Biorremediación de aguas residuales urbanas provenientes de las descargas hacia el Río Yasnán-Pulamarín del cantón Cayambe-Ecuador mediante el uso de Chlorella SP.

Abstract

This study evaluated the bioremediation capability of Chlorella sp. in wastewater from Cayambe, by inoculating three different concentrations: 0,001; 0,005, and 0,01 g/L in 2 L. Every treatment had three replications and a general control group. Bioreactors were supplied with oxygen and constant photoperiod for 26 days. All the treatments were monitored daily in a Neubauer chamber to follow the growth kinetics. pH was examined weekly, as well as the phosphates, nitrates, and ammonia degradation by spectrophotometry. Finally, BOD and microbiological indicators were analyzed at the beginning and the end of the experiment. The investigation determined that the best concentration was C3 with the removal of 34,68; 84,58 and 95,81 % of nitrates, phosphates, and ammonia respectively. The decrease in BOD was 87.8 %, while the removal of bacteria reached an average of 99 %. As for pH, the initial values of 6,504 ascended to 9 in all treatments, while conductivity remained between a range of 284 and 285 mS/cm. To conclude, the removal capacity of pollutants and pathogens from wastewater is directly related to the concentration of the Chlorella sp. inoculum, being more than an alternative, a necessity to reach the permissible limits: 50 mg/L of BOD5, 10 mg/L of phosphates, 10 mg/L of nitrates, 10mg/L of ammonia and a pH range between 5-9; under the Legislation.