Plasma-based methods and systems for treating waters with high electrical conductivity and/or low surface tension

An electrical discharge plasma reactor system for treating a liquid, the reactor system comprising:

• a reactor chamber configured to hold the liquid and a gas;
• a discharge electrode disposed within the reactor chamber, wherein the discharge electrode is disposed within the gas;
• an opposing electrode disposed within the gas within the reactor chamber;
• one or more gas diffusers disposed within the liquid, wherein the one or more gas diffusers is configured to induce the generation of a layer of foam on a surface of the liquid in a plasma-contact region;
• wherein the one or more gas diffusers are connected to the reactor chamber beneath the liquid, which is between the one or more gas diffusers and the gas;
• and
• a power supply connected to the discharge electrode and/or the opposing electrode, the power supply configured to induce the discharge electrode and the opposing electrode to generate plasma in a plasma-contact region;
• wherein the discharge electrode and the opposing electrode are separated by a distance such that the plasma generated forms a continuous spark that contacts a surface of the liquid as it spans the distance between the electrodes.

A method for treating a liquid, the method comprising the steps of:

• providing an electrical discharge plasma reactor including a reactor chamber configured to hold the liquid and a gas;
• positioning a discharge electrode in the reactor chamber above a surface of the liquid;
• positioning an opposing electrode in the reactor chamber above the surface of the liquid, wherein the opposing electrode is separated from the discharge electrode by an interelectrode gap;
• delivering voltage to at least the discharge electrode and inducing the discharge electrode and the opposing electrode to generate plasma in a plasma-contact region on the surface of the liquid to degrade at least one component dissolved within the liquid;
• and
• generating foam in the plasma-contact region on the surface of the liquid.