In the present paper, the furnace chamber of the BKZ-160 boiler of Almaty TPP-3 (Kazakhstan) has been calculated. The thermal characteristics of the process were studied in the form of the distribution of temperature fields and chemical energy, and the aerodynamics of the combustion chamber was also calculated. The type of fuel, its elementary and fractional composition, exerts the greatest influence on the course of heat-mass exchange processes and aerodynamics. The computational experiment was carried out with two models of particle size distribution: a polydisperse fuel flame (the particle diameter varies from 10 to 120 μm) and monodisperse fuel flame (particle size identical and equal to d p = 60 μm). Based on the results of the computational experiments, the main regularities in the distribution of heat fluxes in the combustion chamber volume and flow aerodynamics were obtained. It is shown that the greatest thermal load falls on the central region of the walls of the combustion chamber and the location of the burner devices, which is typical for both mono-and polydisperse fuel flames. The temperature data obtained as a result of the computational experiment showed better convergence with the empirical data obtained directly at TPP-3. Aerodynamics of the flow for the two selected models of particle size distribution has insignificant differences, but how they affect other characteristics of the process is one of the following tasks in view of the authors. It should be noted that the calculation of the polydisperse fuel flame takes much more calculation time.

In the present paper, a study of furnace processes in the combustion chamber of the real energy boiler BKZ-160 of Almaty TPP-3 (Kazakhstan) using three-dimensional modeling methods has been carried out. Calculations of the combustion chamber for flame combustion of pulverized coal have been performed. The main purpose of this paper was to study the effect of fractional fuel composition on the concentration characteristics of the combustion process. Numerical simulation was carried out with two models of coal particle size distribution: monodisperse fuel flame (coal particle size identical and equal to 60 μm) and a polydisperse fuel flame (coal particle diameter varies from 10 to 120 μm). The polydisperse distribution corresponds to the fractional distribution (percentage of total coal particles) calculated for this boiler: the first fraction-10% with d p = 10 μm; 20% with d p = 30 μm; 40% with d p = 60 μm; 20% with d p = 100 μm; 10% with d p = 120 μm. The numerical simulation results of the influence of the pulverized coal particle size composition on concentration characteristics of combustion process are presented. The distributions of oxidizer (oxygen) and combustion products (NO, CO, CO 2) are shown. Areas with the greatest concentration of gas products of burning are determined, regularities of formation of products and their concentration at the exit of fire chamber are also determined. The effect of fractional fuel composition on the obtained characteristics is sufficiently large, the empirical data obtained directly at TPP-3 show better convergence with the result of the computational experiment that confirms simultaneously the adequacy of the used physical and mathematical statement of the problem, as well as the validity of using the model of polyfractional distribution.

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Abstract. The emissions of harmful substances such as sulphur and nitrogen oxides from thermal power plants are major source of adverse impact on the environment. In this regard, it remains be urgent the deeper studying of the solid fuel combustion processes. In this paper, two global schemes of formation and destruction of harmful nitrogen compounds NOx studied during combustion of low-grade Kazakh coal in a real industrial boiler BKZ-75.

Computational fluid dynamics (CFD) becomes more and more reliable tool to analyze the furnace operation under different conditions. This paper provides and overview of the current possibilities of 3D-Finite Volume tool FLOREAN developed at the Institute for Heat and Fuel technology TU Braunschweig. This program is used for simulations of combustion processes in industrial furnaces. FLOREAN has been applied for the calculation of a furnace chamber of Aksu power station fired with low grade coal of Ekibastuz (Kazakhstan). Distributions of different parameters such as temperature, fluid flow properties (velocities, pollutant substances such as CO, NOx) etc. are simulated. These simulations can be used to design furnaces, optimize furnace operation and minimize pollutant emissions.

Abstract. The main purpose of research is to predict the influence of different water content in coal on overall furnace operation and formation of combustion products. Numerical experiments was carried out on the basis of three-dimensional equations of convective heat and mass transfer, taking into account the heat propagation, heat radiation, chemical reactions and multiphase structure of the medium. This paper presents the results of numerical modeling of high-ash Ekibastuz coal burning in combustion chamber of Kazakhstan Power Plant. Increase of water content in coal leads to reduce the amount of harmful emissions and decrease the average temperature in the combustion chamber.