Bioremediation of Wastewater using Chlorella Vulgaris Microalgae: Phosphorus and Organic Matter

Document Type: Original Research Paper

Authors

1 Chemical Engineering Department, EEI, University of Vigo, 36310 Vigo, Spain

2 Defense University Center, Escuela Naval Militar, Plaza de España 2, 36920 Marín, Spain

Abstract

Wastewater contains many organic and inorganic contaminants that can cause serious damage to the environment and health of people, Therefore, they have to be eliminated before being downloaded into sensitive areas. Different methods of wastewater purification have been used for contaminants removal. However, they present some technical and economic limitations. Thus, new methods of nutrients removal by microalgae based on phytoremediation techniques, become promising methods due to its viability. The objective of wastewater treatment is to improve and purify the water. For that, the removal of all or some of the nutrients present in water is carried out, resulting in a reusable or suitable water to be returned to its natural environment. This study investigates the capacity of Chlorella Vulgaris microalga as a potential candidate for removing the phosphorous and organic matter from wastewater. The strain of microalga was cultivated in synthetic wastewater at room temperature with artificial illumination and aeration. Algal growth parameters such as pH, chemical oxygen demand, phosphorus, cell number, optical density and dry weight were measured during experimental period. Under these conditions, microalgae were able to remove the phosphorus concentration by more than 99%. By other hand, the chemical oxygen demand was reduced at 71 %. After 9 days of cultivation, the biomass concentration increased from 0.05 to 0.57 g/L. The results of this study suggest that growing Chlorella Vulgaris microalgae in wastewater offers a new option of applying algae to manage the nutrient load. After then obtained biomass can be used for biofuel production.

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