What is molten salt submerged pump
RY-type molten salt pump is a single-stage, single-suction cantilever submerged pump, which is suitable for conveying molten salt (KNO3 53%, Na2NO240%, NaNO37%) with high temperature (temperature ≤ 600 ℃), for industrial departments such as ionic membrane caustic soda, alumina, etc., and also for conveying liquid with other high-temperature special media. RY-type molten salt pump is a series of molten salt pump products independently developed on the basis of years of production of high-temperature submerged pump and molten salt submerged pump, referring to the structure of similar foreign products. It is a special high-temperature pump for molten salt circulation system or molten salt transportation.
The structure of molten salt pump mainly consists of power system, transmission system and conveying system. The power system mainly includes motor and motor support. It is the power source of molten salt pump. The transmission system includes the main shaft and bearing bracket, which is responsible for completing the power transmission. The high-speed operation of the motor is converted into the operation of the impeller to generate the power to transport high-temperature molten salt. The conveying system is mainly composed of conveying pipes, which is used to complete the transportation of high-temperature molten salt.
Before determining the type selection of molten salt pump, the composition of molten salt used should be analyzed first. Including the type of molten salt, service temperature, melting point, gasification point, etc. On the whole, the material of the pump should be resistant to high temperature and corrosion, and its strength and service life should be considered. The gas released by molten salt decomposition at high temperature is more corrosive. Taking the common binary molten salt as an example, the operating temperature of the trough molten salt power station and the tower molten salt power station are different. The operating temperature of the trough molten salt heat storage system is between 220 ℃ and 400 ℃. According to this temperature, 304 and 316 stainless steel can be selected as the material of the molten salt pump; For tower type molten salt power station, the working temperature of molten salt is between 220 ℃ and 550 ℃, and 316, 347 stainless steel or 718 chromium-nickel alloy steel that is more resistant to high temperature and corrosion is required.
The high-speed flow of molten salt will also cause rapid corrosion of the impeller blades of the molten salt pump. The corrosion damage rate is proportional to the medium flow rate. The higher the flow rate, the faster the corrosion rate. Therefore, the flow rate of molten salt should be properly controlled within the safe range.