Spray Nozzle / Distribution Tray

The spray nozzle/distribution tray is a critical component of a deaerator, typically located in the deaeration section. Its primary function is to receive incoming feedwater and atomize it into a fine mist or spray, ensuring uniform distribution over the heating zone (steam-filled area). This maximizes the surface area of the water droplets, promoting efficient heat transfer from the steam and the release of dissolved gases, primarily oxygen and carbon dioxide, which are then vented from the system.

In operation, pressurized feedwater is forced through the spray nozzles, creating a conical spray pattern of fine droplets. These droplets fall through a chamber filled with steam (the heating zone). The large surface area of the droplets allows for rapid heating to saturation temperature, which drastically reduces the solubility of dissolved gases. The released gases are carried upward with the excess steam and vented out of the deaerator.

This component is available in materials such as stainless steel (e.g., 304, 316) or carbon steel, with the choice depending on the water chemistry and operating conditions. Key parameters include nominal diameter (DN50–DN200), flow rate (5–50 m³/h per nozzle at 0.1 MPa differential), spray angle (60–120°), operating pressure (0.1–0.6 MPa), operating temperature (20–120°C), material grade (304/316L), surface finish (Ra 0.8–1.6 μm), weight (2–15 kg), and connection type (flanged for DN≥100, threaded for smaller). These values are reference ranges and must be confirmed for the specific model and application.

When selecting or verifying a spray nozzle/distribution tray, consider the required flow capacity, spray coverage, and compatibility with the feedwater chemistry. Verify the nominal diameter matches the pipe size, the flow rate meets system demands, and the spray angle provides uniform coverage. Confirm the operating pressure and temperature are within the specified limits, and select the appropriate material and surface finish to resist corrosion and scaling. Check the connection type to ensure compatibility with existing piping. Always consult the legal manufacturer or supplier for model-specific values and standards, as the listed standards (e.g., ISO 6708, ASTM A240, ISO 1302, GB/T 9119) are procurement references, not proof of certification or compliance.

Pressurized feedwater is forced through the spray nozzles, creating a conical spray pattern of fine droplets. These droplets fall through a chamber filled with steam (the heating zone). The large surface area of the droplets allows for rapid heating to saturation temperature, which drastically reduces the solubility of dissolved gases. The released gases are carried upward with the excess steam and vented out of the deaerator.