Dosing Control of Urea in Selective Catalytic Reduction (SCR) to enhance the reduction of Nitrogen oxides

Year : 2026 | Volume : 14 | Special Issue 01 | Page : 110 120
    By

    Swetha Bandaru,

  • Jayaprabakar Jayaraman,

  1. PhD, Department of Mechanical Engineering, Sathyabama Institute of Science & technology, Chennai, Tamil Nadu, India
  2. Associate Professor, Department of Mechanical Engineering, Sathyabama Institute of Science & technology, Chennai, Tamil Nadu, India

Abstract

Selective Catalytic Reduction (SCR) is an effective aftertreatment technique designed to comply with rigorous emission criteria established by global regulatory authorities for the elimination of nitrogen oxides from exhaust streams. Since NOx and ammonia reagents are poisonous and an excess of either is therefore very undesired, it poses an intriguing control problem, particularly at high conversion. SCR systems must reduce NOx emissions as much as possible and reduce the possibility of solid deposit fouling, which can harm both the engine and the SCR system. The injection and vaporization of the urea, as well as the diffusion of ammonia in the exhaust gases, have a major impact on both.

Undecomposed urea can cause solid deposits to form, which unpleasantly impact system performance by raising back pressure of engine and lowering overall fuel efficiency. Two SCR models were evaluated: a base and a revised model, both simulated using CFD. The revised design demonstrated a significant 48.8% reduction in accretion rate and better NOx reduction performance, while compared with base model. Incorporate the hybrid mixer to enhance the SCR system efficiency in revised SCR model, compares the two optimized designs of Hybrid mixers. Mixer 1 design is better suitable to reduce the solid deposits and enhance the SCR system performance. The mixer 1 design achieves 4% reduction in accretion rate compared with mixer2 design of hybrid mixer in revised SCR model.

Keywords: Solid Deposits, Selective Catalytic Reduction, Mixer design, After treatment system, NOx reduction, optimized design.Solid Deposits, Selective Catalytic Reduction, Mixer design, After treatment system, NOx reduction, optimized design.

[This article belongs to Special Issue under section in Journal of Polymer & Composites (jopc)]

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How to cite this article:
Swetha Bandaru, Jayaprabakar Jayaraman. Dosing Control of Urea in Selective Catalytic Reduction (SCR) to enhance the reduction of Nitrogen oxides. Journal of Polymer & Composites. 2025; 14(01):110-120.
How to cite this URL:
Swetha Bandaru, Jayaprabakar Jayaraman. Dosing Control of Urea in Selective Catalytic Reduction (SCR) to enhance the reduction of Nitrogen oxides. Journal of Polymer & Composites. 2025; 14(01):110-120. Available from: https://journals.stmjournals.com/jopc/article=2025/view=217020


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Special Issue Subscription Original Research
Volume 14
Special Issue 01
Received 10/06/2025
Accepted 02/07/2025
Published 17/07/2025
Publication Time 37 Days
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