Question
-
Considering more stringent NOx reduction requirements in the refining and petrochemical industry, what are the optimal strategies for reducing NOx emissions from process heaters and SMR/PSA heaters?
Jul-2022
Answers
-
Hervé Lavieu, Heurtey Petrochem Solutions, herve.lavieu@heurtey.net
There are several aspects to be considered:
- At the pre-combustion level, the solution of ‘fuel switch’, mostly meaning fuel oil (FO) to fuel gas (FG), appears to be beneficial. The switch from FO firing to FG firing will reduce the flame temperature and, as a result, reduce the NOx thermally generated. This switch will also be beneficial since, unlike the FO, the FG combustion will not contain organo-nitrogen compounds and chemically formed NOx will therefore be eradicated.- At the combustion level, accurate control of excess air will also reduce NOx formation. At the post-combustion level, the installation of a DeNOx system (SCR) remains the more efficient solution for NOx reduction. SCR is a post-combustion method dedicated to converting NOx into Nâ‚‚ and Hâ‚‚O by means of reaction with ammonia (NH3) in the presence of catalyst. SCR systems can achieve a reduction of up to 95+% of NOx in the flue gas stream.
Jul-2022
SPONSORS