Power Industry

Vacuum systems for electric power generation

The main applications of vacuum pumps in the power industry include: condenser vacuuming, vacuum water suction, flue gas desulfurization, fly ash conveying, turbine seal pipe exhaust, vacuum degassing, and geothermal gas extraction.

In the steam power cycle of thermal power plants or nuclear power plants, the exhaust steam from the turbine needs to be condensed into water in the condenser. Vacuum pumps are used to remove non-condensable gases (such as air) and small amounts of leaked steam from the condenser shell side to establish and maintain a high vacuum environment. This significantly reduces the condensation temperature (back pressure) of the exhaust steam, increases the enthalpy drop of the steam, thereby improving the thermal efficiency and output of the turbine, and is one of the key links in energy saving and efficiency improvement in power plants.

In the water treatment system or hydraulic ash removal system of power plants, the pump casing and suction pipeline need to be filled with water before the centrifugal pump starts. Vacuum pumps are used to evacuate the pump body, creating negative pressure, thereby lifting water from the water source and filling the pipeline, achieving automatic priming of the pump, ensuring the normal start and stable operation of the water pump, and avoiding the tedious and unreliable manual priming process.

In wet flue gas desulfurization systems, flue gas containing sulfur dioxide needs to be extracted from the absorption tower for treatment. Vacuum pumps (commonly liquid ring type) can provide auxiliary power for the booster fan of the desulfurization system, overcoming system resistance and ensuring that the flue gas is smoothly drawn into and flows through the absorption tower, demister, and other equipment, effectively completing the desulfurization reaction and meeting environmental emission requirements.

In coal-fired power plants, the fly ash generated by boiler combustion needs to be transported to the ash storage silo through a pipeline system. Vacuum pumps are often used in negative pressure pneumatic ash conveying systems. They create a vacuum at the beginning of the conveying pipeline, sucking the mixture of fly ash and air into the pipeline and transporting it to the destination. This system has good sealing performance, effectively preventing dust leakage and achieving clean and efficient fly ash collection and transfer.

This application covers gas exhaust in multiple auxiliary systems of power plants. For example, removing air from the boiler drum or superheater before boiler startup; vacuuming the deaerator in the condensate polishing system to remove dissolved oxygen; or providing a vacuum source for various experimental and testing equipment that require a negative pressure environment. Vacuum exhaust is an important means of ensuring equipment performance and preventing oxidative corrosion.

In the field of geothermal power generation, vacuum pumps play a special role. After the geothermal fluid (a mixture of hot water and steam) is extracted from the geothermal well and the steam is separated in a separator to drive the turbine, non-condensable gases (such as carbon dioxide, hydrogen sulfide, etc.) may still be present in the system. Vacuum pumps are used to forcibly remove these harmful gases from the condenser or gas exhaust system, maintaining a high vacuum in the system and collecting and treating the harmful gases, ensuring the efficient, safe, and environmentally friendly operation of the geothermal power plant.