Mathematical model of a steam boiler as a control plant

Abstract

The article highlights the problems associated with unpredictable outages, uncertainties in fuel supply, unpredictable changes in coal quality, and deterioration of the infrastructure of a thermal coal-fired power plant due to the use of high-ash fuels. Traditional methods of solving these problems lack adaptability and flexibility. The aim of the study was to improve the efficiency of operation of boiler units of thermal coal-fired power plants, which consists in increasing the service life, by improving the models of thermal coal quality management under random perturbations of its composition using automated measurement of abrasive materials in the dust removal system in real time. A simulation model of the influence of coal quality on the erosion wear of heat exchange surfaces of a steam boiler of a thermal coal-fired power plant was developed, consisting of a model of coal transportation and supply, a model of coal quality control, and a model of coal abrasiveness. The models were validated using a computerized flotation test comparison experiment and a one-factor analysis of variance. The experimental results showed that the group mean errors generally do not differ significantly. A method was also developed for controlling the quality of combusted coal when the abrasive composition of the coal batch formed by the supplier is disturbed. The proposed models and methods have the potential to significantly improve the efficiency of thermal coal-fired power plants through the use of computer-integrated systems for managing pipe wear resistance and reducing the need for premature repair and replacement of equipment, as well as ensuring satisfactory quality of fuel and abrasive compositions, namely, fixing the service life of pipes within 5-9 years, as opposed to the unconscious use of highly abrasive fuel, which will cause an urgent shutdown of a thermal coal-fired power plant within a year. This study opens the way to improving the operation of a thermal coal-fired power plant and expands the understanding of the relationship between coal quality and equipment wear. However, further empirical studies with a larger data set would be useful to improve the accuracy and versatility of the model.