ABSTRACT

Photosynthetic bacteria (PSB) can be used in wastewater treatment to simultaneously remove pollutants and produce valuable biomass. In this study, PSB were used to treat lactic acid wastewater and produce high-value substances (protein, carotenoid and bacteriochlorophyll). The results showed that the PSB biomass increase, COD and ${\mathrm{NH}}_4^{+}\text{-}\mathrm{N}$ removal reached 55%, 89% and 94% in 5 days, respectively. The protein content, carotenoid and bacteriochlorophyll concentrations reached 69.1%, 2.3 and 0.8 mg/L, respectively. Furthermore, kinetic analysis showed that both ${\mathrm{NH}}_4^{+}\text{-}\mathrm{N}$ removal and protein content fitted the Boltzmann equation, and the ${\mathrm{NH}}_4^{+}\text{-}\mathrm{N}$ removal was positively related with the content of protein and concentration of pigments. This novel wastewater treatment method can adapt to the changes of light-oxygen condition, F/M and pH conditions.

Highlights

(1) PSB effectively treated real lactic acid wastewater with zero excess sludge.

(2) 69% of protein and 2.3 mg/L of carotenoid were produced in the process.

(3) ${\mathrm{NH}}_4^{+}\text{-}\mathrm{N}$ removal was positively related with the content of protein and pigments.

摘要

光合细菌 (PSB) 可用于废水处理，以同时去除污染物并产生有价值的生物质。在这项研究中，PSB被用于处理乳酸废水并生产高价值物质（蛋白质、类胡萝卜素和细菌叶绿素）。结果表明，PSB生物量增加，COD和${\mathrm{NH}}_4^{+}\text{-}\mathrm{ñ}$5 天内去除率分别达到 55%、89% 和 94%。蛋白质含量、类胡萝卜素和细菌叶绿素浓度分别达到69.1%、2.3和0.8 mg/L。此外，动力学分析表明，两者${\mathrm{NH}}_4^{+}\text{-}\mathrm{ñ}$去除和蛋白质含量符合玻尔兹曼方程，并且${\mathrm{NH}}_4^{+}\text{-}\mathrm{ñ}$去除与蛋白质含量和色素浓度呈正相关。这种新型废水处理方法可以适应光氧条件、F/M和pH条件的变化。

强调

(1) PSB有效处理纯乳酸废水，剩余污泥为零。

(2)该过程产生了69%的蛋白质和2.3 mg/L的类胡萝卜素。

(3)${\mathrm{NH}}_4^{+}\text{-}\mathrm{ñ}$去除与蛋白质和色素的含量呈正相关。