大气压降膜DBD等离子体去除废水中四环素

Removal of tetracycline from wastewater by atmospheric pressure falling film dielectric barrier discharge plasma

水体中抗生素类药物污染主要来源于人体和动物的大量使用,为改善水环境,降低和去除水中抗生素类药物,设计了可进行较大体积水中四环素的有效去除大气压降膜介质阻挡放电(dielectric barrier discharge)装置,研究了等离子体对四环素模拟液的降解特性,并分析了其降解机理。结果表明,当初始浓度为100 mg·L^-1,等离子体处理四环素溶液10 min,去除率为90%,化学需氧量去除率为45%,能量效率达到3.16 g·(kWh)^-1。较高的能量效率源自放电产生大量的活性物种(高能电子、离子、自由基等)。采用紫外可见分光光度法和液相色谱-质谱等检测方法对水样进行了分析,当等离子体放电处理2 min后,四环素溶液中开始生成新的物质,随着放电时间的延长,新物质种类和产量也随之逐渐增加,直至水中四环素接近完全降解。研究结果为实现大面积、工业级的有机抗生素废水的处理,保护水生生态环境提供了参考。

Antibiotics pollution in water mainly comes from the extensive use of human and animals. In order to improve water environment, reduce and remove antibiotics in water, an atmospheric falling film dielectric barrier discharge(DBD) device with coaxial cylinder was set up to remove the tetracycline in the large volumetric water. The degradation characteristics of tetracycline by plasma were discussed and the corresponding degradation mechanism was analyzed. The results showed that when the concentration of tetracycline was 100 mg·L^-1, the removal rates of tetracycline and COD reached 90% and 45% after only 10 minutes treatment, respectively, and the energy efficiency reached 3.16 g·(kWh)^-1. This high energy efficiency resulted from a large number of active species of high-energy electrons, ions, free radicals, etc. generated in the discharge process. The treated water samples were characterized by in-situ UV-vis spectrophotometer, pH meter,conductivity meter and liquid chromatography-mass spectrometry, the new intermediate products appeared after 2 min treatment. With the extension of electro-discharge time, the types and amount of new products increased until tetracycline was nearly completely decomposed. The above results provide a scientific basis for the treatment of large-scale and industrial-grade organic antibiotic wastewater and water ecological environment protection.