Algae removal characteristics of the ultrasonic radiation enhanced drinking water treatment process

Abstract

Algal blooms have become a critical environmental problem and affect the water quality of drinking water treatment plants. This study investigated the effects of different ultrasonic methods on Microcystis aeruginosa and enhanced drinking water treatment processes. Results showed that the removal rate of algae cells increased with the extension of time and the removal effect of static ultrasound was better than that of dynamic ultrasound. However, the release of algae organics and algae toxins was less in dynamic ultrasound radiation. Scanning electron microscope (SEM) and transmission electron microscope (TEM) analyses showed that ultrasonic radiation destroyed parts of the cell structure but not the integrity of the algae cells' membrane and wall. The coagulation experiment found that short-time ultrasonic radiation can promote the coagulation effect and improve the removal efficiency of algae cells and organics. The 740 kHz ultrasonic enhanced water purification process significantly improves the removal efficiency of algae cells in the sedimentation tank, reduces the treatment pressure of the filter, and releases less algae cell substances, reducing the risk of disinfection by-products generation. This study provides a reference for the application of ultrasound in water purification technology and is of great significance in ensuring water quality safety.