Practical Design
of Hybrid Photobioreactor System for Economic Feasibility and Environmental Sustainability
Sun Bill
Res. J. Chem. Environ; Vol. 27(9); 17-27;
doi: https://doi.org/10.25303/2709rjce017027; (2023)
Abstract
Modern photobioreactors for microalgae-based biofuel production face various budgetary
challenges in comparison to its competitor design, the traditional open pond system.
Herein, a novel design of a double-chamber hybrid photobioreactor is proposed, featuring
low-cost components including a 3-W centrifugal pump and recyclable plastic modules
for its solar flank, as well as derivatives from tubular and membrane photobioreactors.
The hybrid photobioreactor exhibits reasonable hydrodynamic performance with a circulation
time of 120 seconds and a mixing time of 38 seconds. A side-by-side runthrough of
Chlorella vulgaris cultivation with the novel hybrid photobioreactor and a standard
open pond system was done to compare growth rates and system performance under equal
environmental conditions. Resulting measurements show that the hybrid photobioreactor
produced a 34.87% comparatively greater amount of C. vulgaris by the tenth day of
cultivation, demonstrating a significantly higher growth rate (P < 0.05).
In contrast, wet-sludge lipid extraction processes show that the C. vulgaris culture
grown in the open pond system held a substantially larger lipid accumulation than
that of the hybrid photobioreactor, although the difference was not statistically
significant (P > 0.05). The pilot-scale photobioreactor not only costed as little
as the open pond system but also incurred 88.6% less expenses compared to a similarly
designed bioreactor made of clear PVC material. Consequently, this project demonstrates
the candidacy of the proposed low-cost hybrid photobioreactor design for microalgal
biofuel production.
