Stochastic analysis in gasesolid two-phase flow in the dense-phase pneumatic conveying of pulverized coal

doi:10.1016/j.cjche.2025.04.002

Chinese Journal of Chemical Engineering ›› 2025, Vol. 83 ›› Issue (7): 26-37.DOI: 10.1016/j.cjche.2025.04.002

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Stochastic analysis in gasesolid two-phase flow in the dense-phase pneumatic conveying of pulverized coal

Yong Jin^1,2, Weizhong Gu^2,3

1 Shanghai Huayi Energy Chemical Co., Ltd., Shanghai 200241, China;
2 Guangxi Huayi Energy Chemical Co., Ltd., Qinzhou, Guangxi 535008, China;
3 Shanghai Huayi Holding Group Co., Ltd., Shanghai 200040, China

Received:2024-12-31 Revised:2025-03-28 Accepted:2025-04-01 Online:2025-07-28 Published:2025-07-28
Contact: Yong Jin,E-mail:jinyong@shhuayi.com
Supported by:
This work is supported by Shanghai Sailing Program and Guangxi Science and Technology Major Program. Dr. Yong Jin received funding from Shanghai Sailing Program (22YF1417600) and Guangxi Science and Technology Major Program (AA23062019).

Stochastic analysis in gasesolid two-phase flow in the dense-phase pneumatic conveying of pulverized coal

Yong Jin^1,2, Weizhong Gu^2,3

1 Shanghai Huayi Energy Chemical Co., Ltd., Shanghai 200241, China;
2 Guangxi Huayi Energy Chemical Co., Ltd., Qinzhou, Guangxi 535008, China;
3 Shanghai Huayi Holding Group Co., Ltd., Shanghai 200040, China

通讯作者: Yong Jin,E-mail:jinyong@shhuayi.com
基金资助:
This work is supported by Shanghai Sailing Program and Guangxi Science and Technology Major Program. Dr. Yong Jin received funding from Shanghai Sailing Program (22YF1417600) and Guangxi Science and Technology Major Program (AA23062019).

Abstract

Abstract: The complex dense-phase pneumatic conveying of pulverized coal process was studied using an electrical capacitance tomography (ECT) signal that represented the motion characteristics of gasesolid twophase flow. The fluctuation characteristics of conveying process signals are inseparable from the flow pattern. The denoised ECT signal and noise signal were obtained by db2 wavelet analysis. It was found that all noise signals were white Gaussian noise. Based on the assumption of the equal probability distribution of pulverized coal concentration, this paper proved that the time series distribution of pulverized coal concentration in the pipeline should obey the normal distribution. Furthermore, through the analysis of the distribution characteristics of the power spectral density function of denoised ECT signals of four flow patterns, they were a-dimensional fractal Brownian motion (fBm) signals, and the parameter a was estimated by the detrended fluctuation analysis. Based on the fBm characteristics of denoised ECT signals and white Gaussian noise, this paper proposed a method for calculating the pulverized coal concentration in the dense-phase pneumatic conveying. In addition to the method of concentration estimation with the significance of engineering guidance, this research can help people to further understand essential characteristics of ECT signals in the dense-phase pneumatic conveying.

Key words: Fractal Brownian motion, Detrended fluctuation analysis, Electrical capacitance tomography, Dense-phase pneumatic conveying, Noise

摘要： The complex dense-phase pneumatic conveying of pulverized coal process was studied using an electrical capacitance tomography (ECT) signal that represented the motion characteristics of gasesolid twophase flow. The fluctuation characteristics of conveying process signals are inseparable from the flow pattern. The denoised ECT signal and noise signal were obtained by db2 wavelet analysis. It was found that all noise signals were white Gaussian noise. Based on the assumption of the equal probability distribution of pulverized coal concentration, this paper proved that the time series distribution of pulverized coal concentration in the pipeline should obey the normal distribution. Furthermore, through the analysis of the distribution characteristics of the power spectral density function of denoised ECT signals of four flow patterns, they were a-dimensional fractal Brownian motion (fBm) signals, and the parameter a was estimated by the detrended fluctuation analysis. Based on the fBm characteristics of denoised ECT signals and white Gaussian noise, this paper proposed a method for calculating the pulverized coal concentration in the dense-phase pneumatic conveying. In addition to the method of concentration estimation with the significance of engineering guidance, this research can help people to further understand essential characteristics of ECT signals in the dense-phase pneumatic conveying.

关键词: Fractal Brownian motion, Detrended fluctuation analysis, Electrical capacitance tomography, Dense-phase pneumatic conveying, Noise

Yong Jin, Weizhong Gu. Stochastic analysis in gasesolid two-phase flow in the dense-phase pneumatic conveying of pulverized coal[J]. Chinese Journal of Chemical Engineering, 2025, 83(7): 26-37.

Yong Jin, Weizhong Gu. Stochastic analysis in gasesolid two-phase flow in the dense-phase pneumatic conveying of pulverized coal[J]. 中国化学工程学报, 2025, 83(7): 26-37.

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Stochastic analysis in gasesolid two-phase flow in the dense-phase pneumatic conveying of pulverized coal

Stochastic analysis in gasesolid two-phase flow in the dense-phase pneumatic conveying of pulverized coal

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