Refereed journal article or data article (A1)

Efficient harvesting of Chaetoceros calcitrans for biodiesel production

List of AuthorsSirin S, Clavero E, Salvado J


Publication year2015

JournalEnvironmental Technology


Journal acronymENVIRON TECHNOL

Volume number36

Issue number15

Start page1902

End page1912

Number of pages11



Harvesting is one of the key challenges to determine the feasibility of producing biodiesel from algae. This paper presents experimental results for a cost-effective system to harvest Chaetoceros calcitrans, using natural sedimentation, flocculation, and inducing pH. No efficient sedimentation of microalgal cells was observed only by gravity. By alkalinity-induced flocculation, at a pH value of 9.51, 86% recovery of the cells was achieved with a sedimentation rate of 125 cm/h and a concentration factor (CF) of 4 (volume/volume (v/v)) in 10 min. The maximum photochemical quantum yield of photosystem II (F-v/F-m) of concentrated cells was almost the same as fresh culture (0.621). Commercial flocculants, aluminium sulphate and poly-aluminium chloride (PAC), were also successful in harvesting the studied algal cells. Optimum concentration of aluminium sulphate (AS) could be concluded as 10 ppm with 87.6% recovery and 7.10 CF (v/v) in 30 min for cost-efficient harvesting, whereas for PAC it was 20 ppm with 74% recovery and 6.6 CF (v/v). F-v/F-m yields of concentrated cells with AS and PAC showed a 1% reduction compared to fresh culture. Mg+2 was the triggering ion for alkalinity-induced flocculation in the conditions studied. The rheology behaviour of the concentrated cells was Newtonian with values between 2.2 x 10(-3) and 2.3 x 10(-3) Pa s at 30 degrees C.

Last updated on 2021-24-06 at 10:49