This study aims to advance carbon emission reduction in China's shipping industry by evaluating the effectiveness of three widely used absorbents—Monoethanolamine (MEA), N-Methyldiethanolamine (MDEA), and Diglycolamine (DGA)—in carbon capture processes. Using Aspen Plus software, a carbon capture process model was constructed to investigate the effects of effects of absorbent flow rate and absorbent concentration on carbon capture rate, and the effects of desorption tower top pressure on carbon desorption rate and reboiler heat load. A comparative analysis of the absorption performance, desorption performance, and regeneration energy consumption of the three absorbents was carried out to identify the one with the optimal overall performance. The results indicate that all three absorbents are significantly influenced by variations in flow rate and concentration. MEA exhibited superior absorption performance relative to MDEA and DGA. Under identical simulation conditions, increasing the desorber top pressure resulted in a reduction in reboiler heat duty and a rise in reboiler outlet temperature. In terms of overall performance in absorption, desorption, and regeneration energy consumption, MEA outperformed both MDEA and DGA, suggesting its greater suitability for application in marine carbon capture systems.