The shipping industry, as a large carbon emitter, has attracted the attention of the international community. The International Maritime Organization (IMO) is the maker of carbon emission policies for the shipping industry and has successively issued a series of carbon emission reduction policies. The carbon emission policies of IMO in the last ten years have been reviewed. Based on the 2023 IMO Strategy on Reduction of GHG Emissions from Ships, the main influencing factors of key parameters corresponding to the mandatory measures in the current policies are studied, and typical sample ships are selected to calculate the key parameters, and to analyze the state-of-the-art and main problems of the carbon emissions from ocean-going vessels. The technological paths to address the mandatory parameters in the current shipping carbon emission reduction policies are explored based on the emissions of the shipping industry and the status of various technological paths, according to the Guidelines on Life Cycle GHG Intensity of Marine Fuels. It provides suggestions and references for the path selection and future technological development of the current shipbuilding industry to meet the IMO carbon emission policies.

The shipping industry, as a major emitter of greenhouse gases, has increasingly highlighted the urgency of carbon reduction. A series of mandatory policies and regulations on carbon emissions in the international shipping industry have gradually entered into the mandatory implementation stage in order to reduce carbon emissions in the shipping industry. The shipping industry is therefore facing enormous pressure on carbon reduction. The current study reviews and summarizes the shipping carbon emission policies and regulations issued by the International Maritime Organization (IMO), and compares the feasibility and applicability of various carbon reduction technologies in the shipping industry from both policy and technical aspects. The carbon capture technology is a direct and effective technology for the current shipping industry to address the carbon emission regulations. Based on the state-of-art of the carbon capture technology for ship exhaust gas, the challenges faced by the ocean-going ships in using carbon capture technology are analyzed from the technical requirements, operating costs and energy consumption, combined with the operation characteristics and exhaust emission characteristics of the ocean-going ships. The suggestions and measures are provided for appropriate marine carbon capture technology. The development direction of the carbon capture technology for the exhaust emissions of the ocean-going vessels is prospected based on the historical data. This study can provide references for the formulation of the carbon emission policies for China's shipping industry and the development and application of the ship carbon reduction technologies.