Hydrophyte July2020 Vol24 3

Page 17

www.sfapms.org

page 17

CONTROL ALGAE WITH NANOBUBBLES How nanobubbles work to treat lakes and ponds where traditional methods fail By Christian Ference, Application Engineer, Master of Science, Civil and Environmental Engineering, University of Pittsburgh Swanson School of Engineering Traditionally, aquatic management companies have relied on two methods for managing algae blooms in lakes, ponds, and water features: namely, chemicals (like algaecides and alum) and conventional aeration. Algaecides directly control algae by breaking down algae cells while alum removes phosphate (a known stimulant of algae blooms) from water by causing it to settle to the bottom of the warterbody. Aeration is used to dissolve and circulate oxygen in a waterbody in an effort to reduce nutrient levels that contribute to algae blooms. While chemicals and aeration can be effective in reducing the severity of algae blooms, there are environmental consequences and economic factors that need to be considered for both treatment methods.

A new chemical-free algae control method is being applied across the United States to accelerate the treatment of harmful algae using tiny bubbles of oxygen called nanobubbles. In this piece, we’ll explore the benefits of this new treatment method against traditional options. Chemicals (Algaecides and alum) Copper sulphate and hydrogen peroxide are algaecides commonly used to treat algae blooms. These chemicals break apart, or lyse, algae cells, disrupting the cell’s integrity and reducing the severity of an algae bloom. Alum (aluminum sulfate) is a chemical used for treating high levels of phosphorous that cause algae blooms by pulling the phosphorous out of the water and trapping it in the sediment.