【摘要】 对大气压介质阻挡放电脱除甲醛进行了化学动力学模拟,建立了时空平均化的模型,并对相关的结果进行了实验验证.分析了各主要物种的浓度随放电时间的变化,在模拟空气气氛下,HCHO主要由O^·和OH^·自由基脱除,其中,OH^·自由基的作用更为突出.强调了氮分子的第一电子激发态N₂（A³∑_u⁺）的作用,它与O₂、H₂O分子的碰撞增加了O^·和OH^·自由基的浓度,在氮气气氛中,N₂（A³∑_u⁺）态是使HCHO脱除的主要物种.讨论了HCHO初始浓度、气体流量对HCHO脱除比能耗和产物中CO₂/CO摩尔比值的影响,HCHO初始浓度较高时,甲醛脱除的比能耗较低,在输入能量密度<60 J·L^-1,HCHO初始浓度较低时,产物中n_CO2/n_CO值较高.更多还原

【Abstract】 A time and space averaged chemical kinetics model in the removal of formaldehyde via a dielectric barrier discharge at atmospheric pressure and ambient temperature was reported.An analysis with regard to the discharge time evolution of the different main species was also included,and the results of the analysis showed that O^·and OH^·radicals,especially OH^·radicals,were the key species for the removal of HCHO.The role played by the first electronically excited metastable state N₂（A³∑_u⁺）was clarified that,in air,the chemical attacks of O₂ and H₂O by N₂（A³∑_u⁺） produced much more O^·and OH^·radicals.In nitrogen,N₂（A³∑_u⁺）made a great contribution in the removal of HCHO. Specific energy cost and the molar ratio of n_CO2/n_CO for HCHO removal at different HCHO initial concentrations and gas flow rates were also discussed.Specific energy cost at high HCHO initial concentration was lower than that at low HCHO initial concentration.If input discharge energy density<60 J·L^-1,n_CO2/n_CO at low HCHO initial concentration was higher than that at high HCHO initial concentration.更多还原