Cost Effective Solution for Replacing Amine Columns

Abstract

Amine Regenerator column is in operation since 1980 and severe internal corrosion / erosion observed since 2000 and subsequent local shell course replacement in 2015 and 2017 were done. Therefore, to avoid frequent maintenance and repair cost and to ensure long-term measure of integrity and availability of the equipment, it was concluded to replace the existing CS column with enhanced metallurgy The convectional approach of replacing the full column with CS +SS 3mm clad material which typically take around 12 month schedule for fabrication activities in dedicated shutdown in 2021. In addition, this replacement was planned to include replacement of full internals of amine column, existing foundation, pipe support and platform. Moreover, the execution strategy planned to be through FEED/EPC. However, looking for enhanced metallurgy and studying the local market stock of raw material and manufacturer have a big role to carry out the replacement job in planned shutdown in 2020 and within planned budget. The solution in going with solid SS vessel instead of clad will not only improve integrity but also will lead to enhanced schedule into 6.5 months and it is the most commercially attractive option. Moreover, going with solid SS material will reduce the fabrication time and avoid the issues associated with cladded materials and the requirements of the NDT due to welding job. In addition, it was planned to replace partially the column internals after reviewing the inspection history instead of replacing them fully. Further, the column and column internals procurement were accomplish with in in-house resources. The installation job of column, column internals, and foundation carried out within available planed June 2020 shutdown. The development of execution strategy/in-house engineering led to avoid of 35-days unit 2021 shutdown. Also, achieving direct cost saving of USD 1 million in procurement of Column and Column Internal from the planned budget. Further, the availability of SS solid material in UAE ex-stock and local manufacturer, were considered in minimizing the transportation and delivery schedule. The column replacement was the solution to tackle the repetitive corrosion/ thickness loss failures in the vessel. The way forward of replacing full column with SS solid material will improve integrity, enhanced delivery schedule, commercially it is an attractive option and has direct support to ADNOC ICV strategy. Hence, this job will avoid the dedicated 35 days in 2021 shutdown and accordingly the revenues losses of OPCOs shutdown