Utilization of Exhausted Oxygen from Nitrogen Plant to Improve Sulfur Recovery Unit and Reduce Emissions—Case Study

The main function of the SRUs is to treat a sour gas from the gas processing plant, which contains CO₂, H₂S, and H₂O. Mellitah complex is the case study where two nitrogen plants were designed to process 3500 nm³/h of air for each train to produce pure N₂; the idea of this work is the utilization of exhausted oxygen via nitrogen plants to improve SRUs performance, by simulating (steady state) the existing operating parameters using ProMax® software to compare between the performance of SRU with and without enriched oxygen. Results showed an improvement of the current situation of SRU efficiency in Mellitah complex, by using the exhausted oxygen from nitrogen plants. The enrichment of oxygen can increase the capacity of SRU in Mellitah complex up to 40%, and this enhancement can also increase the productivity of the unit itself. Furthermore, it decreases the tail gas from Claus which contains H₂S and SO₂. Finally, the enrichment can be implemented in Euro Mid region to improve the air quality.