Effect of CO2 Gasification on Coal Burnout during Pressurized Oxy-Fuel Combustion by Experiment and Machine Learning Method

  • LEI Ming ,
  • YE Bin ,
  • TIAN Xi ,
  • HONG Dikun ,
  • ZHANG Qian ,
  • ZHANG Lei
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  • 1. Hebei Key Laboratory of Low Carbon and High Efficiency Power Generation Technology, North China Electric Power University, Baoding 071003, China
    2. School of Energy and Power Engineering, North China Electric Power University, Baoding 071003, China

网络出版日期: 2025-09-01

基金资助

This work is supported by National Key R&D Program of China (2024YFB4100081 and 2023YFB4104301). 

版权

Science Press, Institute of Engineering Thermophysics, CAS and Springer-Verlag GmbH Germany, part of Springer Nature 2025

Effect of CO2 Gasification on Coal Burnout during Pressurized Oxy-Fuel Combustion by Experiment and Machine Learning Method

  • LEI Ming ,
  • YE Bin ,
  • TIAN Xi ,
  • HONG Dikun ,
  • ZHANG Qian ,
  • ZHANG Lei
Expand
  • 1. Hebei Key Laboratory of Low Carbon and High Efficiency Power Generation Technology, North China Electric Power University, Baoding 071003, China
    2. School of Energy and Power Engineering, North China Electric Power University, Baoding 071003, China

Online published: 2025-09-01

Supported by

This work is supported by National Key R&D Program of China (2024YFB4100081 and 2023YFB4104301). 

Copyright

Science Press, Institute of Engineering Thermophysics, CAS and Springer-Verlag GmbH Germany, part of Springer Nature 2025

摘要

本研究通过实验与机器学习相结合的方法,分析了加压富氧燃烧条件下煤的燃尽特性。实验结果表明,煤的转化率随氧气浓度,温度及压力的升高显著提升。在低氧浓度条件下,CO2气化反应加速煤的消耗,导致CO2/N2气氛中的煤燃尽度低于O2/CO2气氛,且在高温高压下差异更为显著;随着氧气浓度增加,CO2气化作用减弱,同时受CO2物理性质影响,O2/N2条件下的煤燃尽度反超O2/CO2条件。此外,高压环境下CO2气化对低反应活性煤种转化的促进作用更为明显。基于实验数据,研究采用四种独立机器学习算法及一种集成算法构建煤粉燃尽度预测模型:首先通过皮尔逊相关系数分析特征参数(氧气浓度,加热温度,燃烧长度及反应气氛)与输出变量(煤燃尽度)的关联性;随后将输入数据分别训练四种基础模型,将其预测结果作为元模型的输入特征;优选梯度提升回归(GBR)作为Stacking集成学习的元模型,构建高精度煤燃尽度预测模型。最后,引入SHAP分析评估实验样本中煤燃烧预测结果的可解释性,显著提升了模型预测结果的物理意义阐释能力。

本文引用格式

LEI Ming , YE Bin , TIAN Xi , HONG Dikun , ZHANG Qian , ZHANG Lei . Effect of CO2 Gasification on Coal Burnout during Pressurized Oxy-Fuel Combustion by Experiment and Machine Learning Method[J]. 热科学学报, 2025 , 34(5) : 1721 -1735 . DOI: 10.1007/s11630-025-2170-x

Abstract

In the present study, the coal burnout during pressurized oxy-fuel combustion is analyzed by combining experiment and machine learning. According to the experimental results, it is shown that the coal conversion increases significantly with the increase of oxygen concentration, temperature and pressure. At relatively low oxygen concentration, CO2 gasification expedites the coal consumption, so the coal burnout in O2/N2 environment is lower compared to that in O2/CO2 environment, especially at elevated temperature and pressure. As the oxygen concentration increases, the influence of CO2 gasification weakens and on account of the CO2 physical properties, the coal burnout in O2/N2 condition is higher than that in O2/CO2 condition. Furthermore, the impact of gasification on the conversion of coal with low reactivity is obvious at high pressure. On the basis of the experimental data, four independent machine learning algorithms and one integrated machine learning algorithm are employed to propose a prediction model of pulverized coal burnout. The Pearson correlation coefficient between the characteristic parameters (oxygen concentration, heating temperature, combustion length, and reaction atmosphere) and the output variable (coal burnout) is calculated. And then the input data are independently trained by combining four different base models to generate a prediction of the target variable (coal burnout) which is used as the input characteristics of the meta-model. Moreover, the Gradient Boosting Regression (GBR) model is selected as the meta-model of Stacking ensemble learning to construct the accurate prediction model of coal burnout. Finally, the application of SHAP analysis is employed to assess the interpretability of the forecasted outcomes for coal combustion in the experimental samples, thereby significantly enhancing the explanatory capacity of the predicted results.

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