The Challenge: Blue-green Algae Cause Operational Problems
Nuisant odours caused by periodic occurrence of excessive quantities of filamentous, and blue-green algae were posing operational problems at the facultative lagoon in Itapetininga, state of São Paulo.
The Solution: Control Algae with the LG Sonic e-line
Installation of a LG Sonic e-line device in a 20,000-m2 and 1.5-meter deep facultative oxidation lagoon in June 2012. The unit was connected to a local power source. Ultrasonic treatment uses high frequency sound waves to control algal blooms in lakes, reservoirs and other applications.
The Results: Up to 80% Reduction of Cyanobacteria
Water samples were taken weekly to assess the evolution of the algal population. The laboratory of Sabesp monitored the phytoplankton in the water in terms of chlorophyll-a and cyanobacteria concentration (micrograms per liter). Results are evident just after 2 weeks treatment. After 2 months, the results showed a significant reduction of pigment concentration in the effluent that could be discharged safely into the nearby surface water.