摘要
医疗垃圾焚烧排放烟气中含有汞和二恶英污染物,这两者均具有高毒性和较强的环境危害性。通常使用活性炭喷射法同时去除汞和二恶英,但该方法耗材高、成本大、存在着二次污染。为了解决上述问题,采用脉冲电晕低温等离子体技术处理汞和三氯苯(二恶英的模拟物),通过等离子体放电实现汞的氧化和三氯苯的降解,研究了电压、频率、脉宽、上升沿(即上升时间)对脉冲电晕等离子体同时去除汞和三氯苯的影响。结果表明:电压、频率对等离子体去除Hg^0和TCB有重要影响,在电压为17 kV时,最高可实现约65%的Hg^0氧化去除率,约70%的TCB去除率;脉宽、上升沿变化对二者的去除无明显影响;检测产物的主要物质为产生酮类、苯衍生物。综合上述结果,脉冲电晕等离子去除Hg^0和TCB的去除机制包括能量竞争和自由基反应,在能量竞争中,TCB具有明显优势。研究结果可为低温等离子体技术同时去除汞和二恶英的工业化应用提供参考。
There are mercury and dioxins pollutants in the flue gas from medical waste incineration, they are highly toxic and harmful to the environment and usually removed by the activated carbon injection method. This method is not conducive to long-term sustainable development due to its large consumable material, high cost and secondary pollution. In order to solve above problems, pulsed corona low temperature plasma was used to treat mercury and trichlorobenzene(the simulant of dioxins) in this study, the removal of these two pollutants will be achieved by plasma discharge. The effects of voltage, frequency, pulse width and rising time on the simultaneous removal of mercury and trichlorobenzene by pulse corona plasma were studied. The results showed that the voltage and frequency had significant influence on the removal of Hg^0 and TCB, at the voltage of 17 kV, the highest removal rates of Hg^0 and TCB reached about 65% and 70%, respectively. While the change of pulse width and rising edge had no obvious effect on the removal of Hg^0 and TCB. The main components in the products were ketones and benzene derivatives. Through the analysis, the removal mechanism of Hg^0 and TCB by pulsed corona plasma was determined as energy competition and free radical reaction. TCB had an obvious advantage in energy competition. The study provides a reference for the industrialization of the simultaneous removal of mercury and dioxins by low temperature plasma.
作者
姜媛媛
王俊峰
陈扬
梁美生
JIANG Yuanyuan;WANG Junfeng;CHEN Yang;LIANG Meisheng(College of Environmental Science and Engineering,Taiyuan University of Technology,Jinzhong 030600,China;Beijing Advanced Sciences and Innovation Centre,Chinese Academy of Sciences,Beijing 101407,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2020年第7期1878-1885,共8页
Chinese Journal of Environmental Engineering
基金
北京市科技怀柔科学城专项(Z181100003818009)
国家重点研发计划(2016YFC0209204)。
