Abstract:

Biofilm, as the main carrier of microbial communities, seriously affects the normal operation of reverse osmosis systems and subsequent water safety. Understanding the potential for biofilm formation and chlorine resistance of chlorine tolerant bacteria is crucial for exploring disinfection strategies and controlling microbial risks in seawater desalination systems. A total of 45 chlorine tolerant bacteria were isolated and identified from water samples of a nuclear power seawater desalination system, of which 62.2% were isolated from the produced water of reverse osmosis system. The crystal violet staining method was used to determine the biofilm formation curves and compare the biofilm formation abilities of 45 chlorine tolerant strains isolated from desalination systems. A total of 22 strong film-forming strains, 14 weak film-forming strains, and 9 non film-forming strains were obtained. Among the strong film-forming strains, 59.1% belonged to the genus Bacillus, and 50.0% were isolated from the produced water of reverse osmosis device of seawater desalination system. The biofilm formation curves of 18 representative bacterial genera, including Bacillus, showed that the dynamic changes in biofilm formation of different strains were basically consistent within 48 hours. The biofilm formation amount of most strains firstly increased to a specific level and then gradually decreased. Strong film-forming strains could form significant biofilms at both gas-liquid and solid-liquid interfaces, and the role of Bacillus in membrane fouling in seawater desalination systems deserved further research.

Key words: chlorine disinfection, chlorine-resistant bacteria, desalination, biofilm

摘要：

生物膜作为微生物群落的主要载体，严重影响反渗透系统的正常运行以及后续用水安全。了解耐氯菌生物膜形成潜力和抗氯性对探索海水淡化系统中消毒策略和控制微生物风险至关重要。在某核电海水淡化系统水样中共分离鉴定出45株耐氯菌，其中62.2%的菌株分离自反渗透系统产水中。采用结晶紫染色法对从海水淡化系统中分离出的45株耐氯菌株进行生物膜形成曲线测定以及生物膜形成能力比较，共得到强成膜菌株22株、弱成膜菌株14株和不成膜菌株9株。强成膜菌株中，59.1%属于芽孢杆菌属（Bacillus），50.0%分离自海水淡化系统反渗透装置产水中。包括Bacillus在内的18株代表菌株的生物膜形成曲线显示，在48 h内不同菌株生物膜成膜动态变化趋势基本一致，大多数菌株的生物膜形成量都呈现先增加至某一特定水平，后逐渐下降的趋势。强成膜菌株在气-液界面和固-液界面都能形成明显生物膜，Bacillus在海水淡化系统膜污染中的作用值得进一步研究。

关键词: 氯消毒, 耐氯菌, 海水淡化, 生物膜

CLC Number: 

• P747