What is Corona Discharge? (Oxidation and Disinfection)

Corona discharge is a phenomenon that occurs when an electric field is applied to a gas, causing the gas to ionize and produce a glowing discharge of plasma. It’s named after the halo of ionized air (corona) that surrounds an electrically charged object.

Here’s how corona discharge works:

Electric Field Application: When a high voltage is applied to a conductor, such as a wire or electrode, placed in a gas (such as air or oxygen), an electric field is established around the conductor.

Ionization of Gas: The electric field causes the gas molecules near the conductor to become ionized. This means that the gas molecules gain or lose electrons, creating positively charged ions and negatively charged electrons.

Glowing Discharge: If the electric field is strong enough, the ionized gas molecules accelerate and collide with other gas molecules, leading to further ionization. This cascade of ionization results in a visible glow or discharge of plasma around the conductor, known as corona discharge.

Corona discharge is characterized by its faint, glowing appearance and can occur in various forms, such as uniform glow discharge or brush discharge. It’s commonly observed in applications like high-voltage transmission lines, where it can lead to power loss and audible noise due to the ionization of air surrounding the conductors.

In ozone generation using corona discharge, dry air or oxygen is passed through an electric field generated between two electrodes. The electric field ionizes the oxygen molecules (O2), splitting them into individual oxygen atoms (O), which then combine with other oxygen molecules to form ozone (O3). This ozone is then dissolved into water to provide disinfection or oxidation in water treatment applications. Corona discharge ozone generators are widely used in various industries for water treatment, air purification, and other applications requiring ozone production.