On-site algae harvesting system using tailored bubble flotation

Abstract

This study investigated the efficacy of an algae harvesting system based on tailored bubble flotation in lakes prone to lake eutrophication. To improve algae removal, a bubble generator for adjusting the size and amount of bubble charge was applied to the customized algae removal system. A coagulant, polyaluminum hydroxy chloro sulfate, was optimized at 10 mg/L to maximize its efficacy in sludge recovery. Field tests demonstrated substantial reductions in total nitrogen (TN) and total phosphorus (TP) in sediments, with efficiencies exceeding 80% and 85%, respectively. The final TN and TP concentrations were 1.97 and 0.06 mg/L, respectively, showing overall improvement in the region where the algae harvesting system operated. In addition, suspended solids, Chl-a, and chemical oxygen demand concentrations decreased with algae removal, leading to improved water quality. Therefore, the tailored bubble flotation system presents a viable solution for efficient algae management and overall water quality improvement in lakes and reservoirs.