A novel particle size distribution correction method based on image processing and deep learning for coal quality analysis using NIRS-XRF

Rui Gao; Jiaxin Yin; Ruonan Liu; Yang Liu; Jiaxuan Li; Lei Dong; Weiguang Ma; Lei Zhang; Peihua Zhang; Zhihui Tian; Yang Zhao; Wangbao Yin; Suotang Jia

doi:10.1016/j.talanta.2024.127427

A novel particle size distribution correction method based on image processing and deep learning for coal quality analysis using NIRS-XRF

Talanta. 2024 Dec 18:285:127427. doi: 10.1016/j.talanta.2024.127427. Online ahead of print.

Authors

Rui Gao¹, Jiaxin Yin¹, Ruonan Liu¹, Yang Liu¹, Jiaxuan Li¹, Lei Dong¹, Weiguang Ma¹, Lei Zhang², Peihua Zhang¹, Zhihui Tian³, Yang Zhao⁴, Wangbao Yin⁵, Suotang Jia¹

Affiliations

¹ State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan, 030006, China; Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China.
² State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan, 030006, China; Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China. Electronic address: k1226@sxu.edu.cn.
³ School of Physics and Electronic Information Engineering, Hubei Engineering University, Xiaogan, 432000, China.
⁴ School of Semiconductor and Physics, North University of China, Taiyuan, 030051, China.
⁵ State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan, 030006, China; Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, 030006, China. Electronic address: ywb65@sxu.edu.cn.

PMID: 39709828
DOI: 10.1016/j.talanta.2024.127427

Abstract

The combined application of near-infrared spectroscopy (NIRS) and X-ray fluorescence spectroscopy (XRF) has achieved remarkable results in coal quality analysis by leveraging NIRS's sensitivity to organic compounds and XRF's reliability for inorganic composition. However, variations in particle size distribution negatively affect the diffuse reflectance of NIRS and the fluorescence signal intensities of XRF, leading to decreased accuracy and repeatability in predictions. To address this issue, this study innovatively proposes a particle size correction method that integrates image processing and deep learning. The method first captures micro-images of the coal sample surface using a microscope camera and employs the Segment Anything Model (SAM) for binarization to represent particle size distribution. Subsequently, a Spatial Transformer Network (STN) is applied for geometric correction, followed by feature extraction using a Convolutional Neural Network (CNN) to establish a correlation model between particle size distribution and ash measurement errors. In experiments involving 56 coal samples, including 48 at 0.2 mm for the standard ash prediction model and 8 within a 0∼1 mm range for correction, the results showed significant improvements: standard deviation (SD), mean absolute error (MAE), and root mean square error of prediction (RMSEP) decreased from 0.321%, 0.317%, and 0.335% to 0.229%, 0.225%, and 0.257%, respectively. Using the accuracy of the 0.2 mm particle size validation set as a reference, compared to before correction, the errors in these metrics were reduced by 64.06%, 50%, and 60.80%, respectively. This study demonstrates that integrating deep learning and image analysis significantly enhances the repeatability and accuracy of NIRS-XRF measurements, effectively mitigating sub-millimeter particle size effects on spectral detection results and improving model adaptability. This method, through automated particle size distribution analysis and real-time result correction, holds promise for providing essential technical support for the development of online quality detection technologies for conveyor belt materials.

Keywords: CNN; NIRS; Particle size distribution; SAM; STN; XRF.