The potential of pulsed underwater streamer discharges as a disinfection technique
The potential of pulsed underwater streamer discharges as a disinfection technique
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DOI：
10.1109/tps.2008.2001231
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发表时间：
2008-08-01
影响因子：
1.5
通讯作者：
Bluhm, Hansjoachim
中科院分区：
文献类型：
--
作者：
Gupta, Suryakant B.;Bluhm, Hansjoachim
在本文中，我们调查的有效性，脉冲水下流光放电水消毒和其可扩展性大吞吐量。在本文中，我们已经建立了一个同轴流光反应器包含一个中心圆柱形阳极覆盖薄的多孔层的铁铝榴石。该反应器由振幅高达100 kV和脉冲持续时间在200和400 ns之间的电脉冲以高达20 Hz的重复率供电。不同的化学探针已被用作主要的诊断，以确定生产率和氧化剂在散装水中的积累。结果表明，拖缆的数量和长度与施加的电压幅值成线性关系，而脉冲持续时间只影响拖缆的长度。所有氧化剂的生产率与拖缆的数量长度乘积成线性比例。OH-自由基浓度高达100 mM出现在流光水边界。然而，由于拖缆的有限体积和OH自由基的有限范围，关于去污的最重要的氧化剂是H2 O2，其在水中积累，并且通过与来自拖缆的强UV辐射和冲击波相互作用，在主体水中产生OH自由基。将来自不同材料的装满水的比色皿放置在反应器中，我们发现冲击波对散装水中氧化剂产生的贡献似乎比紫外线辐射的贡献更重要。氧化剂的生产可以通过使合适的气体通过反应器的活性区来增强。最有效的是使用氧气。约20 J/cm（3）的电能需要减少恶臭假单胞菌的浓度由6个数量级。然而，尖端到180 J/cm（3）的比能量输入是必要的，以减少污水前的城市污水处理厂的细菌负荷只有两个数量级。这已经通过废水的高电导率来解释，对于相同的电参数，废水的高电导率大大减少了拖缆的长度。因此，它似乎不太可能单独的水下流光放电可以成为其他先进的氧化过程，如臭氧化，紫外线照射，或照射兆电子伏电子束的竞争力。然而，似乎可以想象，水下流光放电与臭氧化或其他过程相结合，可以导致一个更有效和经济的净化技术。
In this paper, we investigate the effectiveness of pulsed underwater streamer discharges for water disinfection and its scalability to large throughputs. For this paper, we have built a coaxial streamer reactor containing a central cylindrical anode covered by a thin porous layer of almandine. The reactor was supplied by electric pulses with amplitudes of up to 100 kV and pulse durations between 200 and 400 ns at a repetition rate of up to 20 Hz. Different chemical probes have been used as the main diagnostic to determine the production rates and the accumulation of oxidants in the bulk water. It has been found that the number and the length of streamers scaled linearly with the applied voltage amplitude, whereas the pulse duration only affected the streamer length. All oxidant production rates scaled linearly with the number-length product of streamers. OH-radical concentrations of up to 100 mM appear at the streamer-water-boundary. However, because of the limited volume of streamers and the limited range of OH radicals, the most important oxidant with respect to decontamination is H2O2 which accumulates in the water and, by interacting with the intense UV radiation and the shock waves from the streamers, produces OH radicals in the bulk water. Placing water-filled cuvettes from different materials in the reactor, we found that the contribution of shock waves to the production of oxidants in the bulk water seems more important than the contribution of UV radiation. The production of oxidants can be enhanced by percolating suitable gases through the active zone of the reactor. Most effective is the use of oxygen. About 20 J/cm(3) of electrical energy was required to reduce the concentration of Pseudomonas putida bacteria by six orders of magnitude. However, tip to 180 J/cm(3) of specific energy input was necessary to reduce the bacterial freight in waste water front a municipal sewage plant by just two orders of magnitude. This has been explained by the high conductivity of waste water which drastically reduces the length of streamers for the same electrical parameters. Therefore, it seems unlikely that underwater streamer discharges alone can become competitive with other advanced oxidation processes like ozonation, UV irradiation, or irradiation with megaelectronvolt electron beams. However, it seems conceivable that a combination of underwater streamer discharges with ozonation or other processes can lead to a more effective and economic decontamination technique.