China Longyuan Power Group Corporation Limited's carbon asset subsidiary has made significant progress with its self-developed project, "Research on Accurate Flue Gas Velocity Measurement Technology for Coal-fired Power Plant CO2 Emission Online Monitoring." The project recently passed a scientific and technological achievement appraisal organized by the Chinese Society for Electrical Engineering.
The technology has reached an internationally advanced level overall, with its "dynamic adjustment method for velocity field coefficients based on unit load changes in carbon emission online monitoring" leading globally. This innovation provides an effective technical solution to enhance the accuracy of carbon emission monitoring in coal-fired power plants.
Previously, the carbon monitoring field faced challenges such as difficulty in selecting uniform flue gas flow fields, low measurement precision for flue gas velocity, and irregular data comparison deviations. To address these issues, the project team introduced multi-dimensional innovations: - **Optimized measurement conditions**: By selecting optimal velocity measurement points, the team proposed a multi-channel ultrasonic flowmeter layout and channel weighting system setup method. Additionally, they developed an optical penetration and concentric sleeve positioning construction process to ensure alignment between upstream and downstream holes of the ultrasonic flowmeter, significantly improving cross-sectional velocity measurement accuracy. - **Improved calibration methods**: A 3D Pitot tube flowmeter comparison calibration method was introduced, incorporating wall correction and measurement point weighting coefficient optimization, effectively enhancing manual calibration precision. - **Dynamic velocity field coefficient adjustment**: A model was established to dynamically adjust velocity field coefficients based on unit load changes, enabling automatic coefficient adjustments during routine monitoring to further improve carbon emission flow measurement accuracy.
Currently, this technology has been successfully applied and verified at Unit #2 of National Energy Boxing Power Generation Co., Ltd. The relative deviation between the monitoring method and the calculated emissions remains stable within 3%, outperforming the average deviation level of domestic carbon monitoring. The minimal and stable deviation lays a foundation for the broader adoption of the monitoring method and its future application in the national carbon market, providing a practical implementation pathway for the promotion of carbon emission online monitoring technology.