Ammonia distribution characteristics at the selective catalytic reduction reactor inlet with linear partitioning

Analyzing the uniformity of ammonia distribution at the inlet of selective catalytic reduction reactors is crucial for enhancing denitrification efficiency. To minimize ammonia slip while ensuring effective denitrification, this study examines ammonia flow characteristics in the SCR system under various zoning schemes. In scheme I, zones A1, A2, A3, and A4 predominantly influence the left, center, center-right, and far-right regions of the reactor inlet. As ammonia velocity increases from 4 m/s to 12 m/s, the concentration significantly increases, with Zone A4's peak concentration rising from 0.0099 mol/m³ to 0.03 mol/m³. Similarly, increasing the ammonia spraying concentration from 1% to 9% enlarges the affected regions, particularly in Zone A1, where the impacted area expands from 1/3 to 1/2. Scheme II demonstrates a broader and more uniform distribution, which reduces localized concentrations but compromises precision in specific regions. This is of significant importance in reducing nitrogen oxide emissions in coal-fired power plants.