Image credit:
Upflow
May 12, 2026

Lab-work to test biomass post-processing options

A recent lab-scale trial has explored spray drying as a biomass drying and stabilisation method for Galdieria

Biomass post-processing is a critical step that involve supgrading a raw or pre-treated biomass into more stable or higher-value products. This might be through densification, drying, thermal, or chemical treatment.

In our trial, a total of 20 litre  of the Galdieria biomass culture was harvested from the 80L bioreactor. The biomass was first concentrated by centrifugation, then resuspended in buffer to a final volume of ~2L. This volume was selected to approximate the biomass concentration expected after filtration under the proposed pilot-plant design. The suspension was then processed into a dryer material using a laboratory‑scale spray dryer at the Chemical and Process Engineering facilities at the University of Canterbury.

The dried biomass was a matte emerald‑green colour, consistent with late‑stage cultures entering early glycogen accumulation. The spray‑dried product was a fine, strongly agglomerating powder withmoderate to low apparent bulk density. Spray drying proved to be effective for moisture removal and biomass stabilisation.

Spray drying apparatus at University of Canterbury, and dried biomass after processing (Photos: Cristian Martinez, Upflow)