Specific Features of Calculation of Medium-Power Wood Chips Water Heating Boilers

The paper studies the performance of a 1800 kW water heating boiler for burning wood chips. Literature information on methods for calculating medium-power water heating boilers using solid biofuels is analyzed. It is noted that the introduction of solid biofuel boilers will contribute to the replacement of fossil fuels, the renewal of technological parks of existing equipment, the development of the production of new equipment, and its installation and maintenance activities. It is shown that in modern literature there is very little information on the methods for calculating medium-power boilers on solid biomass, and the available information is not systematized and not generalized. It is shown that in the Normative Method for Thermal Calculation of Boiler Units there is no information on the features of calculating boilers on solid biomass, namely: there are no recommendations for calculating heat exchange in the boiler furnace, in a heat exchanger with intensified heat exchange for boilers on solid biomass. The influence of the ash removal fraction, excess air coefficient, wood moisture, and Aash coefficient on the temperature of flue gases at the boiler outlet and compared with operating data were investigated. The features of calculating a wood chip water heating boiler were proposed. The calculated gas temperature indicators at the boiler outlet were compared with operating data. It was shown that there is little information in the literature on the recommended values of the thermal stress of the combustion mirror for modern methods of burning solid plant biomass. It was indicated that the study of solid biomass combustion processes and the development of calculation methods, the formation of a database on the coefficients required for calculation are quite relevant tasks. It was indicated that at this stage of research, the method for calculating heat transfer in the boiler furnace, given in the normative method of thermal calculation of boiler units, should be used for calculating medium-power water heating boilers. Despite the simplifications incorporated in the mathematical model, the results of calculations and operating data do not differ significantly.