State Grid Hubei Electric Power Research Institute
Hubei Fangyuan Dongli Electric Power Science & ResearchLimited Company
School of Energy Science and Engineering,Harbin Institute of Technology
State Grid Hubei Electric Power Co.,Ltd.

电力行业碳排放占全国总碳排放的40%以上,加快健全火电厂碳排放的精确计量和不确定度评定方法对电力行业碳排放精细化监管有重要作用。考虑到安装在电厂现场的浓度、流量等计量仪表长期运行后,其测量性能和精度发生变化,采用仪表出厂时的精度计算不确定度无法真实反映测量结果的可信度。提出了一种适用于生产实际,基于计量仪表定期检定结果的不确定度评定方法,并对湖北省某电厂660MW机组的碳排放在线监测结果进行不确定度评定,分析不确定度贡献,并提出优化建议。结果表明:该机组直测法碳计量结果的扩展相对不确定度为8.282%(包含因子k=2,置信水平95%)。除压强外,其余项均为B类不确定度占主导。是否考虑灵敏系数及B类不确定度评定方法的选择都会对结果产生显著影响。影响碳排放不确定度的主要来源为CO2浓度和烟气流量测量,采用更高精度的气体成分和流量测量仪器对测量仪表进行定期维护、校准以及优化烟道内测点布置等均有助于减小不确定度。

The carbon emission of the power industry accounts for more than 40% of the total carbon emission in China. Accelerating theimprovement of the accurate measurement and uncertainty assessment method of carbon emission of thermal power plants plays an important role in the fine supervision of carbon emission of the power industry. Considering that the measuring performance and accuracy ofthe concentration, flow and other measuring instruments installed on the power plant site may change after long-term operation, using thefactory accuracy of the meters to calculate the uncertainty cannot truly reflect the confidence level of the measurement. In this paper, animproved practical method for uncertainty assessment based on the periodic calibration results of the instruments was proposed. The methodwas used to evaluate the uncertainty of the online monitoring results of carbon emissions for a 660 MW power plant in Hubei Province,the contribution of uncertainty was analyzed, and optimization suggestions were proposed. The results show that the extended relative uncertainty of the carbon measurement results obtained by the direct measurement method is 8.282% (including factor k= 2, confidence level95%). With the exception of pressure, all other terms are dominated by class B uncertainty. Whether to consider the sensitivity coefficientand the choice of the evaluation method of Class B uncertainty will have a significant impact on the results. The main sources of carbonemission uncertainty are carbon dioxide concentration and flue gas flow measurement. The use of higher precision gas composition andflow measurement instruments, regular maintenance and calibration of measuring instruments, and optimization of measuring point layoutin the flue can help reduce the uncertainty.

国网湖北省电力有限公司成本专项资助项目(B11532232993)

黄辉,刘俊,崔洪滨,等.改进型火电机组烟气直测法碳计量不确定度评定方法[J].洁净煤技术,2024,30(8):42-49.

HUANG Hui,LIU Jun,CUI Hongbin,et al.Improved method for uncertainty evaluation of carbon measurement using fluegas direct measurement in thermal power unit[J].Clean Coal Technology,2024,30(8):42-49.