Techno-Economic Design and Optimization of Ngl PLANT: Retrofit STUDY

ABSTRACT

This paper proposes an approach that combines a process simulation model with Design of Experiments (DOE) and Surface Response Methodology (SRM) tools, for retrofit design. A case study considered in the study is a Natural Gas Liquid (NGL) Recovery Plant, and a steady-state model of the plant is set up for evaluating economic and environmental impacts arising from debottlenecking or process improvements made to the plant. Aspen Plus TM® is used for simulation, of which results agrees well with the measured data. The sensitivity analysis has been first performed and the results obtained have been taken into account to build the optimization problem in which distributed control system data and operators experience are also considered. Optimization has been performed by varying operating conditions (continuous variables ) of the NGL plant, as well as by embedding different structural changes (discrete variables ), leading to improvement of profitability. The optimal operating scenarios have been selected with promising structural changes. The proposed approach can provide deep understanding of system interactions, which allows substantial improvement of process performance.