Acid gas removal is a critical process step in natural gas processing and syngas production for ammonia and other uses. Application of a liquid phase turbocharger to the acid gas removal unit (AGRU) results in significant energy savings and improvement to reliability, availability and maintainability (RAM) of the plant. This paper describes conventional configurations with high-pressure pumps and new configurations utilizing liquid-phase turbochargers. Design of the equipment, process operations and controls, and reliability analysis are included. The results of a RAM study comparing conventional configurations to those incorporating liquid-phase turbochargers in multiple cases are also presented. From the RAM study, it can be concluded that flow sheet configurations that include a liquid phase turbocharger consistently provide lower plant downtime and maintenance costs as compared with conventional flow sheet configurations. This is in addition to the energy savings that result from energy recovery with the application of the liquid phase turbocharger to the AGRU. For the reference plant used in the study, the maintenance cost savings are as great as $2.5M over the 20 year lifetime of the plant and average annual downtime reduction is as much as 19.8 hours.

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