most types of fuel briquettes and pellets and comparable to the highest-quality fossil fuels.

The article presents information on local structural nonuniformities in the tube wall metal due to which its individual zones have different susceptibility to corrosion damage processes. The presented information is based on experimental data about the structure of material (microhardness, crystallite size distribution function, and inner structural stresses of the first and second kind depending on the structural flaws density and temperature) obtained using the high-temperature X-radiography method. For a sample made of Grade 20 steel, the temperature range (350–370°C) is experimentally substantiated and determined based on the conditions of relaxing inner structural stresses of the first and second kind in which the crack surface is passivated by oxide film, which prevents the occurrence of stress concentration at the crack edge and crack propagation.

In this paper, we present the results of a numerical investigation into the combustion process in a boiler furnace chamber with swirl burners using design coal (non-coking coal) and substitute coal (coking coal). The paper describes the development of a three-dimensional combustion model for coal burning in a boiler furnace chamber. The utility boiler operates on high-ash non-coking coal with an ash content of 41.94%. Due to the high ash content in the design coal, most of it is released into the atmosphere, which negatively affects the environment and the surrounding area. We suggest that this coal by a different coal with a lower ash content. It was found that during the combustion of substitute coal at the level of burner, the temperature in the entire cross section increases by 200 K, due to more intense fuel burnout at the outer boundary of the burner torches. It is found that the substitute coal may be burned in the boiler furnace chamber and can provide reliable operation if the swirl burner angle is set at 50° for the secondary air and at 45° for the fuel-air mixture.

An evaluation is made of the thermal energy consumed in the heat-technology production of solid composite fuel from low-grade organic raw materials. It is shown that the heat of decomposition of the organic mass and the combustion of the by-products of heat-technology may be sufficient to cover all the energy needs for processing peat, brown coal and wood chips. Producing solid composite fuel from sapropel requires external resources to compensate for part of the heat consumed. Calculations show that it is possible for the thermal processing of raw materials to proceed autothermally due to the heat of decomposition when the moisture content at the reactor inlet is limited: for peat it should be no more than 35%, 54% for brown coal, and 37% for wood chips. The low heat of decomposition of the sapropel organic mass means that its thermal processing cannot proceed autothermally.

This paper presents new approaches to solving problems of forecasting the life of heating surface of boilers, based on an analysis of internal structural stresses of the first and second kind that could affect the intragranular and intergranular strength and reliability of the pipeline in continuous operation by making it work without damage by preventing the disclosure of zone cracks.

The issues and current trends of research in the field of decentralized energy supply for the period up to 2030 were considered. The analysis of the cogeneration market in Russia was done. The questions of gasification and hydrogen technologies as applied to the market of cogeneration plants were elucidated. Promising technologies for autonomous decentralized energy supply and the evaluation of their applicability to small energy were presented.

Results are presented from numerical simulations of mass-transfer and combustion processes in the furnace of a BKZ-420-140-2 boiler using the applied program package FIRE 3D with replacement of the design Ekibastuz coal by Kuznetsk grade D hard coal and Irsha-Borodino grade 2B lignite.

Results from experimental studies of the gas generation process as applied to independent power-generating installations are presented. Circuit solutions for implementing this technology are presented, and recommendations for putting these installations into operation aimed at expanding the use of low-grade kinds of fuel for power generation purposes are given.

In this article are described the prospects of peat and wood using as a raw material for gasification with producing of high potential synthesis gas. It is shown that the low-grade fuel recycling, in particular wood and peat makes a use of this energy sources a possible alternative to the using a more traditional coal and natural gas. The features of low-temperature pyrolysis are analyzed and computer modeling of this process at different conditions is conducted. The temperature influence of recycling to main parameters (calorific value, elementary composition of gaseous components) of produced gas is established.

The article describes computer simulation of the turbulent methane-air combustion in a fire-tube boiler furnace. Computer simulations performed for variants of once-through fire-tube furnace and reversive flame furnace. Options with various twist parameters of the fuel-air jet were examined. The flame structure has been determined computationally, contours of average speed, temperature and concentrations have been acquired. The results of calculations are presented in graphical form. Dependence of construction characteristics on vortex aerodynamic parameters was estimated. Turbulent combustion of natural gas in the reverse flame of fire-tube boiler was studied by means of the ANSYS Fluent 12.1.4 engineering simulation software.

It is common knowledge that theoretical approaches do not allow conducting the objective assessment of the reliability and efficiency of the boiler equipment operation, hence, application of numerical approaches is introduced in the paper. There is the urgent need to assess reliability and efficient operation of boilers at the design stage. The analysis of the temperature level, gas dynamics in the combustion chamber of the boiler and the conclusion about the reliability and efficiency of the designed boiler operation are based on the numerical research.

It is well known fact that appropriate organization of furnace aerodynamics can influence burning stability. Therefore, improving aerodynamic characteristics of the furnace is a main task in elaborating the boiler construction. For this task experimental study of three-dimensional burning flame dynamics should be performed. In this work turbulent combustion of natural gas in fire-tube boiler was simulated by means of the ANSYS Fluent software. The subject of studying was: complex of characteristics with space-time fields of the aerodynamic structure, range and aperture angle of the flame, pressure distribution, turbulent intensity and quite a number of other operation factors. The numerical computation results display the processes within the fire-tube furnace. Inertia of fuel-air jet at the furnace entrance provokes formation of axisymmetric scorching vortices, circulating to the burner slot. The article provides a method for predicting the vortex formation and evaluation of its integral characteristics, including the effect on the aerodynamics and heat transfer processes.

In article the method for predicting the vortex formation in the dead-end furnace is described. Mass and heat balances of environment in the vortex are calculated using the computer simulation with ANSYS Fluent software. Engineering approach for quantitative analysis of singularities in the reversible flame is proposed. Assessment of vortices integral characteristics, including effects on the aerodynamics and heat transfer processes in dead-end furnace, is given.

One of the most important tasks of the automatics and robotics is the design of the feedback regulators for the controlling and stabilization systems. This task contends on the two parts: the design of the regulator structure and the numerical calculation or optimization of its parameters. The paper discusses the both tasks and proposes the adequate decisions for the most difficult examples.

The relevance of the work is caused by necessity of the involving of local low-grade raw materials in the fuel energy balance. The purpose of the work is technical and economical evaluation to implementation possibility of the solid composite fuel production from peat as an example of the Tomsk region. The results of a processing of the low-grade raw materials at certain types from Tomsk region into the solid composite fuel are shown, their competitiveness is evaluated, the process line to production of this fuel is suggested and the economical calculation of the production organization by its basis is made. As a result, the prime cost of solid composite fuel and technical and economical parameters of investments efficiency are determined.

Finite element method was used for simulating the hydrodynamics of fire-tube boiler with the ANSYS Fluent 12.1.4 engineering simulation software. Hydrodynamic structure and volumetric temperature distribution were calculated. The results are presented in graphical form. Complete geometric model of the fire-tube boiler based on boiler drawings was considered. Obtained results are suitable for qualitative analysis of hydrodynamics and singularities identification in fire-tube boiler water shell.

In this paper pulverized combustion of insufficiently investigated low-grade Pavlovskiy coal is simulated using the modern engineering software FIRE 3D. The object of study is a widespread in Russia BKZ–210–140 steam boiler. The results of computer simulation are represented with average temperatures in horizontal sections and oxygen concentration. Curves are plotted for three steam generating capacity loads of the boiler: 100%, 70% and 50%.

Relevance is determined by necessity of utilizing of local low-grade fuels by energy equpment. Most widespread Tomsk oblast (Russian Federation region) low-grade fuels are described and listed. Capability of utilizing is analysed. Mass balances of heat-technology conversion materials and derived products are described. As a result, recycling capability of low-grade fuels in briquette fuel is appraised.