<p>Sulphuric acid is the most widely produced bulk chemical in the world, with a continuously increasing demand over the years. Driven by stringent regulations, the sulphuric acid production process has seen broader implementation to restrain the release of sulphur dioxide (SO₂) emissions into the atmosphere due to the associated health concerns and environmental impact. The sulphuric acid plant industry has reached a high level of maturity and has consistently pursued advancements in the adopted technologies, but the currently used double contact double absorption (DCDA) process still vents SO₂ to the atmosphere. The present work introduces a novel approach to enhance SO₂ removal using oxygen-enriched air. Aspen Plus software was used to model and simulate the DCDA process to assess the plant’s performance using rate-based reactor models to minimize overall SO₂ emissions by manipulating dioxygen (O₂) quantities in the combustion air. The objective was to evaluate the extent of SO₂ emission reduction and to determine the optimal oxygen concentration in the combustion air that maximizes environmental performance while limiting the hazards associated with oxygen enrichment. Obtained results demonstrated a significantly enhanced overall SO₂-to-H₂SO₄ conversion efficiency, reaching 99.99% across the entire DCDA process, which resulted in SO₂ emissions substantially lower than those achieved by the current Best Available Techniques. Simulation results were verified by a well-established graphical method, and its findings confirmed the improvement levels predicted by Aspen Plus.</p>