Harvesting green algae from eutrophic reservoir by electroflocculation and post-use for biodiesel production

Enrique Valero; Xana Álvarez; Ángeles Cancela; Ángel Sánchez

doi:10.1016/j.biortech.2015.03.138

Harvesting green algae from eutrophic reservoir by electroflocculation and post-use for biodiesel production

Bioresour Technol. 2015:187:255-262. doi: 10.1016/j.biortech.2015.03.138. Epub 2015 Apr 1.

Authors

Enrique Valero¹, Xana Álvarez², Ángeles Cancela³, Ángel Sánchez⁴

Affiliations

¹ AF4 Research Group, Department of Natural Resources and Environment Engineering, Forestry Engineering College, University of Vigo, Campus A Xunqueira s/n, 36005 Pontevedra, Spain. Electronic address: evalero@vigo.es.
² AF4 Research Group, Department of Natural Resources and Environment Engineering, Forestry Engineering College, University of Vigo, Campus A Xunqueira s/n, 36005 Pontevedra, Spain. Electronic address: giaf4_5@uvigo.es.
³ Chemical Engineering Department, Industrial Engineering College, University of Vigo, Campus Lagoas-Marcosende s/n, 36310 Vigo, Pontevedra, Spain. Electronic address: chiqui@vigo.es.
⁴ Chemical Engineering Department, Industrial Engineering College, University of Vigo, Campus Lagoas-Marcosende s/n, 36310 Vigo, Pontevedra, Spain. Electronic address: asanchez@uvigo.es.

PMID: 25863202
DOI: 10.1016/j.biortech.2015.03.138

Abstract

Each year there are more frequent blooms of green algae and cyanobacteria, representing a serious environmental problem of eutrophication. Electroflocculation (EF) was studied to harvest the algae which are present in reservoirs, as well as different factors which may influence on the effectiveness of the process: the voltage applied to the culture medium, run times, electrodes separation and natural sedimentation. Finally, the viability of its use to obtain biodiesel was studied by direct transesterification. The EF process carried out at 10V for 1min, with an electrode separation of 5.5cm and a height of 4cm in culture vessel, obtained a recovery efficiency greater than 95%, and octadecenoic and palmitic acids were obtained as the fatty acid methyl esters (FAMEs). EF is an effective method to harvest green algae during the blooms, obtaining the greatest amount of biomass for subsequent use as a source of biodiesel.

Keywords: Biodiesel; Cyanobacterial blooms; Kirchneriella sp.; Microcystis sp.; Scenedesmus spp..

MeSH terms

Biofuels / microbiology*
Chlorophyta / growth & development*
Chlorophyta / radiation effects
Drinking Water / microbiology
Electrochemistry / methods*
Electromagnetic Fields
Eutrophication
Flocculation*
Water Pollutants / isolation & purification*
Water Purification / methods*
Water Supply

Substances

Biofuels
Drinking Water
Water Pollutants