Influence of Phosphorus Control on Coupling System ofWinery Wastewater and Microalgae Cultivation

To investigate the optimum phosphorous condition for the coupling system of winery wastewater and microalgae cultivation, changes in growth of Chlamydoomonas reinhardtii and Scenedesmus dimorphus were observed under single culture and co-culture conditions, and the absorption and removal efficiency of nutrients were determined in the wastewater. The effect of different phosphorus concentrations on the dry weight, specific growth rate, protein content, and the removal amount and removal rate of total nitrogen (TN), total phosphorus (TP) and chemical oxygen demand (COD) were studied by the control variable method. The results showed that the demand of Chlamydoomonas reinhardtii for phosphorus was greater than that of Scenedesmus dimorphus. When the initial total phosphorus concentration was 16.40 mg/L and the initial nitrogen to phosphorus ratio was 2.45, as for Chlamydoomonas reinhardtii, the final biomass reached 839.50 mg/L, the algal protein content reached 53.37 mg/L, and the removal rates of TN, TP and COD were 93.48%, 91.75%, 67.90%, respectively; as for Scenedesmus dimorphus, the final biomass reached 650.00 mg/L, the algal protein content reached 131.04 mg/L, and the removal rates of TN, TP and COD were 95.76%, 73.93%, 83.43%, respectively. Under co-culture conditions, the growth curves of the two microalgae were between their growth curves under single culture conditions, the removal rates of TP and TN were 83.66% and 95.24%, respectively, and the removal of COD was similar to that of Scenedesmus dimorphus. It was also found that through the winery wastewater-microalgae cultivation coupling system, whether it is single or co-culture condition, the wastewater can meet the total phosphorus requirements of class Ⅳ water quality specified in the Environmental Quality Standard for Surface Water（GB3838—2002）.