Wang Jian-Hui, Chen You-Peng, Dong Yang, Wang Xi-Xi, Guo Jin-Song, Shen Yu, Yan Peng, Ma Teng-Fei, Sun Xiu-Qian, Fang Fang, Wang Jing
Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China.
Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China; Key Laboratory of Reservoir Aquatic Environment of CAS, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China.
Environ Pollut. 2017 Oct;229:199-209. doi: 10.1016/j.envpol.2017.05.062. Epub 2017 Jun 6.
Biofilms in natural environments offer a superior solution to mitigate water pollution. Artificially intensified biofilm reactors represented by rotating biological contactors (RBCs) are widely applied and studied. Understanding the oxygen transfer process in biofilms is an important aspect of these studies, and describing this process in moving biofilms (such as biofilms in RBCs) is a particular challenge. Oxygen transfer in RBCs behaves differently than in other biological reactors due to the special oxygen supply mode that results from alternate exposure of the biofilm to wastewater and air. The study of oxygen transfer in biofilms is indispensable for understanding biodegradation in RBCs. However, the mechanisms are still not well known due to a lack of effective tools to dynamically analyze oxygen diffusion, reaction, and microdistribution in biofilms. A new experimental device, the Oxygen Transfer Modeling Device (OTMD), was designed and manufactured for this purpose, and a mathematical model was developed to model oxygen transfer in biofilm produced by an RBC. This device allowed the simulation of the local environment around the biofilm during normal RBC operation, and oxygen concentrations varying with time and depth in biofilm were measured using an oxygen microelectrode. The experimental data conformed well to the model description, indicating that the OTMD and the model were stable and reliable. Moreover, the OTMD offered a flexible approach to study the impact of a single-factor on oxygen transfer in moving biofilms. In situ environment of biofilm in an RBC was simulated, and dynamic oxygen microdistributions in the biofilm were measured and well fitted to the built model description.
自然环境中的生物膜为减轻水污染提供了一种更优的解决方案。以旋转生物接触器（RBC）为代表的人工强化生物膜反应器得到了广泛应用和研究。了解生物膜中的氧传递过程是这些研究的一个重要方面，而描述移动生物膜（如RBC中的生物膜）中的这一过程是一项特殊挑战。由于生物膜交替暴露于废水和空气中导致的特殊供氧模式，RBC中的氧传递行为与其他生物反应器不同。研究生物膜中的氧传递对于理解RBC中的生物降解是必不可少的。然而，由于缺乏有效工具来动态分析生物膜中的氧扩散、反应和微分布，其机制仍不太清楚。为此设计并制造了一种新的实验装置——氧传递建模装置（OTMD），并开发了一个数学模型来模拟RBC产生的生物膜中的氧传递。该装置能够模拟正常RBC运行期间生物膜周围的局部环境，并使用氧微电极测量生物膜中氧浓度随时间和深度的变化。实验数据与模型描述吻合良好，表明OTMD和模型稳定可靠。此外，OTMD为研究单一因素对移动生物膜中氧传递的影响提供了一种灵活的方法。模拟了RBC中生物膜的原位环境，并测量了生物膜中的动态氧微分布，且与建立的模型描述拟合良好。
