煤矸石与气化飞灰的热重-质谱混燃机理
Study on the co-combustion mechanism of coal gangue and coal gasification fly ash based on thermogravimetric mass spectrometry
林建功 1张孝禹 2惠吉成 3朱书骏 2朱建国4
作者信息
- 1. 中国科学院工程热物理研究所煤炭高效低碳利用全国重点实验室,北京 100190;山西大同大学煤炭工程学院,山西 大同 037009
- 2. 中国科学院工程热物理研究所煤炭高效低碳利用全国重点实验室,北京 100190
- 3. 中国科学院工程热物理研究所煤炭高效低碳利用全国重点实验室,北京 100190;华北电力大学能源动力与机械工程学院,北京 102206
- 4. 中国科学院工程热物理研究所煤炭高效低碳利用全国重点实验室,北京 100190;中国科学院大学,北京 100049
- 折叠
摘要
为了明确煤矸石与气化飞灰的混燃机理,在获得乌海煤矸石和宿迁气化飞灰理化特性的基础上,采用热重-质谱分析方法对乌海煤矸石、宿迁气化飞灰及其混合物的燃烧特性以及气体释放特性进行研究.热重分析结果表明:与宿迁气化飞灰相比,乌海煤矸石具有更好的着火特性,乌海煤矸石可提高混合燃料的着火性能,宿迁气化飞灰则可提高混合燃料的高温燃烧特性.基于Coats-Redfern(C-R)法、Flynn-Wall-Ozawa(FWO)法和Kissinger-Akahira-Sunose(KAS)法进行燃烧动力学特性分析,结果表明:乌海煤矸石表观活化能为 48.25～152.22 kJ/mol,燃烧反应符合Jander模型;宿迁气化飞灰表观活化能为106.34～312.79 kJ/mol,反应符合n=1/4的反应级数模型;乌海煤矸石与宿迁气化飞灰掺混的质量比为 1∶3时的表观活化能为 102.24～301.58 kJ/mol,反应符合成核生长模型.通过混合燃料质量变化速率理论值与测试值之间的偏差来探究各组分间的相互作用,结果表明:乌海煤矸石与宿迁气化飞灰混燃过程存在明显耦合作用,整体相互促进,改善了燃烧反应特性,相互促进作用随宿迁气化飞灰质量占比增加逐渐增强.综合燃烧特性与气体释放特性,乌海煤矸石与宿迁气化飞灰较佳的掺混质量比为 1∶3.含氮气体释放特性研究表明:在挥发分和固定碳燃烧阶段NH3 均有释放,NO和NO2 气体释放最高强度的峰值对应的温度与热重曲线最大反应速率对应的温度基本一致.
Abstract
The combustion characteristics and gas release characteristics of the Wuhai coal gangue,the Suqian coal gasi-fication fly ash,and their mixtures were revealed by thermogravimetric mass spectrometry analysis.The co-combustion mechanism of the Wuhai coal gangue and the Suqian coal gasification fly ash was studied by combining the physicochem-ical properties of the two fuels.The thermogravimetric analysis results indicate that the Wuhai coal gangue has better igni-tion characteristics than Suqian coal gasification fly ash.The ignition characteristics of the mixtures are improved by the Wuhai coal gangue,while the high-temperature combustion characteristics are improved by the Suqian coal gasification fly ash.The combustion kinetics were analyzed based on the Coats-Redfern(C-R),Flynn-Wall-Ozawa(FWO),and Kis-singer-Akahira-Sunose(KAS)methods.The results show that the apparent activation energy of the Wuhai coal gangue is 48.25-152.22 kJ/mol,and the combustion reaction conforms to the Jander model.The apparent activation energy of the Suqian coal gasification fly ash is 106.34-312.79 kJ/mol,and the reaction conforms to the reaction level model with n=1/4.When the mass ratio of the Wuhai coal gangue to the Suqian coal gasification fly ash was 1∶3,the apparent activa-tion energy was 102.24-301.58 kJ/mol,which corresponds to the synthesis of a nuclear growth model.The interaction of these fuels was examined by comparing the deviation between the theoretical and experimental weight loss rate of mix-tures.The results show that there is a significant coupling effect between the Wuhai coal gangue and the Suqian coal gasi-fication fly ash,mutually enhancing their combustion characteristics.This promoting effect is gradually strengthened with the increasing mass proportion of the Suqian coal gasification fly ash.Based on the comprehensive co-combustion charac-teristics and gas release characteristics,the better mass ratio of the Wuhai coal gangue to the Suqian coal gasification fly ash is 1∶3.NH3 is released during the volatile fraction and fixed carbon combustion process.The temperature corres-ponding to the peak intensity of the NO and NO2 release is essentially consistent with the temperature corresponding to the maximum reaction rate on the thermogravimetric curve.
关键词
煤矸石/气化飞灰/混燃机理/动力学Key words
coal gangue/coal gasification fly ash/co-combustion mechanism/kinetic analysis引用本文复制引用
出版年
2024
NETL
NSTL
万方数据