Process Design of Natural Gas Liquid Recovery Processes

Abstract

A new optimization framework for the design of natural gas liquid (NGL) recovery processes was developed to effectively investigate design complexities associated with complex column arrangements and heat and power recoveries. Design interactions were evaluated in a holistic manner, and optimal operating conditions were determined for the recovery process, leading to efficient energy use and recovery. Rigorous modeling of the NGL recovery process was performed using a process simulator combined with an optimization solver to obtain optimal solutions. The candidates for the optimal conditions of the decision variables were generated by the solver, and were updated until optimal solutions were obtained, while an objective function was evaluated with the aid of the process simulator. Process integration methodology was applied to assess the true potential of heat recovery and improve energy recovery for the entire process within the proposed optimization procedure. A case study was presented that demonstrated how heat and power recovery issues could be collectively and systematically considered with the design of separation and recovery arrangements, which clearly showed the usefulness and applicability of the design and optimization method developed in this work.