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CLC number: TK6

On-line Access: 2021-02-05

Received: 2020-01-28

Revision Accepted: 2020-06-11

Crosschecked: 2021-01-10

Cited: 0

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Citations:  Bibtex RefMan EndNote GB/T7714


Zhong-yang Luo


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Journal of Zhejiang University SCIENCE A 2021 Vol.22 No.2 P.116-129


Behavior of alkali minerals in oxyfuel co-combustion of biomass and coal at elevated pressure

Author(s):  Oris Chansa, Zhong-yang Luo, Wen-nan Zhang, Chun-jiang Yu

Affiliation(s):  The State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China; more

Corresponding email(s):   zyluo@zju.edu.cn

Key Words:  Oxyfuel co-combustion, Equilibrium calculations, Chemical kinetic reactions, Mineral’, s identifications, Thermogravimetric combustion

Oris Chansa, Zhong-yang Luo, Wen-nan Zhang, Chun-jiang Yu. Behavior of alkali minerals in oxyfuel co-combustion of biomass and coal at elevated pressure[J]. Journal of Zhejiang University Science A, 2021, 22(2): 116-129.

@article{title="Behavior of alkali minerals in oxyfuel co-combustion of biomass and coal at elevated pressure",
author="Oris Chansa, Zhong-yang Luo, Wen-nan Zhang, Chun-jiang Yu",
journal="Journal of Zhejiang University Science A",
publisher="Zhejiang University Press & Springer",

%0 Journal Article
%T Behavior of alkali minerals in oxyfuel co-combustion of biomass and coal at elevated pressure
%A Oris Chansa
%A Zhong-yang Luo
%A Wen-nan Zhang
%A Chun-jiang Yu
%J Journal of Zhejiang University SCIENCE A
%V 22
%N 2
%P 116-129
%@ 1673-565X
%D 2021
%I Zhejiang University Press & Springer
%DOI 10.1631/jzus.A2000039

T1 - Behavior of alkali minerals in oxyfuel co-combustion of biomass and coal at elevated pressure
A1 - Oris Chansa
A1 - Zhong-yang Luo
A1 - Wen-nan Zhang
A1 - Chun-jiang Yu
J0 - Journal of Zhejiang University Science A
VL - 22
IS - 2
SP - 116
EP - 129
%@ 1673-565X
Y1 - 2021
PB - Zhejiang University Press & Springer
ER -
DOI - 10.1631/jzus.A2000039

Combustion of biomass or coal is known to yield aerosols and condensed alkali minerals that affect boiler heat transfer performance. In this work, alkali behavior in the pressurized oxyfuel co-combustion of coal and biomass is predicted by thermodynamic and chemical kinetic calculations. Existence of solid minerals is evaluated by X-ray diffraction (XRD) analysis of ashes from pressure thermogravimetric combustion. Results indicate that a rise in pressure affects solid alkali minerals negligibly, but increases their contents in the liquid phase and decreases them in the gas phase, especially below 900 °C. Thus, less KCl will condense on the boiler heat transfer surfaces leading to reduced corrosion. Increasing the blend ratio of biomass to coal will raise the content of potassium-based minerals but reduce the sodium-based ones. The alkali-associated slagging in the boiler can be minimized by the synergistic effect of co-combustion of sulphur-rich coal and potassium-rich biomass, forming stable solid K2SO4 at typical fluidized bed combustion temperatures. Kinetics modelling based on reaction mechanisms shows that oxidation of SO2 to SO3 plays a major role in K2SO4 formation but that the contribution of this oxidation decreases with increase in pressure.


结论:1. 压力升高对固体碱矿的影响可忽略不计.2. 提高生物质与煤的混合比,将提高钾基矿物质的含量,但会减少钠基矿物的含量.3. 锅炉中与碱相关的残渣可以通过富硫煤和富钾生物质的协同燃烧作用,在典型的流化床燃烧温度下形成稳定的固体K2SO4.3. 基于反应机制的动力学建模表明,在K2SO4的形成过程中,从SO2到SO3的氧化起着主要作用;但这种氧化的贡献会随着压力的增加而降低.


Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article


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