Dense Medium Plasma Remediation of VOCs in Groundwater

地下水是地球上最重要的淡水资源之一。然而，地下水污染已成为美国日益严重的问题。在许多类型的污染物中，挥发性有机化学品（VOC）是一个主要问题，对那些使用地下水供应饮用水的人来说是一个潜在的人类健康威胁。泵送和处理技术是最广泛使用的地下水修复方法之一，当与其他修复方法（包括高级氧化技术）结合使用时，可以有效。重介质等离子体技术是一种高效的AOT技术，用于处理抽取的地下水中的VOCs。与通常用于在泵送和处理地下水修复应用中破坏饱和烃的其他现有AOT相比，该AOT技术需要更少的能量输入，产生上级修复性能，可以以连续模式操作以获得高通量，并且可以按比例放大用于工业用途。在大气压和环境温度下，水反应堆通过水引发、维持和分散放电。浸没式微放电产生的高能量产生多种活性物质，包括臭氧（O3）、过氧化氢（H2 O2）和自由基（例如H？（OH？其可与地下水中的VOC相互作用，并通过氧化、裂解和重组将其转化为CO2、H2O和其他危害较小的碳氢化合物。初步测试已经进行了消毒反应器净化和消毒水样，人为污染的四种挥发性有机化合物或感染了16个选定的细菌。从初步测试中获得的数据表明，在进行任何优化之前，该反应器能够将苯、甲苯、乙苯和二甲苯（全部）的VOC浓度降低到可检测范围（从ppm到ppb）以下，并且细菌污染水平降低高达99.9%。在这项拟议的努力中，将建立和修改原型反应堆，以满足地下水修复应用中通常发现的要求。将评估该技术对特定VOC（包括1，4-二氧六环、TCE、MTBE和高氯酸盐）的有效性。将优化处理参数，以实现最佳的补救效果。副产品将被识别和研究，以评估DMPs的环境影响，并在必要时建议二级处理方法。通过这项拟议的研究开发的最终产品是一种商业设备，可以单独使用（单个单元或阵列）或与其他现有技术结合使用，以破坏提取的地下水中的VOC和其他类似的化学污染物。由于美国75%的公共供水系统依赖地下水，水污染，特别是挥发性有机化学品（VOCs），已成为日益严重的威胁公众健康。拟议的工作为现有的地下水中VOCs处理技术提供了一种更高效和更有效的替代方案，有助于减轻环境原因造成的人类疾病和功能障碍的负担。

DESCRIPTION (provided by applicant): Groundwater is one of the most important freshwater resources on this planet. However, contaminated groundwater has become an ever-increasing problem in the United State. Among the many types of contaminants, Volatile Organic Chemicals (VOCs) are a major concern and a potential human health threat for those who use groundwater for the supply of drinking water. Pump-and-treat technology is one of the most widely used groundwater remediation approaches, and can be effective when combined with other remediation methods, including Advanced Oxidation Technologies (AOTs). The Dense Medium Plasma (DMP) technology is a highly efficient AOT for treatment of VOCs in extracted groundwater. Compared to other existing AOTs that are often used to destroy saturated hydrocarbons in pump-and-treat groundwater remediation applications, the DMP technology requires less energy input, produces superior remediation performance, can operate in continuous mode for high throughput, and can be scaled up for industrial use. The DMP reactor initiates, sustains, and disperses electrical discharges through water at atmospheric pressure and ambient temperature. High energies generated by the submerged micro- discharges produce a variety of reactive species including ozone (O3), hydrogen peroxide (H2O2), and free radicals (e.g. H? and OH?), which can interact with VOCs in groundwater and convert them into CO2, H2O, and other less harmful hydrocarbons through oxidation, fragmentation, and recombination. Preliminary tests have been performed on the DMP reactor to decontaminate and disinfect water samples that were artificially contaminated with four VOCs or infected with 16 selected bacteria. Data obtained from the preliminary tests demonstrated that the DMP reactor, prior to any optimization, was able to reduce VOC concentrations of benzene, toluene, ethyl benzene, and xylene (all) below the detectable range (from ppm to ppb) and bacteria contamination levels by up to 99.9% . In this proposed effort, a prototype DMP reactor will be built and modified to meet the requirements typically found in groundwater remediation applications. Effectiveness of the technology against particular VOCs, including 1, 4-dioxane, TCE, MTBE, and per chlorate, will be evaluated. Treatment parameters will be optimized to achieve the best remediation performance. Byproducts will be identified and studied to evaluate the DMPs environmental impact and secondary treatment approaches will be suggested if necessary. The final product to be developed through this proposed research study is a commercial device that can be used either alone (single unit or an array) or in combination with other existing technologies to destroy VOCs and other similar chemical contaminants in extracted groundwater. As 75% of public water systems in the United States rely on groundwater, water contamination, especially by Volatile Organic Chemicals (VOCs), has become an increasingly serious threat to the public health. The proposed work provides a more efficient and effective alternative to existing technologies for treatment of VOCs in groundwater, helping to reduce the burden of human illness and dysfunction from environmental causes.