Development of a harvesting technique for large-scale microalgal harvesting for biodiesel production

Abstract

Harvesting methods executed in lab and large-scale for efficient and sustainable harvesting of microalgae and supernatant reuse for recultivation.

Effective Harvesting of Nannochloropsis Microalgae Using Mushroom Chitosan: A Pilot-Scale Study

“…Mixing using a paddle-wheel system may provide a better flocculation performance as the mechanism less disruptive to the large flocs as they pass through. Koley et al (2017) have demonstrated the effectivity of chitosan with flocculation efficiencies of ∼90% to flocculate Scenedesmus obliquus and Chlorella vulgaris cultured in raceway ponds. However, the cultures had to be pumped into 1000-L tanks, which was easier to mix with a large motor-driven stirrer.…”

Current advances in microalgae harvesting and lipid extraction processes for improved biodiesel production: A review

“…The high efficiency can be explained as chitosan has dual characteristics of charge neutralization and bridging, where protonated amine and hydroxyl groups mark chitosan as a good adsorbent. These active sites increase the surface interaction of chitosan with microalgal cells and assist in bridging and sedimentation of the cells [37].…”

“…The mechanism behind is, wWhen the alum is added to the aqueous medium, aluminum hydroxide is formed, which is cationic in nature. The formation of superficial cationic charge interacts with negatively charged microalgal cells and hence neutralization of charge occurs as a result, cells forms flocs and settle [37]. FeCl3 is trivalent cation, which has been reported with 100 times higher flocculation efficiency than monovalent cations [56].…”

Application of machine learning for development of a drying protocol for microalga Chlorella minutissima in a single rotary drum dryer for biodiesel production

“…Before cultivation in raceway ponds, the selected microalga was scaled-up in the UZn medium (Koley, Mathimani, Bagchi, Sonkar, & Mallick, 2019), and was acclimatized to the outdoor condition as detailed in Sonkar, Deb, & Mallick (2020). The raceway ponds were operated at 30 cm of culture depth with a corresponding culture volume of 16000 L. Harvesting of the microalgal biomass was carried by pH-induced flocculation using NaOH at pH 12 for 12 h following Koley, Prasad, Bagchi, & Mallick (2017).…”