CORROSION PERFORMANCE OF COMMERCIALLY PURE TITANIUM EXCHANGER TUBES IN ACID GAS REMOVAL UNITS; OPERATIONAL EXPERIENCE

摘要

Harsh operating conditions prevailing in acid gas sweetening plants necessitate correct choice of materials and corrosion mitigating measures. In particular, carbonate cooler units impose significant challenges to an endured processing of harsh processing fluids represented by a combination of elevated temperatures, corrosive fluids, fluid dynamics and operating conditions. While, commercially pure titanium has generally provided a satisfactory performance in acid gas sweetening plants, a number of failures were experienced as a result of wall loss and internal scaling. This paper captures operational performance of Ti Grade 2 exchanger tubes and recaps degradation processes that led to the occurrence of these failures. It highlights failure mechanisms and necessary measures to minimising their future occurrence. Potential solutions are described including operational and design modifications and materials upgrade. The materials upgrade is developed based on a suitability rating taking into consideration several key parameters including corrosion performance, track record, strength ratio, cost comparison and availability. The paper has paved the way for sustaining trouble free operations in acid gas removal units.