Developing a More Fundamental Understanding of Drinking Water Biofiltration

对饮用水生物过滤有更基本的了解

• 批准号: RGPIN-2015-06369
• 负责人: Huck, Peter
• 金额: $ 2.48万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=685218
• 关键词: Developing; More; Fundamental; Understanding; Drinking

***In the last decade, the interest in using biological processes as part of drinking water treatment has increased substantially. This is driven by their ability to biodegrade portions of the natural organic matter (NOM) in water that can interfere with good treatment. A classical issue associated with NOM is the formation of potentially harmful disinfection byproducts.***Of particular interest is rapid biofiltration, which takes place in filters normally used for particle and pathogen removal. In the absence of a disinfectant residual, the very high surface area in the filters allows for the development of biofilm that can undertake biodegradation. In the last several years, research has shown that such biofilters can also effectively reduce the concentrations of biopolymers, the high molecular weight fraction of the NOM. Biopolymers have been shown to be critical in fouling low-pressure membranes such as ultrafiltration that are increasingly being used for pathogen and particle removal in drinking water treatment. This defines a potential new application for biofiltration, i.e. as a "green" membrane pretreatment. In the last several years, a significant portion of the applicant's research has been directed towards this.***In the conduct of this research several important issues have arisen that require more fundamentally-oriented investigation. These research questions form the basis of this application and are important for the understanding and successful application of biofiltration, regardless of its treatment objective.***The first issue is that conflicting information has appeared in the literature regarding the appropriate macronutrient ratio for biofilters so that nitrogen or phosphorus are not limiting. This is of important practical significance, because if, for example, phosphorus were to be supplemented, it could potentially need to be removed at the downstream wastewater treatment plants. Additionally, the role of extracellular polymeric substances (EPS) in biofiltration has not been properly addressed. Further, commonly used parameters to quantify biomass such as adenosine triphosphate (ATP) have been shown not to have a unique relationship with biofilter performance.***A second research question is that in terms of biofiltration as a membrane pretreatment, the biodegradability of the biopolymer fraction appears to be different for different waters. Ozonation prior to biofiltration assists in reducing membrane fouling, but appears to negatively impact the removal of biopolymers by biofiltration.*** ***Because biofiltration can also remove the easily biodegradable NOM that contributes to biofouling in reverse osmosis (RO) membranes used for desalination, a third need is to explore biofiltration's potential in RO applications, where it could reduce chemical usage for membrane cleaning.*** **

* 在过去十年中，对使用生物工艺作为饮用水处理的一部分的兴趣大幅增加。这是由它们生物降解水中部分天然有机物（NOM）的能力驱动的，这些有机物可能会干扰良好的处理。与NOM相关的一个经典问题是形成潜在有害的消毒副产物。*特别令人感兴趣的是快速生物过滤，其发生在通常用于颗粒和病原体去除的过滤器中。在没有消毒剂残留的情况下，过滤器中非常高的表面积允许生物膜的发展，可以进行生物降解。在过去的几年中，研究表明，这种生物过滤器还可以有效地降低生物聚合物的浓度，NOM.Biopolymers的高分子量馏分已被证明是污染的低压膜，如超滤，越来越多地被用于病原体和颗粒去除饮用水处理中的关键。这定义了生物过滤的潜在新应用，即作为“绿色”膜预处理。在过去的几年里，申请人的研究有很大一部分是针对这一点的。在进行这项研究的几个重要问题已经出现，需要更多的基本面向调查。这些研究问题构成了这种应用的基础，对于理解和成功应用生物过滤非常重要，无论其处理目的如何。第一个问题是，在文献中出现了关于生物过滤器的适当常量营养素比例的相互矛盾的信息，因此氮或磷不是限制性的。这具有重要的实际意义，因为例如，如果要补充磷，则可能需要在下游废水处理厂去除磷。此外，胞外聚合物（EPS）在生物过滤中的作用还没有得到适当的解决。此外，用于量化生物量的常用参数，如三磷酸腺苷（ATP），已被证明与生物过滤器性能没有独特的关系。第二个研究问题是，在作为膜预处理的生物过滤方面，生物聚合物级分的生物降解性对于不同的沃茨似乎是不同的。生物过滤前的臭氧化有助于减少膜污染，但似乎对生物过滤去除生物聚合物产生负面影响。 * 由于生物过滤还可以去除容易生物降解的NOM，这种NOM有助于用于脱盐的反渗透（RO）膜中的生物污染，因此第三个需求是探索生物过滤在RO应用中的潜力，它可以减少膜清洁的化学品使用。 **