Improving Sulphur Plant Reliability and Efficiency

ADNOC LNG on Das Island facility consists of three process trains. Each train contains one Sulphur Recovery Unit (SRU) which comprises a three-stage Claus unit followed by a SUPERCLAUS® unit. In the past 5 years, average Reliability of these SRUs is 85.7%, much below 98% of the LNG group benchmark value. The calculated Sulphur recovery efficiency in Clause mode is between 92% to 96% which is well below the target value of 97.5%. The SRU reliability and efficiency continue to have a negative impact on Sulphur production loss as well as flaring and emissions. This paper describes corrective actions taken by ADNOC LNG to address these issues in order to improve SRU reliability and efficiency and to minimize production losses and flaring. The implementation of these corrective actions has resulted in 8% improvement on SRU reliability. Sulphur recovery efficiency under Clause mode increased by 3.1%, leading to a significant reduction on flaring and emission, as well as increase on Sulphur production.