Publications

NSO is an offshore sour gas field in Aceh Production Operations which has been producing since 1999. Post 11 years of plateau rate, the production has declined to a rate below the initial design limit of onshore processing facilities before the expected end of field life. In early 2013, the NSO Turndown Project was initiated to address the low production rate and operational limit while maintaining reliable operations of the plant. The plant modifications focused on two aspects - improving the acid gas removal performance by changing the absorber internals from tray to packing and improving overall process control by downsizing control valves. Each of these aspects had different engineering and execution challenges to overcome during the implementation. The project’s concept selection, design and execution planning was completed in less than two years and utilized a capital efficiency approach from the beginning. The total implementation cost was able to be managed below the initial budgeted amount. Different design strategies played an important role to ensure the success of the project. These included simulation studies, physical low production rate testing and technical evaluations to determine the project scope while also managing residual risks. Keywords: Turndown Limit, Low Production Rate Operation, Absorber Modification, Capital Efficiency, Brownfield Project, Maximizing Asset Value