Biorefinery Processing of Waste to Supply Cost-Effective and Sustainable Inputs for Two-Stage Microalgal Cultivation

Overcoming obstacles to commercialization of algal-based processes for biofuels and co-products requires not just piecemeal incremental improvements, but rather a comprehensive fundamental re-consideration starting with the selected algae its associated cultivation, harvesting, biomass conversion, refinement. A novel two-stage process designed address challenges mass outdoor microalgal cultivation was previously demonstrated using an oleaginous, haloalkaline-tolerant, multi-trophic green Chlorella vulgaris. ALP2 from soda lake. This involved cultivating microalgae in fermenter heterotrophically or photobioreactor mixotrophically (first-stage) rapidly obtain high cell densities inoculate open-pond phototrophic culture (second-stage) featuring levels NaHCO3, pH, salinity. An improved that instead sustainably used as more cheap sustainable inputs organic carbon, nitrogen, phosphorous fractionation waste here small-scale biorefinery process. The first stage consisted two simultaneous batch flask cultures (1) mixotrophic productivity 7.25 × 107 cells mL−1 day−1 on BG-110 medium supplemented 1.587 g L−1 urea enzymatic hydrolysate pre-treated (torrefaction + grinding ozonolysis soaking ammonia) wheat-straw corresponded 10 glucose, (2) 2.25 purified de-toxified condensate grinding) wheat straw 0.350 potassium acetate. second featured 1H NMR-determined lipid 0.045 triacylglycerides (TAG) 16.8 NaHCO3 fed batch-added 22% (v/v) anaerobically digested food effluent at HCl-mediated pH 9.