Abundant mineral resources exist in the deep sea. However, in current deep-sea mining practices in China and abroad, tailwater is generally discharged directly into the middle layer of the ocean, leading to large-scale midwater plumes; and the carbon emissions of mother ships are extremely high. These have become core environmental bottlenecks restricting commercial deep-sea mining. To address these challenges, the study proposes a novel model for commercial deep-sea mining that leverages the green and low-carbon utilization of tailwater and exhaust gas. This model innovatively integrates source control with resource recovery, establishing a systematic pathway of "midwater plume control-resource transformation-synergistic enhancement." Based on the physicochemical properties of tailing mineral sludge, a safe treatment system encompassing "efficient flocculation-pressure filtration and dewatering-leaching desalination-heavy metal stabilization" is developed to prevent the formation of midwater plumes at the source, achieving solid-liquid separation, desalination, and harmless treatment of the sludge. Shipboard carbon capture and deep-sea sequestration technologies are integrated, capitalizing on the high-pressure and low-temperature conditions of the deep sea to realize mineralized sequestration of carbon dioxide in the form of hydrates. Carbon trading mechanisms are further incorporated to improve economic feasibility. The results indicate that, after safe treatment, the moisture content, salinity, and heavy metal concentrations in the tailing mineral sludge are significantly reduced, enabling its use in agricultural soils of islands and reefs, eco-friendly construction materials for island-reef systems, and daily chemical products, thereby creating considerable economic values. In parallel, the deep integration of exhaust gas carbon sequestration with mining operations minimizes redundant equipment and energy allocation, enhancing the overall operational efficiency of the system. Moreover, it offers a scalable technical solution for the low-carbon transition of marine engineering systems. The study also outlines future technological directions for the green and low-carbon utilization of tailwater and exhaust gas in commercial deep-sea mining. These include a safe treatment system for tailing mineral sludge aimed for large-scale commercial mining, coordinated development of deep-sea mining and agricultural cultivation on islands and reefs, green building material preparation technologies adapted to island and reef environments, integrated technologies for exhaust gas treatment and carbon sequestration, as well as technologies for producing high-quality daily chemical products from tailing mineral sludge. By establishing a circular system that integrates deep-sea mining, resource transformation, and industrial synergy, this study provides a systematic solution to overcome the environmental constraints in the commercial development of deep-sea resources, contributing an efficient technological paradigm to the global blue economy.