Water purification

About

Technology This is a novel process to treat water using a submerged arc discharge, which is effective in removal of undesirable biologically active molecules. The submerged arc (SA) is a high current electrical discharge between two electrodes submerged in water. The arc produces plasma, which in turn generates ultra-violet radiation and very active oxidant species, such as OH radicals, which can destroy biologically active molecules. Advantages The advantage of using plasma to decompose biological molecules in water is that it is simple, effective, and requires little or no chemical additives. However, until now the energy efficiency of this technology has been poor, making it prohibitively expensive. Our technology uses non-ferrous metallic electrodes and has demonstrated nearly one hundred times better purification per watt than other plasma technologies, making it a viable alternative to other processes such as direct UV irradiation and photocatalysis. Potential Applications Biologically active molecules of diverse sorts such as dyes, pharmaceuticals and pesticides find their way into water sources or ground water and there is a need to remove them to make the water safe for consumption. In some of these,due to the aromatic rings present in the molecules, conventional biological treatment does not effectively eliminate them. Water intended for human consumption should be generally free of these contaminations, and must be treated to remove, or alternatively inactivate the contaminants so that they are harmless. Furthermore, there is a danger that water sources might be intentionally contaminated. There is a need for processes and equipment for decontamination of water on several different scales: large scale permanent public water systems, medium scale portable installations for military units, disaster relief organizations, or expeditions which must temporarily rely on untreated natural water systems, and very small treatment equipment for individuals. In addition, in some circumstances it is desirable to treat waste water, in order to prevent spread of disease or to minimize environmental impact. Stage of Development A prototype system has been designed and tested on laboratory scale quantities of water with excellent results.