Experimental Study on NOx Generation and Slip NH3 Treatment in a Small Scale Coal-ammonia Co-firing System

Sangin Keel; Minkyu Jeon; Eunsong Lee; Kyoungil Park; Sehyun Baek; Dongkwon Choi

doi:10.15231/jksc.2024.29.3.042

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2024 Vol.29, Issue 3 Preview Page Next Page

Research Article

Experimental Study on NOx Generation and Slip NH₃ Treatment in a Small Scale Coal-ammonia Co-firing System 소형 석탄-암모니아 혼소시스템에서의 NOx 발생 및 slip 암모니아 처리기술에 관한 실험적 연구

30 September 2024. pp. 42-52

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Abstract

Ammonia, along with hydrogen, is a representative CO₂ free energy and co-firing of coal and ammonia is a direct means of suppressing greenhouse gas emissions. As an energy source, excessive generation of NOx, including NO, and the risk of air emissions of ammonia slip are important issues in the use of ammonia fuel. By analyzing the nitrogen oxide emission characteristics from a 5 kW lab. scale co-firing furnaces and deriving a stable treatment function for slip ammonia, we aim to provide basic data necessary for practical design. For this purpose, the NOx generation was checked according to various experimental factors such as ammonia co-firing ratio, air flowrate, ammonia injection point and oxidizer supply technique. There is no doubt that the increase of ammonia co-firing ratio is a factor in the increase of NO emission. However, NO can be stably controlled by combustion engineering methods such as air ratio, multi-stage supply of fuel and oxidizer. And separate supply of ammonia can suppress the generation of NO by inducing effects such as heat load reduction and high-temperature air combustion. Ammonia slip cannot occur in normal operation, but rather slip may occur due to the SCR reductant. In preparation for unexpected ammonia leakage, the installation of an ammonia oxidation catalyst was reviewed.

Keywords

Coal-ammonia co-firing

Stage of air supply

NO emission

Ammonia slip

Ammonia injection

High temperature air combustion

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Information

Publisher :The Korean Society of Combustion
Publisher(Ko) :한국연소학회
Journal Title :Journal of the Korean Society of Combustion
Journal Title(Ko) :한국연소학회지
Volume : 29
No :3
Pages :42-52
Received Date : 2024-09-04
Revised Date : 2024-09-06
Accepted Date : 2024-09-07
DOI :https://doi.org/10.15231/jksc.2024.29.3.042

Journal of the Korean Society of Combustion ISSN:1226-0959(Print) 2466-2089(Online) 한국연소학회지

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