Microalgal Growth in Paper Industry Effluent: Coupling Biomass Production with Nutrients Removal

Paper and pulp industries produce effluents with high phosphorus concentrations, which need to be treated before their discharge in watercourses. The use of microalgae for this purpose has attracted the attention of researchers because: (i) microalgae can assimilate phosphorus (one of the main nutri...

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Bibliographic Details
Main Authors: Bruna Porto, Ana L. Gonçalves, Ana F. Esteves, Selene M. A. Guelli Ulson de Souza, Antônio A. Ulson de Souza, Vítor J. P. Vilar, José C. M. Pires
Format: Article
Language:English
Published: MDPI AG 2020-04-01
Series:Applied Sciences
Subjects:
Online Access:https://www.mdpi.com/2076-3417/10/9/3009
Description
Summary:Paper and pulp industries produce effluents with high phosphorus concentrations, which need to be treated before their discharge in watercourses. The use of microalgae for this purpose has attracted the attention of researchers because: (i) microalgae can assimilate phosphorus (one of the main nutrients for their growth); and (ii) growing on effluents can significantly reduce the costs and environmental impact of microalgal biomass production. This study evaluated the growth and ability of <i>Chlorella vulgaris</i> to remove the phosphorus from a secondary-treated effluent of a Portuguese paper company. Batch experiments were performed for 11 days using different dilutions of the effluent to evaluate its inhibitory effect on microalgae. Results showed that the non-diluted effluent inhibited microalgal growth, indicating that this bioremediation process is possible after a previous dilution of the effluent. Regarding phosphorus removal, promising results were achieved, especially in the experiments conducted with the most diluted effluent: removal efficiencies obtained in these conditions were (54 ± 1)%. Another interesting finding of this study was microalgal growth in flakes’ form (mainly due to the compounds present in the effluent and to the pH values achieved), which can be an important economic advantage for biomass recovery after the remediation step.
ISSN:2076-3417