The increase of operation efficiency of within Condensing Power Plant of 4 GW power capacity operated in hard coal use.
Students Name: Romaniv Roman Yaroslavovych
Qualification Level: magister
Speciality: Heat and Power Engineering
Institute: Institute of Power Engineering and Control Systems
Mode of Study: full
Academic Year: 2023-2024 н.р.
Language of Defence: англійська
Abstract: Romaniv R.Y., Yurasova O.H. (supervisor). The increasing the efficiency of the 4 GW CPP operating on hard coal. Master’s thesis. – Lviv Polytechnic National University, Lviv, 2023. Condensation power plants (CPP) are called thermal power plants designed only for the production of electricity. The main feature of condensing power stations is that they provide the conditions for the most complete conversion of steam energy produced in the boiler, by expanding it as much as possible in the working cylinders of the turbine into the mechanical energy of rotation of the rotor-turbogenerator, and then into electrical energy. To ensure the maximum complete conversion of steam energy, its exhaust from the turbine is carried out into special heat exchangers, in which the condensation of spent steam takes place and the minimum pressure (vacuum) for specific temperature conditions is maintained. Such heat exchangers are called condensers. The latent heat of vaporization released during condensation is discharged through the external circulation circuit into the environment (water body or atmosphere) and is irreversibly lost. The share of this heat in the overall balance of a steam power plant reaches 60–65%, which causes a relatively low thermal efficiency of condensing power plants, mostly not exceeding 40%. Therefore, it is proposed to modernize the low pressure cylinder (LPC) of the standard turbine by replacing the splitter and the first two along the course of the pair of axial stages in each stream with a two-flow radial-axial stage of the meander type, as well as installing a stage with double exhaust into the condenser as the last stage. This design of the LPC turbine allows reducing the number of LPC s to one, reducing the dimensions of the turbine, as a result of which the metal capacity decreases, making it more compact, and increasing the efficiency of the turbo installation. All this determines the relevance of the project topic. The object of the study is a condensing power plant with a capacity of 4 GW. The subject of the study is the project of a condensing power plant with a capacity of 4 GW operating on hard coal. Purpose and tasks of research. The purpose of the work is to increase the efficiency of the 4 GW power plant operating on hard coal. To achieve the goal, it was necessary to complete the following tasks: - to develop a project of a 4 GW coal-fired CPP; - carry out the modernization of the LPC of the standard turbine; - carry out calculations of the main equipment. The master’s thesis is devoted to increasing the efficiency of the 4 GW power plant operating on hard coal. The LPC of the standard turbine was modernized by replacing the splitter and the first two along the course of a pair of axial stages in each stream with a two-flow radial-axial meander-type stage, as well as installing a stage with double exhaust into the condenser as the last stage. This design of the LPC turbine allows reducing the number of LPCs to one, reducing the dimensions of the turbine, as a result of which the metal capacity decreases, making it more compact, and increasing the efficiency of the turbo installation. All this determines the relevance of the project topic. A fundamentally new design of the LPC with a radial-axial stage instead of a flow separator is proposed, and as the last stage of the LPC - a stage with a double exhaust into the condenser. This scheme allows you to reduce the number of LPCs to one, as well as the total number of stages in it. To ensure the maximum complete conversion of steam energy, its exhaust from the turbine is carried out into special heat exchangers, in which the condensation of spent steam takes place and the minimum pressure (vacuum) for specific temperature conditions is maintained. Such heat exchangers are called condensers. The latent heat of vaporization released during condensation is discharged through the external circulation circuit into the environment (water body or atmosphere) and is irreversibly lost. The share of this heat in the overall balance of a steam power plant reaches 60–65%, which causes a relatively low thermal efficiency of condensing power plants, mostly not exceeding 40%. In the economy section, economic indicators are calculated that show the economic efficiency of the projected condensing power plant with a capacity of 4 GW. A description of the control and measuring devices of the turbine unit, their purpose and automatic protection of the turbine, which prevent the development of accidents in the event of an emergency situation on the turbine unit, is given. Automatic protection commands have priority over all other automatic or manual control commands. Key words: condensing power plant, design, hard coal, low pressure cylinder, condenser.