Proposed technological improvement in the recovery of sulfur from the Cienfuegos oil refinery

Abstract

Despite the treatment given to the wastes at Cienfuegos oil refinery, there is a high level of contaminant loads released to the environment. The technology used for the H2S removal or recovery is not sufficient to achieve the gaseous emissions to meet the established regulations. This situation is expected to increase with the refinery expansion that includes new process units. Along with that situation, there are other elements that make the issue even more concerning, such as the high investment cost to purchase new sulphur recovery units; the moderate price for the sulphur sales at the international market and the contaminants restrictions. This research proposes the inclusion of a caustic scrubber packaged tower, for the treatment of the residual gases as a proposal for the technological improvement of the sulphur recovery unit, to allow such process sustainability and achieving the emissions standards. A bibliography review on the major technologies for the sulphur recovery and residual gases treatment is made. Then the caustic scrubber is designed with the use of three types of packages, as to analyze the most viable one. Afterwards an economical assessment is developed to determine which makes the sulphur recovery process more sustainable. This proposal allows obtaining an elementary sulphur recovery of 99, 8 %, the atmospheric emissions are reduced up to 100 mg/Nm3 as SO2 and the population exposure to the gaseous emissions, in general is reduced.