The construction of a full-chain greenhouse gas accounting system for CCUS projects is an important aspect of large-scale promotion of CCUS technology to achieve net emission reduction, and it is also an effective measure to cope with the compliant operation requirements such as the latest International Sustainability Disclosure Board (ISSB) standards. In view of this, this paper starts from the "time boundary-physical boundary-accounting boundary" analysis of CCUS operation, focuses on the core links such as "capture stage-transportation stage-utilization stage-storage stage", embeds Scope 1, Scope 2 and Scope 3 greenhouse gas accounting methods, tries to construct a theoretical system of full-chain accounting in the CCUS construction and operation cycle, and constructs a life-cycle greenhouse gas accounting index system for CCUS projects based on the data availability of CCUS operation in reality. Furthermore, in the actual accounting process, this paper also points out the key steps and effective measures of full-chain accounting in the operation of CCUS projects in China are based on the requirements of international ISSB standards and the data indicators of greenhouse gas accounting. The research in this paper lays a foundation for improving the full-chain accounting of greenhouse gases in China, especially for the verification of the net emission reduction contribution of CCUS projects.

The insufficient economic viability of CCUS project operations and the inadequate incentive policy system are significant bottlenecks hindering the development of coal-based CCUS projects. This study employs the ITEAM-CCUS model to evaluate the comprehensive economic characteristics of CCUS project operations and conducts an in-depth analysis using the Jinjie Power Plant 150 kt/a CCUS demonstration project as a case study. The research identifies differentiated strategies for the required intensity of single incentive policies and the comprehensive effects of policy combinations, as well as their impact on the economic feasibility of CCUS project operations. The findings reveal that: ① the ITEAM-CCUS model assessment indicates that coal-based CCUS projects possess substantial emission reduction potential and demonstrate favorable economies of scale at both regional and enterprise levels; ② the case analysis suggests that during the early demonstration phase of CCUS projects, deterministic incentive policies such as generation hour compensation and feed-in tariff subsidies should be implemented. In contrast, market-oriented policies like carbon trading and green power trading are more suitable for the operational promotion phase; ③ different policy combinations exhibit varying impacts on the levelized capture cost of CCUS projects, with a comprehensive policy system significantly supporting CCUS project operations. The study recommends enhancing economic policy support for CCUS project operations and adopting differentiated policies at various stages to improve the economic feasibility of coal-fired CCUS operations.