Investigation on the Occurrences and Interactions of Corrosive Species during Pyrolysis of Zhundong Coal Using SSNMR and HT-XRD

Xiongchao Lin, Yuanping Yang, Xujun Chen, Caihong Wang, Hayashi Jun-Ichiro, Yonggang Wang

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

The utilization of a typical Chinese low-rank coal (Zhundong coal) usually gives rise to severe fouling and slagging in equipment due to its excessively high content of sodium-bearing corrosive substances. This study systematically clarifies the occurrences and transformation mechanism of corrosive materials during pyrolysis of Zhongdong coal by combining solid-state nuclear magnetic resonance (SSNMR), in situ high-temperature X-ray diffraction (HT-XRD), and Factsage simulation. For the first time, the experimental evidence in this study shows that the corrosive elements demonstrated distinct forms in coal and could be significantly varied by thermal treatment. Specifically, homogeneously distributed Na ions could mutually transform between inorganic and organic-bounded form under the influence of ionic force, resulting in its elutable feature. During pyrolysis, Na was successively transformed to be inorganic form and completely volatilized above 800 °C, thus diversifying Na-related fouling propensity in various pyrolysis stages. The Cl was unlikely to entirely exist as inorganic form; nevertheless it was strongly restrained by functional groups of coal matrix. The organic Cl-containing functional groups was gradually decomposed to volatile Cl at pyrolysis temperature higher than 500 °C, whereas the inorganic Cl was more stable and possibly exposed on the surface of char particle. In situ analysis further revealed that the formation of aerosol by the diffused corrosive elements was the key step leading to the deposition. More importantly, Factsage thermodynamic calculation demonstrates that the sequential release of Cl as well as S, and their interactions with Na are the prerequisite and essential factor governing the generation of low-temperature-eutectic and subsequently initial corrosion.

Original languageEnglish
Pages (from-to)5062-5071
Number of pages10
JournalEnergy and Fuels
Volume32
Issue number4
DOIs
Publication statusPublished - Apr 19 2018

Fingerprint

Caustics
Coal
Pyrolysis
Nuclear magnetic resonance
X ray diffraction
Fouling
Functional groups
Bearings (structural)
Temperature
Aerosols
Eutectics
Sodium
Heat treatment
Thermodynamics
Ions
Corrosion

All Science Journal Classification (ASJC) codes

  • Chemical Engineering(all)
  • Fuel Technology
  • Energy Engineering and Power Technology

Cite this

Investigation on the Occurrences and Interactions of Corrosive Species during Pyrolysis of Zhundong Coal Using SSNMR and HT-XRD. / Lin, Xiongchao; Yang, Yuanping; Chen, Xujun; Wang, Caihong; Jun-Ichiro, Hayashi; Wang, Yonggang.

In: Energy and Fuels, Vol. 32, No. 4, 19.04.2018, p. 5062-5071.

Research output: Contribution to journalArticle

Lin, Xiongchao ; Yang, Yuanping ; Chen, Xujun ; Wang, Caihong ; Jun-Ichiro, Hayashi ; Wang, Yonggang. / Investigation on the Occurrences and Interactions of Corrosive Species during Pyrolysis of Zhundong Coal Using SSNMR and HT-XRD. In: Energy and Fuels. 2018 ; Vol. 32, No. 4. pp. 5062-5071.
@article{be1a7c331f6e4e8388aa5f4a2f977730,
title = "Investigation on the Occurrences and Interactions of Corrosive Species during Pyrolysis of Zhundong Coal Using SSNMR and HT-XRD",
abstract = "The utilization of a typical Chinese low-rank coal (Zhundong coal) usually gives rise to severe fouling and slagging in equipment due to its excessively high content of sodium-bearing corrosive substances. This study systematically clarifies the occurrences and transformation mechanism of corrosive materials during pyrolysis of Zhongdong coal by combining solid-state nuclear magnetic resonance (SSNMR), in situ high-temperature X-ray diffraction (HT-XRD), and Factsage simulation. For the first time, the experimental evidence in this study shows that the corrosive elements demonstrated distinct forms in coal and could be significantly varied by thermal treatment. Specifically, homogeneously distributed Na ions could mutually transform between inorganic and organic-bounded form under the influence of ionic force, resulting in its elutable feature. During pyrolysis, Na was successively transformed to be inorganic form and completely volatilized above 800 °C, thus diversifying Na-related fouling propensity in various pyrolysis stages. The Cl was unlikely to entirely exist as inorganic form; nevertheless it was strongly restrained by functional groups of coal matrix. The organic Cl-containing functional groups was gradually decomposed to volatile Cl at pyrolysis temperature higher than 500 °C, whereas the inorganic Cl was more stable and possibly exposed on the surface of char particle. In situ analysis further revealed that the formation of aerosol by the diffused corrosive elements was the key step leading to the deposition. More importantly, Factsage thermodynamic calculation demonstrates that the sequential release of Cl as well as S, and their interactions with Na are the prerequisite and essential factor governing the generation of low-temperature-eutectic and subsequently initial corrosion.",
author = "Xiongchao Lin and Yuanping Yang and Xujun Chen and Caihong Wang and Hayashi Jun-Ichiro and Yonggang Wang",
year = "2018",
month = "4",
day = "19",
doi = "10.1021/acs.energyfuels.8b00661",
language = "English",
volume = "32",
pages = "5062--5071",
journal = "Energy & Fuels",
issn = "0887-0624",
publisher = "American Chemical Society",
number = "4",

}

TY - JOUR

T1 - Investigation on the Occurrences and Interactions of Corrosive Species during Pyrolysis of Zhundong Coal Using SSNMR and HT-XRD

AU - Lin, Xiongchao

AU - Yang, Yuanping

AU - Chen, Xujun

AU - Wang, Caihong

AU - Jun-Ichiro, Hayashi

AU - Wang, Yonggang

PY - 2018/4/19

Y1 - 2018/4/19

N2 - The utilization of a typical Chinese low-rank coal (Zhundong coal) usually gives rise to severe fouling and slagging in equipment due to its excessively high content of sodium-bearing corrosive substances. This study systematically clarifies the occurrences and transformation mechanism of corrosive materials during pyrolysis of Zhongdong coal by combining solid-state nuclear magnetic resonance (SSNMR), in situ high-temperature X-ray diffraction (HT-XRD), and Factsage simulation. For the first time, the experimental evidence in this study shows that the corrosive elements demonstrated distinct forms in coal and could be significantly varied by thermal treatment. Specifically, homogeneously distributed Na ions could mutually transform between inorganic and organic-bounded form under the influence of ionic force, resulting in its elutable feature. During pyrolysis, Na was successively transformed to be inorganic form and completely volatilized above 800 °C, thus diversifying Na-related fouling propensity in various pyrolysis stages. The Cl was unlikely to entirely exist as inorganic form; nevertheless it was strongly restrained by functional groups of coal matrix. The organic Cl-containing functional groups was gradually decomposed to volatile Cl at pyrolysis temperature higher than 500 °C, whereas the inorganic Cl was more stable and possibly exposed on the surface of char particle. In situ analysis further revealed that the formation of aerosol by the diffused corrosive elements was the key step leading to the deposition. More importantly, Factsage thermodynamic calculation demonstrates that the sequential release of Cl as well as S, and their interactions with Na are the prerequisite and essential factor governing the generation of low-temperature-eutectic and subsequently initial corrosion.

AB - The utilization of a typical Chinese low-rank coal (Zhundong coal) usually gives rise to severe fouling and slagging in equipment due to its excessively high content of sodium-bearing corrosive substances. This study systematically clarifies the occurrences and transformation mechanism of corrosive materials during pyrolysis of Zhongdong coal by combining solid-state nuclear magnetic resonance (SSNMR), in situ high-temperature X-ray diffraction (HT-XRD), and Factsage simulation. For the first time, the experimental evidence in this study shows that the corrosive elements demonstrated distinct forms in coal and could be significantly varied by thermal treatment. Specifically, homogeneously distributed Na ions could mutually transform between inorganic and organic-bounded form under the influence of ionic force, resulting in its elutable feature. During pyrolysis, Na was successively transformed to be inorganic form and completely volatilized above 800 °C, thus diversifying Na-related fouling propensity in various pyrolysis stages. The Cl was unlikely to entirely exist as inorganic form; nevertheless it was strongly restrained by functional groups of coal matrix. The organic Cl-containing functional groups was gradually decomposed to volatile Cl at pyrolysis temperature higher than 500 °C, whereas the inorganic Cl was more stable and possibly exposed on the surface of char particle. In situ analysis further revealed that the formation of aerosol by the diffused corrosive elements was the key step leading to the deposition. More importantly, Factsage thermodynamic calculation demonstrates that the sequential release of Cl as well as S, and their interactions with Na are the prerequisite and essential factor governing the generation of low-temperature-eutectic and subsequently initial corrosion.

UR - http://www.scopus.com/inward/record.url?scp=85045913932&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85045913932&partnerID=8YFLogxK

U2 - 10.1021/acs.energyfuels.8b00661

DO - 10.1021/acs.energyfuels.8b00661

M3 - Article

VL - 32

SP - 5062

EP - 5071

JO - Energy & Fuels

JF - Energy & Fuels

SN - 0887-0624

IS - 4

ER -