Liquid treatment device and liquid treatment method

A liquid treatment device comprising:

• a first metal electrode having a part disposed in a reaction tank into which a water being treated is filled;
• a second metal electrode disposed in the reaction tank;
• an insulator having an opening portion disposed to form a space between an outer circumference of the first metal electrode and the insulator, wherein a bubble is generated from the space to the water being treated via the opening portion;
• a gas supply device that supplies the space with a gas for generating the bubble;
• and
• a power supply that applies a voltage between the first metal electrode and the second metal electrode.

A liquid treatment method comprising:

• applying a voltage between a first metal electrode and a second metal electrode, at least a part of the first metal electrode disposed in a reaction tank into which a water being treated is filled, and the second metal electrode disposed in the reaction tank;
• supplying a closed space with a gas, where the closed space is formed by an insulator surrounding the first metal electrode;
• and
• generating a bubble in the water being treated from an opening portion of the insulator.