Abstract: Against the backdrop of the “dual-carbon” goals, the algae-photovoltaic complementarity model combines clean energy production with biological carbon sequestration, offering a new pathway for low-carbon development in major cities. This pilot-scale study at Shanghai PDG Zero Carbon Green Valley Park, kitchen waste AnMBR effluent was used as the nutrient solution, with the addition of K2HPO4 to adjust the N/P ratio, a semi-continuous cultivation experiment of Chlorella sp. in a landfill was carried out for 211 days by combining a closed-type photobioreactor with photovoltaics. During the experiment, the growth status, nutrient consumption, and water quality changes were monitored. The results indicated that Chlorella sp. biomass was highest in summer, followed by spring, and lower in autumn and winter, which was closely related to solar altitude, shading rate, and ambient temperature. The microalgae showed effective utilization of nitrogen and phosphorus nutrients as well as organic pollutants, with average effluent values for TN, TP, NH3-N, and COD of (136.1±83.3) mg/L, (12.6±6.6) mg/L, (133.8±90.2) mg/L, and (123.6±81.6) mg/L, respectively. The optimal cultivation conditions obtained in the pilot-scale experiment were a temperature of (25.50±3.88) ℃, a light intensity of (21 783±11 256) lux, an N/P ratio of 12.0, a CO2 feeding rate of 0.37 L/min, and a pH of 6.59±0.23.

Key words: landfill, microalgae, photovoltaic, AnMBR effluent, resource recovery