CAREER: Impacts of Marine Algal Blooms on Disinfection Byproduct Formation in Seawater Desalination

标题：职业：海藻大量繁殖对海水淡化消毒副产品形成的影响PI名称：宁戴提案编号：1652412基于反渗透(RO)的海水淡化是满足全球日益增长的水需求的最重要技术之一。在反渗透海水淡化厂的进水口，经常加入消毒剂(例如氯)，以抑制微生物对处理单元的污染，特别是反渗透膜。这些消毒剂可与海洋有机物反应，形成有害的消毒副产物(DBPs)。最近，由于藻类水华期间高浓度的藻类有机物(AOM)，海洋藻类水华通过造成严重的膜污染而中断了海水淡化作业。虽然消毒剂对控制藻类水华期间的污染至关重要，但在海水淡化过程中，高AOM浓度对DBP形成的影响尚未被考虑。在这一项目中，该项目将调查与海藻水华有关的藻类物种形成的DBP，并将为海水淡化作业制定DBP缓解策略。教育活动将侧重于促进所有学位水平的环境工程专业学生的专业能力，并扩大未被充分代表的群体在科学、技术、工程和数学(STEM)领域的参与。该项目将侧重于从海藻中形成DBP的基本原理，以及将研究结果应用于海水淡化作业。该项目将包括四个研究目标。首先，将在模拟藻华期间海水淡化消毒的条件下，评估与水华相关的海洋藻类物种形成DBP的潜力。具有代表性的物种将根据它们与美国海岸海藻大量繁殖的相关性来选择。藻类培养和提取的细胞内外AOM将受到一套消毒剂、氯、氯胺、二氧化氯、臭氧、高锰酸盐及其组合的影响。其次，对来自不同藻类生长阶段的新鲜AOM和生物和非生物转化后的陈化AOM进行DBP形成评价。第三，将确定从海藻细胞中形成DBP的机制以及重要的DBP前体。海水淡化情景下DBP形成的基本知识将是设计海水淡化设施DBP预防策略的基础。最后，将表征消毒过程中AOM转化对其膜污染电位的影响，以提出在膜污染控制和DBP预防之间取得平衡的策略。将使用气、液和尺寸排除层析、质谱分析和分光光度等分析工具来监测DBP的形成和表征AOM的转化。综合教育活动将包括研究生研究和指导方面的培训，为本科生提供研究经验，在研究生和本科环境工程课程中融入基于合作设计的项目学习，以及以高中和中学教师发展为重点的K-12外展。

Title: CAREER: Impacts of Marine Algal Blooms on Disinfection By-Product Formation in Seawater DesalinationPI Name: Ning Dai Proposal Number: 1652412 Reverse osmosis (RO)-based seawater desalination is one of the most important technologies for meeting the growing global water demand. At the intake of RO desalination plants, disinfectants (e.g., chlorine) are often added to suppress fouling of the treatment units, especially RO membranes, by microorganisms. These disinfectants can react with marine organic matter to form harmful disinfection by-products (DBPs). Recently, marine algal blooms were shown to interrupt desalination operations by causing severe membrane fouling, as a result of the high concentration of algal organic matter (AOM) during algal blooms. While disinfectants are crucial for controlling fouling during algal blooms, the implications of high AOM concentrations on DBP formation in desalination have not been considered. In this project the PI will investigate the formation of DBPs from algae species relevant to marine algal blooms and will develop DBP mitigation strategies for desalination operations. Education activities will focus on promoting professional competencies of environmental engineering students at all degree levels and on broadening participation of underrepresented groups in science, technology, engineering, and mathematics (STEM). This project will focus on both the fundamentals of DBP formation from marine algae and the application of findings to desalination operations. The project will encompass four research objectives. First, the DBP formation potential of bloom-relevant marine algae species will be evaluated under conditions simulating disinfection in seawater desalination during algal blooms. Representative species will be selected based on their relevance to marine algal blooms along the US coasts. The algae culture and the extracted intra- and extra-cellular AOM will be subjected to a suite of disinfectants, chlorine, chloramine, chlorine dioxide, ozone, permanganate, and their combinations. Second, DBP formation will be evaluated for fresh AOM derived from different algae growth stages and aged AOM after biotic and abiotic transformation. Third, the mechanisms of DBP formation from marine algae cells and the important DBP precursors will be identified. The fundamental knowledge of DBP formation under desalination scenario will be the basis for designing DBP prevention strategies for desalination facilities. Lastly, the effects of AOM transformation upon disinfection on its membrane fouling potential will be characterized to suggest strategies to achieve a balance between membrane fouling control and DBP prevention. Analytical tools such as gas, liquid, and size exclusion chromatography, mass spectrometry, and spectrophotometry will be employed to monitor DBP formation and characterize AOM transformation. The integral educational activities will include graduate student training in research and mentoring, providing research experience for undergraduates, incorporating cooperative design project-based learning in graduate and undergraduate environmental engineering courses, and K-12 outreach focusing on high school and middle school teacher development.