The increasing production of spent acid from petroleum refineries and chemical plants, as well as higher sulfuric acid demand in the broader market, continues to stretch the processing capabilities of sulfuric acid regeneration (SAR) plants. These trends affect captive as well as merchant sulfuric acid regenerators. Oxygen enrichment of the combustion air in a SAR plant offers a means of significantly increasing the acid regeneration capacity of the plant. This capacity increase can be achieved in an economic, reliable, flexible and safe manner and at a fraction of the cost of a major plant retrofit. Additional benefits of this technology include the ability to maintain emissions at acceptable levels and stay within environmental conformance at increased production levels. In most cases oxygen enrichment can be implemented without having to shutdown the SAR plant. For bulk liquid delivery, normal installation of an oxygen storage and delivery system is a few days.