Study on the growth of a native microalgae-bacteria mixed culture from the Peruvian Andes exposed to different tannery effluent dilutions and photoperiod

Monzón Martínez L.; Atayupanqui Dueñas R.; González Sánchez A.; Montalvo Andia J. · Environmental Technology (United Kingdom) (2025) · DOI: 10.1080/09593330.2025.2485354

Resumen

This study evaluated the suitability of wastewater treatment from tanneries located in the city of Arequipa, Peru. The growth of the microalgae-bacteria consortium enriched from wastewater ponds located in high altitude (2300 m above sea level) and areas with high ultraviolet radiation, was characterized under different wastewater dilutions, nutrient-corrected wastewater and various light periods in a laboratory-scale air-lift system over a 9-day cultivation period. The results indicate a higher COD removal at low dilutions (50%) in both 16L:8D and 24L:0D photoperiods, achieving 43.63% and 42.93%, respectively, however, a higher daily consumption rate was observed in treatments with 75% and 100% tannery wastewater, with the highest COD consumption recorded in the 100% treatment under the 16L:8D photoperiod, with at 85.50 mg L⁻¹ d⁻¹. Regarding nitrogen removal and consumption, significant results were obtained in the 100% treatment with 16L:8D photoperiod with values of 55.46% and 3.81 mg L−1 d−1 respectively, while for phosphorus all treatments had high removals (>95%). On the other hand, the highest productivity occurred in the 100% treatment for both the 16L:8D and 24;0 photoperiod with a value of 52.85 and 64.28 mg L−1 d −1 respectively. Finally, by phosphorous supplementation in the medium, the productivity in all treatments improved, obtaining the maximum biomass productivity in the 75% 24L:0D treatment with 95,714 mg L−1 d−1. The maximum accumulation of lipids was 18.7% of the effluent with 100%, 16L:8D photoperiod. These results confirm that microalgae technology is an ecofriendly alternative to treat tannery beam house wastewaters.

Instituciones: Universidad Católica San Pablo