A steam desuperheater is used for reducing the temperature of superheated to steam close its saturation point, where thermal efficiency is highest. This is performed by injecting spray water into the steam flow. Spray water flow is controlled by an external water control valve and injected perpendicular to the steam flow using a series of spring-loaded spray water atomizing nozzles. The steam pipe is protected from thermal stresses by a welded liner which also acts as a flow profiler, increasing the relative steam velocity near the nozzles and improving evaporation. The number of nozzles are chosen based on the steam pipe diameter, in order to improve the spread of injected water over its cross section, and the nozzle springs are chosen / preloaded to avoid flashing in the nozzle opening.
Key features
- Very high reliability due to being able to handle thermal cycling
- Flow profiling liner as standard
- Designed to handle large spray water flow
- Nozzles resistant to flashing
- Water atomization pressure is maintained at each nozzle at any flow condition
- Even distribution of spray water in the steam pipe
- Negligable pressure drop in the steam line