O2/CO2条件下半焦-生物质的混燃特性及动力学分析OA北大核心CSTPCD

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.