School of Environment, Tsinghua University, Beijing, 100084, China.
School of Environment, Tsinghua University, Beijing, 100084, China.
Environ Pollut. 2020 May;260:113944. doi: 10.1016/j.envpol.2020.113944. Epub 2020 Jan 8.
Polycyclic aromatic hydrocarbons (PAHs) in soil are not only detrimental to environment but also to human health. Double dielectric barrier discharge (DDBD) plasma reactor used for the remediation of pyrene contaminated soil was studied. The performance of DDBD reactor was optimized with influential parameters including applied voltage, type of carrier gas, air feeding rate as well as pyrene initial concentration. The analysis of variance (ANOVA) results showed that input energy had a great effect on pyrene remediation efficiency followed by pyrene initial concentration, while, the effect of air feeding rate was insignificant. More specifically, the remediation efficiency of pyrene under air, nitrogen and argon as carrier gas were approximately 79.7, 40.7 and 38.2% respectively. Pyrene remediation efficiency is favored at high level of applied voltages and low level of pyrene initial concentration (10 mgkg) and air feeding rate (0.85 L/min). Moreover, computation of the energy efficiency of the DDBD system disclosed that an optimal applied voltage (35.8 kV) and higher initial pyrene concentration (200 mgkg) favored the high energy efficiency. A regression model predicting pyrene remediation under DDBD plasma condition was developed using the data from a face-centered central composite design (FCCD) experiment. Finally, the residual toxicity analysis depicted that the respiratory activity increased more than 21 times (from 0.04 to 0.849 mg O g) with a pyrene remediation efficiency of 81.1%. The study demonstrated the DDBD plasma technology is a promising method not only for high efficiency of pyrene remediation, but also recovering biological function without changing the physical-chemical properties of soil.
土壤中的多环芳烃（PAHs）不仅对环境有害，而且对人类健康也有害。研究了用于修复芘污染土壤的双介电阻挡放电（DDBD）等离子体反应器。通过包括施加电压、载气类型、空气进料速率以及芘初始浓度在内的影响参数优化了 DDBD 反应器的性能。方差分析（ANOVA）结果表明，输入能量对芘修复效率的影响最大，其次是芘初始浓度，而空气进料速率的影响则不显著。具体而言，空气、氮气和氩气作为载气时，芘的去除效率分别约为 79.7%、40.7%和 38.2%。在高施加电压水平和低芘初始浓度（10mgkg）和低空气进料速率（0.85L/min）下，芘的修复效率较高。此外，DDBD 系统的能量效率计算表明，最佳施加电压（35.8kV）和较高的初始芘浓度（200mgkg）有利于高能效。使用中心复合面设计（FCCD）实验的数据开发了预测 DDBD 等离子体条件下芘去除的回归模型。最后，残余毒性分析表明，芘去除效率为 81.1%时，呼吸活性增加了 21 倍以上（从 0.04 增加到 0.849mgO g）。该研究表明，DDBD 等离子体技术不仅是一种高效去除芘的方法，而且在不改变土壤物理化学性质的情况下恢复生物功能。
