Many plants are facing stricter NOx emission reduction limitations from boiler stack gases in the near future. Often, NOx emissions must be reduced by more than 50% from current levels.
Jansen’s Approach to Solving NOx Emissions Reduction Issues
- Understanding the customer’s goals
- Understanding the local environmental permitting constraints.
- Evaluating the current boiler operation to:
a. Determine current NOx creation mechanism
b. Analyze the physical arrangement of the combustion system; size of furnace, location of existing burners and air supply
c. Determine operating strategy/control, fuel splits, load variability
d. Establish fuel properties
- Perform Computational Fluid Dynamics (CFD) modeling to predict effectiveness of types of solutions.
- Evaluating types or combination of NOx reduction solutions for most viable and cost effective solutions. Determine capital cost and operating costs as well as “side effects” of proposed solutions.
- Providing operating recommendations and hardware alterations that best meet the customers’ goals. Where appropriate, possible solutions may include:
• Staged combustion/overfire air
• Flue gas recirculation (FGR)
• Low excess air
• Low NOx burners
• Fuel rich secondary combustion (reburning)
• Automatic combustion controls
• Urea/ammonia injection (SNCR)
- Design and supply specific NOx reduction technology and equipment.