School of Energy and Power Engineering, Xi’an Jiaotong University
School of Chemical Engineering and Technology, Xi’an Jiaotong University

半焦与生物质在O2/CO2条件下混燃是实现碳基燃料清洁高效利用和碳减排的重要途径,准确掌握其混燃特性及动力学特性尤为关键。通过热重分析和正交实验研究了半焦与三种生物质(稻壳、松木、核桃壳)在O2/N2和N2/CO2气氛下混燃的燃烧特性、交互作用及反应动力学。结果表明:O2/N2气氛下掺混生物质可改善半焦的着火和燃尽特性,O2/CO2气氛下掺混生物<PAGE-1>质可改善半焦的着火特性,但会延迟半焦的燃尽。半焦和生物质在主燃区存在明显的交互作用,该作用显著提高了混燃反应性和燃烧强度,降低了着火活化能。生物质掺混比增大,燃烧特性指数提高,混合燃料低温区的活化能E1和高温区的活化能E2均逐渐降低;掺混生物质为松木时,混燃特性最好,掺混生物质为稻壳时,混燃特性次之,掺混生物质为核桃壳时,混燃特性再次之。与O2/N2气氛相比,O2/CO2气氛下的综合燃烧特性指数降低,E1和E2都提高,提高O2/CO2气氛中的O2体积分数可小幅改善燃烧特性。燃烧气氛对燃烧特性和活化能的影响最显著,生物质掺混比的影响次之,掺混生物质的种类的影响最小,但若只考虑O2/CO2气氛的O2体积分数变化,燃烧气氛对混燃特性的影响很小。

Co-combustion of semi-coke and biomass with oxy-fuel combustion technology is a significant method for clean and high-efficiency utilization of carbon-based fuel and CO2 emis-sion reduction. It is particularly crucial to clarify the co-combustion characteristics and kinetics properties of semi-coke and biomass. Thermogravimetric analysis and orthogonal experiments were carried out to investigate the co-combustion characteristics, interactions and reaction kinet-ics of semi-coke (SC) and three types of biomass (rice husks, pine wood, walnut shells, denoted by dk, sm, htk respectively) in the atmospheres of O2/N2 and O2/CO2. The results show that in O2/N2 atmosphere, the additive of biomass can improve both the ignition and burnout character-istics of semi-coke. However, in O2/CO2 atmosphere, blending of biomass can enhance the igni-tion characteristics, but delay the burnout of semi-coke. There is a significant interaction be-tween semi-coke and biomass in the main combustion zone, which plays a crucial role in enhan-cing the co-combustion reactivity and reducing the activation energy of the blends. As the blend-ing ratio of biomass increases, the combustion characteristic index improves, and activation ener- gies in both low-temperature (E1) and high-temperature zones (E2) gradually decrease. The or-der of blends based on combustion characteristics from good to second is SC-sm, SC-dk, SC-htk. Compared to those in O2/N2 atmosphere, the comprehensive combustion characteristic index de-creases in O2/CO2 atmosphere with E1 and E2 increasing. A slight improvement in combustion characteristic index can be achieved by increasing O2 volume fraction in O2/CO2 atmosphere also leading to the reduction of activation energy. The combustion atmosphere plays the most signifi-cant role in determining the co-combustion characteristics, followed by the blending ratio of bio-mass, while the type of blended biomass has the least impact. However, if only considering the O2 volume fraction variation in the O2/CO2 atmosphere, the influence of the combustion atmos- phere appears to be relatively weak.

国家自然科学基金项目(52206171,52006170).

张锦萍,陈 磊,王长安,等.O2/CO2 条件下半焦-生物质的混燃特性及动力学分析[J].煤炭转化,2024,47(3):1-12

ZHANG Jinping,CHEN Lei,WANG Chang’an,et al.Co-combustion characteristics and kinetics analysis of semi-coke and biomass in O2/CO2 atmosphere[J].Coal Conversion,2024,47(3):1-12