摘要
微波催化燃烧技术将微波辐照与吸波型催化剂相结合,可用于对挥发性有机化合物(VOCs)进行催化燃烧处置。研制了Pt/CuMnCeO_(x)/堇青石和Pt/CuMnCeO_(x)/纳米陶瓷整体式蜂窝状催化剂,并开发了微波催化燃烧VOCs的装置,将其应用于印刷包装行业的VOCs治理。通过操作条件的优化,考察了微波催化燃烧技术对VOCs的实际处理效果。同时,对催化剂表面形貌、比表面积和晶体结构等进行了测试分析。结果表明:Mn_(3)O_(4)/Mn_(2)O_(3)、CeO_(2)/Ce_(2)O_(3)、CuMn_(2)O_(4)和PtO等尖晶石的存在降低了反应温度、提高了储氧释氧能力和催化剂活性;催化剂的介孔结构和较大的比表面积有利于VOCs在孔隙内部的扩散,并可延长VOCs在催化剂上的停留时间。在催化剂床层体积330 L、微波功率13.6 kW、进气质量浓度1520 mg·m^(-3)和进气量440 m^(3)·h^(-1)的条件下,床层温度可达到420℃,此时催化剂床层温度及VOCs去除率保持稳定。当进气质量浓度分别为约4500 mg·m^(-3)和2800 mg·m^(-3)时,VOCs的去除率分别为90%和96%。考察燃烧热量发现,大气量的VOCs在催化剂表面的停留时间短且带走热量多,从而导致VOCs去除率下降;高浓度VOCs在燃烧时会因释放出更多热量,从而提高床层温度和VOCs去除率。在确保催化剂表面活性位点充足的条件下,微波催化燃烧工艺适合处理中高浓度的印刷包装行业VOCs。同时,利用VOCs燃烧释放的热量来保持床层高温,还可达到节能降耗的目的。本研究可为印刷包装行业的VOCs治理提供参考。
Microwave catalytic combustion is a new catalytic combustion technology that combining microwave irradiation with microwave-absorbing catalyst closely.Based on the development of microwave catalytic combustion device and the exploitation of monolithic honeycomb catalysts of both Pt/CuMnCeO_(x)/cordierite and Pt/CuMnCeO_(x)/nano ceramic,this new technology was applied to treat volatile organic compounds(VOCs)exhausting from a printing and packaging factory on the spot.The real removal rate of VOCs by microwave catalytic combustion was investigated through an optimization of different operating conditions.Subsequently,surface morphology,specific surface area and crystal structure of the catalysts were characterized in this study.It indicated that the existence of Mn_(3)O_(4)/Mn_(2)O_(3),CeO_(2)/Ce_(2)O_(3),CuMn_(2)O_(4) and PtO spinels reduced reaction temperature and improved oxygen reserving-releasing ability and catalytic activity of the catalysts greatly.The mesoporous structure and abundant specific surface area of the catalysts are beneficial to the diffusion of pollutants in the inner pores and can prolong the retention time of targets on the surface of the catalysts simultaneously.The research work showed that bed temperature reached 420℃and VOCs removal rate kept at steady under the conditions(330 L of bed volume,13.6 kW of microwave power,1520 mg·m^(-3) of inlet concentration and 440 m^(3)·h^(-1) of airflow).The removal rates of VOCs exhaust were 90%and 96%when the inlet concentration was about 4500 mg·m^(-3) and 2800 mg·m^(-3),respectively.The retention time of VOCs on the surface of the catalyst was shortened and much more heat was taken away with the increase of airflow,which resulted in a decrease of VOCs removal rate.VOCs exhaust with high concentration released more heat while burning,which increased bed temperature apparently and improved VOCs removal rate obviously.The new technology was confirmed to be suitable for the treatment of VOCs with medium or high concentration on condition that sufficient active sites are provided onto the surface of the catalyst.Simultaneously,heat releasing from VOCs combustion can maintain high temperature of catalyst bed so that additional energy do not need to be provided,which save energy and reduce cost in the operation.This study carves out a new way for the treatment of VOCs from printing and packaging industry.
作者
张丹庆
卜龙利
陈瑾
张继宾
田野
刘嘉栋
ZHANG Danqing;BO Longli;CHEN Jin;ZHANG Jibin;TIAN Ye;LIU Jiadong(School of Environmental and Municipal Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China;Key Laboratory of Northwest Water Resources,Environment and Ecology,Ministry of Education,Xi'an 710055,China;Key Laboratory of Environmental Engineering of Shaanxi Province,Xi’an 710055,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2022年第2期524-534,共11页
Chinese Journal of Environmental Engineering
关键词
微波加热
印刷包装VOCs
催化燃烧
去除率
影响参数
microwave heating
VOCs exhausting from printing and packaging industry
removal rate
catalytic combustion
influencing parameters
