Industrial spray application guide
SCR and SNCR Reagent Injection Nozzles
SCR SNCR injection nozzles atomize approved reagent into flue gas where droplet size, trajectory and distribution must match the operating temperature window. SCR and SNCR injection nozzles atomize and distribute reagent into a flue-gas stream for NOx-control systems. Mixing, temperature window, residence time and reagent chemistry determine system performance.
Engineering focus
What the spray system must accomplish
Poor distribution can create untreated zones or reagent slip. Droplet evaporation, wall impingement, gas velocity, temperature profile and lance placement require system-level modeling or testing.
Inputs required before selection
- Process type, reagent, concentration and flow range
- Gas temperature, velocity, composition and NOx profile
- Available residence distance and injection grid geometry
- Atomizing medium, materials, maintenance and controls
- Connection, installation space and maintenance access
- Required documentation, test method and acceptance criteria
Comparison
Practical nozzle starting points
| Nozzle approach | Useful starting condition | What to verify |
|---|---|---|
| Twin-fluid nozzle lance | Fine atomization and adjustable momentum | Requires atomizing air/steam and tuned ratios |
| Hydraulic pressure nozzle | Simpler reagent injection without atomizing gas | Check droplet size and turndown |
| Multi-nozzle injection grid | Large ducts or nonuniform gas profiles | Requires distribution analysis and balancing |
Review method
How to move from requirement to a defensible selection
- Define the process envelope. Record normal, minimum, maximum and upset conditions rather than one nominal point.
- Choose the spray function. State whether the job is coverage, impact, atomization, evaporation, gas–liquid contact, washing or cooling.
- Check distribution in the real geometry. Review spacing, overlap, obstructions, wall contact, drainage and access.
- Validate materials and maintenance. Consider corrosion, erosion, solids, filtration, cleaning and replacement intervals.
- Set an acceptance test. Use an observable measure such as coverage, flow, temperature profile, pressure, droplet data or process result.
Related applications
Technical references
These sources define process or system context. Product suitability still requires project-specific engineering review.
- U.S. EPA — Selective catalytic and non-catalytic reduction fact sheets
- Lechler — Nozzle lances for SCR/SNCR applications
Last technical review: 31 July 2026
RFQ checklist
Send the operating data, not just a nozzle name
Include the application, fluid, flow, pressure, temperature, spray distance, connection, material preference, drawings and acceptance criteria.
SCR/SNCR Injection Nozzle Selection Check
For SCR SNCR injection nozzles, confirm reagent concentration, gas temperature profile, available mixing distance, target reduction, allowable ammonia slip and wall-wetting limits. SCR SNCR injection nozzles must also be reviewed for droplet size, spray angle, lance position, turndown, compressed-air demand, materials and maintenance access.