The goal of the research is to develop the guidelines for increasing the capacity of the operating 300 MW power-generating units by using the allowances assumed at the design computations and manufacture of the power-generating equipment, while preserving its reliability criteria and performance efficiency. The capacity of the operating power-generating units is increased in three stages.
Boiler units at Ukrainian thermal power plants need to be modernized or replaced in the short run, as this is important for the national energy security. The authors determined one of possible ways to improve the efficiency indicators of coal-fired boiler units and power generating units as a whole up to the values exceeding the design ones. This variant of improvement consists in abandoning the technology of using flue gas as drying agent in pulverized coal systems and replacing it with direct discharge of the gas flow into the boiler furnace.
Reconditioning of the TP-100А boiler can be implemented via a number of engineering solutions, including a complete replacement of the heating surface of the primary and secondary steam superheating circuits, boiler drum replacement, pulverized coal system closing, installation of gas-tight water walls; replacement of all the tanks of the water economizer, replacement of all the tanks of the tubular air heater (TAH); replacement of the check and control valves, replacement of all the steam pipelines in a boiler room.
The paper deals with the methods for defining the composition of the coal mixture burnt in boilers at combined heat and power plants. Indirect methods for defining the proportions of the two grades of coal in the mixture based on the available information on the quality characteristics of the coal are proposed. According to the first method the coal mixture composition is determined based on the values of volatile substances content in the combustible mass of the coal mixture and of each grade of coal making up the mixture.