Development of a Novel Optimization Model for Feasibility Study: A Case Study of Determining Optimum Configuration of Petrochemical Downstream Process

Research Interests: Process Optimization, Process Safety

The Naphtha Clacking Center (NCC) downstream consists of various unit processes. A novel optimization model was developed for the Feasibility Study (Marketability, Techno Economic Analysis) configuring the optimal downstream units in terms of maximizing operating profit.

Marketability study considering Demand & Supply Analysis, Annual Average Gross Rate (AAGR), Product Price, Budget Limitation, Plant Location & Existing Raw Materials, Environmental Issues, etc. was performed as the first step, and Objective Function (i.e., maxΦ = Profit, IRR introduced as economic index), subject to constraints were defined at the Techno Economic Analysis stage where the binary variables represent C2/C3/C4/PyGas Derivatives as opportunity to investments and the integer variables correspond to the capacity of the derivative unit selected. The model can be formulated as a mixed integer linear programming (MILP) after proper linearization. When Light Naphtha, Wide-Range Naphtha (High Severity), and Wide-Range Naphtha (Mild Severity) are supplied as ethylene feeds, a total of 9 cases considering EO/EG production and C3 by OCU were configured. Based on the model, optimum configuration and optimal capacity could be proposed. (IRR up to 29.3%)

This study, which proposed the optimization result to the client at the Feasibility Study stage, was developed as an EPC project and is now in the commissioning stage. In addition to this study, CO2 emissions from Feedstock to the final product can be considered as one of the constraints of the optimization problem, and as a result, it can be proposed as an eco-friendly optimal configuration.