Emergency drainage system for power plants and its vertical long axis semi submersible turbine pump solution

The emergency drainage system of the power station is a key system to ensure the safety of the power station equipment and avoid failure shutdown caused by ponding. It mainly deals with the situation of sudden rainstorm ponding in the power station plant, equipment maintenance drainage, underground powerhouse flooding, etc., and protects the core power generation equipment and ensures the safe operation of the power station through rapid pumping and drainage of ponding.
In response to the extreme scenario of complete submergence of underground powerhouses in pumped storage power stations, it is necessary to meet the emergency drainage needs of high flow and high head, and the underground space is narrow and the drainage path is complex, requiring extremely high flexibility and adaptability of drainage equipment.
Divide the entire process of emergency drainage into three stages:
In the initial stage of self discharge of the power station, the diesel generator set reserved by the power station is used for power supply, and a large flow submersible pump is arranged in the access tunnel to discharge the accumulated water within 10 meters above the top of the generator level area, avoiding a sudden drop in pump operating efficiency caused by a large drainage height difference.
Mid stage multi vehicle series drainage stage: Multiple high lift emergency drainage vehicles are used in series to drain the remaining accumulated water on the generator floor and above; For areas with limited space below the generator level, use a floating boat pump to fetch water, temporarily store the accumulated water in the generator level reservoir, and then discharge it through a series drainage system.
In the later stage of water intake, storage, and drainage: Based on the actual situation on site, flexibly allocate drainage equipment, complete the cleaning of remaining accumulated water, and at the same time, isolate the water source during the drainage process to reduce the impact of water leakage from the upper and lower reservoir gates on the drainage progress.
By implementing a phased drainage strategy and reasonably matching drainage equipment at different stages, we not only ensure drainage efficiency but also reduce equipment operating costs, saving valuable time for emergency rescue of pumped storage power stations.
Solution for Vertical Long Axis Pump in Emergency Drainage System of Power Station
1. Equipment selection and adaptation
Conventional factory emergency drainage: Lightweight, high lift vertical long shaft semi submersible turbine pump is selected, and the pump body adopts a compact design, which can be quickly deployed at water accumulation points; The overcurrent components are made of wear-resistant materials and are suitable for complex drainage media containing sediment and oil stains. The head covers 20-100 meters and the flow rate can reach 100-2000m ³/h, meeting the rapid drainage needs of general plant areas.
Drainage of underground powerhouse of pumped storage power station: For the scenario of complete submergence of underground powerhouse, a high flow, high lift vertical long shaft semi submersible turbine pump is selected, combined with a multi vehicle series drainage scheme. The flow rate of a single pump can reach 500-2000m ³/h, and the head can reach up to 15000 meters. Through relay series connection, the water accumulation in areas with large height differences can be pumped out; Alternatively, a floating boat pump can be used in conjunction with a vertical long shaft semi submersible turbine pump. The floating boat pump is used to extract water from narrow spaces, while the vertical long shaft semi submersible turbine pump is responsible for transporting accumulated water to a safe area.
Emergency drainage of coastal/riverside power plants: corrosion-resistant vertical long shaft semi submersible turbine pumps are selected, and the pump body is made of duplex steel or super duplex stainless steel material, which can adapt to water sources containing salt and impurities, avoid corrosion damage, and ensure stable operation in complex water quality environments.
2. Stable operation guarantee
The rotor of the vertical long shaft semi submersible turbine pump adopts a withdrawable design, which can complete the maintenance of core components such as impellers and guide bearings without disassembling the pump body, greatly reducing downtime and ensuring the continuity of emergency drainage.
Equipped with an external cooling and lubrication system to ensure the normal operation of the guide bearing under high temperature and high load conditions; The shaft seal adopts packing sealing, and replaceable shaft sleeves are installed at the shaft seal and guide bearing to reduce the risk of leakage and extend the service life of the vertical long shaft semi submersible turbine pump components.
For special scenarios such as pumped storage power stations, vertical long shaft semi submersible turbine pumps can be paired with diesel generator sets and right angle gearboxes as backup power sources to avoid power outages and drainage interruptions, ensuring normal operation in extreme situations.
3. Intelligent control and rapid response
The vertical long axis semi submersible turbine pump is equipped with an automatic liquid level sensing device, which realizes unmanned automatic start stop. When the accumulated water reaches the set water level, it automatically starts drainage, and when the water level drops to the safe value, it automatically stops, improving emergency drainage efficiency.
Deploy flow, pressure, and liquid level sensors, build an IoT monitoring network, collect real-time data and upload it to the cloud, achieve remote monitoring and data-driven precise scheduling, and timely warn of equipment failures and drainage abnormalities.
For pumped storage power stations, the emergency drainage system can be divided into three stages: initial self discharge, mid-term multi vehicle series connection, and later water intake and storage. Based on the water accumulation range and drainage height difference in different stages, intelligent allocation of vertical long shaft semi submersible turbine pumps and other drainage equipment can be carried out to optimize the drainage path and efficiency.