Growing Chlorella vulgaris on mixed wastewaters for biodiesel feedstock production and nutrient removal

Abstract

BACKGROUND Large water footprint and nutrients demand are two of the major issues during microalgae cultivation. In this study, anaerobically digested swine manure was mixed with centrate at different minimal dilution multiples (2×, 3×, 4×, 6× and 8×), which was used as media to cultivate Chlorella vulgaris (UTEX 2714) for reducing the production cost of algae cultivation and balancing the nutrient profiles of culture media. RESULTS Chlorella vulgaris (UTEX 2714) grew well on the mixed wastewaters with a biomass productivity of 132.2 to 440.3 mg L−1 d−1. Nutrients in the mixed wastewaters were removed effectively by this alga, and the removal efficiencies of ammonium (NH4+‐N), total nitrogen (TN), chemical oxygen demand (COD) and total phosphorus (TP) ranged from 98.3, 46.9, 30.2 and 21.8 to 99.3, 71.4, 42.2 and 80.4%, respectively. Additionally, chemical compositions, such as pigments, carbohydrate, protein and lipids, in this alga varied with the change of dilution multiple due to the different nutrient profiles of culture media. Predicted properties of biodiesel from the oils of this alga satisfied the specifications of biodiesel, ASTM D6751‐08 and EN 14214 standards. CONCLUSION Biomass of C. vulgaris (UTEX 2714) can be used as a good‐quality feedstock for biodiesel production when grown on mixed wastewaters. This novel integration of using mixed wastewaters to cultivate microalgae would be an effective way to reduce the production cost of algal biomass. © 2018 Society of Chemical Industry

Glucose addition‐induced changes in the growth and chemical compositions of a freshwater microalga Chlorella kessleri

“…Microalgae desirability is related to their biochemical compositions, such as protein, carbohydrate, lipids and pigments, whose synthesis and accumulation would be affected by the cultivation conditions where they are cultivated . Based on the biomass of C. kessleri , changes of biochemical compositions with culture conditions were evaluated and depicted in Fig.…”

“…Microalgae desirability is related to their biochemical compositions, such as protein, carbohydrate, lipids and pigments, whose synthesis and accumulation would be affected by the cultivation conditions where they are cultivated. 44 Based on the biomass of C. kessleri, changes of biochemical compositions with culture conditions were evaluated and depicted in Fig. 5, which showed that contents of protein, carbohydrate, lipids and pigments in the algal cells were 50.6%, 17.2%, 24.7% and 2.47%, respectively, when this alga was cultivated in the photoautotrophic cultures.…”

Cultivation of Chlorella sorokiniana using wastewaters from different processing units of the silk industry for enhancing biomass production and nutrient removal

“…Similar results were reported by Zheng et al . and Deng et al ., who found that the mixture of different wastewaters had a better nutrient profile for algae growth than the individuals.…”

Nutrients removal and biomass production from anaerobic digested effluent by microalgae: A review

“…The fatty acids profiles were different with the change of dilution multiple of ADE. The predicted properties of biodiesel fit for the biodiesel standards of ASTM D6751-08 and EN 14214 [72] . Chung et al [68] cultivated Spirulina sp.…”

“…Additionally, some studies also investigated the chemical compositions in the microalgae from the ADE media, such as pigments, carbohydrate, protein and lipids, especially the fatty acids profiles which could be a potential way to determine some important properties of biodiesel [57,72] . Deng et al [72] investigated the potential biodiesel feedstock production and nutrient removal of Chlorella vulgaris (UTEX 2714) cultivation in the anaerobically digested swine manure. The fatty acids profiles were different with the change of dilution multiple of ADE.…”