Preliminary Study on Control of Water Treatment Foam by Pulsed High Voltage Discharge

A novel method for controlling the foam of water treatment process using pulsed high voltage discharge has been developed. Bubbles formed by sodium lauryl sulfate solution are used to simulate foam formed in water treatment. The bubbles are destroyed during explosion of discharge when passing the gap between the two horizontally fixed stainless steel mesh electrodes above the water surface. The air in bubbles is released and the growth speed of the foam then can be decreased. When the air flow rates are 0.005 m³ldrs^-1 0.075 m³ldrs^-1 and 0.1 m³ldrs^-1 the most foam growth rates of 333 mgldrL^-1, 500 mgldrL^-1, 1000 mgldrL^-1 sodium lauryl sulfate solution and can be reduced by pulsed discharge to 10%-30% of the original rate without discharging. The best mitigation rate is 43.1% of 333 mgldrL^-1 sodium lauryl sulfate solution formed foam at the discharge voltage of 40 kV. The explosion of bubbles is the result of discharge streamers penetrating on the surface bubbles and the air released from the exploded surface bubbles.