Flotation of algae for water reuse and biomass production: role of zeta potential and surfactant to separate algal particles.
The effect of chemical coagulation and biological auto-flocculation relative to zeta potential was examined to compare flotation and sedimentation separation processes for algae harvesting. Experiments revealed that microalgae separation is related to auto-flocculation of Anabaena spp. and requires chemical coagulation for the whole period of microalgae cultivation. In addition, microalgae separation characteristics which are associated with surfactants demonstrated optimal microalgae cultivation time and separation efficiency of dissolved CO2 flotation (DCF) as an alternative to dissolved air flotation (DAF). Microalgae were significantly separated in response to anionic surfactant rather than cationic surfactant as a function of bubble size and zeta potential. DAF and DCF both showed slightly efficient flotation; however, application of anionic surfactant was required when using DCF.
Department of Environmental and Chemical Engineering, Seonam University, 439 Chunhyang-ro, Namwon 590-711, Republic of Korea E-mail: kwak124@hanmail.net.
Dong-Heui
DH
Kwak
Industry Technology Research Institute of Seonam University, 439 Chunhyang-ro, Namwon 590-711, Republic of Korea.
Mi-Sug
MS
Kim
D017033:Anabaena; D018533:Biomass; D005427:Flocculation; D058086:Microalgae; D013501:Surface-Active Agents; D014867:Water
D013501:Surface-Active Agents; D014867:Water