Remoción de nitratos y fosfatos por cepas nativas de Chlorella sp. (Chlorellaceae) y Chlamydomonas sp. (Chlamydomonadaceae) libres e inmovilizadas en aguas residuales municipales.

Removal of inorganic nutrients from wastewaters by microalgae is an efficient and productive method, which provides oxygenation to water bodies and useful biomass for several industries. The aim of this investigation was to determinate the nitrate (N-NO3-) and phosphate (PO43-) removal capacity by free and immobilized cultures of native strains of Chlorella sp. (Chlorelaceae) and Chlamydomonas sp. (Chlamydomonadaceae) in municipal wastewaters. Removal experiments were performed in sterile wastewater effluents from the same plant during 10 days. Microalgae were immobilized in 4 % sodium alginate discs. Free Chlamydomonas sp. reported the maximum N-NO3- removal percentage (75.08 %) while free Chlorella sp. showed the highest PO43- removal (83.69 %). Most of the cultures removed more than 50 % and 70 % of N-NO3- and PO43-, respectively, during the first day. Immobilization affected negatively the nutrient removal, however, these values were higher or within high ranges of removal reported in previous studies. The results showed that both strains in free or immobilized cultures have the potential to be used for removal of inorganic nutrients in municipal wastewaters, especially for PO43- removal. [ABSTRACT FROM AUTHOR]