小球藻生长及协同净化畜禽养殖废水研究

Study of Chlorella vulgaris growth coupled with purification of livestock and poultry aquaculture wastewater

为了研究小球藻在模拟畜禽养殖废水中的生长特性及其对高质量浓度有机物废水的协同净化效果,分析小球藻在自养/异养混合代谢生长模式下对有机与无机碳源的竞争利用策略以及外加无机碳源对小球藻生长与废水净化能力的影响规律。研究结果表明:在高质量浓度有机碳(化学需氧量质量浓度ρCOD为(1172±22.5)mg/L)存在条件下,一定浓度的无机碳(0.1~1μmoL/L)可以促进小球藻的生长及其对有机物的吸收,COD去除率可提高12.9%~40.4%,同时小球藻合成积累油脂和叶绿素能力也得到提高,藻细胞内总叶绿素质量浓度高达(8.6±0.06)mg/L,单个藻细胞中油脂质量达(0.26±0.004)ng。但当无机碳源的浓度继续提高到2.1mmoL/L时,小球藻的生长和废水有机碳利用速率明显受到抑制,小球藻的比生长速率下降(6.5±2.1)%,COD去除率只有(68.8±5.6)%,但对氮磷去除率影响不大,总氮、总磷、氨氮的去除率分别为(97.0±0.6)%,(86.8±3.8)%和100%。

To study the growth of Chlorella vulgaris and its role in purification of synthetic livestock wastewater whose high mass concentration of organic matter, the competition strategy of organic and inorganic carbon sources and the influence of inorganic carbon sources on the growth of C. vulgaris and wastewater treatment were analyzed. The results show that in condition of high mass concentration of organic matter (chemical oxygen demand mass concentration ρCOD is (1 172±22.5) mg/L), the growth of C. vulgaris and the removal efficiencies of nitrogen and phosphorus are promoted by the addition of 0.1-1.0 μmoL/L inorganic carbon. The COD removal efficiency increases by 12.9%~40.4%. Meanwhile, the mass concentration of lipid in C. vulgaris cell increases to (8.6±0.06) mg/L and the mass of oil in a single algal cell is (0.26±0.004) ng. However, when the inorganic source carbon concentration further increases to 2.1 mmol/L, the cell growth rate and the utilization efficiency of organic carbon are limited. The growth rate of C. vulgaris decreases by (6.5± 2.1)%, and the COD removal efficiency is merely (68.8±5.6)%. In contrast, total nitrogen, total phosphorus and ammonia nitrogen removal efficiencies are significantly affected, which are (97.0±0.6)%,(86.8±3.8)% and 100%, respectively.