Efficiency of the microalgae Spirulina platensis in the bioremediation of leachate from the San Jeronimo De Tunan solid waste treatment plant, Junin, Peru

Abstract

The purpose of this work was to evaluate the efficacy of the microalgae Spirulina platensis in the bioremediation of leachate from the solid waste treatment plant of San Jerónimo de Tunán, Junín, Peru. Initially, a pilot test was carried out using undiluted leachate (100%) in which no microalgal growth was evidenced, in response to this, a second experimental phase was designed using a 40% dilution with distilled water complemented with essential mineral salts to optimize the culture medium. Treatments were established with different volumes of microalgae: N-01 and N-02 with 550 mL, and M-01 and M-02 with 750 mL. The experimental tests were carried out overseven days for N-01 and M-01, and fourteen days for N-02 and M-02. During the experimental period, physicochemical parameters (pH, temperature, electrical conductivity, turbidity, BOD and COD) were monitored, as wellas the removal capacity of heavy metals (lead, zinc, iron, chromium, arsenic and cadmium). The results showed adecrease in turbidity, with final values of 42.56 and 35.9 NTU in the one-week treatments (N-01 and M-01) andin the two-week treatments (N-02 and M-02) values of 45.3 and 49.43 NTU were recorded respectively. BODand COD values, especially in longer duration treatments, BOD was reduced between 15.98% and 19.86% in oneweek, reaching up to 34.31% and 37.09% in two weeks. On the other hand, COD was reduced by 24.57% and26.62% in one week, and up to 42.08% and 45.23% in two weeks. Regarding heavy metals, variable removalswere obtained: lead (69.33–80.67%), zinc (44.34–50.91%), iron (70.73–75.72%), chromium (64.73–75.84%), arsenic (61.49–64.87%) and cadmium (55.55–73.33%). The findings support the potential of Spirulina platensis asan effective and promising alternative for leachate bioremediation.