Techno-economic assessment of surfactant Huff-n-Puff EOR in shale plays via multi-objective optimization

Abstract

Surfactant Huff-n-Puff (HnP) has proven effective for enhanced oil recovery (EOR) in unconventional petroleum reservoirs. Due to the high cost of surfactant injectants, a comprehensive techno-economic analysis is crucial for optimizing development strategies. This study focuses on the Jimusar J305 shale oil reservoir, employing a Pareto-optimal multi-objective optimization (MOO) model to identify the best injection-production strategies for surfactant HnP. Using crude oil recovery and economic performance as objectives, the model combines numerical simulations with the multi-objective particle swarm optimization (MOPSO) algorithm. A decision-making protocol based on Pareto solutions is proposed to balance objectives, alongside an EOR mechanism analysis. Results show the net present value (NPV) improved from −2.98 million to +3.48 million USD without reducing oil recovery, indicating that different surfactant HnP strategies can achieve similar recovery outcomes but vary significantly in profitability. Optimal project design involves adjusting surfactant volume to reverse rock wettability and balancing injection rates and concentrations to enhance production while controlling costs.