A simultaneous optimization of the seawater bittern and waste seashell recovery process for CO2 and SOx utilization

This study proposes a novel integration of seawater bittern and waste seashell recovery processes for CO2 and SOx utilization. Furthermore, simultaneous optimization of waste seashells and Ca(OH)2 separated from seawater bittern as an SOx absorbent was conducted to derive the blending ratio using a genetic algorithm (GA). The GAbased optimization process consists of four steps: (1) data generation using process model and data preprocessing, (2) DNN-based surrogate model development to predict the gypsum purity, CaCO3 yield, and CO2 emissions, (3) mathematical model development for TAC calculation, (4) GA-based optimization to derive the cost-optimal blending ratio and TAC. As a result, the derived cost-optimal blending ratios were scallop shells (0.03 %), cockle shells (0.03 %), clam shells (13.66 %), oyster shells (40.31 %), mussel shells (28.80 %), and Ca (OH)2 (17.18 %), reducing the TAC by up to 10.88 % compared to conventional CO2 and SOx capture processes. At the optimal blending ratio, the recycling efficiency of each seashell in the Republic of Korea was achieved from a minimum of 2.72 % to a maximum of 99.15 % annually. Therefore, this work makes a significant contribution to the chemical engineering field, providing an environmentally friendly, economical process and an efficient simultaneous optimization framework applied to the proposed model.