采用新型磁场和气流协同驱动旋转滑动弧等离子体,选取萘作为垃圾气化焦油模拟组分,在氮气气氛下开展了焦油裂解初步实验研究.重点考察了进样浓度、进气流量和预热温度对萘裂解效果及气体产物的影响;此外,采用气相色谱质谱联用仪(GC/MS)对液体副产物进行了表征.结果表明,当进气流量恒定时,随着进样浓度的提高,萘的降解率先升后降,在萘浓度为6mg/L时降解率达到最大值88.3%;随着进气流量从2L/min增加到12L/min,萘的降解率持续下降,由92.1%降至82.5%;提高预热温度可促进萘的降解.实验产生的主要气体产物为H2和C2H2,其选择性与萘的降解率变化趋势基本一致,最高分别为44.0%和13.7%;液体副产物主要有苯乙炔、茚、苊烯等,其 GC/MS峰面积比萘低2~3个数量级;在此基础上,对滑动弧反应区域中萘的降解路径及机理进行了初步探讨与分析.%In this study,a novel rotating gliding arc(RGA)plasma co-driven by a magnetic field and a tangential gas flow was used for tar decomposition. Naphthalene in nitrogen flow was proposed as a tar surrogate. The effects of injection concentration,gas flow rate and preheating temperature on naphthalene degradation efficiency and gas production were investigated. In addition,liquid byproducts were characterized by gas chromatography-mass spectrometry(GC/MS). With the rise of the injection concentration,the degradation efficiency of naphthalene increased first,reaching a maximum value of 88.3% at 6mg/L,and then decreased. With the rise of gas flow rate from 2L/min to 12L/min,the degradation efficiency of naphthalene decreased continuously from 92.1% to 82.5%. Increasing the preheating temperature could promote the degradation of naphthalene. The results showed that the main gas products were H2and C2H2,with maximum selectivity of 44.0% and 13.7% respectively. The variation trend of the selectivity of H2and C2H2were consistent with that of naphthalene degradation efficiency. The major liquid byproducts were acetylene,indene and acenaphthylene,whose GC/MS peak areas were 2—3 orders of magnitude lower than that of naphthalene. On this basis,the reaction pathways and mechanisms of naphthalene decomposition in the plasma zone were preliminary proposed and discussed.
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