2.2. Dewatering
The algal concentration after growth in the open raceway pond
requires water removal before the biomass can be further processed.
In the experimental system excess water was removed
using a membrane filtration system which increased the algal
concentration from the harvest density of 1.5 g L1 to 40 g L1. A
centrifuge was then used to increase the algal concentration to
220 g L1. This concentration is adequate for bio-oil recovery
through HTL, but further water must be removed for bio-oil recovery
through pyrolysis. In the small-scale experimental system this
was done through lyophilizing. Microalgae mass losses in the
dewatering sub-process for the experimental system was modeled
at 15%