Investigation on cofiring high-alkali coal with coal gangues: SO2, NO reduction and ash slagging inhibition

被引：0

作者：

Huang S. ^{[1
]}

Zhang L. ^{[1
,2
]}

Yan J. ^{[1
]}

Wang Z. ^{[3
]}

Lei Z. ^{[1
]}

Li Z. ^{[1
]}

Ren S. ^{[1
]}

Wang Z. ^{[3
]}

Shui H. ^{[1
]}

机构：

[1] School of Chemistry & Chemical Engineering, Anhui University of Technology, Anhui, Ma’anshan

[2] School of Computer Science and Technology, Anhui University of Technology, Anhui, Ma’anshan

[3] College of Chemistry and Chemical Engineering, Dezhou University, Shandong, Dezhou

来源：

Huagong Xuebao/CIESC Journal | 2022年 / 73卷 / 12期

关键词：

ash fusion temperatures; coal gangues; high-alkali coal; slagging and fouling; SO[!sub]2[!/sub] and NO reduction;

D O I：

10.11949/0438-1157.20221221

中图分类号：

学科分类号：

摘要：

Slagging and fouling are common problems in high-alkali coal-fired boilers. Meanwhile, a large amount of solid waste coal gangue from coal mining and coal washing needs to be reduced and utilized for economical and ecological considerations. Given this, cofiring high-alkali coal (HAC) with coal gangues (CG) was performed to verify the possibility of inhibiting ash-related problems of HAC meanwhile achieving resource utilization of CG. Besides, the evolution behaviors of pollution gases (SO2 and NO) were examined. The results show that cofiring reaction follows a three dimensional diffusion model, and at proper ratios the activation energy of cofiring can be lower than that of mono-combustion. NO can be efficiently reduced during cofiring with the enhanced catalytic components in the blended fuels, while the reduction of SO2 is largely determined by the blending ratio and ash compositions. Alkali metals are effectively retained in ashes thus lowering the fouling and slagging propensity, while alkaline metals participate the competitive reaction with silica and alumina components and that of SO2 fixation reactions. The ash fusion temperatures can be adjusted through cofiring with CG with various inherent minerals, thus providing the opportunity to alleviate the ash-related problems for burning HAC in commercial boilers. © 2022 Chemical Industry Press. All rights reserved.

引用

页码：5581 / 5591

页数：10

共 34 条

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