The transition away from chemical flocculants: Commercially viable harvesting of Phaeodactylum tricornutum

Harvesting can contribute up to 15% of the total production cost for microalgal biomanufacturing. Using flocculants is potentially a cost-effective approach but there has been considerable debate on efficacy, cost, toxicity cell and environment, effect biomass further downstream. In this study, range biobased (chitosan from crab shells, Moringa oleifera seed extract, pectin bananas, tannic acid-based derivatives Acacia tree bark egg shell powder) were compared with traditional chemical (aluminium sulphate, iron chloride sodium hydroxide) harvesting diatom Phaeodactylum tricornutum. It was concluded that Tanac’s tannin based Tanfloc 8025 (SL range) most promising, requiring low concentration (10.4 kg ton?1 biomass), at ($27.04 biomass). The flocculant effective over wide pH (7.5–10.0) temperature (15–28 °C) (>85% efficiency) occurred in 10 mins, which resulted factor ? 5.69.