Modified local sands for the mitigation of harmful algal blooms
Anderson, Donald M.
MetadataShow full item record
KeywordHarmful algal bloom; Seawater; Modified sands; Chitosan; Polyaluminum chloride (PAC); Synergistic effect
A new method was developed for marine harmful algal bloom (HAB) mitigation using local beach sand or silica sand modified with chitosan and polyaluminum chloride (PAC). Untreated sand was ineffective in flocculating algal cells, but 80% removal efficiency was achieved for Amphidinium carterae Hulburt and a Chlorella sp. in 3 min (t80 = 3 min) using 120 mg L-1 sand modified with 10 mg L-1 PAC and 10 mg L-1 chitosan. After several hours 92% – 96% removal was achieved. The t80 for removing A. carterae using the modifiers only (PAC and chitosan combined) was 60 min and for Chlorella sp. 120 min, times which are much slower than with the corresponding modified sand. Sands were critical for speeding up the kinetic processes of flocculation and sedimentation of algal flocs. PAC was helpful in forming small flocs and chitosan is essential to bridge the small flocs into large dense flocs. Chitosan was also important in inhibiting the escape of cells from the flocs. Chitosan and PAC used together as modifiers make it possible to use local beach sands for HAB mitigation in seawater. Economical and environmental concerns could be reduced through the use of sands and biodegradable chitosan, but the potential impacts of PAC need further study.
Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Harmful Algae (2011): 381-387, doi:10.1016/j.hal.2011.01.003.
Showing items related by title, author, creator and subject.
Harmful algal blooms and eutrophication : examining linkages from selected coastal regions of the United States Anderson, Donald M.; Burkholder, JoAnn M.; Cochlan, William P.; Glibert, Patricia M.; Gobler, Christopher J.; Heil, Cynthia A.; Kudela, Raphael M.; Parsons, Michael L.; Rensel, J. E. Jack; Townsend, David W.; Trainer, Vera L.; Vargo, Gabriel A. (2008-07-28)Coastal waters of the United States (U.S.) are subject to many of the major harmful algal bloom (HAB) poisoning syndromes and impacts. These include paralytic shellfish poisoning (PSP), neurotoxic shellfish poisoning ...
The aggregation of clay minerals and marine microalgal cells : physicochemical theory and implications for controlling harmful algal blooms Sengco, Mario R. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2001-09)In recent years, the use of clay minerals has emerged as one of the most promising strategies for directly controlling harmful algal blooms (HABs). Its principle is based on the mutual aggregation of algal cells and ...
Anderson, Donald M.; Hoagland, Porter; Kaoru, Yoshi; White, Alan W. (Woods Hole Oceanographic Institution, 2000-09)Blooms of toxic or harmful microalgae, commonly called "red tides," represent a significant and expanding threat to human health and fisheries resources throughout the United States and the world. Ecological, aesthetic, ...