The vacuum extraction system is a critical component of the direct air-cooling system; its function is to establish and maintain low back pressure for the steam turbine unit and a vacuum within the condenser. During unit startup, it removes accumulated air from various steam and water piping systems and equipment, thereby accelerating the startup process.
The ability to maintain an optimal vacuum serves as a key performance indicator for the vacuum extraction equipment and significantly impacts both the safety and economic efficiency of the steam turbine. During operation, any lack of airtightness in the vacuum system allows air to leak in, thereby degrading the vacuum. This rise in air partial pressure-combined with the fact that air solubility is directly proportional to partial pressure-leads to increased air dissolution in the water, resulting in a higher oxygen content in the condensate.
